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**Report To Congress**

**The Satellite Home Viewer Extension**

**And Reauthorization Act Of 2004**

**Study Of**

**Digital Television Field Strength Standards**

**And**

**Testing Procedures**

**ET Docket No. 05-182**

**Adopted: December 6, 2005 Released: December 9, 2005**

> **Table of Contents**

[Paragraph]{.underline}

I. SUMMARY 1

II\. BACKGROUND 3

III\. THE DIGITAL TV SIGNAL STRENGTH STANDARDS 10

IV\. DIGITAL TELEVISION FIELD STRENGTH MEASUREMENT PROCEDURES 109

V. PREDICTIVE MODELING 132

[Page]{.underline}

APPENDIX A

Section 339(c)(1) of the Communications Act of 1934, As Amended A-1

APPENDIX B

Parties Submitting Comments and Reply Comments B-1

APPENDIX C

Tests of ATSC 8-VSB Reception Performance of Consumer Digital Television
Receivers\
Available in 2005 C-1

APPENDIX D

Notice of Inquiry D-1

APPENDIX E

Comments and Reply Comments to Notice of Inquiry E-1

**ACKNOWLEDGEMENTS**

This Report was prepared under the leadership of the Office of
Engineering and Technology, in cooperation with the Media Bureau.

## Office of Engineering and Technology {#office-of-engineering-and-technology .unnumbered}

> Ron Chase, Bruce Franca, Charles Iseman, Ira Keltz, Stephen Martin,
> Alan Stillwell, David Sturdivant

## Media Bureau {#media-bureau .unnumbered}

Eloise Gore

## I. SUMMARY {#i.-summary .unnumbered}

1.  Section 204(b) of the Satellite Home Viewer Extension and
    Reauthorization Act of 2004 (SHVERA) requires that the Federal
    Communication Commission (Commission) conduct an inquiry and develop
    recommendations regarding whether the Commission's digital signal
    strength standard and the signal testing procedures used to identify
    if a household is "unserved" for purposes of the satellite statutory
    copyright license for distant digital signals should be revised.[^1]
    This Report is in fulfillment of Congress' directives to the
    Commission in Section 204(b) of the SHVERA.

2.  Consistent with the SHVERA Section 204(b) directives, the Report
    describes the results of the Commission's study and *Inquiry* on
    this matter and the Commission's findings regarding whether changes
    should be made to the statutes or the Commission's rules. As set
    forth in detail below, the Commission specifically finds that:

-   No specific changes are needed to the digital television field
    strength standards and/or planning factors for purposes of
    determining whether a household is eligible to receive retransmitted
    distant network television signals.

-   The Commission should conduct a rule making proceeding to specify
    procedures for measuring the field strength of digital television
    signals at individual locations that are generally similar to the
    current procedures for measuring the field strength of analog
    television stations. Certain modifications to those procedures are
    needed, however, to address differences in analog and digital
    television signals. The proper procedures for measuring digital
    television signals would be developed through the recommended rule
    making proceeding.

-   The existing improved Individual Location Longley-Rice (ILLR) model
    should be used for predicting whether a household is unserved by
    digital television signals. The Commission specifically recommends
    that Congress amend the copyright law, as well as the Communications
    Act, to allow a predictive model to be used in connection with
    eligibility for a distant digital signal. The Commission further
    recommends that Congress provide the Commission with authority to
    adopt the existing improved ILLR model as a predictive method for
    determining households that are unserved by local digital signals
    for purposes of establishing eligibility to receive retransmitted
    distant network signals under the SHVERA.

The Report also includes a study of digital television receiver
performance, attached hereto as Appendix C, that, *inter alia*, finds
that there is no relationship between the ability of currently available
digital television receivers' to receive over-the-air signals and the
prices of those receivers.

## II. BACKGROUND {#ii.-background .unnumbered}

3.  Broadcast television stations have rights, under the Copyright
    Act[^2] and private contracts, to control the distribution of the
    national and local programming that they transmit. In 1988, Congress
    adopted the Satellite Home Viewer Act (SHVA) as an amendment to the
    Copyright Act in order to protect the broadcasters\' interests in
    their programming while simultaneously enabling satellite carriers
    to provide broadcast programming to those satellite subscribers who
    are unable to obtain broadcast network programming over the air.
    Under the SHVA, these subscribers were generally considered to be
    \"unserved\" by their local stations. In the SHVA, Congress linked
    the definition of \"unserved households\" to a Commission-defined
    measure of analog television signal strength known as \"Grade B
    intensity.\"[^3] The Grade B signal intensity standard, as set forth
    in Section 73.683(a) of the Commission's rules, is used to identify
    a geographic contour that defines an analog television station's
    service area.[^4] For digital television stations, the counterpart
    to the Grade B signal intensity standards for analog television
    stations are the values set forth in Section 73.622(e) of the
    Commission\'s Rules describing the DTV noise-limited service
    contour.[^5]

4.  The new Section 339 requires the Commission to conduct an inquiry
    regarding whether, for purposes of identifying if a household is
    unserved by a digital signal under Section 119(d)(10) of Title 17,
    United States Code, the digital signal strength standards in Section
    73.622(e)(1) of the Commission's rules, or the testing procedures in
    Section 73.686(d) of the Commission's rules, should be revised to
    take into account the types of antennas that are available to
    consumers.[^6] In 1999, the Commission adopted a *Report and Order*
    (*SHVA Report and* Order) addressing three major issues that arose
    in the context of the SHVA and several pending court actions and
    petitions to the Commission.[^7] First, it affirmed the existing
    definition of a signal of Grade B intensity for use in determining
    eligibility for reception of distant network signals. Second, the
    Commission adopted rules for determining whether a household is able
    to receive an analog television signal of this strength.[^8] In
    particular, the Commission adopted rules establishing a standardized
    method for measuring the strength of analog television signals
    on-site at individual locations. And finally, it endorsed a method
    for predicting the strength of such signals that could be used in
    place of actually taking measurements.[^9]

5.  As added under the Satellite Home Viewer Improvement Act of 1999
    (SHVIA),[^10] the then-new Section 339(c)(3) of the Communications
    Act required that the Commission develop and prescribe by rule a
    point-to-point predictive model for reliably and presumptively
    determining the ability of individual locations to receive signals
    in accordance with the signal intensity standard in effect under
    Section 119(d)(10)(A) of Title 17 of the Unites States Code, that
    is, the Grade B standards.[^11] Section 339(c)(3) further required
    that the Commission rely on the ILLR model which the Commission had
    earlier developed for such predictions and that the Commission
    ensure that such model takes into account terrain, building
    structure, and other land cover variations. In response to these
    provisions, the Commission adopted a *First Report and Order* in May
    2000 in which it amended its rules to prescribe use of an improved
    point-to-point ILLR model for establishing whether individual
    households are eligible to receive distant analog network television
    signals.[^12] This model includes adjustments for land use and land
    cover loss values. The rules also provide for a neutral and
    independent entity to evaluate the qualifications of potential
    testers to conduct on-site signal strength measurements in cases
    where a network television station denies a subscriber's request for
    a waiver of the ILLR prediction that the viewer is "served."

6.  In addition, in the SHVIA Congress directed the Commission to
    conduct an inquiry and prepare a report regarding the broadcast TV
    signal strength standard used for satellite carrier purposes. The
    then-new Section 339(c)(1) of the Communications Act required that
    this investigation evaluate all possible standards and factors for
    determining eligibility to receive retransmitted network station
    signals and, if appropriate, recommend modification of, or
    alternative standards or factors, to the Grade B intensity standard
    for analog television signals and to make a further recommendation
    relating to an appropriate standard for digital television
    signals.[^13] In response to this directive, the Commission inquired
    into and evaluated the possible standards and factors for
    determining eligibility of households to receive retransmissions of
    network station signals by satellite carriers. It specifically
    considered whether to recommend modifications to, or alternative
    standards or factors for, the Grade B intensity standard for analog
    television signals. On November 29, 2000, the Commission issued a
    *Report to Congress* (*SHVIA Report*) in which it recommended
    retention of the Grade B signal intensity standard and eight of the
    nine planning factors used in developing that standard as the basis
    for predicting whether a household is eligible to receive
    retransmitted distant TV network analog signals under the
    SHVIA.[^14] The Commission recommended modification of the remaining
    planning factor (time fading) by replacing the existing fixed values
    with location-dependent values determined for the actual receiving
    locations using the Individual Location Longley-Rice (ILLR)
    prediction model. With regard to digital signals, the Commission
    found that it would be premature to construct a distant network
    signal eligibility standard for DTV signals at that time. The
    Commission therefore recommended that establishment of a distant
    network signal eligibility standard for digital signals be deferred
    until such time as more substantial DTV penetration is achieved and
    more experience is gained with DTV operation.[^15]

7.  In December 2004, Congress enacted the SHVERA, which revised the
    statutory provisions of the SHVA and SHVIA, including Section 339 of
    the Communications Act of 1934.[^16] Under the SHVERA, viewers in
    individual households who are not able to receive network digital
    television signals over-the-air from local television stations and
    who are in circumstances that meet certain additional qualifying
    criteria are eligible to receive those digital network television
    signals from distant stations carried via satellite. It is therefore
    important that the standard for determining whether a local digital
    television station's signal strength at a specific location is
    sufficient for reception of service and that the procedures for
    evaluating digital television signal strength provide an accurate
    means for determining whether a household can receive a local
    network station's digital signal. Subsection 339(a)(2)(D)(vi), as
    revised by SHVERA, provides that the digital signal strength
    standard defined in Section 73.622(e) of the Commission's rules
    shall serve as the basis for determining whether a satellite TV
    subscriber is eligible to receive retransmitted distant TV network
    digital signals.[^17] Section 73.622(e)(1) provides that the service
    area of a DTV station is the geographic area within the station's
    noise-limited F(50, 90) contour where its signal is predicted to
    exceed the noise-limited service level.[^18] Within this contour,
    service is considered available at locations where the station's
    signal strength, as predicted using the terrain dependent
    Longley-Rice point-to-point propagation model, exceeds the following
    noise-limited service levels:[^19]

Channels 2-6 (low-VHF) 28 dBu

Channels 7-13 (high-VHF) 36 dBu

Channels 14-69 (UHF) 41 dBu

8.  Subsection 339(c)(1), as revised by the SHVERA, requires the
    Commission, not later than December 8, 2005, to complete an inquiry
    and submit a report recommending whether, for purposes of
    identifying if a household is unserved by an adequate digital
    signal, the digital signal strength standard set forth in Section
    73.622(e)(1) of the Commission's Rules or the testing procedures in
    Section 73.686(d) of the Commission's Rules should be revised to
    take into account the types of antennas that are available to
    consumers.[^20] Subsection 339(c)(1) requires that, in conducting
    the required study, the Commission consider six specific issues
    relating to the question of digital signal strength in the context
    of the "unserved household":[^21]

-   Whether to account for the fact that an antenna can be mounted on a
    roof or placed in a home and can be fixed or capable of rotating;

-   Whether the Commission's rules should be amended to create different
    procedures for determining if the requisite digital signal strength
    is present than for determining if the requisite analog signal
    strength is present;

-   Whether a standard should be used other than the presence of a
    signal of a certain strength to ensure that a household can receive
    a high-quality picture using antennas of reasonable cost and ease of
    installation;

-   Whether to develop a predictive methodology for determining whether
    a household is unserved by an adequate digital signal;

-   Whether there is a wide variation in the ability of reasonably
    priced consumer digital television sets to receive over-the-air
    signals, such that at a given signal strength some may be able to
    display high-quality pictures while others cannot, whether such
    variation is related to the price of the television set, and whether
    such variation should be factored into setting a standard for
    determining whether a household is unserved by an adequate digital
    signal; and

-   Whether to account for factors such as building loss, external
    interference sources, or undesired signals from both digital
    television and analog television stations using either the same or
    adjacent channels in nearby markets, foliage, and man-made clutter.

    The above specifications for study address three separate but
    interrelated concerns: 1) the appropriateness of the DTV planning
    factors that underlie the DTV signal strength standard, 2) the
    appropriateness of the objective test-site methodology for measuring
    digital signals, and 3) whether a predictive model should be
    developed for determining whether a household is unserved by an
    adequate digital TV signal for purposes of eligibility to receive
    distant network TV signals.

9.  On April 29, 2005, the Commission initiated an inquiry to gather
    information pursuant to Section 339(c)(1).[^22] The Commission
    received 9 comments and 5 reply comments in response to its *Notice
    of Inquiry* (*Inquiry*) in this proceeding. The results of the
    Commission's study and analysis of the record of its *Inquiry* and
    other research and information in this matter and its
    recommendations are described in the following sections of this
    Report. These sections address the digital signal strength
    standards, testing procedures, and predictive models and
    specifically include consideration of the six issues that Congress
    specifically asked the Commission to address in Section 204 of the
    SHVERA.

## III. THE DIGITAL TV SIGNAL STRENGTH STANDARDS {#iii.-the-digital-tv-signal-strength-standards .unnumbered}

10. Eligibility to receive distant network signals retransmitted by a
    satellite carrier has been, in principle, based on the inability of
    a household subscribing to a Direct Broadcast Satellite (DBS)
    service is not able to receive network signals over-the-air at its
    location using a receiving system that conforms to the assumed
    receiving system on which the television service area standards are
    based.[^23] If a household is not able to receive a network signal
    at a field strength level equal to or greater than the TV service
    area Grade B (analog TV) or noise-limited (digital TV) standards,
    that household may be eligible to receive the signal of a distant
    station affiliated with that network that is retransmitted on the
    household's DBS service if it meets other criteria for eligibility.
    Congress has asked the Commission to investigate whether the
    noise-limited DTV service standard should be revised to take into
    account the types of antennas that are available to consumers. In
    considering this issue, the Commission must consider: 1) whether to
    account for the fact that an antenna can be mounted on a roof or
    placed in a home and can be fixed or capable of rotating, 2) whether
    there is a wide variation in the ability of reasonable priced
    consumer digital television sets to receive over-the-air signals
    such that at a given signal strength some may be able to display
    high-quality pictures while others may not, whether such variation
    is related to the price of the television set, and whether such
    variation should be factored into setting a standard for determining
    whether a household is unserved by an adequate digital signal,
    and 3) whether to account for factors such as building loss,
    external interference sources, or undesired signals from both
    digital television and analog television stations using either the
    same or adjacent channels in nearby markets, foliage, and man-made
    clutter. In this section, we discuss the digital TV signal strength
    standards and evaluate the factors underlying those standards,
    including those specified in Section 204, in light of our *Inquiry*
    and study. We also consider whether any adjustments to those
    standards are warranted in light of our findings.

A. The DTV Service Area Field Strength Intensity Standards

11. As indicated above, the service areas of broadcast television
    stations, in the absence of interference, are defined on the basis
    of a concept known as "noise-limited" service. Under this concept, a
    TV station's service extends to cover geographic locations out to
    the edge of where reception is no longer possible because of
    interference from background electrical noise. The background noise
    limiting reception of service arises both from the environment and
    from within the equipment used to receive service. Both the analog
    TV Grade B field strength intensity standards and the digital TV
    noise-limited field strength intensity standards are defined on this
    basis. These standards were developed in the early days of both
    methods of television modulation as a key component of the
    Commission's television station channel allotment and service area
    regulations.[^24] The DTV service area definitions further specify
    that service is considered to be present in areas within the
    noise-limited contour where signal strength is predicted to exceed
    the noise-limited signal level using the terrain-dependent
    Longley-Rice point-to-point propagation model.[^25]

12. The field strength of television signals decreases with distance
    from the transmitter and varies across individual locations and
    time. At locations close to a station's transmitter the variation of
    signal strength across time and location are generally not great.
    However, as distance increases, the variability of the available
    signal strength with both location and time increases significantly.
    At the edge of a station's service area, its signal will be
    available in some locations more of the time than at others.
    Historically, if service is not available all, or most of the time,
    it is simply considered not available. Under both the analog Grade B
    and digital noise-limited F(50,90) service standards, an acceptable
    television picture and sound service is available at 50% of the
    locations for 90% of the time at locations on the outer edge of a
    station's service area. The signal strength values of the analog TV
    standards were selected to provide service at these levels of
    availability and the digital television standards were specified to
    enable DTV stations to replicate their analog service.[^26]

13. The noise-limited digital TV field strength standards were derived
    from a set of assumptions for the several technical planning factors
    that are present in a typical DTV receiving system and for a defined
    level of service. The DTV receiving system includes all elements in
    the electrical path from the point where a DTV signal is converted
    from electromagnetic energy to electric energy at the receive
    antenna to the point in the tuning function of a TV set where the
    received signal is delivered to the demodulator that produces the
    19.39 mbps digital TV bitstream. The effect of each of the elements
    in the receiving system and the factors for time and location
    variability are summed to determine the minimum signal level that
    must be available over-the-air to provide an F(50,90) level of
    service at the edge of a station's noise-limited service area
    contour. These factors and their assumed values as used in
    establishing the DTV noise-limited service area field strength
    intensity standards are:[^27]

+------------------------+----------+----------+-----------+---------+
| Planning Factor:       | Symbol   | Low VHF  | High VHF  | UHF     |
|                        |          |          |           |         |
|                        |          | (2-6)    | (7-13)    | (14-69) |
+------------------------+----------+----------+-----------+---------+
| Geometric Mean         | F        | 69       | 194       | 615     |
| Frequency (MHz)        |          |          |           |         |
+------------------------+----------+----------+-----------+---------+
| Dipole Factor          | K~d~     | -111.8   | -120.8    | -130.8  |
| (dBm-dBu)              |          |          |           |         |
+------------------------+----------+----------+-----------+---------+
| Thermal Noise (dBm)    | N~t~     | -106.2   | -106.2    | -106.2  |
+------------------------+----------+----------+-----------+---------+
| Antenna Gain (dB)      | G        | 4 \*     | 6 \*      | 10 \*   |
+------------------------+----------+----------+-----------+---------+
| Front-to-back ratio    | FB       | 10       | 12        | 14      |
| (dB)                   |          |          |           |         |
|                        |          |          |           |         |
| (ratio of forward gain |          |          |           |         |
| to maximum response    |          |          |           |         |
| over rear 180^o^)      |          |          |           |         |
+------------------------+----------+----------+-----------+---------+
| Downlead line loss     | L        | 1        | 2         | 4       |
| (for 50 ft/15 m. of    |          |          |           |         |
| coaxial cable (dB)     |          |          |           |         |
+------------------------+----------+----------+-----------+---------+
| System (receiver)      | N~s~     | 10       | 10        | 7       |
| noise figure (dB)      |          |          |           |         |
+------------------------+----------+----------+-----------+---------+
| Required receiver S/N  | S/N      | 15.2\*\* | 15.2\*\*  | 1       |
| ratio (dB)             |          |          |           | 5.2\*\* |
+------------------------+----------+----------+-----------+---------+
| Time variability       | dT       | 0\*\*\*  | 0\*\*\*   | 0\*\*\* |
| factor                 |          |          |           |         |
|                        |          |          |           |         |
| (90% availability)     |          |          |           |         |
| (dB)                   |          |          |           |         |
+------------------------+----------+----------+-----------+---------+
| Location variability   | dL       | 0        | 0         | 0       |
| factor                 |          |          |           |         |
|                        |          |          |           |         |
| (50% availability)     |          |          |           |         |
| (db)                   |          |          |           |         |
+------------------------+----------+----------+-----------+---------+

\* Antenna placement is assumed outdoors at 9 meters (30 feet).

\*\* The required S/N value stated in the *DTV Sixth Report and Order*
and OET Bulleting No. 69 is 15. That value was rounded from the 15.19
value set forth in the FCC Advisory Committee on Advanced Television
Service's (ACATS) *Final Technical Report* (October 31, 1995) at Table
5.1.

\*\*\* The time variability factor is defined as the difference between
the F(50,10) minus F(50,50), where these two values are determined from
the charts in Section 73.699 of the Commission's rules, 47 C.F.R.
§ 73.699. This factor is a function of the distance between the
transmitting and receiving antennas.

14. Using the factors in the above chart, the minimum signal level that
    needs to be present at the input terminal of a television receiver,
    to provide service is the sum of the thermal noise, the receiver
    noise figure, and the receiver signal-to-noise (S/N) ratio, that is:

Minimum receiver signal level R = N~t~ + N~s~+ S/N

for low and high VHF channels = -106.2 + 10 + 15.2 = -81.0 dBm

for UHF channels = -106.2 + 7 + 15.2 = -84.0 dBm

15. Considering the entire receiving system, the minimum field strength
    needed to be available at the antenna is the sum of the minimum
    signal level needed at the receiver, the downlead line loss, and the
    dipole factor, less the antenna gain:

Minimum field strength to receive service MFS = R + L + K~d~ -- G

for low VHF channels = -81.0 dBm + 1 + 111.8 -- 4 = 27.8 dBμV/m

for high VHF channels = -81.0 dBm + 2 + 120.8 -- 6 = 35.8 dBμV/m

for UHF channels = -84.0 dBm + 4 + 130.8 -- 10 = 40.8 dBμV/m

16. Rounding to the nearest decibel, we have 28, 36, and 41 dBu as the
    minimum field strength standards for channels in the low VHF, high
    VHF, and UHF channel bands, respectively. As indicated in the chart
    of planning factors, above, no adjustments were needed to compensate
    for time or location variability beyond that already afforded by
    F(50, 90) level of service.

B. Review of the DTV Field Strength Intensity Standards

17. Several parties commenting in the *Inquiry* indicate that the
    Commission should continue to determine whether a household is
    unserved based on the current assumed planning factors, which
    include an assumption that an outdoor stationary antenna is mounted
    at a height of 9 meters.[^28] The National Association of
    Broadcasters (NAB) states the assumptions made in the Commission's
    DTV planning factors and in the Longley-Rice model about household
    reception equipment are reasonable and realistic.[^29] In
    particular, NAB asserts that, as was the case for analog television,
    the Commission's digital transition proceeding has always assumed
    that consumers in fringe areas would use rooftop antennas that are
    properly oriented to achieve the best reception from the station in
    question.[^30] As a consequence, NAB reasons that broadcasters have
    built transmission systems based on these Commission assumptions and
    standards and, thus, it would now be unfair to assume, as a DTV
    planning factor, that viewers will use indoor antennas.[^31] Also,
    NAB contends that, because rooftop antennas provide much better
    service than indoor antennas, households have long used rooftop
    antennas to achieve over-the-air reception, particularly if the
    household is at some distance from the transmitting tower. It notes
    that rural households often rely on small towers -- with
    over-the-air antennas placed considerably higher than the assumed
    rooftop level -- to receive a strong signal from stations several
    dozen miles away.[^32] Additionally, NAB asserts that satellite dish
    antennas can only be used outdoors, usually atop a roof, and,
    therefore, it would be "egregiously discriminatory" for the
    Commission to conclude that while satellite subscribers are expected
    to rely on a rooftop antenna for their satellite reception, they
    cannot be expected to do the same to pick up over-the-air
    signals.[^33] The Consumer Electronics Association (CEA) submits
    that broadcast television households should have a right to a
    consistent definition of whether their households are considered
    served by a TV station.[^34]

18. In their comments, the ABC, CBS, and NBC Television Affiliate
    Association (Network Affiliates) state that the Commission's DTV
    planning factors established appropriate signal strength thresholds
    for reception of real-world DTV signals.[^35] These planning
    factors, Network Affiliates assert, contain a "safety margin" to
    ensure that quality DTV reception is achievable precisely where the
    Commission expects it to be, namely, in the replicated analog TV
    service area.[^36] With these considerations in mind, and realizing
    that satellite antennas must be mounted outdoors and must be
    oriented to the satellite for proper reception, the Network
    Affiliates contend that it would be "inappropriate to essentially
    penalize" local TV stations for those consumers who were only
    willing to install an indoor antenna (or an antenna that was
    incapable of being oriented to the desired signal), especially when
    those consumers are willing to take additional, necessary steps to
    obtain adequate satellite reception.[^37] Moreover, they state that
    real-world equipment, including fifth generation DTV receivers whose
    performance in terms of whether they are able to receive service
    does not vary by price, demonstrates that the Commission's current
    signal strength thresholds are more than adequate to receive a
    high-quality digital picture.[^38] The MSTV, the NAB and the Network
    Affiliates argue that there is no need for the Commission to
    consider modifying the inherent assumptions regarding DTV antenna
    receiving systems in the DTV planning factors and that it should
    recommend to Congress that the DTV signal strength standards remain
    the same for purposes of determining whether a household is
    "unserved" by a digital signal for purposes of 17 U.S.C.
    § 119(d)(10).[^39] CEA argues that it is not appropriate for the
    Commission to take into consideration that an antenna can be mounted
    on a roof or placed inside a home or can be fixed or capable of
    rotating. It submits rather that it is necessary and sufficient for
    the Commission to state that a given field strength, predicted or
    measured, at a known height above the location determines whether a
    household is served.[^40]

19. Other commenting parties assert that the planning factors should be
    substantially modified or are otherwise insufficient for use in
    determining household eligibility pursuant to SHVERA.[^41] EchoStar
    argues that the signal strength standard should be revised to
    account for DTV receiver performance, man-made noise, indoor antenna
    use, and the lack of rotation in outdoor antennas.[^42] It submits
    that the signal sensitivities of the current generation of receivers
    are worse than the signal sensitivities assumed in the DTV planning
    factors and that as a result many consumer DTV sets may not be able
    to display a DTV picture even when the signal strength meets the
    Commission's standards. EchoStar also argues that for the low VHF
    channels man-made noise was not adequately taken into account in the
    planning factors and that as a result the Commission did not build
    in a sufficient margin for noise when it set the signal strength
    standard for those channels. With regard to indoor antenna, EchoStar
    argues that an outdoor antenna is not practical for many households,
    particularly those located in apartment buildings. It further
    contends that even households with outdoor antennas often do not
    have rotating antennas or have a practical means of re-pointing
    their antennas "on the fly" to achieve optimum reception for every
    broadcast station in the market. EchoStar suggests that the
    Commission should take these factors into account and recommend
    modifications to the signal strength standard.

20. In the subsections below we examine the signal strength questions
    addressed in the SHVERA and other planning factor issues raised in
    the *Inquiry*. We will consider the comments above and our
    evaluations of the issues in these subsections in developing our
    recommendations to Congress on DTV signal strength standards, which
    are set forth at the end of this section.

1\. Antenna Gain, Orientation, and Placement

21. An antenna is the first element in the path that constitutes a
    household's TV receiving system. The antenna receives the
    electromagnetic energy of a television signal and converts it into
    electrical energy. The effectiveness of receiving antennas is
    determined both by factors intrinsic to the specific antenna design
    and by external factors. With regard to the former, antennas are
    designed with varying amounts of antenna gain or directivity. The
    greater the gain of a receiving antenna is, the greater the
    antenna's ability to capture weak signals. However, there is a
    significant tradeoff when incorporating additional gain in an
    antenna design. That is, designing an antenna with greater gain
    requires that it also be designed to have a narrower beamwidth.
    Beamwidth, in turn, refers to the antenna's angle of orientation
    within which the gain occurs. The narrower the beamwidth of a
    receiving antenna, the more critical it is to accurately aim the
    antenna directly at the source of the signal of interest. The signal
    strength of a transmission that is received by an antenna's main
    lobe beamwidth will be stronger than if that transmission was
    received from a direction outside that main lobe. With regard to
    external factors, considerations relating to antenna placement and
    orientation affect the ability of a household to receive an adequate
    DTV signal. For example, because structures located within the line
    of sight between the transmitter and the receiving antenna can block
    or weaken the strength of received signals, an outdoor antenna
    installation, such as upon a rooftop, will generally allow a
    stronger signal to be received by the antenna than will an indoor
    antenna installation. Thus, for households located in the same
    general area, an indoor antenna will generally need an antenna with
    greater gain than will a household in which the antenna is placed
    outdoors. If an antenna is oriented/directed so that its maximum
    gain is not focused on the desired TV signal, the received energy
    from that station's signal will be much lower.

22. Inherent in the Commission's definition of digital television
    service area are certain assumptions regarding the receiving
    antenna. For DTV, the Commission assumes that the receiving antenna
    is located outdoors at a height of 9 meters above ground.[^43] In
    addition, the Commission's procedures for evaluating DTV service
    areas set forth specific values for antenna gain that depend upon
    the specific DTV channel band, namely, 4 dB for low VHF, 6 dB for
    high VHF, and 10 dB for UHF and assume that the antenna is oriented
    in the direction which maximizes the values of the field strength
    received for the signal being measured.[^44]

23. In the *Inquiry*, we sought comment and information regarding the
    antenna equipment available to and used by consumers as a possible
    factor in the DTV signal availability standards. Consistent with the
    provisions of Section 339(c)(1)(B)(*i*), we asked whether there is a
    need to revise the standards by which adequate DTV network signals
    are deemed available to households in order to account for the facts
    that DTV antennas can be mounted on a roof or within a home and can
    be installed in a fixed position or in a mounting that allows them
    to be rotated. As required under Section 339(c)(1)(B)(iii), we also
    requested comment and information on whether a standard other than
    the presence of a signal of a certain strength should be used to
    ensure that a household can receive a high-quality picture using
    antennas of reasonable cost and installation. Specifically, we asked
    if the inherent assumptions regarding DTV antenna receiving systems
    should be modified or extended insofar as they relate to the proper
    determination of whether households are unserved by adequate
    broadcast DTV network signals and are thus eligible to receive
    distant DTV network signals from a satellite service provider. We
    requested that commenting parties provide information on the types
    of antennas that are in use currently, or soon to be available for
    outdoor or indoor residential use, including technical
    specifications (*e.g*., size, gain, beamwidth) and how those factors
    affect cost and deployment. Further, we requested information on the
    availability and cost of various devices that can be used to aim
    these antennas (*e.g*., rotors) toward DTV transmitters. In this
    regard, we requested comment on how the addition of a rotor would
    affect the size of an antenna system and thus the ability of
    consumers to mount an antenna indoors. We asked that commenting
    parties provide an evaluation of whether the use of an indoor
    antenna with or without a rotor would provide similar performance to
    that expected based on the Commission's assumed planning factors.

24. *Inquiry Record*. The parties commenting in the *Inquiry* who
    represent broadcast and consumer electronics interests generally
    state that the Commission should continue to determine whether a
    household is unserved based on the assumed planning factors,
    including the use of an outdoor stationary antenna mounted at a
    height of 9 meters. For example, the NAB states that broadcasters
    have built transmission systems based on the Commission's standards
    and it would be unfair to now assume that viewers will use indoor
    antennas.[^45] In a statement attached to the NAB's comments, the
    engineering firm of Meintel, Sgrignoli, and Wallace (MSW) argue that
    the planning factors for the DTV receive antenna setup are
    reasonable based on moderately priced equipment that is readily
    available to consumers in the marketplace.[^46] The Network
    Affiliates argue that it would be inappropriate to penalize local TV
    stations for consumers who are only willing to install an indoor
    antenna when the consumer is willing to take additional, necessary
    steps to obtain adequate satellite reception.[^47] Thus, in the
    Network Affiliates' view, there is no basis for modifying the
    inherent assumptions regarding DTV antenna receiving systems in the
    DTV planning factors.[^48] EchoStar and Paul Robinson, the General
    Manager of Robinson Telephone, take a different position, arguing
    that the antenna planning factors should be revised to take into
    account indoor antennas, with EchoStar adding that the lack of
    rotation capability in outdoor antennas should also be
    considered.[^49]

25. Looking first at the record on antenna performance, commenting
    parties representing the interests of broadcasters and the consumer
    electronics industry submit that reasonably priced antennas that
    exceed the gain and front-to-back ratios assumed in the planning
    factors are readily available.[^50] The Network Affiliates argue
    that the planning factors should consider the TV receiving antenna
    to be outside on the roof or adjacent to the house.[^51] They
    further submit that the antenna should be considered oriented to the
    desired signal, and if the desired stations are not located in the
    same direction, then the antenna should be considered orientable in
    the direction of the desired signal(s).[^52] The Network Affiliates
    submit that the equipment for a high quality outdoor antenna
    receiving system, including an eight-way bowtie-with-screen antenna
    and a rotor with remote control can be purchased for approximately
    \$100.[^53]

26. Jules Cohen, in an engineering appendix to the Network Affiliates
    comments, states that manufacturers' specified antenna gains vary
    from averages of 12 dB or more for UHF, mostly about 10 dB for high
    VHF, and 5-7 dB for low VHF.[^54] The NAB and the Network Affiliates
    submit that the best UHF antenna, considering both performance and
    value, is an eight-bay bowtie-with-screen antenna.[^55] The Network
    Affiliates state that an FCC study in 1980 determined that this
    design provides an average gain of 13.4 dB.[^56] They also state
    that antennas with higher average UHF gains are available, although
    they are slightly more expensive.[^57] The consulting engineering
    firm of du Treil, Lundin & Rackley (dLR) (in an attachment to MSTV's
    comments), the Network Affiliates and Viamorph each compiled data
    from several leading manufacturers of consumer television
    antennas.[^58] Their compilations show, in part, that Channel Master
    offers an eight-bay bowtie-with-screen UHF antenna, Model No. 4228,
    with an average gain of 12.0 dB; Winegard offers a UHF antenna
    designed for deep fringe areas, Model PR-9032, with a gain of 15.6
    dB; and Antennas Direct offers a long-range UHF antenna, Model 91XG,
    with a gain of 16.7 dB.[^59] The Network Affiliates indicate that
    the Channel Master 4228 retails for \$38.99 from Solid Signal
    (solidsignal.com); Winegard's PR-9032 retails for \$34.99 from Solid
    Signal; and Antenna Direct's Model 91XG sells for \$79
    (antennasdirect.com).[^60] Based on this information, the Network
    Affiliates submit that the Commission's DTV planning factor of 10 dB
    for UHF antenna gain is very conservative and can easily be achieved
    with readily available consumer antennas. [^61]

27. The Network Affiliates submit that the most recent study of VHF
    antennas of which they are aware was conducted by the Institute for
    Telecommunications Sciences (ITS), an agency of the Department of
    Commerce, in 1979. That study indicated that the average gain of an
    antenna for low VHF use was 4.43 dB and for high VHF band use was
    8.43 dB. The Network Affiliates note that these gain values exceed
    the DTV planning factor gain values of 4 dB and 6 dB,
    respectively.[^62] The Network Affiliates also state that currently
    there are a number of VHF antennas on the market that exceed the
    gain assumed in the DTV planning factors. They submit that these
    include the Antennacraft Model CS 1100, with an average gain in the
    low VHF band of 6.9 dB and an average gain in the high VHF band of
    9.6 dB; the Channel Master Model No. 3610, with an average gain in
    the low VHF band of 5.8 dB and an average gain in the high VHF band
    of 11.4 dB; and the Winegard Model HD4053P, with a gain in the low
    VHF band between 5.9 and 6.6 dB and in the high VHF band of between
    9.6 and 11.4 dB.[^63] The Network Affiliates state that the
    Antennacraft CS 1100 has a list price of \$96.08
    (antennacraft-tpd.com) and that Winegard's HD4053P retails for
    \$119.99 from Solid Signal.[^64] They submit that with antennas
    offering these levels of performance, it is apparent that the DTV
    planning factors of 4 dB gain for low VHF signals and 6 dB for high
    VHF signals are also very conservative and can easily be achieved
    with readily available consumer VHF antennas. The NAB submits that
    another option for consumers is the Winegard SquareShooter SS-2000,
    a small, attractive directional antenna with a preamplifier.[^65]
    The NAB states that while the manufacturer states that the antenna
    alone has a gain of 4.5 dB at UHF (below the planning factor
    assumption), the gain of combined setup with the preamplifier far
    exceeds the planning factors. It submits that the SquareShooter 2000
    is available for about \$98.99 from Solid Signal.[^66]

28. The Network Affiliates further submit that although combination
    VHF/UHF antennas do not generally perform as well as separate VHF
    and UHF antennas, there are consumer models available that exceed
    the assumed gains in the DTV planning factors. For example, they
    state that Winegard's Model D7084P has gain of from 6.2 dB to 7.6 dB
    in the low VHF band, from 10.8 dB to 12.0 dB in the high VHF band,
    and from 11.8 dB to 14.6 dB in the UHF band and that Antennacraft's
    Model HD1850 has an average gain of 6.2 dB in the low VHF band, 10.7
    dB in the high VHF band, and 10.0 dB in the UHF band.[^67] The
    Network Affiliates indicate that Winegard's HD7084 retails for
    \$127.99 from Solid Signal and Antennacraft's HD1850 has a list
    price of 174.97.[^68] They further note that even Channel Master's
    eight-bay bowtie-with-screen UHF antenna, Model No. 4228, has been
    measured by an independent engineering firm, Dielectric
    Communications, to possess an average gain of approximately 3.0 dB
    in the low VHF band, approximately 9.0 dB in the high VHF band, and
    approximately 15.0 dB in the UHF band (which exceeds the
    manufacturer's own specifications) and that it retails for \$38.99
    from Solid Signal.[^69]

29. The Network Affiliates state that such high-gain antennas are not
    appropriate for all receiving locations and that where signal
    strength is already adequate or nearly adequate, such a high-gain
    antenna could overload a receiver. They note that for those
    circumstances antenna manufacturers produce smaller antennas with
    less gain. They point out that CEA, in conjunction with
    Decisionmark, has established a website, AntennaWeb.org, that is
    designed to assist consumers in selecting an appropriate outdoor
    receiving antenna. The Network Affiliates submit that even if the
    gain of an antenna is less than the gain assumed in the planning
    factors, that does not mean that the planning factors are defective,
    because at locations where those antennas are appropriate the
    ambient signal strength will already exceed the thresholds set forth
    in the planning factors. [^70]

30. The Network Affiliates observe that, although it is not an element
    affecting the digital signal strength standards, the Commission did
    assume that TV receiving antennas would have a directional gain
    pattern in order to discriminate against off-axis undesired stations
    and thereby ameliorate interference.[^71] They note that the ATSC
    recommends the use of a directional gain antenna to enhance receiver
    performance with respect to multipath: "\[A\]n antenna with a
    directional pattern that gives only a few dB reduction in a specific
    multipath reflection can dramatically improve the equalizer's
    performance. Such modest directional performance can be achieved
    with antennas of consumer-friendly size, especially at UHF."[^72]
    The DTV planning factors account for this directionalization in the
    assumed front-to-back ratios of 10 dB for low VHF, 12 dB for high
    VHF, and 14 dB for UHF. The Network Affiliates indicate that it is
    common for readily available consumer antennas to meet or exceed
    these assumed front-to-back ratios. They state that, of the antennas
    mentioned above, the front-to-back ratio of Channel Master's
    eight-bay bowtie-with-screen UHF Model No. 4228 exceeds 19 dB at all
    UHF frequencies and is 24 dB at channel 43. Similarly, the
    front-to-back ratio of Winegard's UHF Model PR-9032 is 14 dB at
    Channel 14 and 20 dB at both channel 32 and channel 50. The Network
    Affiliates state that commonly available VHF antennas also appear to
    easily exceed the assumed front-to-back ratios for the low and high
    VHF bands. They state that Antennacraft's Model CS 1100 has a
    front-to-back ratio of 19.4 dB in the low VHF band and 17.6 dB in
    the high VHF band; and that the front-to-back ratio of Winegard's
    VHF Model HD4053P is 17 dB or greater across both the low and high
    VHF bands.[^73]

31. The Network Affiliates state that VHF/UHF combination antennas also
    greatly exceed the assumed front-to-back ratios for the low and high
    VHF bands and meet the assumed ratios for the UHF band. They
    indicate that the front-to-back ratio of Winegard's VHF/UHF
    combination antenna Model HD7084P is 20 dB or greater in the low VHF
    band, 15 dB or greater in the high VHF band, and is 11 dB at channel
    14 and 20 dB at both channel 32 and channel 50. They state that the
    front-to-back ratio of Antennacraft's VHF/UHF combination antenna,
    Model HD1850, is 20.2 dB in the low VHF band, 17.3 dB in the high
    VHF band, and 13.7 dB in the UHF band.[^74]

32. Jules Cohen, MSW, the NAB, and the Network Affiliates submit that in
    addition to selecting antenna with performance criteria that meet
    their needs, consumers can be expected to exert the same efforts to
    receive DTV signals that they have always been expected to exert to
    receive analog signals. They state that this may include the use of
    a rotor to properly orient the antenna to receive different signals
    if needed and, in fringe areas where signal strength is known to be
    weak, use of a low-noise amplifier (LNA) or "pre-amplifier."[^75]
    Jules Cohen, dLR, MSW, and the Network Affiliates report that there
    are many current offerings of moderately priced LNAs with signal
    amplification available in values between 18-30 dB and with noise
    figure values between 3-5 dB.[^76] For example, they observe that
    Winegard currently offers 16 different LNAs with gains ranging from
    17 dB to 29 dB and note that the Winegard Model AP-8275 provides an
    average gain of 29 dB for VHF and 28 dB for UHF with an internal
    noise figure of only 2.9 dB and 2.8 dB in those respective bands,
    with a retail price of \$77.99 from Solid Signal.[^77] Similarly,
    the Channel Master 7777 has an average gain of 23 dB for VHF and 26
    dB for UHF with internal noise figures of 2.8 VHF and 2.0 dB for
    those respective bands, and it retails for \$56.99 from Solid
    Signal.[^78] Also, Antennacraft offers an LNA with adjustable gain
    to prevent overload, Model 10G212, that provides an average gain of
    30 dB for both VHF and UHF with a noise figure of less than 4.0 dB
    for VHF and less than 3.5 dB for UHF, with a list price of
    \$33.63.[^79] The Network Affiliates identify Blonder Tongue and
    Advanced Receiver Research as additional LNA manufacturers. MSW
    submits that the ready availability of these preamplifiers provides
    a substantial "cushion" against the possibility of any losses not
    specifically accounted for in the planning factors.[^80] Jules Cohen
    states that a conservative choice of parameters to illustrate the
    advantage of using a pre-amplifier at the antenna would be:
    amplifier noise figure 5 dB, amplifier gain 20 dB and receiver noise
    figure of 12 dB.[^81] He further states that the resulting system
    noise figure would be 5.2 dB, which considering that the system
    noise figures in the planning factors are 10 dB for VHF and 7 dB for
    UHF, would provide an extra margin to minimize the impact of system
    mismatches.[^82]

33. With regard to proper orientation of antennas, EchoStar contends
    that even households with outdoor antennas often do not have
    rotating antennas or have a practicable means of re-pointing their
    antennas "on the fly" to achieve optimum reception for every
    broadcast station in the market.[^83] It states that in some markets
    not all of the network stations may be transmitting from the same
    site, so that there may be no single "optimal" pointing solution.
    EchoStar further contends that even households with antennas that
    are capable of rotating generally do not have the ability to adjust
    the orientation of their antennas "on the fly" so that for most
    purposes the antenna is non-rotating. In a statement appended to
    EchoStar's comments, the consulting engineering firm of Hammett &
    Edison, Inc. (H&E) claims a worst case loss scenario of 14 dB for a
    high-performance (*i.e.*, high-gain) antenna at UHF.[^84] H&E
    further states that it conducted a study using the Terrain
    Integrated Rough-Earth Model (TIREM) that found that the majority of
    all households in the United States are able to receive at least two
    analog TV stations of Grade B intensity and that, of those
    households, the majority receive at least one from an angle that
    differs by greater than 25^o^ from another station.[^85] As a
    result, it contends that almost all households will have impaired
    reception of at least one station. EchoStar believes that this
    analysis suggests that signal strength loss from the lack of a
    rotating antenna can be significant and should therefore be taken
    into account.[^86] It states that one way to do so would be to
    conduct further study to determine the "average" signal loss caused
    by the lack of a rotating antenna and to subtract that amount from
    the measured signal strength before comparing it to the Commission's
    signal strength standards.

34. On the other hand, dLR, the Network Affiliates, and the NAB argue
    that the Commission should continue to assume that DTV antennas are
    oriented towards the desired signal, and if the desired stations are
    not located in the same direction, that that antenna will be
    orientable in the direction of the desired signal.[^87] They argue
    that this assumption remains appropriate given the availability of
    reasonably priced antennas and rotors as described above. The
    Network Affiliates submit that the Electronics Technicians
    Association (ETA) showed in the Commission's proceeding in CS Docket
    No. 98-201 that the majority of home antenna systems in Putnam
    County, Indiana, a location representative of the outer reaches of
    the service areas of several broadcast stations, contain a rotor (in
    addition to a LNA) and that this is true even though homeowners in
    Putnam County can receive network programming from each of the four
    major networks from stations all located in Indianapolis.[^88] They
    argue that consumers can and will obtain rotors when they believe
    that they need them. They note statements by the ETA that rotors are
    economical (\$60-\$75) and do not require constant rotation and that
    "to circumvent the intent of the SHVA because the homeowner prefers
    not to invest in a rotor where needed is not right."[^89] The NAB
    argues that it would be discriminatory to assume that a DBS
    household's over-the-air antenna is improperly oriented when that
    same household's satellite antenna must be precisely oriented
    towards the satellite to get any service at all.[^90] It notes that
    the DTV transition has been premised on the assumption that viewers
    will use properly oriented antennas to receive digital TV
    signals.[^91]

35. The NAB states that, in most instances consumers can use a single,
    fixed antenna, because the TV transmitters in many markets are
    co-located. In such cases, there will be no need for a rotor. It
    states that in markets where TV towers are located at different
    sites, local electronics installers sometimes offer a special
    antenna designed to receive signals from two different directions,
    again without the need for a rotor. And NAB states that for those
    instances which differ from the situations just discussed, consumers
    can acquire, at a modest cost, a rotor that enables a rooftop
    antenna to be oriented to achieve the best signal from a particular
    station.[^92]

36. With regard to the availability of antenna rotors, the engineering
    statements and comments submitted by dLR and the Network Affiliates
    point out that many models, such as those sold by Channel Master,
    Antennacraft, Delhi (formerly Jerrold), and Radio Shack, are readily
    available. The comments also indicate that some of these rotors are
    available with a remote control so that the viewer can properly
    orient the antenna conveniently, from the couch or other
    location.[^93] The NAB and the Network Affiliates submit that prices
    for rotors range from \$68.99 for a Channel Master unit with remote
    control (CM 9521A, available from Solid Signal) to \$94.88 for an
    Antennacraft model (available at antennacraft-tpd.com).[^94]
    Viamorph, a manufacturer and licensor of antenna technologies,
    states that its research indicates that aiming a directional antenna
    is more difficult for digital TV signals than for analog TV signals
    and that a fixed digital TV antenna may not be a viable solution for
    many consumers.[^95] Viamorph submits that it is introducing a new
    class of antennas which it calls DiSA (Digital Smart Antenna) that
    automatically adjust their electrical shapes in response to changes
    in environment and signal conditions so as to maintain optimal
    performance. We also observe that CEA has issued a voluntary
    industry standard (CE-909) for TV antennas that automatically adjust
    their receive pattern to increase their gain in specific directions
    to receive individual signals. We have examined an antenna system
    constructed to this standard, the DTA 5000 (manufactured by DX
    Antenna Co.) which was small enough to be used indoors as well as
    outdoors, and have observed that it does appear to provide
    significantly improved reception of individual digital TV signals.

37. With regard to indoor antennas, EchoStar states that, because
    structures located within the line of sight between a TV transmitter
    and receiving antenna can block or weaken the strength of received
    signals, an outdoor antenna will generally allow a stronger signal
    to be received than will an indoor antenna.[^96] It argues that
    households in which the antenna is placed indoors will generally
    need an antenna with greater gain than will a household in which the
    antenna is placed outdoors. EchoStar argues, however, that because
    of limitations on the physical dimensions of indoor antennas, they
    have always had less gain than typical outdoor antennas. EchoStar
    notes that a review by H&E of the existing literature published as
    recently as 2005 and as far back as 1959 shows that indoor antenna
    gain is consistently about 9 dB or more below the values for outdoor
    antennas.[^97] EchoStar also submits that signal loss due to
    building penetration before it reaches an indoor antenna can be as
    great as 30 dB for VHF signals in a highly populated area like New
    York City, but this will vary depending on which floor of a building
    the indoor antenna is located.[^98] EchoStar argues that these
    factors mean that households relying on an indoor antenna for DTV
    reception are at a considerable disadvantage. It further argues that
    an outdoor antenna is not practical for many households,
    particularly those located in apartment buildings and that for these
    reasons the DTV signal strength standards should take into account
    indoor antenna use.[^99] Paul Robinson similarly argues that in a
    dense urban area most people may be living in multi-story apartment
    buildings or in condominium complexes and may be unable to install
    an external antenna.[^100] He urges that the planning factors should
    take these situations into account.

38. The NAB agrees that indoor antennas provide inferior reception
    capability to outdoor antennas.[^101] In this regard, it observes
    that indoor antennas are often non-directional and more prone to
    interference due to being mounted at lower heights and behind
    wall(s) thus reducing the ambient field strength available to the
    antenna.[^102] NAB also states that indoor antennas are usually
    nondirectional and therefore more prone to problems from both
    multipath and interference and are more easily affected by the
    proximity to viewers whose movement may contribute to altering its
    reception characteristics.[^103] The NAB and MSW further state that
    it is because rooftop antennas are so much better than indoor
    antennas that households have long used rooftop antennas to achieve
    reliable over-the-air reception, particularly where the households
    are at some distance from the TV transmitting tower.[^104] The NAB
    stresses that rural households often rely on small towers - with
    over-the-air antennas considerably higher than rooftop level - to
    receive a strong signal from stations several dozen miles away. This
    is in contrast to the case of indoor antennas, for which the NAB
    indicates that recent tests by Kerry W. Cozad show that some
    currently available indoor antennas deliver a weaker signal than a
    reference dipole antenna (*i.e.*, these antennas actually have
    negative gain).[^105] The Network Affiliates point out, however,
    that some indoor antennas currently available have an average gain
    of approximately 4 dB and, note that the Silver Sensor, with its
    short connection wire, does not have the line loss assumed in the
    planning factors.[^106]

39. Contrary to EchoStar, the NAB and the Network Affiliates argue that
    indoor antennas should not be considered in the DTV signal strength
    standards.[^107] They submit that it would be unfair to broadcasters
    to assume that viewers will use only indoor (or low-quality outdoor)
    antennas in determining whether DBS subscribers are eligible to
    receive retransmitted digital network signals. The NAB states that
    it is specifically because indoor antennas perform so poorly that
    they should not be considered for defining DTV service.[^108] It
    further states that introducing an assumption that consumers would
    use indoor antennas would be contrary to one of the most fundamental
    assumptions of the Commission\'s entire DTV planning process,
    leaving broadcasters in the position of having built a system to
    Commission specifications that the Commission would not deem as
    adequate because it is not designed to provide service to indoor
    antennas.[^109] The NAB and MSW also state that, had the Commission
    assumed use of indoor antennas in the planning the digital TV
    transition, that process would have been radically different, with
    stations needing enormously higher power levels to reach indoor
    antennas 50 to 60 miles away.[^110] They add that such higher power
    levels would have changed the interference calculations. The Network
    Affiliates similarly argue that it is critical to the Commission's
    plan to replicate analog TV service areas to presume that households
    will exert similar efforts to receive DTV signals as they have
    always been expected to do to receive analog TV signals.[^111]

40. *Evaluation*. After considering the above information, in response
    to Section 339(c)(1)(B)(iii) we conclude that the current DTV
    planning factor assumptions for antenna gain, orientation, and
    placement remain appropriate and should not be altered for the
    reasons discussed below. Following from that conclusion, we also
    find that the current signal strength standard for determining
    whether a household can receive a high-quality picture using
    antennas of reasonable cost and ease of installation remains
    satisfactory and that a different standard is not needed. With
    respect to Section 339(c)(1)(B)(i), we also specifically conclude
    that the digital television signal strength standards in the
    Commission's rules should not be modified to account for the fact
    that an antenna can be mounted on a roof or placed within a home and
    can be fixed or capable of rotating.

41. The record on the performance capabilities and availability of
    antenna receiving equipment indicates that there are a very large
    number of options for antennas that meet or exceed the gain and
    front-to-back ratio capabilities assumed in the planning factors. In
    particular, we observe that antennas that provide gain of 7 dB,
    11 dB, and 14 dB or more and front-to-back ratios of 19 dB, 17 dB,
    and 20 dB in the low VHF, high VHF, and UHF bands respectively are
    readily available in a variety of models and at a range of
    affordable prices, *i.e.*, from about \$35 to about \$100. These
    capabilities compare favorably to the respective planning factors
    gain values of 4 dB, 6 dB, and 10 dB and front-to-back ratios of 10
    dB, 12 dB, and 14 dB by a fair margin (these performance levels
    exceed the gain standards by 3 dB, 5 dB, and 4 dB and the
    front-to-back ratio standards by 9 dB, 5 dB, and 6 dB,
    respectively). In cases where additional margin in the received
    signal-to-noise ratio is needed, there are numerous models of
    low-noise amplifiers available. Similarly, we observe that there is
    a wide variety of models of antenna rotor devices available,
    including units with remote controls, at reasonable prices. As the
    Network Affiliates point out, the Commission has long recommended
    that households in outlying or difficult reception areas use
    equipment and mounting locations appropriate to their needs. This
    equipment can include separate UHF and VHF antennas, which generally
    provide better performance than a combination UHF/VHF antenna at
    little or no additional cost. Our own review of the websites of
    various TV receive system retailers also indicates that products
    with lower performance levels and prices that can meet many
    households digital TV receive system needs are readily available.
    Thus, it is clear that the availability of digital TV receive
    systems that meet or exceed the antenna performance planning factors
    is not a constraint on viewers ability to receive signals under the
    current noise-limited DTV field strength signal intensity standards.
    The parties commenting in our *Inquiry* did not specifically address
    the issue of ease of antenna installation. However, based on the
    experience of the Commission and its staff over many years we do not
    believe that ease of installation is generally a concern for
    households in installing the types of antenna needed for use with
    over-the-air DTV service. Those antennas are essentially of the same
    design and mounting configuration as those that have been used for
    analog TV service (antenna design depends on the desired frequency,
    gain, and front-to-back ratio characteristics, but not on the
    modulation type, *e.g.*, analog or digital, of the signals to be
    received). TV antennas can in almost all cases be installed by a
    household resident or, if the resident desires, a professional
    installer for a modest charge.

42. We recognize that in some situations the transmitters of digital TV
    signals that households may desire to view are located in directions
    that vary by more than the 25^o^ of main beam reception capability
    provided by typical TV antennas. In such cases the households need
    either a multiple direction antenna system or an antenna with a
    rotor that allows the single antenna to be re-oriented in the
    direction of the desired signal. We find that the signal strength
    standards do not need to be modified to account for situations where
    households need to be able to receive signals from multiple
    directions. We agree with dLR, the Network Affiliates, and the NAB
    that the digital TV planning model should continue to assume that a)
    digital TV antennas are oriented towards the desired station and b)
    if the stations that a household desires to view are not all located
    in the same direction, then the household employ an antenna that can
    be re-oriented in the proper direction to receive any such desired
    station at any given time. As supported by the pattern of antenna
    rotor use in Putnam County, Indiana that is described in the record
    of our *Inquiry*, we conclude that consumers will obtain and use
    rotors if they need them. Likewise, in the many instances where
    households view signals radiating from one particular direction
    only, we conclude that those households would not need a rotor and
    therefore would not install one. We recognize EchoStar's point that
    a large number of households might be able to better receive signals
    from stations transmitting from different directions, often from
    neighboring markets, if they used a rotor. We believe, however, that
    it is best left to individual households to determine whether
    signals emanating from different directions are sufficiently
    desirable to view and, thus, whether to install a rotor to enable
    their reception. In any case, where a rotor could assist in the
    reception of television signals for whatever reason, consumers are
    able now to obtain them readily at affordable prices. We also
    conclude that it would unnecessarily penalize broadcasters and
    distort the digital TV service planning model to reduce the assumed
    available DTV field strength by some factor based on a households'
    use of a rotor as suggested by EchoStar. We do not recommend such
    action.

43. We also find that it would not be appropriate to account for the use
    of indoor antennas in the DTV field strength signal standards for
    purposes of determining eligibility for reception of distant network
    signals. As observed by the commenting parties, the strength of
    signals available for indoor reception is lower due to signal
    attenuation caused by walls and other structural features and, in
    most cases, lower antenna height available indoors. The amount of
    signal attenuation indoors will depend on the material used in a
    building's construction and where the antenna is located within the
    building. In addition, the smaller antenna designs that are suitable
    for indoor use provide less gain than their outdoor counterparts.
    The differences in the indoor and outdoor reception conditions mean
    that service will be receivable in many areas with an outdoor
    antenna but not with an indoor antenna. We believe that it would be
    impractical to attempt to account for indoor reception conditions in
    the DTV planning factors. As NAB and MSW observe, the technical
    standards for the digital television service were established
    assuming use of outdoor antennas at 9 meters/30 feet height above
    ground and with the gain set forth in the planning factors. If DTV
    service were instead based on consideration of indoor reception,
    then the power levels needed to replicate stations' analog service
    at distances of 55-60 miles or greater would be substantially
    higher. For example, if the antenna difference were assumed to be -9
    dB, as suggested by EchoStar and H&E, for indoor antennas and
    building penetration loss were assumed to be a conservative 21 dB,
    then stations would need to transmit signals with an additional 30
    dB of power, or 1000 times the power now authorized for DTV
    stations.[^112] Such power levels are not practical as they would
    greatly increase the potential for interference between stations and
    pose power costs for stations that would likely be so high as to
    threaten the economic viability of many stations. In addition, as
    discussed more fully below in the section on the digital television
    measurement procedure, it is not practical or reasonable to specify
    an indoor reception situation as the signal level that is available
    indoors will vary significantly at different locations within a
    residence. For example, the signal level available near an
    unobstructed window is likely to be higher than that which is
    available in a basement or an interior room with masonry walls.

44. We therefore believe that the current DTV service and operating
    model that allows stations to replicate their analog service areas
    based on similar assumptions, *i.e.*, service to outdoor antennas at
    9 meters, remains the most appropriate plan for this service. As
    with analog TV, digital TV signals are receivable at many locations
    with an indoor antenna. As the distance between the DTV transmitter
    and receive locations increases, the received signal strength
    decreases and the opportunities for indoor reception decrease in the
    same manner as for analog service. We also believe that it would be
    impracticable to establish a regime whereby households with indoor
    antennas are subject to different signal strength standards than
    those with outdoor antennas. The difficulty would arise in setting
    and applying standards for situations in which a household could not
    use an outdoor antenna.

45. We recognize that there are instances such as those in which
    households are located in apartment buildings and condominium
    complexes where viewers may be unable to use an outdoor antenna.
    However, we find that commenting parties representing broadcast
    interests make a compelling point in their observation that
    satellite dishes likewise can not provide service indoors to such
    households. We anticipate that if a household were able to install a
    satellite dish outdoors, it could, in some instances, co-locate an
    effective broadcast receive antenna with that dish.

2\. Receiver Performance

46. At the other end of a household's TV receiving system path is the
    television receiver. This device receives the broadband electric
    energy that is taken from the air by the antenna and conveyed to it
    by the downlead connecting wire, selects the channel desired by the
    viewer, and processes the information on that channel to provide
    digital television and other services to the consumer. The desired
    channel is selected by the receiver's tuner section and then
    demodulated to produce the 19.4 mbps ATSC digital bitstream that
    carries the program and other information provided on the signal by
    the broadcast TV station. The performance of a digital television
    receiver with respect to reception of service for purposes of SHVERA
    eligibility determinations depends on its noise figure,
    signal-to-noise (S/N) ratio, and adaptive equalizer
    capabilities.[^113] Noise figure is a measure of the level of noise
    generated internally within the device.[^114] Signal-to-noise ratio
    is a measure of the receiver's ability to discern a desired digital
    television signal from other energy (noise) that is present in the
    signal's channel. The adaptive equalizer is a feature of a digital
    television receiver's tuner section that determines its ability to
    handle reflections of the desired signal. These reflections are also
    known as multipath signals and can be observed on analog television
    pictures as "ghosts."[^115] The noise figure and S/N measures are
    included in the DTV planning factors as indicated above. The
    planning factors assume use of a receiver that has noise figure
    levels of not more than 10 dB in the low and high VHF bands and 7 dB
    in the UHF band and that can provide service when the received S/N
    ratio is 15 dB or more. If the representative values of actual
    receiver noise figures and S/N ratios are different from those of
    the planning factors it could affect the minimum field strength
    needed for service. If the sum of these factors is greater or lower
    than that assumed in the planning factors, a higher field or lower
    field strength, respectively, would be needed for service. Adaptive
    equalizer performance is not included in the planning factors
    because it was assumed that the receiver designs for this feature
    would adequately handle multipath signals. However, adaptive
    equalizer performance did become of concern more recently when it
    was determined that multipath was a larger challenge than initially
    anticipated and that a high level of ability to cope with multipath
    signals is important to reception of DTV signals.

47. In the *Inquiry*, as directed by Section 339(c)(1)(B)(v) we
    requested comment and information on whether there is a wide
    variation in the ability of reasonably priced consumer digital
    television sets to receive over-the-air signals, so that at given
    signal strengths some sets are able to display high-quality pictures
    while other sets cannot, and if so, whether this variation is
    related to the price of the television set. As further directed by
    Section 339(c)(1)(B)(v), we also requested comment on whether such
    variation should be factored into setting a standard for determining
    whether a household is unserved by an adequate digital signal. In
    considering these questions, we note that the nature of digital
    television operation is such that a receiver will provide a
    high-quality picture (consistent with its display capabilities) at
    all signal levels at or above its threshold of service.[^116] When
    the received signal/field strength falls below the minimum service
    threshold there is a very sudden loss of service that occurs over a
    signal strength change of less than 1 dB. This sudden loss of
    picture service, which first appears as blocking and freezing of
    portions of the image, is called the DTV "cliff effect." This
    operating characteristic is in contrast to analog TV service in
    which picture quality degrades gradually as signal strength
    declines. Thus, we will assume in our evaluation of digital
    television receiver performance that picture quality remains high at
    all signal/field strength levels above the minimum threshold needed
    for service.

48. In the *Inquiry*, we specifically requested that commenting parties
    provide information regarding the sensitivity of various receivers
    and their interference rejection capability. We asked that this
    technical information be accompanied by price data and analysis
    regarding the correlation between performance and price. Finally, we
    asked if there are significant differences in digital receiver
    performance quality and, if so, should those differences be factored
    into the determination of whether a household is unserved by an
    adequate digital signal. The Commission's Laboratory staff also
    undertook a technical measurement study of the performance
    capabilities of a sample of the digital television receivers
    currently on the market, looking at noise figure, S/N/ ratio,
    adaptive equalizer/multipath handling performance, and price.

49. *Inquiry Record*. With regard to DTV receiver noise figure
    performance, dLR states that it has not independently tested a
    representative sample of DTV receivers for their noise figure
    performance and assumed that information would be developed from the
    Commission's receiver study in this matter.[^117] MSW and the NAB
    submit that while there is little published data about receiver
    noise figures, consumers can, in any event make the noise figure of
    a receiver irrelevant by employing an inexpensive
    preamplifier.[^118]

50. Concerning the DTV receiver S/N ratio, dLR states that laboratory
    measurements by Bouchard, *et al*., of the Communications Research
    Center Canada (CRC) in late 2000 (Bouchard study) demonstrate S/N
    levels consistent with the Commission's assumed value of 15.2 dB for
    this planning factor.[^119] The measurements in this study were
    conducted on a sample of six DTV receivers manufactured in the
    period 1999-2000. For a weak desired signal, the study found a S/N
    range or 15.3 dB to 17.8 dB, with a median S/N of 15.6 dB. The five
    best out of the six had a S/N of 15.3 dB to 16.6 dB with a median
    S/N of 15.4 dB.[^120] dLR further states that laboratory
    measurements by the CRC on a Zenith fifth generation DTV receiver in
    September 2003 also show S/N measurement results that are consistent
    with the Commission's planning factor value.[^121] dLR submits that
    these results show a measured S/N of 15.9 dB in the presence of a
    weak signal level, which is within .7 dB of the planning factor
    value and indicates that the latest generation of DTV receivers will
    perform in line with those of earlier manufacture.

51. EchoStar argues that the DTV signal strength standards should be
    revised upwards because the signal sensitivities of the current
    generation of consumer DTV receivers can be significantly worse than
    the signal sensitivities, *i.e.*, S/N ratio plus noise figure,
    assumed in the planning factors for UHF and VHF reception.[^122] It
    argues that as a result of this difference in performance versus
    assumption, many consumer DTV sets may not be able to display a DTV
    picture even when the signal strength meets the Commission's
    standards. In support of EchoStar's position, H&E evaluated five DTV
    receivers for sensitivity in comparison to the DTV planning factor
    values.[^123] H&E submits that its results show that the measured
    sensitivities range as much as 6.6 dB higher than the planning
    factor values of -81.4 dBm and -84.4 dBm, that the receivers
    differed in sensitivity by 2-6 dB under favorable field conditions,
    *e.g.*, no multipath signals, and the average receiver in its study
    was 2.6 dB less sensitive than the planning factor value. In its
    reply comments, ATI points out that the H&E study considered older
    receivers that did not conform to the ATSC A/74 receiver performance
    standards or incorporate current models of VSB demodulators and so
    it is not surprising that the receivers H&E tested suffer from the
    shortcomings that the fifth generation of VSB demodulators was
    designed to resolve.[^124]

52. EchoStar and H&E submit that multipath handling capability can
    affect a digital television receiver's ability to provide
    service.[^125] They state that multipath can be measured and its
    severity can be expressed as a signal strength penalty caused by the
    adaptive equalizer in a receiver attempting to compensate for the
    multipath. H&E states that a receiver's adaptive equalizer, in
    attempting to compensate for the multipath will increase the
    system's noise level at the frequencies of compensation. H&E submits
    that at a good receiver location with little multipath, the adaptive
    equalizer tap energy might be about -10 dB, corresponding to a white
    noise penalty of less than 0.5 dB and that at a poor location the
    white noise penalty may exceed 2 dB. H&E further states that
    laboratory tests by others showed that receiver sensitivity
    decreased on the order of 0-5.3 dB in the presence of
    multipath.[^126]

53. Other commenting parties generally observe that in the early stages
    of the DTV transition, multipath was found to be much more difficult
    for digital TV reception than it was for analog TV reception. dLR,
    MSW, the NAB and the Network Affiliates state that the fifth
    generation DTV receivers now commercially available in integrated
    sets from manufacturers such as LG and Zenith have made substantial
    improvements in equalizer architecture and can now handle 50
    microsecond pre-ghosts and 50 microsecond post-ghosts.[^127] dLR
    submits that a paper by Tim Laud of Zenith reports laboratory
    results demonstrating fifth generation equalizer capability to
    handle ghosts of up to 50 microseconds and at a level of 100% (that
    is, the ghost reflection would be at the same level as the principal
    signal).[^128] dLR, MSW, and NAB note that Tim Laud's paper also
    reports on field tests on fifth generation receivers in Washington,
    DC, Ottawa, Canada, and Baltimore, MD, where significant
    improvements in performance at known "difficult" locations were
    demonstrated. dLR states that in these field tests, fifth generation
    receivers showed improvements ranging from an elimination to near
    elimination of failures (in the Ottawa and Baltimore tests) to a
    reduction in failures by a factor of three (in the Washington
    tests). ATI, a manufacturer of electronic components including DTV
    receiver chips, recommends that in evaluating multipath, the
    Commission specify the multipath field ensembles set forth in the
    ATSC's "A/74 Recommended Practice: Receiver Performance Guidelines."
    It submits that, in contrast to the field ensembles, the "laboratory
    ensembles" referenced in that document do not provide an adequate
    basis for predicting how well a receiver will perform in the
    field.[^129]

54. The Network Affiliates submit that because multipath is not a
    function of signal strength *per se* and because current fifth
    generation receivers can handle multipath even in generally poor
    reception conditions, the Commission's DTV planning factors do not
    need to be adjusted to account for multipath by increasing the value
    of the minimum field strength assumed to be needed to receive
    service.[^130] The Network Affiliates state that the effects of
    multipath can be mitigated greatly, if not wholly, by the use of the
    latest generation receiver, by the use of an outdoor antenna raised
    to 9 meters/30 feet that will place the antenna above the principal
    multipath reflectors (*e.g.*, moving vehicles and neighboring
    residences), and by the use of highly directional antennas with high
    front-to-back ratios, properly oriented to the strongest desired
    signal.[^131] They point out that the ATSC has stated that "\[A\]n
    antenna with a directional pattern that gives only a few dB
    reduction in a specific multipath reflection can dramatically
    improve the equalizer's performance. Such modest directional
    performance can be achieved with antennas of consumer-friendly size,
    especially at UHF."[^132] Further, the Network Affiliates observe
    that there is no principled basis to include multipath in the
    distant signal eligibility standards since there still remains no
    objective means to predict or evaluate multipath at any particular
    location or to evaluate the impact of multipath on local television
    service generally.

55. ATI submits that the current DTV receiver marketplace offers
    end-users superior performance that is highly affordable, with
    market trends projecting increasing affordability and performance as
    manufacturers integrate the latest generations of DTV receiver chips
    into their products.[^133] ATI and the Network Affiliates state that
    variations in DTV set prices should play no role in determining
    whether a household is unserved by an adequate DTV network
    signal.[^134] They state that there is as yet very little consumer
    penetration of DTV receivers and that most households will therefore
    have or will acquire DTV receivers with integrated tuners
    incorporating the latest generational chip design (fifth generation
    or later), including adaptive equalizers with superior multipath
    handling performance capabilities. ATI states that neither price nor
    brand name indicates to consumers the performance of DTV receivers
    and using the best chips does not necessarily cost more.[^135] It
    submits that as a result, consumers lack sufficient information for
    purchasing products based on DTV receiver performance. CEA submits
    that in a market guided by competition and not Government
    intervention, it should be expected that there will be products that
    optimize for different parameters.[^136] CEA states that these
    variations are relatively small, as every manufacturer is motivated
    by competition to build good receivers, but the variations still
    serve the market. For example, it states that a DTV receiver that
    has relatively poor weak signal reception as compared to every other
    receiver in the market might have excellent selectivity and prove to
    be the ideal receiver for a particular location with closely packed
    channels. Conversely, CEA states that even if the Commission were to
    determine that there is very little variation in the ability of
    existing DTV sets to receive over-the-air signals, those same sets
    when connected to the many different available antennas and placed
    in the infinitely complex RF environment will certainly demonstrate
    a wide variation in reception capability.

56. The Network Affiliates submit that with digital tuners manufactured
    in mass quantities to satisfy the Commission's digital tuner
    mandate, the cost of an integrated DTV set is not particularly
    dependent on the cost of the generation of chip design (for example,
    fourth generation vs. fifth generation).[^137] Instead, they argue
    that DTV set prices are largely dependent on features such as ATSC
    format/resolution capabilities (standard definition, enhanced
    definition, and high definition), screen size, screen technology
    (CRT, plasma, LCD, DLP), contrast ratio, and integration of other
    functions such as digital video recorders. The Network Affiliates
    submit that a survey of the Sharp "Aquos" and LG websites revealed
    no difference in the type of ATSC tuner included in integrated DTV
    sets within each manufacturer's product lines. They state that it
    would be inconsistent with the principal of localism and the
    objective standards Congress has always imposed on the "unserved
    household" definition to permit a satellite carrier to deliver a
    duplicating distant network signal to a household merely because the
    household had purchased, probably unknowingly, an inferior DTV set.
    They note that the current analog "unserved household" definition is
    not dependent on whether a household buys a \$59 13-inch television
    set or a \$400 27-inch set. They state that there is no reasonable
    basis to make such a distinction in the digital context.

57. *FCC Laboratory Receiver Study*. In order to obtain additional
    information on the performance of DTV receivers, the Commission's
    Laboratory conducted a technical measurement study (FCC Study) of a
    sample of 28 DTV receivers currently available on the market.[^138]
    The objectives of this study were to provide empirical information
    on the minimum signal level needed by consumer DTV receivers to
    provide service and whether the minimum signal level needed to
    provide service varies across DTV receivers by price. It also
    examined these receivers with respect to their S/N ratios, inferred
    noise-figures, and performance in the presence of multipath
    reflections using 47 of the 50 ATSC recommended difficult reflection
    "captures," or "ensembles."[^139] Tests were performed on three TV
    channels (channels 3, 10, and 30) in order to evaluate performance
    in the low VHF, high VHF, and UHF bands, respectively. The study
    receiver sample consisted of 28 products in two categories,
    set-top-boxes (STBs) and integrated DTV receivers. STBs were
    included because connection of an STB to an existing television set
    represents the lowest-cost alternative for DTV reception. All
    receivers were standard, off-the-shelf consumer products currently
    on the market and were provided on our request by their
    manufacturers. In examining the components of DTV receiver
    performance, the study considered that the minimum signal level
    needed to receive service is determined by the combined influence of
    the effective internal noise created by a receiver's internal
    circuitry (noise figure), signal-to-noise ratio (also termed white
    noise S/N threshold), and thermal noise, as included in the DTV
    planning factors. The minimum signal level needed to receive service
    is the threshold level at which errors become visible in the
    displayed picture, *i.e.*, threshold of visibility (TOV). Thus, we
    have:

*Minimum Signal at TOV (dBm) = Thermal Noise (dBm) + Noise Figure (dB) +
Required CNR (dB)* [^140]

58. The receivers were measured in the presence of conditions of white
    noise and of the multipath reflections indicated above. The results
    were reported by category (STB or integrated receiver) and price
    range (\$370 - \$1000, \$1001 - \$2000, and \$2001 - \$4200). Brands
    and model numbers were not reported. The results of this study are
    described below.

59. The summary results for the minimum signal level factor over all
    samples in the white noise conditions are shown in Table 1:

  ------------------------------------------ -------- --------- ---------
  **MINIMUM SIGNAL LEVEL AT TOV**            **Chan   **Chan    **Chan
                                             3**      10**      30**

  Planning factor values (dBm)               -81.0    -81.0     -84.0

  Median across all receivers (dBm)          -82.2    -83.2     -83.9

  Difference from OET-69 planning factors    -1.2     -2.2      0.1

  Deviations of receivers from median (dB)                      

  \--Best performing receiver (dB)           -2.5     -1.7      -1.4

  \--Worst performing receiver (dB)          12.5     4.3       2.5

  \--90^th^ percentile receiver (dB)         5.1      3.1       1.3

  Standard deviation (dB)                    3.7      1.6       0.9

  Total span from worst to best receiver     15.0     6.0       3.9
  (dB)                                                          
  ------------------------------------------ -------- --------- ---------

*Table 1 Statistics of Minimum Signal Level at TOV*

60. The median minimum signal levels for the study sample were slightly
    better - by 1.2 dB and 2.2 dB, respectively -- than the low-VHF and
    high-VHF planning factor value (-81.0 dBm) and closely matched the
    UHF planning value (-84.0 dBm). At low VHF, only 21% of the tested
    receivers performed more poorly in minimum signal level than the
    performance measures modeled in OET Bulletin No. 69 by an amount
    exceeding 1 dB, the approximate tolerance of the measurements.[^141]
    At high VHF and UHF, this figure was 11% and 18% respectively. The
    variation among receivers at low VHF was fairly large, with a 3.7 dB
    standard deviation. The two receivers exhibiting the poorest
    performance were at levels 10.6 dB and 12.5 dB worse than the
    median. These two receivers, both the same brand, were responsible
    for much of the variability and omitting them from the results
    reduces the low VHF standard deviation to 2.3 dB. The third worst
    performer at low VHF was 6.7 dB above the median. 89% of the
    receivers (all but three) were within 5.1 dB of the median at low
    VHF.

61. The performance results for the individual receivers are shown in
    Figure 1:

![](media/image2.wmf){width="6.497916666666667in"
height="4.254166666666666in"}

Figure 1. Measured Minimum Signal Level at TOV on Three Channels[^142]

62. Looking at the variation of the minimum signal level factor under
    the benign conditions by product category and price, as shown in
    Table 2 the FCC Study found:

+----------------------------------------------+------+-------+-------+
| **MINIMUM SIGNAL LEVEL AT TOV**              | **   | *     | *     |
|                                              | Chan | *Chan | *Chan |
| **(difference from the median by category    | 3**  | 10**  | 30**  |
| and price)**                                 |      |       |       |
+----------------------------------------------+------+-------+-------+
| Difference of Set-Top Boxes from Overall     | 2.0  | 0.5   | 0.7   |
| Median (dB)                                  |      |       |       |
+----------------------------------------------+------+-------+-------+
| Difference of Low-Price DTVs from Overall    | -1.1 | -0.2  | -0.2  |
| Median (dB)                                  |      |       |       |
+----------------------------------------------+------+-------+-------+
| Difference of Medium-Price DTVs from Overall | 0.0  | 0.5   | 0.0   |
| Median (dB)                                  |      |       |       |
+----------------------------------------------+------+-------+-------+
| Difference of High-Price DTVs re Overall     | -0.7 | -0.3  | 0.0   |
| Median (dB)                                  |      |       |       |
+----------------------------------------------+------+-------+-------+

*Table 2 Product-Type Variations of Minimum Signal at TOV*

63. This chart shows that the observed variations in minimum signal
    level across product and price categories were very small. The
    category medians for high VHF and UHF differ from the overall median
    by less than 1 dB and for low VHF differ by only 2.0 dB. At low VHF
    the median performance of the set-top boxes was 2.0 dB worse than
    the overall median of all receivers and the best median performance
    was achieved by the low-price DTV receiver category, which slightly
    outperformed the medium and high-priced categories. At low-VHF, the
    median of the highest priced sets was only 0.7 dB better than the
    overall median. In the high VHF and UHF bands the performance
    differences from the overall median were even less. Most of the
    differences in median values between categories are so small as to
    be considered insignificant. We believe that even the largest of
    these differences would affect perceived performance only in
    locations where the signal margin was very small and in the general
    case would not be noticeable to consumers at all.

64. The FCC study found that the white-noise S/N threshold for the
    median receiver in the sample was 15.3 dB, only 0.1 dB above (worse
    than) the planning factor value. The white-noise S/N threshold
    results are summarized in Table 3:

  ------------------------------------------------------------ -----------
  **WHITE NOISE S/N THRESHOLD**                                

  Planning Factor Value (dBm)                                  15.2

  Median across all receivers (dBm)                            15.3

  Difference from OET-69 planning factor                       0.1

  Deviations of receivers from median (dB)                     

  \--Best performing receiver (dB)                             -0.4

  \--Worst performing receiver (dB)                            0.5

  \--89th percentile receiver (dB)                             0.3

  Standard deviation (dB)                                      0.2

  Total span from best to worst receiver (dB)                  0.8[^143]
  ------------------------------------------------------------ -----------

*Table 3 Statistics of White Noise Threshold*

65. These results show that the variations in S/N performance among
    receivers is quite small, with the standard deviation of the S/N
    measurements across all of the sample receivers amounting to only
    0.2 dB. The total range from best to worst performing receiver was
    0.8 dB, with the worst performing receiver only 0.5 dB above the
    median performance. Similar lack of variation in S/N performance was
    found with respect to price, as shown in Table 4. The median
    performance of the least expensive receivers, the STBs, was only 0.1
    dB worse than the overall median. The median low-cost and mid-cost
    integrated sets performed at the median, while the median high-cost
    integrated set performance is only 0.2 dB better than the overall
    median.

  ---------------------------------------------------------------- ------
  **WHITE NOISE THRESHOLD**                                        

  Difference of Set-Top Boxes from Overall Median (dB)             0.1

  Difference of Low-Price DTVs from Overall Median (dB)            0.0

  Difference of Medium-Price DTVs from Overall Median (dB)         0.0

  Difference of High-Price DTVs from Overall Median (dB)           -0.2
  ---------------------------------------------------------------- ------

*Table 4 Product-Type/Price Variations of White Noise Threshold*

66. The study derived the receivers' inferred noise figure performance
    from the measurements of minimum signal level and S/N level under
    benign conditions and using -106.2 dBm as the value for thermal
    noise. The inferred noise figure values are shown in Table 5.

  --------------------------------------------- -------- -------- --------
  **NOISE FIGURE**                              **Chan   **Chan   **Chan
                                                3**      10**     30**

  Planning Factor Values                        10       10       7

  Median across all receivers (dBm)             8.8      7.6      6.9

  Difference from OET-69 planning factors       -1.2     -2.4     -0.1

  Deviations of receivers from median (dB)                        

  \--Best performing receiver (dB)              -2.5     -1.3     -1.3

  \--Worst performing receiver (dB)             12.2     4.5      2.6

  \--89th percentile receiver (dB)              4.5      3.3      1.2

  Standard deviation (dB)                       3.6      1.6      0.9

  Total span from worst to best receiver (dB)   14.7     5.7      3.9
  --------------------------------------------- -------- -------- --------

*Table 5 Statistics of Receiver Noise Figure*

67. These data show that the noise figures for the currently available
    receivers in the FCC study are generally better than the planning
    factor values by 1 or 2 dB at low and high VHF and are the same as
    the planning factor value at UHF. There is considerable variation in
    the sample receivers' noise figure performance at low VHF, with a
    standard deviation of 3.6 dB and with two receivers performing at
    levels 10.3 dB and 12.2 dB worse than the median. However, 89% of
    the receivers (all but three) were no more than 4.5 dB above (worse
    than) the median performance at VHF.

68. As shown in Table 6, the observed variations in noise figure with
    product category and price were small, with the category medians
    differing from the overall median by less than 1 dB for channels at
    high VHF and at UHF, but were slightly larger at low VHF. At low VHF
    the median performance of set-top boxes was 1.7 dB worse than the
    overall median of all receivers, and the median performance of the
    highest priced TV category was 0.8 dB better than the median. The
    best median noise figure, 1.4 dB better than the overall median,
    occurred in the lowest priced integrated receiver category. Such
    differences as shown in Table 6 are likely to influence performance
    only in locations where the signal margin is very small and
    generally would not be noticeable to consumers.

  ------------------------------------------------- -------- -------- --------
  **NOISE FIGURE**                                  **Chan   **Chan   **Chan
                                                    3**      10**     30**

  Difference of Set-Top Boxes from Overall Median   1.7      0.1      0.6
  (dB)                                                                

  Difference of Low-Price DTVs from Overall Median  -1.4     -0.1     0.1
  (dB)                                                                

  Difference of Medium-Price DTVs from Overall      0.0      0.4      -0.1
  Median (dB)                                                         

  Difference of High-Price DTVs from Overall Median -0.8     -0.3     0.0
  (dB)                                                                
  ------------------------------------------------- -------- -------- --------

*Table 6 Product-Type/Price Variations of Receiver Noise Figure*

69. Finally, measurements of the performance of the sample DTV receivers
    in the presence of the 47 multipath ensembles are shown in Figure
    2:[^144]

![](media/image3.wmf){width="6.497916666666667in"
height="4.247916666666667in"}

> *Figure 2 Performance against 47 RF Captures*

70. Unlike the results for white noise performance, the results of
    testing against the RF captures were heavily clustered into two
    performance tiers.[^145] The better performers successfully played
    29 captures without error and about 37 captures with two or fewer
    errors. The lower tier performers successfully played about 7
    captures without error and about 9 with two or fewer errors. Except
    for receivers D1 and L2, all results fall within ±2 captures of one
    of these nominal results. Receivers D1 and, perhaps, L2 appear to
    represent an additional performance level slightly above the lower
    tier. The upper tier performers provide a significant improvement in
    the ability to handle the most difficult multipath conditions.[^146]
    The tested receivers in this tier are known to include the latest
    generation of demodulator chips from at least two of the major DTV
    chip manufacturers. The results on Figure 2 are summarized in Table
    7.

  ------------- ----------- -------------------- -------------------------
                Number of   Number of Captures   Number of Captures Played
                Consumer    Played with No       with No More Than 2
                Receivers   Errors               Errors

  Lower Tier    16          7 ±2                 9 +2/-1

  Lower Tier+   2           8 and 12             14 and 16

  Upper Tier    10          29 ±2                37 ±2
  ------------- ----------- -------------------- -------------------------

Table 7 Number of Captures Successfully Played By Each Performance Tier
(Out of 47 Captures)

71. Looking next at the variation of multipath handling performance with
    product type and price, the FCC Study found that while none of the
    STBs, which are all of older design, perform at the upper tier
    level, upper and lower tier performing products appear in all three
    price categories of integrated receivers. This suggests that
    multipath handling performance is not a function of price. Among the
    integrated receivers, the study found that introduction dates in or
    after March 2005 were consistent with the likelihood of including
    newer technology. Among the tested receivers that were introduced on
    or after March 1, 2005, 48% were found to perform at the upper tier
    level. The study also notes that it is probable that some of the
    products introduced in this time frame carried over
    tuner/demodulator designs from a previous generation.

72. In reviewing these results, the FCC Study also considered that there
    might be some reason to expect that improvements in multipath
    performance - which is achieved in part by increasing the number of
    taps in the demodulator's equalizer circuit - might come at the
    expense of a reduced white noise threshold, because the additional
    taps could be expected to add noise that is related to carrier
    amplitude.[^147] Figure 3 shows measurements of white noise
    threshold plotted against multipath performance as measured by the
    number of RF captures (out of 47) that were successfully played
    without error. The lower tier of multipath performers (presumably
    containing earlier generation VSB decoders) had a median S/N
    threshold of 15.3 dB, slightly worse than the 15.2 dB threshold
    achieved by the ACATS Grand Alliance prototype receiver. The 15.1 dB
    median S/N ratio for the upper tier of multipath performers suggests
    that the characteristic of a worsening of S/N ratio as a trade-off
    for multipath no longer occurs.

![](media/image4.wmf){width="6.497916666666667in"
height="4.209027777777778in"}

*Figure 3 White Noise Threshold Versus Multipath Performance*

73. *Evaluation*. Based on our evaluation of both the *Inquiry* record
    and the FCC study, we conclude that neither the S/N ratio nor the
    receiver noise figure values in the DTV planning factors should be
    modified in determining the DTV field signal strength standards to
    be used for determining whether a household is eligible to receive
    retransmitted network DTV signals from a satellite service. In
    answer to Section 339(c)(1)(B)(v), we see no significant variability
    in the ability of reasonably priced consumer digital television sets
    to receive over-the-air signals in the high VHF and UHF bands such
    that some sets are able to display high-quality pictures while
    others cannot, and the variation that is present does not appear to
    be closely related to price. We note that in the low VHF band, there
    were two receivers that were significant outliers and a third
    receiver that was 6.7 dB above the median. We find that this few
    number of receivers with high low-VHF thresholds does not obviate
    our general conclusion that price is not a factor in the
    availability of DTV receivers that are able to display high-quality
    pictures.

74. We stated earlier that picture quality does not depend on the level
    of signal strength. Rather, the importance of the level of signal
    strength is simply whether service can be received, and the factors
    that determine that level are a receiver's S/N ratio and noise
    figure. Our FCC study results indicate that currently available DTV
    receivers are generally able to provide service with signals at
    levels very close to those assumed in the planning factors and in a
    few cases with signals at lower levels. We did find some variation
    in the reception performance with respect to the minimum signal
    level needed to provide service, but this was mostly at low VHF. In
    addition, H&E reported some receivers that need higher minimum
    signal levels to provide service. We do not view with concern those
    products needing higher minimum signal levels because it is apparent
    that the greater portion of products perform generally on a par with
    the planning factor value. Given that a large number of receivers
    performed well at signal levels at or close to the minimum signal
    level assumed by the planning factors, we do not believe that there
    are any technical difficulties in providing performance that meets
    the planning factor target. We believe that it is best to rely on
    market forces to determine whether those products or perhaps others
    performing at similarly high threshold levels remain available to
    consumers. At high VHF and UHF, the variation in reception
    performance among the receivers in our FCC study was small.

75. As indicated above, we also find no indication that increasing price
    levels are associated with improved minimum signal level
    performance. With the exception of set-top boxes, in fact, it
    appears that there is very little relationship between price and the
    minimum signal level needed to provide service. Because the set-top
    boxes studied, and indeed all of those now on the market, are of
    older designs, we believe that their general design, rather than
    their price, is the reason for their somewhat lower performance.
    Thus there do not appear to be any technical reasons that would
    impede the economical manufacture of products that perform at the
    expected minimum signal levels currently assumed in the planning
    factors for the DTV field strength standards.

76. The information on receiver signal-to-noise ratios and noise figures
    provided in the *Inquiry* record and from our study indicate
    performance levels consistent with the minimum signal level
    performance discussed above. This is reasonable given the close
    relationship of the three measures. It appears that most receivers
    now on the market exhibit S/N performance within levels very close
    to the 15.2 dB level assumed in the planning factors, and a few
    perform slightly better. Again, we do not view those products that
    are 5 dB or more above the planning factor value for minimum signal
    level to receive service as an indicator of a deficiency in the
    planning factor value, given that so many products do perform at or
    near the expected level. From our FCC study, it appears that most of
    the variation in the minimum signal level needed to provide service
    is the result of differences in receiver noise figures rather than
    S/N ratio. The noise figure variations were larger than the minimum
    S/N ratio variations by factors ranging from 3.9 dB, in the UHF
    band, to 14.7 dB in the low VHF band.

77. We conclude that it is not necessary to augment the DTV receiver
    planning factors with an additional factor for multipath. As
    EchoStar and others commenting in our Inquiry observe, multipath can
    pose difficulties for reception of digital television signals and,
    at the beginning of the DTV transition, receiver adaptive equalizers
    were not able to adequately process many real world multipath
    conditions. From the record of our Inquiry and our on-going
    monitoring of DTV receiver performance, including the testing
    performed in the FCC study, it is apparent that the current
    generation of digital TV receivers is able to provide service under
    most multipath conditions that they may encounter. This can be seen
    from an earlier field study by the Commission in 2001 that examined
    DTV reception at a number of sites randomly selected throughout the
    Washington, DC area. That study, which was based on second and third
    generation receivers, observed successful reception of DTV service
    at 99% of the locations where the field strength was at or above the
    level expected to be needed for service using a mast-mounted antenna
    at 30 feet. Similarly, that study found successful reception at 85%
    of the tested locations when using an indoor antenna outdoors at
    7-feet. The reason for that level of successful reception with those
    older receivers is that the number of locations where multipath
    conditions are difficult is relatively low. The FCC Study indicates
    that these reception success rates were achieved using a receiver
    performing in the lower tier of Figure 2. Figure 2 demonstrates that
    the latest generation of equalizer technology - represented by the
    upper tier of Figure 2 - provides service when subjected to most of
    the difficult ATSC multipath ensembles, most of which were recorded
    with indoor antennas.

78. We also considered the information provided by EchoStar and H&E
    indicating that, in processing multipath signals, a DTV receiver's
    adaptive equalizer could generate additional noise that could
    effectively increase the receiver's noise figure, and thus reduce
    its sensitivity so that a higher level of input signal could be
    needed to provide service. It is true that the process of multipath
    cancellation can cause a "white noise enhancement" - a degradation
    in performance that causes a higher input S/N to be required in the
    presence of multipath than in its absence; however, difficult
    multipath conditions leading to degradations by as much as 2 dB, as
    argued by EchoStar and H&E, are not expected to be the norm. The
    *2001 Field Test Receiver Study* demonstrated that the then-latest
    generation receiver (with equalizer technology that is now obsolete
    by two generations) performed better in terms of required S/N in
    typical multipath conditions than older receivers---indicating a
    trend toward less degradation in performance in the presence of
    multipath with successive generations of hardware. That receiver
    exhibited a median required S/N of 15.9 to 16.0 dB across all of the
    \"coverage sites\" tested in those field tests using an outdoor-type
    antenna. This performance is only 0.7 to 0.8 dB worse than the
    15.2‑dB S/N in the planning factors.[^148] Though the FCC has not
    tested the newer generations of equalizers in this regard, there is
    information to suggest that the noise enhancement of the fifth
    generation is even lower than past generations.[^149] Furthermore,
    the FCC Study notes that, if noise enhancement raises the required
    S/N to 16.0 dB, when this change is combined with the median
    measured noise figures of the 28 tested receivers, the overall
    result is a more optimistic prediction than the value stated in OET
    Bulletin No. 69 by 0.4 dB and 1.6 dB, respectively, in the low-VHF
    and high-VHF bands and a less optimistic prediction than the current
    OET-69 by only 0.7 dB in the UHF band.[^150] Accordingly, we do not
    believe that a factor for multipath should be added to the minimum
    signal level assumed to be needed to receive DTV service.

3\. Other Planning Factors

79. *Thermal Noise and Man-made Noise*. The thermal noise planning
    factor of -106.2 dBm is based on a 6 MHz bandwidth channel and an
    assumed temperature of 290^o^ K. As pointed out by dLR and the
    Network Affiliates, thermal noise is a function of the laws of
    physics and has not and will not change.[^151] We therefore find
    that the planning factor value for thermal noise is appropriate and
    should not be changed.

80. In their comments and engineering statement, EchoStar and H&E argue
    that the digital TV field strength standards should be revised to
    account for man-made noise.[^152] They contend that man-made noise
    is typically impulse noise from sources such as power line arcing,
    industrial machinery, automotive ignition systems, appliances having
    electric motors (vacuums, dishwashers, hair dryers, etc.), devices
    with switching power supplies (computers), and microwave ovens. They
    submit that man-made noise was not adequately taken into account in
    the DTV planning factors, particularly at the low VHF channels.
    EchoStar and H&E state that, as a result, the Commission did not
    build in a sufficient margin for noise when it set the DTV signal
    strength standard for those channels. H&E submits that a 1974 study
    by NTIA found that in rural locations man-made noise levels are
    typically above 20 dB and in urban areas such noise is typically
    above 30 dB near 54 MHz (channel 2).[^153] It also states that a
    more recent 2001 NTIA study found that median noise levels in
    Boulder, Colorado approached 20 dB at 137 MHz, which it argues
    implies a median value approaching 30 dB at 54 MHz.[^154] H&E
    contends that if 20 dB or 30 dB of man-made noise is added to the
    thermal noise floor, some viewers in urban areas will be unable to
    receive low VHF signals due to excessive man-made noise. EchoStar
    and H&E therefore submit that the signal strength standard for low
    VHF channels should be increased by 12-30 dB to account for such
    noise.

81. In their reply comments, the Network Affiliates state that EchoStar
    and H&E have misrepresented the results of the NTIA reports.[^155]
    They submit that the 2001 NTIA study cited by EchoStar and H&E
    actually found man-made noise at 137 MHz (between the low VHF and
    high VHF bands) to be 17.5 dB in business areas and only 3.6 dB in
    residential areas.[^156] The Network Affiliates state that at UHF
    frequencies, this study found that it was not possible to
    differentiate man-made noise from system noise, which indicates that
    man-made noise is insignificant in the UHF band. They further submit
    that a 1998 NTIA study found that residential man-made noise had
    decreased, amounting to no more than 3 or 4 dB in residential
    areas.[^157] They submit that if the 10 dB receiver noise figure for
    VHF channels is comprised of 5 dB for receiver noise and 5 dB for
    environmental noise, then the 2001 NTIA study shows that man-made
    noise at VHF frequencies is within the planning margin (as it also
    is at UHF frequencies). The Network Affiliates therefore argue that
    EchoStar and H&E have provided no evidence to warrant adjustment of
    the digital TV signal strength standards, even at low VHF, for
    man-made noise. The NAB similarly submits that the 2001 NTIA study
    relied on by EchoStar in fact says exactly the opposite of what
    EchoStar claims, namely that man-made noise in residential areas is
    very low - only 3.6 dB.[^158] The NAB further states that if the
    Commission were to conclude that there is a concern about man-made
    noise at low VHF channels, the way to address it would be to alter
    the plans for the DTV transition, for example, by authorizing low
    VHF channel stations to operate at higher power.[^159]

82. We find that the record does not contain any current or substantial
    studies or other information that would indicate that man-made noise
    is present in the low VHF or other TV bands at levels that would
    warrant the addition of this element to the planning factors that
    underlie the DTV field strength standard. Given the information on
    residential man-made noise from both the 1974 and 2001 NTIA studies,
    it appears that the level of man-made noise typically occurring on
    the low-VHF channels in residential locations is only 3 or 4 dB, a
    level that is well within the tolerance of the low-VHF noise figure.
    We also note that TV viewers are likely to become aware of any
    effects on their TV reception by man-made noise arising from
    specific devices such as hair dryers, computers, microwave ovens and
    similar appliances through the simple act of turning those devices
    on and off. The solution in such cases is to make sure that those
    devices that might cause interference are turned-off when someone is
    watching television. Accordingly, we recommend that no revisions be
    made to the DTV planning factors and field strength standards for
    man-made noise.

83. *Transmission (Downlead) Line Loss*. The TV receive antenna and
    receiver are connected by a transmission line that carries the
    received signal to the receiver's input terminal. The received
    signal will experience some amount of attenuation as it travels over
    this line due to the line's inherent resistance and impedance
    characteristics. Today, most TV receiver systems use 75-ohm shielded
    cabling for this downlead connection. The 1 dB, 2 dB, and 4 dB
    downlead line loss figures for low VHF, high VHF, and UHF digital TV
    channels are based on the assumed use of 50 feet of 75-ohm shielded
    cable, *i.e.*, RG-6 coaxial cable.

84. In their comments responding to our *Inquiry*, dLR, Jules Cohen,
    MSW, the NAB and the Network Affiliates submit that the existing
    downlead loss planning factor values appear reasonable in light of
    published values for 75-ohm RG-6 cable.[^160] The Network Affiliates
    point out that the ITU has assumed a downlead line loss of 1.1 dB
    for low-VHF, 1.9 dB for high-VHF, and 3.3 dB for UHF, and that the
    ITU VHF line loss values are virtually the same as those assumed in
    the planning factor while the ITU UHF value is lower.[^161] In
    addition, dLR provides the following table of cable specifications
    for three different cable manufacturers, as shown in Table 7: [^162]

+-------------+-------------+-------------+-------------+-------------+
| **Spe       |             |             |             |             |
| cifications |             |             |             |             |
| from        |             |             |             |             |
| Ma          |             |             |             |             |
| nufacturers |             |             |             |             |
| of Coaxial  |             |             |             |             |
| Cable (75   |             |             |             |             |
| ohm)**      |             |             |             |             |
+-------------+-------------+-------------+-------------+-------------+
| Frequency   | M           | Cable Type  | Attenuation | Attenuation |
|             | anufacturer | and Model   |             |             |
|             |             |             | (dB/100 ft) | (db/50 ft)  |
+-------------+-------------+-------------+-------------+-------------+
| 69 MHz      | Belden      | RG 6/U      | 1.71        | 0.86        |
|             |             |             |             |             |
| (low VHF)   |             | Model 9116  |             |             |
+-------------+-------------+-------------+-------------+-------------+
|             | Channel     | RG6         | 1.79        | 0.90        |
|             | Master      |             |             |             |
|             |             | 9533-500    |             |             |
+-------------+-------------+-------------+-------------+-------------+
|             | Coleman     | RG 6/U      | 1.9         | 0.95        |
|             |             |             |             |             |
|             |             | Model       |             |             |
|             |             | 992127      |             |             |
+-------------+-------------+-------------+-------------+-------------+
| 194 MHz     | Belden      | RG 6/U      | 2.73        | 1.37        |
|             |             |             |             |             |
| (high VHF)  |             | Model 9116  |             |             |
+-------------+-------------+-------------+-------------+-------------+
|             | Channel     | RG6         | 2.89        | 1.45        |
|             | Master      |             |             |             |
|             |             | 9533-500    |             |             |
+-------------+-------------+-------------+-------------+-------------+
|             | Coleman     | RG 6/U      | 3.2         | 1.6         |
|             |             |             |             |             |
|             |             | Model       |             |             |
|             |             | 992127      |             |             |
+-------------+-------------+-------------+-------------+-------------+
| 615 MHz     | Belden      | RG 6/U      | 5.00        | 2.50        |
|             |             |             |             |             |
| (UHF)       |             | Model 9116  |             |             |
+-------------+-------------+-------------+-------------+-------------+
|             | Channel     | RG6         | 5.57        | 2.79        |
|             | Master      |             |             |             |
|             |             | 9533-500    |             |             |
+-------------+-------------+-------------+-------------+-------------+

*Table 7. Coaxial Cable Performance Specifications*

85. dLR points out that in all cases the attenuation values assumed in
    the downlead loss planning factor exceed those of available
    products. They therefore submit that the current DTV planning factor
    values use conservative estimates of transmission line loss. Based
    on similar information, the NAB states that it is reasonable to
    assume that consumer downlead losses will be no greater, and often
    less than, those specified in the DTV downlead-loss planning factor.
    MSW indicates that the most expensive RG 6 or RG 59 cable costs
    about \$25 for the typical 50 foot length assumed in the planning
    factor.

86. In reply comments, EchoStar and H&E argue that it is not realistic
    to assume that most consumers will use RG 6 cable and that a number
    of other sources of loss, including baluns (matching transformers),
    splitters, and impedance mismatch are not accounted for at
    all.[^163] They state that it is not necessarily realistic to assume
    that consumers will use RG-6 cable and that budget conscious
    consumers may favor a less expensive alternative that subjects TV
    signals to greater attenuation. H&E argues that loss from baluns
    used to connect 300 ohm antennas to 75 ohm cabling results in loss
    of 0.6 dB at low VHF, 1.5 dB at high VHF and 2.5 dB at UHF. It also
    argues that the use of splitters that divide signals for delivery to
    serve more than one outlet will cause losses. H&E further argues
    that downlead attenuation will increase with the age of the cable.
    MSW counters that any significant losses from impedance mismatching
    or baluns can be corrected by use of a mast-mounted low-noise
    pre-amplifier.[^164] They state that the low-noise pre-amplifier
    would isolate the antenna impedance from that of the downlead cable
    and the DTV tuner impedance and also provide an output impedance
    much closer to the 75 ohm cable impedance. In their reply comments,
    the Network Affiliates state that while it is true that the DTV
    planning factors do not account for impedance mismatch between the
    antenna and the receiver front end, EchoStar's claim that the
    Voltage Standing Wave Ratio (VSWR) on downleads exceeds 2:1 and
    therefore results in an impedance mismatch loss of 3 dB is not based
    on empirical studies of consumer equipment. The Network Affiliates
    submit that a study by Schnelle and Wetmore concluded that the
    results of tests conducted on professional grade antennas show that
    it is possible for antennas to have low return and mismatch
    loss.[^165] That report concludes that it is therefore reasonable to
    conclude that consumer-grade antennas with good impedance matching
    capabilities are feasible.

87. Based on the record summarized above, we conclude that the current
    DTV downlead loss planning factor values continue to provide a
    conservative estimate of the attenuation a received signal will
    experience between the antenna and receiver. While we recognize that
    there are additional sources of loss that could reduce the signal
    level that arrives at a viewer's receiver, those sources are not
    likely to be present in a typical installation and could be
    addressed by using better cable or a pre-amplifier at any individual
    locations where those sources might pose a problem for DTV
    reception. We note that options for achieving the level of
    performance specified in the downlead loss planning factor are
    readily available at reasonable cost. We also understand that in
    some cases, lower cost downlead cabling with greater attenuation may
    be used by consumers. In this regard, we observe that in many
    instances the available DTV signals will be at levels that such
    cabling will provide satisfactory service. But these considerations
    do not alter the fact that cabling that meets and indeed exceeds the
    performance levels assumed in the planning factors is readily
    available at reasonable prices. Further, if the performance of
    cabling decreases with age it can and should be replaced in the same
    manner as any other component whose performance deteriorates or
    fails over time. We find that any losses from use of baluns would
    generally be of levels low enough to be compensated for by the
    margin present in the conservative planning factor values for
    downlead loss and antenna gain. Similarly, impedance mismatch has
    not generally been a problem for television reception and, as
    indicated by MSW, there are solutions available if it were to be so
    in specific cases. We reject EchoStar and H&E's argument that
    splitter loss should be included in the planning factors. The issue
    of whether sufficient signal strength is present for over-the-air
    rooftop reception is independent of a household's choice to use
    splitters to distribute signals to multiple TV sets within the home.
    In any event, "no loss splitters," *i.e.*, distribution splitters,
    the use of which does not result in any splitter loss, are readily
    and inexpensively available. Accordingly, we conclude that the
    current downlead loss planning factor values remain appropriate and
    recommend that these values not be changed.

88. *Time and Location Variability*. The field strength of digital
    television signals, like that of other radiofrequency signals,
    varies by time and location. That is, DTV signal strength will vary
    over time at the same location and will also vary from location to
    location. These variations of field strength with time and location
    are incorporated into the DTV planning model through use of the
    F(50,90) field strength curves to define a DTV station's
    noise-limited contour. As indicated above, the F(50,90) level of
    service means that at the edge of a station's noise-limited contour,
    50% or more of the locations can be expected to receive a signal
    that exceeds the field strength standards at least 90% of the time.
    It is possible to adjust these percentages by incrementing the field
    strength values upwards or downwards to reflect a desired level of
    signal availability. In the planning factors, the values for
    adjustments to provide different levels of time and location
    availability were set to zero.[^166]

89. In their comments in the *Inquiry*, EchoStar and H&E argue that the
    time variability assumption that a signal is available at least 90%
    of the time means that households predicted to be served may not
    actually have digital TV service for up to five weeks of the
    year.[^167] They argue that an increase in temporal reliability to
    99% or better would be prudent until there is greater experience
    with consumer reception of DTV signals. H&E submits that it
    collected temporal data on the amplitudes of fourteen DTV signals
    that could be received at its Sonoma, California offices. It states
    that it found that variation in signal strength around the median
    for six of the stations to be about 3.5 dB and 4.9 dB for 90%
    probability at high VHF and UHF, respectively. It argues that these
    values must be added to the DTV signal strength standard to achieve
    90% and 99% reliability of signal availability respectively. H&E
    states that its data also show that 4.7 dB and 17.5 dB would need to
    be added to the high VHF and UHF signal strength standards to
    increase to the 99% probability level.

90. In their reply comments, MSW, the NAB and the Network Affiliates
    contend that EchoStar and H&E's claim that 90% reliability means
    that a viewer will not receive a DTV picture for five weeks a year
    does not make sense.[^168] The Network Affiliates state that the
    statistical nature of the probability function means that any dips
    below the digital signal strength threshold will be randomly spaced
    over very long time periods and thus have no meaning in the sense of
    a consecutive time period. MSW, the NAB, and the Network Affiliates
    argue that it would be unfair to broadcasters to change the
    statistical definition of DTV service at this stage of the
    transition and that a change to 99% probability would greatly shrink
    local service areas. The Network Affiliates also argue that H&E's
    data collection is flawed in that H&E does not explain its
    methodology or its reasons for reporting data for only six of the
    fourteen stations it studied. In its reply statement, MSW submits
    that the results of the daytime field strength measurements taken by
    H&E ignore the fact that signal strength measurements taken during
    the daytime will be lower than at night when the majority of
    television viewing occurs.[^169] It notes that the original TASO
    studies in the late 1950's, as reported in FCC Report No. R-6602 and
    which provided the basis for the current FCC statistical propagation
    curves in Section 73.699 of the rules, were meticulously determined
    from testing and evaluation over a three year period.[^170] MSW
    states that most of the TASO data was collected over a period of at
    least six months and sometimes longer than two years, and from a
    multitude of locations. It therefore argues that a measurement
    program such as that conducted by H&E, consisting of only six paths
    taken over a two-week period, is not statistically valid and has
    little probative value, particularly when additional data was
    collected but not reported. MSW further submits that, according to
    FCC Report No. R-6602, signal strength for UHF signals are roughly
    2-3 dB lower during the daytime, depending on path distance. As a
    result, MSW reasons that signal strength measurements during the
    daytime are likely to be below the median over time.

91. We do not find persuasive reasons in EchoStar's and H&E's
    submissions for changing the DTV time variability planning factor
    value. The time variability value is an important factor in
    determining the area served by a television station and the amount
    of power needed to cover a planned service area. We believe that
    this value should not be changed in the absence of a strong
    indication that its use would be inconsistent with our DTV service
    model and channel allotment plan. In this regard, we note that
    radiofrequency signal propagation is always statistical in nature
    and that the power and/or antenna height needed to approach 100%
    reliability increases in a non-linear manner. As indicated by MSW,
    the NAB, and the Network Affiliates, changing the time variability
    factor values to 99% reliability at this stage of the transition
    would greatly shrink local DTV service areas. The current values
    were established based on an industry-Government consensus that
    relied on the traditional TV service model that worked well for
    analog TV service (the analog field strength values are based on the
    F(50, 50) service level with an augmentation to provide F(50, 90)
    reliability). We also observe, as pointed out by MSW in their reply
    filing, that the assumed 10% reduction in service availability
    occurs at the outermost limit of a station's service area; it is not
    the typical figure for time reliability across a station's entire
    service area. As the distance to a station's transmitter decreases,
    the time availability figure increases. Households at the edge of a
    station's service area can also improve their reception (and thereby
    reduce or eliminate periods when the station's signal is not
    available) by mounting their antenna higher, using a higher gain
    antennas, or using low-noise pre-amplifiers at their antenna.

92. We find that EchoStar's and H&E's argument that the F(50,90) values
    result in a loss of DTV service reception for more than five weeks a
    year ignores the fact that any actual interruptions of service tend
    to occur for short periods in a non-consecutive manner. There also
    appear to be serious methodological shortcomings in the data
    collection exercise conducted by H&E, in that it only examined
    daytime conditions for a short period and for a single location.
    Moreover, we see no theoretical justification for increasing the
    signal strength standard by adding a reliability factor amount equal
    to the variation in DTV signal strength measured over time.
    Considering all of the information on this issue, we are not
    persuaded that changes to the time variability planning factor
    values are warranted. In addition, no commenting party suggested
    changing the location variability factor and we know of no
    considerations that would lead us to recommend changing the current
    zero values for this factor.

93. *Dipole Factor*. The dipole factor expresses the quantitative
    relationship between the radiofrequency power received by a
    half-wave dipole antenna and the electrical energy that is present
    at the terminals of that antenna. This relationship is a function of
    the laws of physics. Essentially the dipole factor provides for the
    conversion of radiofrequency power to electrical power. In the DTV
    planning factors, the dipole factor is expressed in logarithmic form
    as the relationship between radiofrequency electric field strength
    and voltage, assuming a 75-ohm load. As indicated above, the DTV
    dipole factor values are -118.8 dBm, -120.8 dBm, and -130.8 dBm for
    low VHF, high VHF, and UHF, respectively.

94. In their comments in the *Inquiry*, the Network Affiliates observe
    that the dipole factor is dependent on frequency and that the
    planning factors use a geometric mean frequency of a UHF band
    extending from 470 MHz to 806 MHz (channels 14-69).[^171] They argue
    that because the core DTV channels extend only to channel 51, rather
    than 69, the dipole factor for the UHF band should be recalculated
    on the basis of the geometric mean frequency of the UHF band
    extending from 470 MHz to 698 MHz (channels 14-51). The Network
    Affiliates state that the geometric mean frequency of the core DTV
    UHF band is 573 MHz, which results in a dipole factor of -130.2 dB,
    or 0.6 dB lower than the current UHF dipole planning factor value.
    The effect of such a change would be to reduce the field signal
    strength level needed to receive UHF DTV signals by 0.6 dB, to 83.4
    dBm.

95. While the geometric frequency of the UHF band will indeed change
    from 615 MHz to 573 MHz at the end of the transition when all UHF
    DTV stations will operate in the channels 14-51 core spectrum, as
    indicated by the Network Affiliates, we do not believe that a change
    in the UHF dipole planning factor value is warranted. Initially, we
    note that the planning factors specify a single dipole factor value
    for the UHF band and additional single values for the low VHF and
    high VHF bands. Reducing the UHF dipole planning factor value would
    have the effect of reducing the minimum signal strength accepted as
    needed to receive service and thereby increase the geographic areas
    served by stations. The true dipole values are specific to each
    individual channel, as the conversion factor from electromagnetic
    energy to electric energy through an antenna varies with frequency.
    Thus, the planning factor dipole values for each channel range are
    only approximations of the actual dipole values for each channel. We
    note that unlike the planning factors, the Longley-Rice Model in OET
    Bulletin No. 69 includes a dipole modification factor that is added
    to the planning factor value so that DTV service area computations
    within a station's noise-limited contour are made using the true
    dipole factor.[^172] Thus, modification of the dipole factor to
    reflect the geometric mean frequency of the core spectrum would not
    have any effect on the actual service areas of individual DTV
    stations, because nothing in the physical operation of the stations
    would be changed. Given that the difference in the current UHF
    dipole factor and the dipole factor for the core spectrum UHF
    channels is only .6 dB and the fact that changing this planning
    factor would not actually affect the minimum threshold level of
    signal needed to receive individual stations, we find that this
    planning factor should not be changed. We conclude that the
    interests of maintaining stability in the service areas of TV
    stations outweigh the benefits of providing a small apparent
    reduction in the level of signal needed to receive UHF DTV
    stations.[^173]

4\. Additional Considerations

96. In response to Section 339(c)(1)(B)(vi) we also considered whether
    to account for factors such as building loss, external interference
    sources, or undesired signals from both digital television and
    analog television stations using either the same or adjacent
    channels in nearby markets, foliage, and man-made clutter in the
    digital television field strength standards. Our assessment of
    building loss in the case of indoor antennas as a potential factor
    in the digital television field strength standards are set forth in
    the discussion above concerning antenna gain, orientation, and
    placement. There, we observe that building losses are dependent on
    the materials with which the building is constructed and the
    location of an antenna within the building. Because of these
    variabilities, we conclude that it would be impractical to establish
    an indoor digital television field strength standard. We also
    observe that while the location of buildings with respect to outdoor
    antennas may have an effect on the signal strength that reaches an
    outdoor antenna, in most cases there will be many paths by which a
    digital television signal can generally be expected to reach that
    antenna despite the presence of buildings, other man-made clutter,
    and vegetation in the signal path. We therefore conclude that
    building loss should not be considered in the digital television
    field strength standard. On the other hand, blockage from buildings,
    other man-made clutter and vegetation is likely to be a factor in
    the digital television signal strength that is available at
    individual locations. These elements were previously factored into
    the predictive model used for determining analog television field
    strengths at individual locations, and we find that it would be
    appropriate to include those same factors into a predictive model
    for determining digital television field strengths at individual
    locations. That issue is discussed in the section below on the
    digital television predictive model.

97. Looking at the performance of DTV receivers in the presence of
    interfering signals, we observe that in general a radio receiver's
    immunity to interference is dependent on a number of factors in its
    technical design and, in addition, on the characteristics of the
    signals it is designed to receive. These factors may be closely
    related and possibly interdependent, and a receiver's performance on
    one factor may often affect its performance on others. The factors
    determining receiver immunity performance generally include
    selectivity, sensitivity, dynamic range, automatic RF gain control,
    shielding, modulation method, and signal processing. Receiver
    selectivity is the ability to isolate and acquire the desired signal
    from among all of the undesired signals that may be present on other
    channels. Sensitivity is the measure of a receiver's ability to
    receive signals of low strength. Greater sensitivity means a
    receiver can pick up weaker signals.[^174] Dynamic range is the
    range of the highest and lowest received signal strength levels over
    which the receiver can satisfactorily operate. The upper side of a
    receiver's dynamic range determines how strong a received signal can
    be before failure due to overloading occurs. Automatic RF gain
    control allows a receiver to adjust the level of a received signal
    as it appears at the unit's signal processing and demodulation
    sections.

98. In the *Inquiry*, we noted that many factors can affect the
    reception of radio frequency signals and the ability of a receiver
    to resolve these signals and produce a picture.[^175] Most notably,
    interference from both co-channel and adjacent channel TV
    transmitters could cause interference to the desired signal.
    Selectivity is a central factor in the control of adjacent channel
    interference.[^176] However, we also noted that different receiver
    designs may account for the differing abilities of receivers to
    reject greater or lesser amounts of interference. We requested
    comment on the interference rejection capabilities of digital TV
    receivers and satellite set-top-boxes with built-in off-air
    receivers.

99. In their comments responding to our *Inquiry*, ATI notes that in
    2003 the Commission suggested that the ATSC develop voluntary
    standards for DTV receiver performance[^177] and that in response
    the ATSC developed such standards and published them in its "A/74
    Recommended Practice: Receiver Performance Guidelines" (A/74
    Recommended Practice).[^178] The ATSC recommended DTV receiver
    performance standards were developed by industry parties
    representing broadcasters, consumer electronics manufacturers,
    consumers, and others. These standards address DTV receiver
    performance in the areas of sensitivity, multisignal overload, phase
    noise, selectivity, multipath, antenna interface and consumer
    interface. ATI recommends that the Commission adopt the ATSC A/74
    Recommended Practice for receiver performance because it reflects
    this cross-industry agreement and provides the most appropriate and
    accepted parameters for evaluating receiver performance.

100. H&E submits that two respected engineers have expressed concern
     about interference from adjacent channel intermodulation
     interference sources.[^179] It further states that it is aware of
     several failures of DTV reception that are attributable to "image
     interference" from strong undesired signals and notes that image
     interference (typically resulting from signals seven or eight
     channels above or below the desired channel) is not currently
     addressed by the Commission's DTV allotment standards. H&E states
     that while there currently is not enough information to assess
     typical receiver performance with regard to image interference, the
     existing protection ratios as documented in OET Bulletin No. 69
     might be presumptively used to determine the presence of
     interference and provide reasonable goals for DTV receiver designs.

101. We observe that a receiver's ability to provide service in the
     presence of interfering signals is not relevant to the field
     strength needed to provide service. While the presence of other
     signals on the same or adjacent channels does have the potential
     for causing interference that can cause loss of service, the
     effects of other signals are a separate matter from the basic
     functioning of a receiver in an interference-free environment that
     forms the basis for the Commission's field strength standards. In
     general, interference caused by the presence of a signal in the
     same channel as the desired channel (co-channel interference) is a
     problem that cannot be addressed by receiver improvements and must
     be addressed by avoidance of signal overlap. Interference from
     signals one or more channels removed from the desired channel
     (adjacent channel interference), however, can be addressed by
     designing receivers to be more selective and using antennas that
     provide discrimination against unwanted signals through
     directivity.

102. As a general matter, the Commission has traditionally refrained
     from attempting to regulate the ability of receivers to provide
     service in the presence of adjacent channels. Instead, it has
     relied on market forces to direct manufacturers to produce
     television sets that provide satisfactory service in the RF
     environment allowed by the Commission's rules. In this regard, the
     rules provide engineering and inter-station spacing standards that
     limit the signal strength of co-channel and adjacent channel
     signals that are present in a licensed station's service area.
     Manufacturers are then free to build receivers to whatever levels
     of performance they choose with respect to selectivity and other
     performance characteristics. Market forces provide incentives for
     manufacturers to design products that will operate within the RF
     environment that may exist in an area. If a receiver does not
     provide service in that environment, a consumer would very likely
     return it to the place of purchase thereby providing economic
     feedback to the manufacturer.

103. Over the years, this approach has worked very well and the
     Commission has not found it necessary to establish performance
     standards for TV receivers to avoid interference. For example, most
     recently in the 1999-2000 time frame it became apparent that the
     performance of the active equalizer function of digital television
     receivers that provides immunity to multipath was not adequate in
     the early models of receivers.[^180] Manufacturers responded to
     this performance problem by improving the performance of the
     adaptive equalizer function. That improvement effort, which is
     still on-going, has now produced the fifth generation DTV receivers
     that are able to provide satisfactory performance under most
     conditions of multipath. We continue to believe that reliance on
     market forces is the most appropriate approach for ensuring that
     DTV receivers perform satisfactorily with regard to their ability
     to handle interfering signals. That approach allows manufacturers
     the freedom to design products that meet a variety of consumer
     needs and also to implement changes that may be needed to implement
     new components, address a new understanding of the television
     signal environment, or meet changes in the consumer market. While
     we understand that a few parties may be concerned about the
     interference immunity performance of DTV receivers, the DTV
     receiver products currently on the market generally appear to be
     performing satisfactorily in rejecting interference. In this
     regard, we have not seen any obvious problems with the receivers on
     the market now failing to provide service because of interference.
     Thus, it appears that market forces are adequately providing for
     interference immunity.

104. We do believe that the ATSC A/74 Recommended Practice provides a
     strong benchmark for the performance capabilities. The standards in
     this document provide clear performance targets for the development
     of DTV receivers that provide quality performance within an
     economically feasible cost structure. While we strongly encourage
     manufacturers to consider and adhere to the performance standards
     in A/74 Recommended Practice, we do not find any compelling reason
     to make compliance with those or any other DTV receiver performance
     standards mandatory to ensure that television service is not
     affected by interference at this time. Accordingly, we do not
     recommend that Congress take any action with regard to the digital
     television field strength standards or otherwise adjust the methods
     for determining whether it is possible to receive television
     signals at a location to account for receiver interference
     performance.

C. Alternative Standards to Field Strength

105. In Section 339(c)(1)(B)(iii), Congress requested that the
     Commission consider whether a standard should be used other than
     the presence of a signal of a certain strength to ensure that a
     household can receive a high-quality picture using antennas of
     reasonable cost and ease of installation. In response to the
     *Inquiry*, CEA states that it believes that the presence of a
     signal of a certain strength is the right level of involvement of
     the FCC in determining the availability of TV service.[^181] It
     states that going beyond that approach would invite a quagmire of
     assessing reasonableness, cost effectiveness, and ease of
     installation. The NAB similarly submits that field strength
     standards are better than alternative approaches such as those that
     would use a "picture quality" test because qualitative tests
     involve subjective judgments. It argues that because the results of
     field testing by experienced engineers show that objective signal
     strength is an excellent proxy for the availability of a
     high-quality digital picture, there is no need for such judgments
     to be made. Based on our long experience with radio services, we do
     not believe that any alternative to field strength standards would
     provide a better indicator of whether a household can receive
     service. In this regard, we note that the DTV field strength
     standards in fact incorporate a large number of considerations, as
     evidenced by the technical criteria represented in the planning
     factors. We believe that the numerous elements that affect
     reception of digital television service are adequately and
     appropriately included in the standard through the DTV planning
     factors. Accordingly, we recommend that the current plan of field
     strength values and their specification remain the standards for
     determining whether digital television signals can be received. We
     further recommend that the Congress continue to allow the
     Commission to modify or replace those standards through the rule
     making process as may be necessary. We believe the flexibility of
     that process provides an adequate means for both identifying when
     and if changes are necessary and for developing appropriate
     revisions.

D. Summary Field Strength Standards Recommendations

106. From the above discussion, we observe that households face a wide
     range of situations in receiving over-the-air digital television
     service, just as they always have with analog television service.
     In the variability of receive sites there are some cases, *i.e.*,
     where a station's signal is particularly weak, in which a household
     that is within a TV station's service area may not be able to
     receive service using the typical TV reception system. In those
     cases there are readily available options to improve the capability
     of the households' receive systems to obtain over-the-air service.
     In other cases, *i.e.*, where a station's signal is particularly
     strong, a household may not need a receive system with the full
     capabilities of the typical receive system and, for example, may be
     able to use an indoor antenna. Given the ready availability of
     equipment for receiving service in locations with different levels
     of available field strength and the administrative efficiency of
     providing a simple, easy to understand and apply definition of DTV
     service area and signal availability, we continue to believe that
     it is appropriate to define digital television signal
     availability/service area using field strength standards that are
     specified on the basis of a typical receive system. For the reasons
     indicated in this discussion above, we believe any other approach
     that would introduce more variables and complexity could lead to
     subjectivity and arbitrariness in making determinations of signal
     availability. We also conclude that there is no alternative
     approach to field strength standards that would provide a more
     accurate measure of service area and/or signal availability at
     individual locations.

107. The variability that exists in receive conditions extends to the
     performance of the specific elements of the receive systems used by
     consumers. For example, a given household may not need to use a
     downlead that approaches 50 feet or the antenna it uses may provide
     less gain than that specified in the planning factors. In the
     evaluations above, we balanced the variability of these situations.
     The planning factor values were established as typical values that
     could be expected in a household's TV reception system. We also
     believe that the planning factor values as specified are in some
     instances, such as antenna gain, downlead loss, and receiver noise
     figure somewhat conservative. These values appear to provide a few
     dB of additional margin in the summation of factors that determine
     the minimum signal level needed for service so that the level of
     signal that is needed for service would be a little lower. On the
     other hand, certain other factors such as downlead impedance
     mismatch, balun loss, and in some cases additional noise from
     adaptive equalizer operation may tend to increase the minimum
     signal level needed for service by a few dB. We believe that these
     plus and minus elements generally negate one another and should
     have no impact on the basic calculation of the minimum signal level
     needed for service.

108. We therefore make the following recommendations with respect to the
     digital television field strength standards for use in determining
     households' eligibility to receive distant network television
     signals that are retransmitted by satellite:

-   Maintain the approach that specifies DTV service areas on the basis
    of field strength standards for the low-VHF, high-VHF, and UHF
    bands;

-   Maintain the existing planning factors in determining the DTV field
    strength standard,

-   Do not augment the field strength standards to account for indoor
    antennas, antenna rotational capability, receiver price, external
    interference sources including undesired from both digital and
    analog television stations, building loss, foliage, man-made
    clutter;

-   Maintain the existing DTV field strength standards for use in
    determining the availability of DTV service at the locations of
    individual households.

## IV. DIGITAL TELEVISION FIELD STRENGTH MEASUREMENT PROCEDURES {#iv.-digital-television-field-strength-measurement-procedures .unnumbered}

109. The Commission has standardized procedures for measuring the field
     strength of analog television signals at individual
     locations.[^182] Now, as we are on the horizon of transitioning to
     digital television, Congress has asked us to consider whether, for
     evaluating if a household is unserved for purposes of determining
     eligibility to receive distant network signals retransmitted from a
     satellite service, different field strength measurement procedures
     are necessary.[^183] Specifically, in Section 339(c)(1)(B)(ii) of
     the Communications Act, as amended by the SHVERA, Congress asked
     the Commission to consider whether S[ection 73.686(d)
     of](http://web2.westlaw.com/find/default.wl?DB=1000547&DocName=47CFRS73.686&FindType=L&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08)
     the Commission's rules should be amended to create different
     procedures for determining if the requisite digital signal strength
     is present than for determining if the requisite analog signal
     strength is present.

110. Currently, Section 73.686(d)(1)(i) requires that field strength
     measurements be made using either a half--wave dipole antenna that
     is tuned to the station's visual carrier frequency or a gain
     antenna, provided that the antenna factor for the channel under
     test is known.[^184] In addition, the rules specify that the
     intermediate frequency (i.f.) bandwidth of the measuring
     instrumentation be at least 200 kilohertz but no more than 1,000
     kilohertz.[^185] Measurements are to be taken in five locations,
     preferably close to the actual antenna or where one is likely to be
     mounted.[^186] In addition, the rules specify that the measurement
     antenna is to be raised to a height of 6.1 meters (20 feet) above
     ground for one story structures and 9.1 meters (30 feet) above
     ground for two story or taller structures.[^187] Finally, because
     the current rule was written specifically to determine the field
     strength of analog TV signals, the procedures specify that the
     field strength measurement is to be made on the visual
     carrier.[^188] The measured values are then to be compared to the
     field strength that defines the Grade B contour for the station in
     question to determine if the measured location is receiving a
     signal of sufficient intensity for analog television reception.

111. In the *Inquiry*, the Commission recognized that the rules defining
     measurement procedures for analog television cannot simply be
     applied to digital television signals.[^189] Thus, some
     modifications are necessary. As described above, the current
     measurement procedure requires that measurements be conducted on
     the visual carrier. Digital television signals, however, do not
     contain a visual carrier. Instead, all information -- video and
     audio -- is encoded within the bit stream that makes up the entire
     signal. We stated, therefore, that a new rule would be needed to
     deal with the measurement of digital television signals, at least
     insofar as it relates to the specific frequency on which to
     tune.[^190] The Commission pointed out that the digital television
     signal contains a pilot signal that is used by a receiver's tuner
     to lock onto the desired received signal and suggested that this
     signal could be used for measurement purposes.[^191] More
     generally, the Commission asked commenting parties to provide
     information on the signal characteristics to which the measurement
     instrumentation should be tuned (*e.g.*, pilot signal, center of
     channel, etc.). We also noted that the portion of the current rule
     for determining if a household is unserved by comparing the
     measured signal strength value to the Grade B contour field
     strength is not appropriate for digital television signals. For
     digital television stations, instead of a contour defined by Grade
     B signal intensity, the noise-limited service contour, as defined
     in Section 73.622(e) of the Commission's Rules, is used.[^192]

112. In addition to the Commission's request for comment regarding the
     aforementioned differences between analog and digital television
     signals, comment was also sought on other portions of the analog
     signal strength measurement rule and their applicability to digital
     television signals. We asked whether the i.f. bandwidth of the
     measurement equipment that is specified for analog television
     signals is also appropriate for digital TV signals. We further
     requested comment on the height that should be specified for the
     receiving antenna equipment to measure outdoor signals, and on
     whether specific procedures should be created for measuring the
     availability of indoor signals. Regarding indoor measurements, we
     asked if the Commission were to adopt such procedures, what
     criteria should be applied to determine whether an indoor or an
     outdoor measurement would be performed at a specific location.
     Finally, we asked if there are any other aspects of our measurement
     procedures that need to be modified for the purpose of determining
     if households are unserved by an adequate digital TV signal.

113. Congress, in SHVERA, also requested that the Commission consider
     whether to account for factors such as building loss, external
     interference sources, or undesired signals from both digital
     television and analog television stations using either the same or
     adjacent channels in nearby markets, foliage, and man-made clutter.
     In the *Inquiry*, we requested that commenting parties provide
     information regarding how to account for these factors.[^193] We
     noted that many factors can affect the reception of radio frequency
     signals such as interference from both co-channel and adjacent
     channel TV transmitters. We also noted that other external forces
     can affect the signal that ultimately reaches a TV receiver. These
     include natural and man-made structures that lie between the
     transmitter and the receiver. We observed that these obstructions
     can affect a signal in various ways such as by attenuating the
     signal so that the actual signal received is weaker than that
     predicted in the absence of any such obstructions or by creating
     multipath interference, which occurs when a signal bounces off
     structures and the main and reflected signals arrive at the
     receiver at different times.

114. *Inquiry Record*. NAB and the Network Affiliates state that
     existing methods for measuring field intensity at individual
     locations will, with a few minor modifications, work well for
     digital signals.[^194] Many of the suggested modifications are
     straightforward and are a direct result of the questions the
     Commission asked. For example, NAB points out that the rules for
     digital television measurements must reference the appropriate
     noise-limited field strength value rather than the Grade B
     contour.[^195]

115. In the *Inquiry*, the Commission observed that a change was
     necessary regarding how to actually measure the digital television
     signal strength given that the current rule is analog specific. The
     NAB and the Network Affiliates state that the Commission's
     suggestion to substitute a measurement of the pilot signal of a
     digital television signal for the analog measurement of the visual
     carrier would not be appropriate.[^196] They state that the problem
     with using the pilot signal is that in practice, multipath can
     create fluctuations of 10 dB which in turn would cause
     corresponding measurement errors.[^197] Instead, the NAB and the
     Network Affiliates specify that consistent with the Commission's
     definition of the power of a digital television signal,
     measurements should be conducted by tuning to the center of the
     digital television RF channel and measuring the integrated average
     power over the signal's 6 megahertz bandwidth. Several methods for
     performing this measurement are suggested: 1) using a swept-tuned
     spectrum analyzer with a variety of small i.f. bandwidths; 2) using
     a calibrated field strength meter that has one fixed narrow
     bandwidth, but can be swept across the entire 6 megahertz band;
     and 3) using a calibrated fixed tuned receiver that has an i.f.
     bandwidth equal to the 6 megahertz digital television
     channel.[^198]

116. The Network Affiliates and the NAB both suggest that the
     measurement system include a directional antenna rather than a
     simple dipole. Use of such an antenna, they assert, will help
     ameliorate the effects of multipath and also ensure that the
     measured power levels are sufficiently high to permit accurate
     measurement at all channel ranges.[^199] The NAB suggests use of a
     calibrated directional antenna with a front-to-back ratio
     protection consistent with Commission planning assumptions.

117. On another point, the Network affiliates and the NAB both suggest
     that the current procedure remain unchanged with respect to
     measurement height. They state that measurements should continue to
     be made outside at a height of 6.1 meters (20 feet) for a one-story
     home and 9.1 meters (30 feet) for a two-story home.[^200] While not
     disagreeing with the position of the Network Affiliates and the NAB
     on this point for outdoor measurements, EchoStar suggests that we
     establish indoor testing procedures. EchoStar states that because
     it is not practical for many households, such as those living in
     apartments, to use an outdoor antenna, procedures for testing with
     an indoor antenna are needed and that indoor testing should be
     required.[^201] To bolster this position, it references the
     statement from H&E which claims that due to limitations on physical
     size, indoor antennas have gain of about 9 dB below those for
     outdoor antennas. Therefore, EchoStar and H&E offer that indoor
     testing should be done using a typical indoor antenna or, if a
     professional antenna were used, then the signal test result should
     be reduced by 9 dB or more to account for the lower gain of the
     indoor antennas.[^202] The NAB and the Network Affiliates disagree.
     For example, the NAB states that the Commission should not permit
     testing of indoor antennas as it would be inconsistent with the
     premise of the DTV transition that households will make the same
     efforts to receive digital signals that they have historically made
     to receive analog signals.[^203] Further, they state that indoor
     testing would be impossible to standardize.[^204] The Network
     Affiliates add that local service would be eviscerated if the
     Commission was to recommend measuring signal strength indoors or
     establishing an indoor standard that the entire DTV service was
     never intended to meet.[^205] The NAB and the Network Affiliates
     state that this is because the signal attenuation due to building
     materials coupled with the lower gain antenna would have the effect
     of decreasing the service area size. Moreover, the Network
     Affiliates state that EchoStar's claims with respect to indoor
     antennas and building penetration are irrelevant given that the
     Commission has always assumed that homeowners would use an outdoor
     directional gain antenna for over-the-air reception. The NAB adds
     that EchoStar does not provide any explanation for the unfairness
     of assuming that the same household that uses an outdoor dish to
     receive satellite TV would use an indoor antenna for over-the-air
     signals.[^206]

118. A second area where EchoStar believes the current testing
     procedures should be modified is with regard to antenna pointing.
     The current procedure specifies that the measurement is to be taken
     with the antenna oriented in the direction of maximum signal
     strength. EchoStar claims that this requirement implicitly assumes
     that every household has a rotating antenna that can be re-pointed
     to optimize reception for each local station, which it contends is
     unrealistic.[^207] To this point, it suggests that signal strength
     loss from mispointing should be taken into account in the
     measurement procedures. EchoStar suggests further study to
     determine the "average" signal loss due to mispointing and submits
     that this value should be subtracted from the measured signal
     before comparing to the Commission's signal strength
     standard.[^208] It further suggests that because only 10-15% of
     households have rotors, those that do not may point the antenna in
     a direction other than the direction of maximum signal strength to
     achieve optimum reception for all stations. H&E argues that it
     would make sense to orient the measurement antenna in the same
     direction as other antennas in the area.[^209]

119. The NAB and the Network affiliates disagree with EchoStar on this
     point. NAB avers that EchoStar fails to explain why it would be
     good policy to assume an incorrectly pointed antenna when the
     entire DTV transition has been premised on use of a properly
     oriented antenna.[^210] The NAB and the Network Affiliates also
     state that EchoStar ignores obvious problems with their suggestion
     to point the measuring antenna in the direction of antennas at
     neighboring households. These include: 1) neighboring household's
     may have rotors and only temporarily point their antennas in a
     certain direction; 2) neighboring households may have antennas that
     have been abandoned; 3) there may be no neighboring households with
     outdoor antennas; and 4) there is no readily available methodology
     to determine the direction that neighboring households have
     oriented their antennas and translate that into a direction for
     orienting a test antenna.[^211] NAB further points out that in many
     areas local installers can supply antennas that are non-rotating,
     but that point correctly at all of the local stations when
     installed.[^212] They also state that in 83% of the television
     markets where there is a full complement of major network
     affiliates (ABC, NBC, CBS, Fox), the digital television stations
     are co-located.[^213]

120. Several other suggestions were made by EchoStar in response to our
     *Inquiry* questions concerning measurements. Specifically, it
     recommends that testing include collection of multipath and other
     interference data and that testing be done over time to account for
     time variability of the measurement. On the first point, EchoStar
     states that multipath interference is a more acute problem for
     digital television than for analog.[^214] It argues that dynamic
     multipath, which occurs due to signals bouncing off of moving
     objects, is difficult to account for, but that static multipath
     interference can be measured and its severity can be expressed as a
     signal strength penalty. EchoStar states that this penalty should
     be subtracted from the measured digital signal strength before it
     is compared against the Commission's digital strength
     standard.[^215] In addition, EchoStar submits that field
     measurements should include the collection of white noise
     enhancement values.[^216] The Network Affiliates and the NAB both
     argue that such measurements and compensation are unnecessary. They
     point out that in the past it may have been true that digital
     television receivers had difficulty with multipath, but that
     current 5^th^ generation receivers can easily handle multipath
     conditions that those earlier receivers could not resolve. The NAB
     also points out that 6^th^ generation receivers that will encompass
     further improvements will soon be available.[^217] The NAB further
     states that there is no need to account for white noise enhancement
     since it only adds about 0.2 dB of noise that is more than made up
     by factors that overestimate the available signal strength required
     and thereby make the planning factors conservative. It states that
     these include the fact that real antennas have gains that exceed
     the planning factors, available coaxial cables have losses less
     than those assumed, and low noise amplifiers are readily available.

121. With regard to digital television signal time variability, EchoStar
     comments that the H&E study shows significant variability over time
     and that because the Longley-Rice predictive propagation model is
     based on empirical data about time variability, it would be strange
     for actual testing to ignore it completely. It therefore asserts
     that the testing procedures be modified to account for variability
     in signal strength over time. EchoStar suggests that this could be
     done by taking the specified cluster measurements and assuming they
     provide a median signal level and then applying a correction factor
     to achieve 90% time reliability.[^218] The result of such a
     correction would be to increase the minimum signal strength that
     defines digital television service. The NAB, in response, points
     out that the minimum signal level that defines digital television
     service is specified in the statute and as such any change cannot
     be done by regulation.[^219] As with its response to EchoStar on
     multipath, the NAB again states that the Commission's planning
     factors are already conservative and there is no reason to account
     for time variability by increasing the minimum signal strength
     standard.[^220]

122. *Evaluation*. Many of the suggestions made by commenters were
     noncontroversial and went unchallenged in the record of the
     *Inquiry*. In this regard, we note that the NAB and the Network
     Affiliates pointed out that the measurement rules are analog
     specific with respect to the signal strength standard and need to
     be modified. We agree and as supported by the record of the
     *Inquiry*, believe that the digital television measurement rules
     should specify the noise-limited field strength values as the
     minimum signal level that constitutes service to a household. We
     also agree with the NAB and the Network Affiliates that use of the
     average power in the DTV channel, rather than the level of the
     pilot signal, would provide a better measure of DTV signal strength
     for the reasons they indicate. Therefore, we plan to initiate a
     rule making proceeding in the near future to revise the measurement
     procedure to use average power integrated over the entire 6
     megahertz bandwidth as the basis for measuring the digital
     television signal.[^221] As for the question in the *Inquiry*
     regarding whether the i.f. of the measuring equipment needs to be
     specified, we believe that it is not necessary to specify an i.f.
     other than that it cannot be greater than 6 megahertz. Any of the
     methods suggested above will work and the i.f. is essentially
     irrelevant so long as it is not larger than 6 megahertz and the
     equipment is capable of integrating the power over the selected
     i.f. bandwidth.

123. We make no make no specific recommendation on whether the
     measurement procedure should include provisions requiring the use
     of a directional antenna. However, we believe there may be merit to
     this suggestion by the NAB and the Network Affiliates. We believe
     that the proper place to address this is through a rule making
     proceeding conducted by the Commission. We point out, however, that
     should it be determined through rule making that a calibrated
     directional antenna is to be used, the requirements of the antenna
     (*e.g*., gain, half-power beamwidth, etc.) must be standardized so
     that the measurement test is not arbitrarily subject to the
     particular antenna selected by the tester.

124. Further, we agree with NAB and the Network Affiliates that digital
     television measurements should be made at 6.1 meters (20 feet) for
     one-story structures and 9.1 meters (30 feet) for two-story or
     taller structures; the same as analog television. This height
     standard is central to the definition of the planning model for DTV
     service areas. We therefore recommend that the procedures for
     measuring digital signals not be changed from the analog standard
     with respect to measurement height.

125. The SHVERA specifically asks the Commission to consider whether to
     account for the fact that some households use indoor antennas. As
     discussed above in the section on signal strength standards, the
     channel allotment plan for digital television developed by the
     Commission which defines the DTV service areas is premised on the
     planning factors; one of which is that an outdoor antenna is used.
     Households may certainly employ indoor antennas, but for
     standardized testing and planning an objective procedure must be
     used. To do otherwise would introduce a level of subjectiveness
     such that the entire testing process could be rendered meaningless.
     To begin with, there is the question of where within a household
     would the testing take place? If the antenna is in an attic, it may
     not be easily accessible for conducting the test at its location.
     Then, what if modifications are made to the house, such as new
     siding or a new roof. Would that subject the household to
     additional testing? And what if there are several televisions in
     the household using different antennas? In that situation, it is
     possible to conceive a scenario where one television could be
     eligible for receiving a distant signal and another could be
     ineligible. Further, there is the issue of what antenna to use for
     testing. EchoStar suggests using a typical antenna, but does not
     define a typical antenna. An essential part of the test system
     cannot be left to choice. A good test must be repeatable. There are
     too many elements of variation in an indoor measurement that would
     render such a test essentially meaningless.

126. In addition, the Commission is on record that it expects households
     to make similar efforts to receive digital television as they made
     for analog. There is good reason for this position. If it was
     expected that households could do less, then it could have the
     effect of drastically shrinking the service areas of television
     stations. Or, as discussed above, to keep the same service area,
     stations would need to significantly increase their power, which
     could lead to interference situations. Neither of these outcomes is
     desirable. Additionally, many stations already have fully
     operational digital television facilities that have been built
     based on the rules and policies in place. It is our opinion that
     forcing these stations to change now would have an unknown effect
     on the number of households considered unserved and could have the
     effect of stifling the transition to digital television. For the
     reasons articulated above, we recommend that the measurement
     procedures for determining whether a household is unserved not
     include provisions for indoor testing.

127. Concerning antenna pointing, we continue to believe that for
     testing purposes of determining if a household is unserved under
     SHVERA, the procedures should remain consistent with those in use
     today. As with the suggestion above regarding the use of indoor
     antennas, we believe that it would be arbitrary to allow for any
     practice other than pointing the antenna in the direction of
     maximum signal strength. To allow other antenna orientation would
     not satisfy good engineering practice as the outcome would be
     subject to the individual tester rather than being objective.
     Further, as discussed above, rotors are readily available at
     reasonable cost (approximately \$55-\$100).[^222] Thus, there is no
     undue burden on households to use a rotor. To move away from
     current practice, especially in a manner that is subjective, for
     the purpose of determining if a household is unserved under SHVERA
     would have the effect of treating similarly situated households
     differently depending on the particular person conducting the
     measurement. Thus, we recommend that the measurement procedure not
     be modified with respect to the requirement to orient the test
     antenna in the direction of maximum signal strength.

128. We do not recommend that the digital television measurement
     procedures for determining if a household is unserved under SHVERA
     include adjustments for multipath or time variability as suggested
     by EchoStar. As the NAB states, our planning factors are already
     conservative and overestimate available signal strength. Thus, any
     variation in the signal values due to multipath, white noise
     enhancement, or time variability are already more than compensated
     for. In addition, if a time variability factor is added, a long
     term study possibly over several years would need to be conducted
     for it to be properly characterized. By the time such a study could
     be completed, it is likely that the transition to digital
     television would be near completion. Furthermore, many digital
     television stations have been operational for some time now and
     there is no evidence that the current minimum signal strength
     values have been inadequate over time.

129. Finally, we note that commenters did not address co-channel or
     adjacent channel interference or clutter with respect to
     measurement. However, on this point, we note that the Commission's
     channel allotment procedures were designed to minimize the
     possibilities of this type of interference. In addition, television
     manufacturers are aware of the planning factors and the
     Commission's rules regarding interference levels and account for
     interference in their receiver designs by adjusting the receiver
     selectivity and adjacent channel rejection characteristics of the
     receiver. We also observe that, if interference is present whether
     from other television channels, clutter, etc., when conducting a
     measurement, then that interference is directly included in the
     measurement result. Thus, no special provisions are necessary in
     the measurement procedures.

130. *Summary of Field Strength Measurement Procedure Recommendations*.
     As stated above, the current measurement rules are specific to
     analog television and must be updated to properly provide for
     measurement of digital television signals. Based on the comments
     received as well as our own evaluation, we recommend that the
     procedures for measuring digital television signals generally be
     similar to the current analog procedures which have been in use for
     some time with good results. Certain modifications are needed,
     however, to address differences in the analog and digital
     television signals. These modifications include the measurement of
     average power in the 6 MHz channel rather than measurement of the
     analog video carrier and determination of whether a household is
     unserved based on comparison of measured field strengths to the DTV
     noise-limited field strength standards rather than the analog Grade
     B field strength standards. In addition, we recommend that the DTV
     measurement procedures allow the use of any i.f. bandwidth so long
     as it is not greater than 6 MHz bandwidth of the DTV channel.

131. Because the current test procedures are set forth in the
     Commission's rules, these changes can only be implemented via a
     rule making proceeding. Because measurements of station's digital
     signals may begin as early as April 2006, the Commission will
     explore, in the near future, the rule changes necessary to
     establish proper procedures for testing the strength of digital
     television signals in such a rule making proceeding. We provide a
     brief description of the measurement procedure that we believe
     should be used for the evaluation of digital television signals
     below:

-   Test antenna - The test antenna shall be either a standard half-wave
    dipole tuned to the center frequency of the channel being tested or
    a gain antenna, provided its antenna factor for the channel(s) under
    test has been determined. Use the antenna factor supplied by the
    antenna manufacturer as determined on an antenna range.

-   Testing locations - At the test site, choose a minimum of five
    locations as close as possible to the specific site where the
    site\'s receiving antenna is located. If there is no receiving
    antenna at the site, choose a minimum of five locations as close as
    possible to a reasonable and likely spot for the antenna. The
    locations shall be at least three meters apart, enough so that the
    testing is practical. If possible, the first testing point should be
    chosen as the center point of a square whose corners are the four
    other locations. Calculate the median of the five measurements (in
    units of dBu) and report it as the measurement result.

-   Multiple signals - If more than one signal is being measured
    (*i.e.*, signals from different transmitters), use the same
    locations to measure each signal.

-   Measurement procedure - Measurements shall be made in accordance
    with good engineering practice.

-   Testing equipment set-up -- Perform an on-site calibration of the
    test instrument in accordance with the manufacturer\'s
    specifications. Tune a calibrated instrument to the center of the
    channel being tested. Measure the integrated average power over the
    full 6 megahertz bandwidth of the television signal. The i.f. of the
    instrument must be less than 6 megahertz and the instrument must be
    capable of integrating over the selected i.f. Take all measurements
    with a horizontally polarized antenna. Use a shielded transmission
    line between the testing antenna and the field strength meter. Match
    the antenna impedance to the transmission line at all frequencies
    measured, and, if using an un-balanced line, employ a suitable
    balun. Take account of the transmission line loss for each frequency
    being measured.

-   Weather - Do not take measurements in inclement weather or when
    major weather fronts are moving through the measurement area.

-   Antenna elevation - When field strength is being measured for a
    one-story building, elevate the testing antenna to 6.1 meters (20
    feet) above the ground. In situations where the field strength is
    being measured for a building taller than one-story, elevate the
    testing antenna 9.1 meters (30 feet) above the ground.

-   Antenna orientation - Orient the testing antenna in the direction
    which maximizes the value of field strength for the signal being
    measured. If more than one station\'s signal is being measured,
    orient the testing antenna separately for each station.

-   Test Records - Written record shall be made and shall include at
    least the following: 1) a list of calibrated equipment used; 2)
    detailed description of the calibration of the measuring equipment,
    including field strength meters, measuring antenna, and connecting
    cable; 3) all factors which may affect the recorded field, such as
    topography, height and types of vegetation, buildings, obstacles,
    weather, and other local features for each spot at the measuring
    site; 4) a description of where the cluster measurements were
    made; 5) the time and date of the measurements and signature of the
    person making the measurements; and 6) a list of the measured value
    of field strength (in units of dBu and after adjustment for line
    loss and antenna factor) of the five readings made during the
    cluster measurement process, with the median value highlighted for
    each channel being measured.

## V. PREDICTIVE MODELING {#v.-predictive-modeling .unnumbered}

132. Currently, households have two methods of determining if they are
     unserved by a local analog television signal: predictive modeling
     and testing. Predictive modeling is a simple, cost-effective method
     for determining if a signal at a given location meets certain
     criteria for availability, such as its strength over a percentage
     of time. The Commission has established a predictive model that
     evaluates the coverage and interference of a particular digital TV
     station. This model, described in OET Bulletin 69, uses the
     Longley-Rice radio propagation model to make predictions of radio
     field strength at specific geographic points based on the elevation
     profile of terrain between the transmitter and each specific
     reception point.[^223] The Commission, in accordance with SHVIA,
     has also implemented the use of a modified Longley-Rice model known
     as the "Individual Location Longley-Rice" (ILLR) model, for
     identifying unserved households attempting to receive analog
     broadcast signals.[^224] We implemented an improved version of the
     ILLR model in order to make the predictive model more accurate by
     taking terrain features (such as hills), buildings, and land cover
     (such as forests) into account.[^225]

133. The ILLR model has proven over time to be an accurate and reliable
     predictor of signal strength and has been well accepted by both the
     broadcast and DBS industries. In the current satellite distant
     signal eligibility scheme for analog television signals, predictive
     modeling is used first to determine a household's status as served
     or unserved by a local television signal. Based on the model's
     results a household may request an actual field measurement if it
     believes the predictive modeling is not an accurate predictor of
     actual conditions. Under the SHVERA, Congress provided that
     eligibility determinations be made only on the basis of field
     testing and did not include any provisions for use of predictive
     modeling. Recognizing the benefits of predictive modeling, however,
     Congress, in Section 339(c)(1)(B)(iv) of the amended Communications
     Act, asked the Commission to consider whether to develop a
     predictive methodology for determining whether a household is
     unserved by an adequate digital signal under section 119(d)(10) of
     title 17, United States Code.[^226] On a related issue, in Section
     339(c)(1)(B)(vi) Congress also requested that the Commission
     consider whether to account for factors such as building loss,
     external interference sources, or undesired signals from both
     digital television and analog television stations using either the
     same or adjacent channels in nearby markets, foliage, and man-made
     clutter.[^227]

134. To examine these issues, the Commission, in the *Inquiry*,
     requested comment on whether the improved ILLR model, with
     appropriate modifications, would accurately predict digital signal
     coverage at a specific location, or whether there is some other
     predictive model that would be more appropriate for this purpose.
     The Commission asked that commenters who propose either specific
     modifications to the improved ILLR model or alternative models
     provide detailed analysis as to how their proposed modifications
     will improve the ILLR model's prediction characteristics and/or an
     explanation of how the changes or alternatives would more
     accurately model the available signal level when accounting for
     terrain and possible signal interference.

135. *Inquiry Record*: The parties commenting in our Inquiry were
     supportive of the Commission developing a predictive model. For
     example, DirecTV states that the most important lesson from the
     last decade of distant network signal qualification with regard to
     analog television is that predictive modeling is better than
     on-site testing. EchoStar submits that it appears that the
     predictive methodology currently used in the SHVA context, *i.e.*,
     the ILLR model, has considerable applicability to the DTV world,
     although there remain improvements that might be made to
     accommodate reliable DTV reception. In supporting the ILLR model,
     the Network Affiliates explain that on-site testing is not the norm
     today[^228] and that on-site testing frustrates and inconveniences
     subscribers, costs more money than it is worth, and should only be
     used as a last resort.[^229] DirecTV describes the current process
     as one in which subscribers must wait at least 30 days after
     receiving the results of predictive modeling while broadcasters
     decide whether to grant a waiver for them to receive distant
     network signals. It states that if such a waiver is denied, then
     the subscriber must wait until an independent, qualified tester can
     be identified in their area, wait for the tester to arrange an
     appointment and wait for the test to take place (and often tests
     are delayed due to weather or scheduling issues).[^230] It further
     states that because the actual test is of a signal level rather
     than someone looking at their television picture, customers get
     frustrated with the testing process.[^231] Finally, it provides
     that testing is a losing proposition as the average cost of a test
     is approximately \$150 (with some as high as \$450) and that it
     takes at least five years to recoup that cost from subscriber
     revenue.[^232]

136. Those that commented on this issue all endorse use of the improved
     ILLR model that the Commission has already been using. CEA states
     that the ILLR model is a very good tool with years of engineering
     development and that it is not aware of any industry discussion
     regarding a better model for this purpose.[^233] The Network
     Affiliates recommend use of the ILLR model. They state that analog
     TV coverage is predicated upon this model and the broadcast and
     satellite industries have five years of experience with its
     use.[^234] However, the NAB and the Network Affiliates submit that
     a DTV ILLR model should only be used after the transition to
     digital television is complete. They believe that otherwise the
     process would be too complicated and confusing.[^235] In this
     regard, the NAB explains that in the short term (prior to the end
     of the digital transition) problems could arise due to variations
     in dates that different stations will actually begin broadcasting
     digital signals.[^236] It states that few translator stations have
     channel assignments, much less fully functioning facilities and
     many full power stations won't be subject to testing until July
     2007 or later.[^237] The NAB further states that Congress postponed
     the date on which many broadcast stations would begin to be subject
     to testing because Congress recognized that it would be unfair to
     penalize a station for not delivering a digital signal when it
     cannot be reasonably expected to do so.[^238] It contends that
     Congress created a complex and somewhat unpredictable schedule for
     when stations would be subject to testing in order to protect
     stations from a draconian loss of viewers due to circumstances
     beyond their control. On this point, the NAB argues that since
     Congress barred site testing of certain station's digital signals,
     it would be equally improper to subject those stations to
     predictions of the signal strength of those same signals.[^239] The
     Network Affiliates offer similar comments.[^240] The NAB further
     comments that it believes that what Congress intended here is that
     if a station is not yet eligible to have its digital signal
     evaluated, then the analog signal should be evaluated instead.
     This, the NAB and the Network Affiliates aver, would be the logical
     way to give stations "credit" for coverage when they have been
     excluded from testing.[^241]

137. The NAB continues that the ILLR model should be used in the long
     term (after the digital transition) because it does exceptionally
     well at predicting whether or not particular locations will receive
     a signal above the DTV minimums. It states that the model provides
     correct predictions 95% of the time and that when errors do occur
     they are evenly divided between over and under predictions.[^242]
     MSW draws a similar conclusion for use of the ILLR model with
     respect to DTV. It studied real world empirical data from thousands
     of measurements in 12 different U.S. cities and submits that the
     data shows that the Longley-Rice model correctly predicted 94.4% of
     the time when the signal would be above the DTV minimum.[^243]

138. EchoStar submits that changes are needed in the ILLR predictive
     model to make it suitable for use in predicting the availability of
     DTV signals. It states that the model should be modified to include
     an improved time variability factor and to incorporate more
     realistic values for system noise, building penetration, and land
     cover and clutter.[^244] EchoStar submits that the analog ILLR
     model is based on a time variability factor of 50%, which means
     that the model assumes that a household is unable to receive an
     analog signal at or above the minimum level about half of the
     time.[^245] It infers that for digital television this similarly
     means that there will be an inability to receive a digital picture
     about half the time. EchoStar avers that even a time variability
     factor of 90% means a subscriber will not have reception for up to
     5 weeks a year. As a remedy, it suggests that the model be modified
     to incorporate an increase in temporal reliability to 99% or more
     until there is greater experience with digital television.[^246]
     H&E also argues that 90% time reliability seems not to be in the
     consumer's best interest.[^247] The NAB and the Network Affiliates
     counter EchoStar by stating that changing to a 99% time variability
     factor amounts to changing the rules in the middle of the
     game.[^248] MSW avers that EchoStar overestimates the impact of the
     time variability factor. It explains that any loss of service does
     not occur over the entire service area, but only at outer edges of
     a television station's service area and even there any outage that
     occur are not consecutive, nor is the time duration of a particular
     outage known. MSW states that many instances of service loss will
     occur during times when no one is watching TV or may be so short as
     to only cause a momentary disruption. MSW offers that for those
     households at the edge of the service area, reception can be
     improved with a mast-mounted low noise amplifier (LNA).[^249]

139. With respect to system noise, EchoStar states that the planning
     factors underlying the Commission's DTV field strength standards
     assume that the impedance is matched between the receiver and the
     antenna.[^250] It claims that this is rarely the case in practice
     and that the predictive model should take this into account and use
     a noise figure increased by 3 dB to correct for this inaccuracy in
     the planning factors.[^251] EchoStar obtains this 3 dB figure by
     observing that many DTV antennas have voltage standing wave
     ratio[^252] (VSWR) values that exceed 3:1 over much of their design
     bandwidth and that exceed 2:1 over essentially all of their design
     bandwidth.[^253] On this point, MSW argues that impedance mismatch
     loss between a TV antenna and receiver as well as a higher digital
     television receiver noise figure can be mitigated by a mast-mounted
     LNA. In cases where such losses might be a problem, MSW states that
     an LNA resolves the matter by isolating the antenna impedance from
     that of the downlead coaxial cable and the DTV tuner input
     impedance.[^254]

140. EchoStar also argues that the DTV predictive model should account
     for building penetration. It contends that the H&E study shows
     building loss at VHF can be as high as 30 dB for high clutter
     areas. It adds that further study may yield a more complete set of
     figures on building penetration loss for incorporation into the
     model, especially for apartment dwellers with indoor
     antennas.[^255] MSW argues that as far as the model is concerned
     building penetration is irrelevant given that TV service should be
     established on the basis of an outdoor model and that therefore
     indoor measurements should not be performed.[^256]

141. Finally, on the topic of land use and land clutter, EchoStar notes
     that the Commission has recognized that incorporation of such
     factors into the predictive model would increase the model's
     accuracy. However, it observes that the Commission has set almost
     all the clutter-loss values for VHF channels to zero. It argues
     that this is a problem for analog television, but an even larger
     problem for digital because if the signal level falls below the
     minimum needed, then the entire picture is lost.[^257] NAB notes
     that the ILLR model is partially based on actual field measurements
     and thus already takes clutter into account to a significant degree
     because clutter affects real world field measurements. It also
     states that the ILLR model is already in balance at low-VHF and so
     no additional factors to adjust for clutter loss are needed.[^258]

142. *Evaluation*. When it enacted the SHVIA, Congress explicitly
     provided for the Commission to prescribe a predictive model to
     evaluate if a household is unserved by an analog television signal.
     That model -- the modified individual location Longley-Rice
     propagation model - has served the industry well as it has proven
     to be highly accurate over time. Through the use of this model,
     both consumers and terrestrial and satellite television operators
     have saved considerable time, money, and frustration that would
     come with having to conduct an actual measurement test every time a
     satellite customer believes that he/she is unable to receive an
     adequate signal off-the-air from a local television network
     affiliated station. The same situation is likely to exist with
     regard to digital television signals. Therefore, we recommend that
     Congress provide for the Commission to explore a similar model for
     digital television through a rule making proceeding.

143. Those commenters that provided input on this issue were all in
     agreement that a predictive model should be available for
     determining if a household is unserved by a digital television
     signal and that the model be the ILLR. We agree with those
     comments. The Longley-Rice propagation model has been used for
     considerable time and it has proven to be highly accurate at
     predicting the field strengths of television stations at a
     location. This is illustrated by the data presented by the
     commenters showing an accuracy rate of almost 95%.[^259]
     Additionally, because the standard Longley-Rice point-to-point
     coverage model was used to develop the digital television allotment
     plan, the industry already has considerable practice using this
     model for digital television in addition to the experience gained
     for analog television over the last few years. And since there do
     not seem to be any candidate models that would offer superior
     performance to the improved ILLR propagation model, a change at
     this point in time would entail substantial development and testing
     which would likely not be completed until after the transition to
     digital television is complete and a time when the satellite
     television providers offer local-into-local signals for most, if
     not all, TV designated market areas (DMAs). It is anticipated that
     at that point the requirements of SHVERA with respect to distant
     signal retransmission will be moot in most cases.

144. We note that while endorsing use of the ILLR, NAB and the Network
     Affiliates advocate its use only after the digital transition is
     complete, arguing that its use prior to this time would be
     confusing and serve to penalize stations that transition to
     broadcasting digital signals later rather than earlier but still in
     accordance with the prescribed timetable.[^260] They argue that
     local stations that build out their digital facilities at a later
     time would lose their local viewers to a distant network signal
     even though they are fully compliant with the law and the
     Commission's rules. We agree with NAB and the Network Affiliates
     that the timing governing the use of a predictive model should be
     consistent with the SHVERA provisions that permit subscribers to
     receive distant digital signals under specified circumstances.
     These provisions take account of various factors that could
     legitimately prevent a station from serving its potential digital
     service area at this time.[^261] The provision of the statute cited
     by NAB and the Network Affiliates applies to subscribers who are
     eligible for testing (*i.e*., subscribers who live within the area
     predicted to be served by the analog predictive model of a local
     network station and are seeking a distant digital signal for a
     station affiliated with the same network as the local network
     station).[^262] This provision further provides that stations that
     may be subject to a digital signal test may request a waiver from
     the Commission to prohibit such testing if the station proves that
     it satisfies the statutory criteria related to unremediable
     limitations on the station's digital signal coverage.[^263] Thus,
     if Congress amends the statutory provisions to recognize a
     predictive model with respect to digital signals and provides
     discretion for the Commission to develop such a model, the
     appropriate timing for use of the model should also be considered
     by Congress in conjunction with such legislative changes. Congress
     could, for example, provide that use of the model would be subject
     to the same waiver provisions that apply to stations with respect
     to digital signal testing.[^264] We also note that Congress is
     currently considering legislation to mandate the date on which the
     transition to digital television would end, which, in turn, is
     likely to influence the timing for use of a predictive model.

145. There were several suggestions made by commenters for further
     changing the ILLR model. These include changing the time
     variability factor, and incorporating different values for system
     noise figure, building penetration, and land cover and clutter.
     First, EchoStar argues that the time variability factor for DTV
     should be increased from 50% to 99%. We first note that the
     noise-limited contour that defines the digital television service
     area is based on planning factors which specify use of the
     F(50, 90) curves, not the F(50, 50) curves as implied by EchoStar;
     that is the digital signal level is at or above the minimum level
     at 50% of the locations for 90% of the time, not 50% of the time as
     suggested by EchoStar.[^265] We also note that the 90% availability
     level defines the edge of a station's service area and that at
     locations inside this contour the availability percentage would be
     greater than 90%. Further, as stated by MSW, the time when a signal
     is below the specified minimum value is likely to occur in small
     increments, some of which are when viewers are not even watching
     television. Thus, only a small minority of the total number of
     viewers may experience outages as high as 10% of the time. We also
     observe that the 90% availability level has been used to define
     analog TV service and has historically served viewers well. For
     these reasons, we do not recommend any changes to the digital
     television time variability factor for the purposes of SHVERA.

146. EchoStar also argues that the input for the system noise figure to
     the predictive model should be increased by 3 dB to account for
     impedance mismatch between the antenna and the receiver. We agree
     with EchoStar that there may be some loss in the transmission line
     and associated balun due to impedance mismatch. However, we do not
     believe that this loss is significant or that the predictive model
     input needs to be modified to account for such loss. First, as NAB
     states and we discuss above, our planning factors are conservative
     in that the available coaxial cable generally have losses less than
     those assumed in the planning factors.[^266] Second, there are
     readily available devices that consumers can use, including LNAs,
     to reduce mismatch in the transmission line and thus reduce such
     loss. We also believe that the other planning factors such as
     antenna gain and receiver noise performance are generally
     conservative such that together there is sufficient margin to
     compensate for any signal losses that may result from impedance
     mismatching. We therefore see no reason that the system noise
     figure should be increased for the purpose of using a predictive
     model to determine if a household is unserved.

147. Another area where EchoStar seeks changes in the improved ILLR
     predictive model is signal loss from building penetration. We
     disagree that this model should be augmented to account for signal
     loss from building penetration. As discussed above in the section
     on signal measurement, the channel allotment plan for digital
     television is based on the assumption that an outdoor antenna is
     used and the expectation that households will make similar efforts
     to receive digital television as they made for analog. Thus, any
     predictive modeling must reflect these assumptions consistent with
     the digital television planning factors. Otherwise, inaccurate
     results will ensue which could have the effect of decreasing
     confidence in the model. In addition, there is no accepted value
     for modeling the loss for building penetration as this phenomenon
     varies depending on the building materials, configuration of the
     structure, and other related factors. For these reasons, and given
     our recommendation in the section on measurement procedure that all
     measurements continue to be conducted outside, there is no reason
     for a predictive model to assume any building penetration loss.
     Therefore, we do not recommend that the model input reflect any
     such losses.

148. The last area where commenters seek changes in the predictive model
     is with respect to land use and land clutter. Currently, the
     predictive model used for analog television accounts for additional
     signal loss due to land use and land clutter. In developing the
     land use and land clutter adjustment values, the Commission
     determined, after careful consideration of the available data, that
     the correct loss value for VHF channels is 0 dB in all cases and
     for UHF channels the loss values vary depending on the type of land
     cover over which the television signal propagates.[^267] EchoStar
     argues that in addition to the loss added for UHF channels, there
     should be some loss associated with VHF channels. NAB and the
     Network Affiliates argue otherwise and take the position that the
     improved ILLR model already takes clutter into account to a
     significant degree because the model is partially based on actual
     field measurements and clutter affects real world field
     measurements. Any predictive model that is prescribed should
     provide output that is as accurate as possible; anything less would
     diminish its value as a tool for determining whether a household is
     able to receive off-the-air digital television signals. For the
     analog model, we believe that we struck the correct balance for
     clutter loss. This has been borne out by the data on the record of
     its performance, which shows that using the values adopted by the
     Commission the ILLR model produces approximately an equal number of
     over predictions as under predictions.[^268] Thus, a range of
     values, including zero, that correspond to different land cover
     types are valid. For any digital model that may be developed, we
     believe that the values currently in use for the analog model will
     similarly yield accurate results. We believe that the proper arena
     for discussing correct clutter loss values is in a rule making
     proceeding. Therefore, we believe that a range of clutter loss
     values ranging from zero upwards may all be valid inputs for a
     version of the ILLR model that is used for predicting the
     availability of digital television signals and recommend that
     clutter loss values be determined and then incorporated into the
     digital model through a process similar to that used to determine
     the clutter loss values used in the analog TV ILLR model.

149. *Summary of Predictive Model Recommendations*. In summary then, we
     recommend that Congress amend the copyright and Communications Act
     to recognize digital signal strength predictions for the purpose of
     determining whether a subscriber is \"unserved.\" We also recommend
     that Congress provide the Commission with authority to develop a
     predictive model for the purpose of determining households that are
     unserved by local digital signals for purposes of determining
     eligibility to receive retransmitted distant network signals under
     the SHVERA. For such purpose, we recommend that the existing
     Individual Location Longley-Rice (ILLR) predictive model be used.
     This model has been used to develop the channel allotment plan and
     we do not believe that any additional changes to the model inputs
     are necessary for purposes of SHVERA.

## APPENDIX A {#appendix-a .unnumbered}

Section 339(c)(1) of the Communications Act of 1934, As Amended

Section 339(c)(1) of the Communications Act of 1934, as amended by the
SHVERA, provides as follows:

> \(1\) STUDY OF DIGITAL STRENGTH TESTING PRODEDURES-
>
> \(A\) STUDY REQUIRED- Not later than one year after the date of the
> enactment of the Satellite Home Viewer Extension and Reauthorization
> Act of 2004, the Federal Commissions Commission shall complete an
> inquiry regarding whether, for purposes of identifying if a household
> is unserved by an adequate digital signal under section 119(d)(10) of
> title 17, United States Code, the digital signal strength standard in
> section 73.622(e)(1) of title 47, Code of Federal Regulations, such
> statutes or regulations should be revised to take into account the
> types of antennas that are available to consumers.
>
> \(B\) STUDY CONSIDERATIONS- In conducting the study under this
> paragraph, the Commission shall consider whether\--
>
> \(i\) to account for the fact that an antenna can be mounted on a roof
> or placed in a home and can be fixed or capable of rotating;
>
> (ii) [section 73.686(d) of title 47, Code of Federal
> Regulations](http://web2.westlaw.com/find/default.wl?DB=1000547&DocName=47CFRS73.686&FindType=L&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08),
> should be amended to create different procedures for determining if
> the requisite digital signal strength is present than for determining
> if the requisite analog signal strength is present ;
>
> (iii) a standard should be used other than the presence of a signal of
> a certain strength to ensure that a household can receive a
> high-quality picture using antennas of reasonable cost and ease of
> installation;
>
> (iv) to develop a predictive methodology for determining whether a
> household is unserved by an adequate digital signal under section
> 119(d)(10) of Title 17, United States Code;
>
> (v) there is a wide variation in the ability of reasonably priced
> consumer digital television sets to receive over-the-air signals, such
> that at a given signal strength some may be able to display
> high-quality pictures while others cannot, whether such variation is
> related to the price of the television set, and whether such variation
> should be factored into setting a standard for determining whether a
> household is unserved by an adequate digital signal; and
>
> (vi) to account for factors such as building loss, external
> interference sources, or undesired signals from both digital
> television and analog television stations using either the same or
> adjacent channels in nearby markets, foliage, and man-made clutter.
>
> \(C\) REPORT- Not later than one year after the date of the enactment
> of the Satellite Home Viewer Extension and Reauthorization Act of
> 2004, the Federal Communications Commission shall submit to the
> Committee on Energy and Commerce of the House of Representatives and
> the Committee on Commerce, Science, and Transportation of the Senate a
> report containing---
>
> (*i*) the results of the study under this paragraph; and
>
> (*ii*) recommendations, if any, as to what changes should be made to
> Federal statutes or regulations.

## APPENDIX B {#appendix-b .unnumbered}

Parties Submitting Comments and Reply Comments

[Parties Submitting Comments]{.underline}

1\. ABC, CBS, NBC, Network Affiliates

2\. The Association for Maximum Service Television, Inc.

3\. ATI Technologies, Inc.

4\. Consumer Electronics Association (CEA)

5\. DIRECTV Inc.

6\. EchoStar Satellite L.L.C.

7\. National Association of Broadcasters (NAB)

8\. Paul Robinson

9\. Viamorph

[Parties Submitting Reply Comments]{.underline}

1\. ATI Technologies, Inc.,

2\. ABC, CBS, and NBC Television Affiliate Associations

3\. Cohen, Dippell and Everist, P.C.,

4\. EchoStar Satellite L.L.C.,

5\. National Association of Broadcasters

## APPENDIX C {#appendix-c .unnumbered}

**Tests of ATSC 8-VSB Reception Performance\
of Consumer Digital Television Receivers Available in 2005**

**November 2, 2005**

**Technical Research Branch**

**Laboratory Division**

**Office of Engineering and Technology**

**Federal Communications Commission**

**OET Report Prepared by:**

**FCC/OET TR 05-1017 Stephen R. Martin**

**FOREWORD**

The author gratefully acknowledges the advice and technical support
offered by the following individuals and organizations. Gary Sgrignoli
and Dennis Wallace of MSW provided technical guidance at the inception
of the project, and Gary Sgrignoli also provided guidance later and
reviewed an early draft of this report. Mark Hryszko, Mike Gittings,
Raul Casas of ATI Research, Inc. identified degraded performance of the
FCC's RF capture player (which was subsequently repaired and calibrated
before conducting the tests reported herein) and provided technical
advice; Mark Hryszko and Kevin Murr assisted in comparative testing at
ATI's laboratory using ATI's equipment as a double-check of the FCC
equipment and measurement procedures for the FCC Laboratory tests
reported herein. Wayne Bretl of Zenith Electronics Corp. and Rich Citta
of Micronas Semiconductors, Inc. provided technical advice regarding
testing with RF captures. Victor Tawil of the Association for Maximum
Service Television (MSTV) and Sean Wallace of Wavetech Services, LLC
provided RF captures and technical advice.

**TABLE OF CONTENTS**

[EXECUTIVE SUMMARY iv](#executive-summary)

[Samples iv](#samples)

[Test Results iv](#test-results)

[CHAPTER 1 INTRODUCTION 1-1](#introduction)

[Background 1-1](#background)

[Objectives 1-1](#objectives)

[Ability to Receive Signals 1-2](#ability-to-receive-signals)

[Standard for Determining Whether a Household is Unserved
1-4](#standard-for-determining-whether-a-household-is-unserved)

[Overview 1-4](#overview)

[CHAPTER 2 SCOPE AND APPROACH 2-1](#scope-and-approach)

[Scope of Testing 2-1](#scope-of-testing)

[Test Samples 2-1](#test-samples)

[Test Philosophy and Approach 2-3](#test-philosophy-and-approach)

[CHAPTER 3 WHITE-NOISE THRESHOLD MEASUREMENTS\
(REQUIRED CARRIER-TO-NOISE RATIO)
3-1](#white-noise-threshold-measurements-required-carrier-to-noise-ratio)

[Measurement Method 3-1](#measurement-method)

[Format of The Bar Graph Data 3-2](#format-of-the-bar-graph-data)

[Results 3-2](#results)

[CHAPTER 4 MINIMUM INPUT SIGNAL MEASUREMENTS
4-1](#minimum-input-signal-measurements)

[Measurement Method 4-1](#measurement-method-1)

[Results 4-2](#results-1)

[CHAPTER 5 INFERRED NOISE FIGURE 5-1](#inferred-noise-figure)

[Results 5-2](#results-2)

[CHAPTER 6 PERFORMANCE AGAINST MULTIPATH USING FIELD CAPTURES
6-1](#performance-against-multipath-using-field-captures)

[Measurement Method 6-1](#measurement-method-2)

[Results 6-2](#results-3)

[CHAPTER 7 INFERRED PERFORMANCE AGAINST REPRESENTATIVE MULTIPATH
CONDITIONS
7-1](#inferred-performance-against-representative-multipath-conditions)

[Multipath Capability Based on Year-2000 Field Tests
7-1](#multipath-capability-based-on-year-2000-field-tests)

[Impact of Representative Multipath on Required CNR
7-2](#impact-of-representative-multipath-on-required-cnr)

[CHAPTER 8 SUMMARY AND CONCLUSIONS 8-1](#summary-and-conclusions)

[Variation in Reception Performance
8-2](#variation-in-reception-performance)

[Price-Dependence of Reception Performance
8-3](#price-dependence-of-reception-performance)

[Reception Performance Relative to OET-69
8-3](#reception-performance-relative-to-oet-69)

[APPENDIX A: TEST CONFIGURATIONS, ISSUES, AND PROCEDURES
A-1](#test-configurations-issues-and-procedures)

[Test Configurations A-1](#test-configurations-1)

[Calibration and Signal Quality Tests on Test Setups
A-2](#calibration-and-signal-quality-tests-on-test-setups)

[Test Issues A-4](#test-issues)

[Procedures A-6](#procedures)

[Equipment A-12](#equipment)

[APPENDIX B: SUMMARY OF RF FIELD CAPTURES
B-1](#summary-of-rf-field-captures)

**ILLUSTRATIONS**

[Figure 3‑1. Measured White Noise Threshold of Receivers
3-6](#__RefHeading___Toc119201837)

[Figure 4‑1. Measured Minimum Signal Level at TOV on Three Channels
4-5](#__RefHeading___Toc119201838)

[Figure 4‑2. Measured Minimum Signal Level at TOV on Channel 3 (Low VHF)
4-5](#__RefHeading___Toc119201839)

[Figure 4‑3. Measured Minimum Signal Level at TOV on Channel 10 (High
VHF) 4-6](#__RefHeading___Toc119201840)

[Figure 4‑4. Measured Minimum Signal Level at TOV on Channel 30 (UHF)
4-6](#__RefHeading___Toc119201841)

[Figure 4‑5. Measured Minimum Signal Level at TOV Versus Channel for
Receiver G2 4-7](#__RefHeading___Toc119201842)

[Figure 4‑6. Measured Minimum Signal Level at TOV Versus Frequency for
Receiver G2 4-7](#__RefHeading___Toc119201843)

[Figure 5‑1. Relationship between Minimum Signal at TOV and Required CNR
5-5](#__RefHeading___Toc119201844)

[Figure 5‑2. Noise Figure on Three Channels
5-5](#__RefHeading___Toc119201845)

[Figure 5‑3. Noise Figure on Channel 3 (Low VHF)
5-6](#__RefHeading___Toc119201846)

[Figure 5‑4. Noise Figure on Channel 10 (High VHF)
5-6](#__RefHeading___Toc119201847)

[Figure 5‑5. Noise Figure on Channel 30 (UHF)
5-7](#__RefHeading___Toc119201848)

[Figure 5‑6. Required CNR Versus Noise Figure
5-7](#__RefHeading___Toc119201849)

[Figure 6‑1. Performance Against 47 RF Captures
6-6](#__RefHeading___Toc119201850)

[Figure 6‑2. White Noise Threshold Versus Multipath Performance
6-6](#__RefHeading___Toc119201851)

[Figure A‑1. Block Diagram of Test Configuration for Required CNR and RF
Capture Tests A-13](#__RefHeading___Toc118693155)

[Figure A‑2. Block Diagram of Test Configuration for Minimum Signal at
TOV A-13](#__RefHeading___Toc118693156)

[Figure A‑3. Frequency Response of Each Port
A-14](#__RefHeading___Toc118693157)

[Figure A‑4. Effect of Load Impedance Mismatch
A-14](#__RefHeading___Toc118693158)

[Figure A‑5. Calibration Connection for Test Setup for Required CNR and
RF Capture Tests A-15](#__RefHeading___Toc118693159)

[Figure A‑6. Spectra of Injected Signal and Noise at 15-dB CNR
A-15](#__RefHeading___Toc118693160)

**TABLES**

[Table 1‑1. Planning Factors for DTV Reception Prediction
1-4](#__RefHeading___Toc118693178)

[Table 2‑1. DTV Receiver Samples 2-3](#__RefHeading___Toc118693179)

[Table 3‑1. Statistics of White Noise Threshold
3-3](#__RefHeading___Toc118693180)

[Table 3‑2. Product-Type/Price Variations of White Noise Threshold
3-4](#__RefHeading___Toc118693181)

[Table 3‑3. Correlation Coefficient of White Noise Threshold with Price
3-4](#__RefHeading___Toc118693182)

[Table 4‑1. Statistics of Minimum Signal Level at TOV
4-2](#__RefHeading___Toc118693183)

[Table 4‑2. Product-Type/Price Variations of Minimum Signal at TOV
4-4](#__RefHeading___Toc118693184)

[Table 4‑3. Correlation Coefficient of Minimum Signal at TOV with Price
4-4](#__RefHeading___Toc118693185)

[Table 5‑1. Statistics of Receiver Noise Figure
5-2](#__RefHeading___Toc118693186)

[Table 5‑2. Product-Type/Price Variations of Receiver Noise Figure
5-3](#__RefHeading___Toc118693187)

[Table 5‑3. Correlation Coefficient of Receiver Noise Figure with Price
5-4](#__RefHeading___Toc118693188)

[Table 6‑1. Number of Captures Successfully Played By Each Performance
Tier 6-3](#__RefHeading___Toc118693189)

[Table 8‑1. Net Performance for Unimpaired Signal Relative to OET-69
Model 8-4](#__RefHeading___Toc118693190)

[Table 8‑2. Planning Factor Measurements with Unimpaired Signal
8-4](#__RefHeading___Toc118693191)

[Table A‑1. Equipment List A-12](#__RefHeading___Toc118693192)

[Table B‑1. RF Field Captures B-2](#__RefHeading___Toc118693193)

# EXECUTIVE SUMMARY {#executive-summary .unnumbered}

This report presents the results of laboratory tests of over-the-air
digital (ATSC/8-VSB[^269]) reception performance of 28 consumer digital
television (DTV) receivers. The tests were performed to provide an
empirical basis for answering questions about DTV reception capability
that derive from study requirements imposed by Congress as part of the
*"Satellite Home Viewer Extension and Reauthorization Act of 2004"*
(SHVERA). The Act requires that the FCC conduct a six-element study. The
element relevant to this report is as follows:

> *"consider whether ... there is a wide variation in the ability of
> reasonably-priced consumer digital television sets to receive
> over-the-air signals, such that at a given signal strength some may be
> able to display high-quality pictures while others cannot, whether
> such variation is related to the price of the television set, and
> whether such variation should be factored into setting a standard for
> determining whether a household is unserved by an adequate digital
> signal."*

## Samples {#samples .unnumbered}

Two categories of DTV receivers were acquired for this project: digital
set-top boxes (STBs) and DTVs with integrated over-the-air ATSC tuners.
All receivers are standard, off-the-shelf consumer products currently on
the market. STBs were included in the study because connection of an STB
to an existing television represents the lowest-cost alternative for DTV
reception. The measurement results in this document are reported by
category (STB or integrated DTVs) and, within the DTV category, by price
range (\$370 - \$1000, \$1001 - \$2000, and \$2001 - \$4200). Brands and
model numbers are not reported.

## Test Results {#test-results .unnumbered}

The tests performed for this report were laboratory-based measurements
emulating two types of over-the-air reception conditions for DTV
receivers:

> \(1\) Unimpaired signal (i.e., no multipath) \[Chapters 3 -- 5\], and
>
> \(2\) Signal impaired by multipath (ghosts) \[Chapter 6\].

The unimpaired signal measurements can be used to quantitatively predict
receiver performance under benign reception conditions---i.e., with
little multipath or interference. The multipath tests, which focus
primarily on particularly difficult multipath conditions, provide a
basis for comparing the ability of different DTV receivers to handle
difficult multipath conditions. A link between these laboratory-based
measurements and earlier FCC field-test data provides a basis for
anchoring the multipath results to representative, real-world reception
conditions \[Chapter 7\].

### Benign Multipath Conditions

Overall performance under benign reception conditions is indicated by
minimum signal level at the threshold of visibility of errors (TOV) for
each receiver. The median measured values of this parameter across all
of the tested consumer DTV receivers were -82.2 dBm, -83.2 dBm, and
-83.9 dBm, respectively, in the low-VHF, high-VHF, and UHF bands. These
values comply, within measurement accuracy, with the ‑83 dBm minimum
performance standard recommended by the ATSC. The corresponding medians
for just the low-cost category of DTVs (-83.3 dBm, -83.4 dBm, and
-84.1 dBm, respectively) were very slightly better than the medians
across all of the receiver categories.

OET Bulletin No. 69, *"Longley-Rice Methodology for Evaluating TV
Coverage and Interference"*, presents a methodology for predicting
whether a household is served by a given broadcast signal. The DTV
receiver model in that bulletin predicts minimum signal levels at TOV of
-81.0 dBm and -84.0 dBm for VHF and UHF, respectively. While the test
results presented in this report---together with data based on earlier
FCC field tests---could be used to fine tune those parameters, the net
effect of such changes would be small; consequently, no compelling
reason is seen for such fine tuning.

Variation in minimum signal at TOV among the receivers was found to be
moderately high in the low-VHF band, but small in the high-VHF and UHF
bands.

In the low VHF band (as represented by TV channel 3 in these tests), the
moderately high variability in performance among the samples is
indicated by the 3.7‑dB standard deviation among the receivers and the
fact that two same-brand receivers exhibited performance significantly
worse than the median---by 11 and 12 dB. (It is noted that, absent those
two receivers, the standard deviation would have been a more modest
2.3 dB.)

Though the performance variation among the receivers in the low VHF band
was moderately high, no statistically significant
[price-dependence]{.underline} of that variation was found. In fact, the
median performance of the low-cost TVs was slightly better than that of
either the mid-priced or high-priced TVs. The median performance of the
tested set-top boxes was poorer than that of the integrated DTVs by
2.3 dB, though it must be noted that these were older designs (2004 and
earlier models that were still on the market at the time of this report)
than the integrated DTVs.

In the high-VHF and the UHF bands (represented in the tests by channels
10 and 30, respectively), the variation in reception performance among
the tested receivers was small---as indicated by the 1.6‑dB standard
deviation in the high-VHF band and 0.9 dB in the UHF band. The variation
of performance with price was judged to be both small and not
statistically significant. The median performance of the high-cost TVs
differed from that of the low-cost TVs by less that 0.2 dB. Set top
boxes exhibited median performance 0.6 dB and 0.7 dB worse than the
median of all TVs in the low-VHF and UHF bands, respectively.

Most of the variation in reception performance among the tested
receivers was due to differences in *effective* noise figure rather than
in the carrier-to-noise ratio (CNR) required for successful
demodulation. The noise figure variations were larger than the
required-CNR variations by factors ranging from 4, in the UHF band, to
16, in the low-VHF band.

### Difficult Multipath Conditions

The tested receivers fall into two distinct tiers of multipath-handling
capability---the upper tier representing a significant performance
improvement associated with at least two companies' newest generation of
demodulator chips. While the difference in ability to handle difficult
multipath conditions between the two tiers is large, linkage of the
current results with earlier field test results (Chapter 7) suggests
that the observed performance differences are of no consequence in the
vast majority of reception locations, if an outdoor, mast-mounted
antenna is used. When an indoor antenna is used, the linkage suggests
that the observed performance differences would be significant in many,
but probably not most, locations.

Given that both tiers of performance appeared in all three price ranges
of DTVs, there appears to be no price dependence of multipath
performance; however, there was a complete absence of upper-tier
performers among the tested set-top boxes. This absence is attributed to
the older designs of the set-top box products---all of which were
introduced in the year 2004 or earlier. Among the tested DTV receivers,
none that were introduced before March 2005 were found to exhibit
upper-tier performance, whereas 48 percent of those introduced in or
after that month performed at the upper tier level.

# ** ****INTRODUCTION** {#introduction .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

## BACKGROUND {#background .unnumbered}

This report presents the results of laboratory tests of terrestrial
over-the-air digital (ATSC/8-VSB[^270]) reception performance of 28
consumer digital television (DTV) receivers. Though the tests involve
[terrestrial]{.underline} reception performance, the tests were
performed to provide an empirical basis for answering questions about
DTV reception capability that derive from study requirements imposed by
Congress as part of the *"Satellite Home Viewer Extension and
Reauthorization Act of 2004"* (SHVERA).

SHVERA, passed by Congress in December 2004, extends and amends the
*"Satellite Home Viewer Act of 1994"*. The Act allows satellite
communications providers to provide broadcast programming to satellite
subscribers that are unserved by local---over-the-air---broadcast
stations.

Section 204 of SHVERA requires that the Commission conduct an inquiry
regarding "whether, for purposes of identifying if a household is
unserved by an adequate digital signal under section 119(d)(10) of title
17, United States Code, the digital signal strength standard in section
73.622(e)(1) of title 47, Code of Federal Regulations, or the testing
procedures in section 73.686(d) of title 47, Code of Federal
Regulations, such statutes or regulations should be revised to take into
account the types of antennas that are available to consumers."

The act specifies six areas of inquiry. The relevant area for this
report is the one that relates to characteristics of consumer digital
television receivers. It states that the inquiry should

> *"consider whether ... there is a wide variation in the ability of
> reasonably-priced consumer digital television sets to receive
> over-the-air signals, such that at a given signal strength some may be
> able to display high-quality pictures while others cannot, whether
> such variation is related to the price of the television set, and
> whether such variation should be factored into setting a standard for
> determining whether a household is unserved by an adequate digital
> signal."*

The Act requires that the results and recommendations from this inquiry
be reported to the Committee on Energy and Commerce of the House of
Representatives and the Committee on Commerce, Science, and
Transportation of the Senate.

## Objectives {#objectives .unnumbered}

This report presents the results of a measurement program that was
undertaken by the Technical Research Branch of the FCC Laboratory in
order to address those portions of the SHVERA-required inquiry that
involve characteristics of consumer digital television receivers.
Accordingly, the objectives are to provide an empirical basis for
answering three questions.

\(1\) Is there a wide variation in the ability of reasonably-priced
consumer digital television sets to receive over-the-air signals, such
that at a given signal strength some may be able to display high-quality
pictures while others cannot?

\(2\) Is such variation is related to the price of the television set?

\(3\) Should such variation be factored into setting a standard for
determining whether a household is unserved by an adequate digital
signal.

## Ability to Receive Signals {#ability-to-receive-signals .unnumbered}

The ability of a television receiver to receive over-the-air signals and
display a high quality picture is influenced by the level and quality of
the television signal reaching its antenna input terminal from the
antenna downlead, the amount of noise or interference reaching the input
terminal, and the properties of the television receiver---including the
amount of noise created by the input circuitry of the television
receiver.

### Threshold

When a television receives a signal from an [analog]{.underline} TV
station using the NTSC transmission system that has been employed in the
U.S. for decades, the TV exhibits a noisy picture at low signal levels.
The noise is frequently termed "snow". If the signal level increases,
the amount of snow in the picture decreases very gradually. If signal
level is increased until it exceeds the internally generated noise of
the television's input circuits by 34 dB (carrier-to-noise ratio =
34 dB), the picture level improves to the point that typical viewers
consider the noise to be "slightly annoying".[^271] The noise remains
perceptible but is not considered annoying at a 40-43 dB
carrier-to-noise ratio,[^272] and ceases to be visible at all when the
carrier-to-noise ratio (CNR) is 51 dB.[^273]

When a digital television receives a signal from a [digital]{.underline}
television station using the ATSC transmission system adopted by the FCC
for terrestrial DTV broadcasts in the U.S., the transition from no
picture to a virtually perfect picture occurs over a much narrower range
of signal levels. Once a threshold signal level is reached, the TV
picture is virtually perfect---limited only by the quality of the source
material and the characteristics of the television display (for example,
the picture tube and associated image forming circuits and software).
This threshold corresponds to a carrier-to-noise ratio of only about
15 dB. If the signal is reduced below this threshold value, visible
errors begin to occur in the picture---becoming more frequent with
further reductions in signal level, until the picture becomes
essentially unusable at a level only about 1 dB below the threshold.

Part of the task of determining the ability of a DTV receiver to receive
over-the-air signals is to determine this threshold when only a DTV
signal is applied to the antenna terminal (i.e., without any noise or
interfering signals), as well as when both a DTV signal and source of
electronic noise are applied simultaneously to the antenna terminal. The
resulting measured parameters are the minimum signal at the threshold of
visibility of errors (TOV) and the white noise threshold---also known as
the required carrier-to-noise ratio (CNR).

### Multipath

A propagation phenomenon called multipath causes very different effects
for analog versus digital television transmissions. Multipath is caused
by the fact that the broadcast signal may reach the television antenna
through several propagation paths that reflect off of various natural
and man-made objects. A direct signal path encountering no reflections
may also be present. The reflected signal paths are essentially delayed
versions of the direct-path signal---with the delay being dependent on
the additional distance traveled by each reflected signal.

With analog (NTSC) television, multipath causes one or more "ghost"
images displaced horizontally from the main image. (The term "ghost"
refers to the ghost-like appearance of the displaced image, which
appears as a fainter version of the primary image.) Ghosts can
significantly degrade picture quality even when the primary signal
strength is quite high. In analog television, control of ghosts is
usually accomplished by using a directional antenna oriented to
selectively receive the stronger signal (usually the direct path signal)
and to reject---at least to some extent---other paths, for which signals
typically arrive from other directions.

With digital (ATSC) television, multipath does not cause ghost-like
displaced images on the screen, though the term "ghost" is still used to
describe multipath propagation. Instead, a weak ghost may have no effect
on the picture at all. A somewhat stronger ghost may cause picture
impairments such as blockiness or freeze frames. An even stronger ghost
can completely prevent the television from decoding the digital data
necessary to produce a picture and sound. Consequently, all ATSC
television receivers contain a circuit called an equalizer, the function
of which is to adaptively cancel ghosts. If the equalizer reduces the
amplitudes of all but one signal path to a sufficiently low level, the
picture will be displayed with no impairment at all. If the cancellation
is insufficient, the TV may fail to produce a picture even when signal
level is very strong.

Equalizer performance has been one of the primary areas of technological
improvement as DTV receivers progress from one generation to the next.
With advances in equalizer technology, significant improvements have
been made in the ability to cancel larger amplitude ghosts, ghosts with
larger delays relative to the main signal, and ghost signals arriving
earlier than the main signal (in cases for which the direct path signal
is either absent or weaker than reflected signals). Other researchers
have noted a high degree of improvement in multipath-handling capability
of the latest generation of equalizer technology.[^274]

Consequently, a part of determining the ability of a DTV receiver to
receive over-the-air signals is to characterize the ability of the
receiver to handle various multipath conditions. For this study, that
characterization was performed by feeding the antenna input terminal of
the TV with signals that were recorded from television antennas at
various locations in New York City and Washington, D.C.

It is also noted that, for DTV receivers that are compliant with the
EIA/CEA-909 Antenna Control Interface specification, smart antenna
technology can mitigate the effects of multipath, as well as certain
other reception issues, through automatic optimization of various
antenna parameters such as the effective pointing direction,
polarization, and amplifier gain on a per-channel basis. The ATSC, in
its "ATSC Recommended Practice: Receiver Performance Guidelines",
recommends that "in addition to the other guidelines contained herein
for the handling of signal conditions that are experienced in the field,
consideration of a receiver-controlled antenna, as enabled by CEA-909,
is recommended" and notes that such a controllable antenna can "work in
conjunction with a receiver's equalizer, tuner, and demodulator to
improve reception under conditions of multipath and unusually weak or
strong signals."[^275] This interface was included in only one of the
DTV receivers tested for this report. Though the smart antenna
functionality was not formally tested, we observed that it did offer a
user-friendly way to optimize TV reception. Not only does it simplify
the initial setup of the DTV for the consumer, but it also provides the
advantage of instantaneously switching the antenna pointing
direction---electronically---whenever the TV channel is changed.

## Standard for Determining Whether a Household is Unserved {#standard-for-determining-whether-a-household-is-unserved .unnumbered}

Section 73.622(e) of the Commission's rules, Code of Federal Regulations
(CFR) 47, specifies a method for determining the service area of a DTV
broadcast station based on OET Bulletin No. 69, *"Longley-Rice
Methodology for Evaluating TV Coverage and Interference"*---hereafter
referred to as OET‑69. The bulletin defines the method for predicting
field strength created at any given location by a television
transmitter. It further defines television reception system "planning
factors" that can be used to determine the field strength required for
successful DTV reception.

The FCC's defined reception planning factors include antenna gain,
signal loss in the down-lead cable connecting the antenna to the
television receiver, noise figure of the receiver, and required
carrier-to-noise ratio. The latter two factors are functions of the DTV
receiver and are a primary focus of the measurements conducted for this
report. These parameters, as specified by OET‑69, are shown in
Table 1‑1.

[]{#__RefHeading___Toc118693178 .anchor}Table 1‑1. Planning Factors for
DTV Reception Prediction

  ------------------------------- ------------ ---------- ---------- ----------
  **Planning Factor**             **Symbol**   **Low      **High     **UHF**
                                               VHF**      VHF**      

  Geometric Mean Frequency (MHz)  F            69         194        615

  System noise figure (dB)        N~S~         10         10         7

  Required Carrier-to-Noise ratio C/N          15.2 (15)  15.2 (15)  15.2 (15)
  (dB)                                                               
  ------------------------------- ------------ ---------- ---------- ----------

> Note: The Final Technical Report of the FCC Advisory Committee on
> Advanced Television Service listed 15.19 dB as the C/N for the Grand
> Alliance DTV receiver.[^276] In OET-69 this value is rounded to the
> nearest dB---i.e., 15 dB; however, in identifying "OET-69" planning
> factors and predictions for this report, we will round to the nearest
> tenth of a dB and use 15.2 dB. Combining this C/N value with the
> system noise figures and the ‑106.2 dBm thermal noise level specified
> in OET-69, yields a minimum signal power at TOV of ‑81.0 dBm in VHF
> and ‑84.0 dBm in UHF.

Although OET-69 was developed for defining service areas for
channel-allocation purposes, the same approach could be used for initial
prediction of whether a household is unserved by an adequate digital
signal for SHVERA purposes. Consequently, this report will evaluate the
validity of the OET-69 planning factors based on measurements of
current-model consumer DTVs.

## Overview {#overview .unnumbered}

The laboratory-based measurements performed for this report emulated two
types of over-the-air reception conditions for DTV receivers:

> \(1\) Unimpaired signal (i.e., no multipath) \[Chapters 3 -- 5\], and
>
> \(2\) Signal impaired by multipath (ghosts) \[Chapter 6\]---focusing
> on particularly difficult multipath conditions.

The unimpaired signal measurements can be used to quantitatively predict
receiver performance under benign reception conditions---i.e., with
little multipath (commonly referred to as a white Gaussian channel). The
multipath tests provide a basis for comparing the ability of different
DTV receivers to handle difficult multipath conditions. Chapter 7 links
the new, laboratory-based measurements to earlier FCC field-test data as
a basis for anchoring the multipath results to representative,
real-world reception conditions.

# ** ****SCOPE AND APPROACH** {#scope-and-approach .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

## Scope of Testing {#scope-of-testing .unnumbered}

The parameters measured for this report to characterize each television
receiver are as follows:

\(1\) minimum signal at the threshold of visibility of errors (TOV);

\(2\) the white noise threshold (defined at the TOV)---also known as the
required carrier-to-noise ratio (CNR); and,

\(3\) the number of ATSC-recommended field ensembles (RF captures) that
can be successfully demodulated by the receiver.

The first two of these are measures of sensitivity of the receiver for
an unimpaired signal. The latter characterizes the ability of the
receiver to handle difficult multipath conditions.

While these measurements provide a basis for achieving the stated
objectives of this report, it should be recognized that they do not
fully characterize the over-the-air reception capability of a DTV
receiver. The ATSC recommends that DTV receivers be evaluated on the
basis of a wide variety of criteria that are not included in this
report, such as multi-signal overload, tolerance to phase noise,
co-channel rejection, adjacent-channel rejection, burst noise rejection,
and a more complete characterization of multipath capability.[^277]

## Test Samples {#test-samples .unnumbered}

Given the objectives of determining whether there is a wide variation in
reception performance of [reasonably-priced]{.underline} consumer
digital television receivers and determining whether the variation is
related to price of the receiver, an effort was made to select samples
over a range of prices, but with emphasis on the lower end of the price
range.

Two categories of DTV receivers were acquired for this project: digital
set-top boxes (STBs) and DTVs with integrated over-the-air ATSC tuners.
The selected receivers are standard, off-the-shelf consumer products
currently on the market.

STBs were included in the study because connection of a set-top box to
an existing television represents the lowest-cost alternative for DTV
reception. Each STB includes a digital tuner and outputs necessary to
drive high-definition television displays (through component video, DVI,
or HDMI connections) and standard-resolution analog televisions (through
a composite video output or an S-Video \[Y-C\] output). When driving a
conventional analog television, high definition programming is
down-converted to the resolution of the TV. Besides their use in
enabling digital reception with analog TVs, set-top boxes are also
useful to consumers who have high-definition, digital-ready televisions
that do not include an ATSC tuner.

### Selection Criteria

In selecting receivers for this study, several criteria were applied.

1\. A total of about 30 samples was planned for the tests in order to
balance the need for a large enough sample to provide a degree of
statistical confidence in the results with the need to limit sample size
for practical reasons.

2\. Recently introduced models were selected, where possible, especially
if the manufacturer expected a change in over-the-air digital reception
performance with the newer model; in some cases this meant requesting a
model that was not available when the tests were begun, but was
delivered late in the test cycle or, in two cases, was delivered too
late to include in this report.

3\. An attempt was made to obtain one set-top box from most companies
that manufacture one. (All set-top box models were of relatively old
designs---introduced in the year 2004 or, in one case, 2003---even
though they were the latest models available on the market.)

4\. One DTV having an integrated ATSC tuner was selected from at or near
the low-price end of each manufacturer's product line.

5\. In addition, a mid or mid-to-high priced DTV having an integrated
ATSC tuner was requested from many of the manufacturers.

### Overview of the Samples

Table 2-1 summarizes the characteristics of the DTV receivers in the
test sample. The receivers, which represent 16 brand names, are divided
by product type---set-top box versus DTV with integrated ATSC
tuner---and, within the DTV type, by price range. In most cases, prices
were determined by selecting the median price from a FROOGLE search for
each product conducted in August, 2005. Four products not found through
FROOGLE were priced through Wal-Mart in August, 2005, and one was priced
through Amazon in September, 2005.

[]{#__RefHeading___Toc118693179 .anchor}Table 2‑1. DTV Receiver Samples

+-----------------+--------+--------+------------+-------------------+
| **Sample Type** | **     | **D    | **Display  | **Display         |
|                 | Number | isplay | Aspect     | Technology**      |
|                 | of     | Size** | Ratio**    |                   |
|                 | Sam    |        |            |                   |
|                 | ples** |        |            |                   |
+-----------------+--------+--------+------------+-------------------+
| **Set-Top Box   | 5      | N/A    | N/A        | N/A               |
| (STB)**         |        |        |            |                   |
+-----------------+--------+--------+------------+-------------------+
| **DTV with      |        |        |            |                   |
| Integrated ATSC |        |        |            |                   |
| Digital         |        |        |            |                   |
| Tuner:**        |        |        |            |                   |
+-----------------+--------+--------+------------+-------------------+
| 1.  \$370 -     | 6      | 26" -- | 4:3 or     | Direct-View CRT   |
|     \$1000      |        | 36"    | 16:9       |                   |
+-----------------+--------+--------+------------+-------------------+
| 2.  \$1001 -    | 8      | 26" -- | 16:9       | Direct-View LCD,  |
|     \$2000      |        | 52"    |            |                   |
|                 |        |        |            | Plasma,           |
|                 |        |        |            |                   |
|                 |        |        |            | CRT Rear          |
|                 |        |        |            | Projection,       |
|                 |        |        |            |                   |
|                 |        |        |            | DLP Rear          |
|                 |        |        |            | Projection,       |
|                 |        |        |            |                   |
|                 |        |        |            | LCD Rear          |
|                 |        |        |            | Projection        |
+-----------------+--------+--------+------------+-------------------+
| 3.  \$2001 -    | 9      | 32" -- | 16:9       | Direct-View LCD,  |
|     \$4200      |        | 62"    |            |                   |
|                 |        |        |            | Plasma,           |
|                 |        |        |            |                   |
|                 |        |        |            | DLP Rear          |
|                 |        |        |            | Projection,       |
|                 |        |        |            |                   |
|                 |        |        |            | LCD Rear          |
|                 |        |        |            | Projection        |
+-----------------+--------+--------+------------+-------------------+
| **TOTAL**       | **28** |        |            |                   |
+-----------------+--------+--------+------------+-------------------+

*Notes:*

*\--CRT = cathode ray tube (conventional picture tube)*

*\--DLP = digital light processing*

*\--LCD = liquid crystal display*

In order to avoid revealing specific brands or models of the samples,
test results presented in this document are reported by product type and
price categories and by a letter and number code assigned to each
product. The letter indicates product brand---with letters randomly
assigned to brand names. Within each brand, a number is assigned in
order of increasing price. For example, the designations A1, A2, and A3
represent three same-brand receivers listed in order of increasing
price.

## Test Philosophy and Approach {#test-philosophy-and-approach .unnumbered}

### Laboratory Versus Field Testing

All testing was performed in the laboratory using either
laboratory-generated signals or signals that had been digitally recorded
from television antennas at various test sites in New York City and the
Washington, DC area, and were replayed in the laboratory using equipment
that allowed the signal to translated to any desired TV channel number
for playback.

This test method offered two advantages over field-testing of the
receivers:

\(1\) the cost and time required for testing was far lower for lab-based
tests than for field testing, which would have required transporting the
bulky, heavy TVs and test equipment to multiple sites; (the TVs alone
weighed 2200 pounds and had a combined width of 82 feet), and,

\(2\) tests with signals that are generated or recreated (by playback)
in the laboratory are expected to yield more consistent results than are
field tests, in which received signal characteristics may vary
significantly over the course of testing 28 receivers.

### TV Channel Selection

For testing minimum signal at TOV, channels 3, 10, and 30 were selected
to represent the low-VHF, high-VHF, and UHF bands, respectively.
Selection was based on relatively central locations within the
respective bands and an absence of local TV broadcasts on these
channels.

Other tests, for which results were not expected to vary with channel,
were performed on TV channel 30.

### Operation and Connection of Samples

For receivers having multiple antenna inputs that could handle ATSC
signals, only the input labeled "antenna A" or "antenna 1" was tested.
For receivers having a radio frequency (RF) output associated with the
selected antenna input, the output was externally terminated in 75 ohms.

Each set-top box was operated in a high definition mode and was
connected to a high definition monitor by means of a component video
output.

### Test Configurations

All test and measurement setups maintained a 50-ohm impedance
throughout, except at the signal source and the consumer TV inputs,
which were each specified to be nominally 75 ohms. (An older,
instrumented reference receiver included in one test had a 50-ohm input
impedance.) The 75‑ohm devices were matched to the rest of the test
setup through impedance-matching pads, except that, for one of the test
setups, an impedance transformer was used at the signal source to reduce
losses. In addition to the impedance-matching pads, 50-ohm attenuator
pads were used at various places throughout the test setups to reduce
the effects of any impedance mismatches at places where such mismatches
were considered likely or would be expected to have a significant
impact.

The minimum signal at TOV is the only measured parameter for which
absolute accuracy of the measurement equipment was a factor;
consequently, that parameter was tested by connecting a signal
source---through appropriate pads, step attenuators, and cables---to one
TV at a time. After adjusting the signal attenuation to achieve TOV on
the TV, the output of the entire setup---with the exception of the final
impedance-matching pad, was connected to a vector signal analyzer for
measurement of the signal level. The only correction then necessary to
determine the input to the TV was to subtract the attenuation of the
impedance-matching pad from the measured level. That attenuation was
measured separately.

For the measuring white noise threshold (required CNR), absolute
measurement accuracy was less critical since the value to be determined
was the ratio of a signal level to a noise level. To maintain accuracy
of the ratio, both measurements were made with the vector signal
analyzer on the same amplitude range. The reduced criticality of
absolute measurement accuracy enabled the use of a splitter to
simultaneously deliver the signal and noise to as many as eight TVs and
to the vector signal analyzer for the quantitative measurements. The
simultaneous connection reduced measurement time by allowing TV channel
scans (required by many of the TVs when a signal was changed) to be
performed simultaneously on multiple TVs and by reducing the need to
repeatedly disconnect and reconnect cables.

Tests of the ability of each receiver to handle the multipath conditions
represented by the ATSC-recommended field ensembles (RF captures) also
did not require absolute accuracy in measuring the applied signal
levels; consequently, the same splitter arrangement was used. The
approach was to apply a signal level well above the minimum signal level
at TOV (by about 50 dB) so that signal level was not an issue.

Details on the test methods and configurations are presented in Appendix
A.

### Thresholds

For both types of threshold measurements (required CNR and minimum
signal at TOV), the reported value is the level measured on the maximum
attenuation step (lowest signal level) that resulted in no observed
errors in 60 seconds of viewing time. The threshold level at which the
60-second viewing time condition was met was nominally somewhere between
that reported level and the next higher attenuation level (next lower
signal level step); consequently, this approach can be expected to
overestimate required signal levels by an average of half the attenuator
step size of 0.1 dB. One could therefore justify subtraction of 0.05 dB
from the measured signal levels. This subtraction was not performed, in
part to compensate for the fact that TOV measurements are often based on
longer observation times than the 60 seconds used in these tests.

# ** ****WHITE-NOISE THRESHOLD MEASUREMENTS (REQUIRED CARRIER-TO-NOISE RATIO)** {#white-noise-threshold-measurements-required-carrier-to-noise-ratio .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

White-noise threshold refers to the ratio of signal ("carrier") power to
noise power within the 6-MHz bandwidth of a television channel when both
an unimpaired signal (no multipath) and broadband ("white") Gaussian
noise are simultaneously applied to the antenna terminal of a DTV
receiver and the signal or noise power is adjusted to the point at which
observable errors in the DTV picture just become invisible---i.e., the
threshold of visibility (TOV). This is the carrier-to-noise ratio (CNR)
required to produce a "clean" DTV picture. The definition assumes that
the applied noise power is sufficiently higher than any noise generated
internally by the DTV receiver circuitry so as to make the internally
generated noise negligible.

At CNR levels below the white-noise threshold, picture quality rapidly
degrades to the point that, only about one dB below the white-noise
threshold, the picture is typically unwatchable or nonexistent.

At CNR levels above the white-noise threshold, the picture is
essentially free of defects that are related to transmission and
reception of the signal.

White noise threshold is of direct interest because it indicates the
ability of a digital television to receive and process a DTV signal in
the presence of high ambient noise levels---assuming that the signal is
not significantly impaired by multipath or interference and that the
ambient noise has characteristics similar to white Gaussian noise. In
cases where the ambient environment is quiet, white noise threshold is
useful in understanding the reception performance of a DTV receiver in
the presence of noise that is internally generated within the input
circuits of the receiver.

The results of this chapter apply only to signals that are unimpaired by
multipath. In the presence of multipath, a higher CNR may be required to
produce a clean picture. While the measurements performed for this
report do not address such an increase, the topic is discussed in
Chapter 7, based on earlier field test results.

## Measurement Method {#measurement-method .unnumbered}

White-threshold of each receiver was measured by simultaneously
injecting into the antenna port of the receiver both an unimpaired
(e.g., no multipath) ATSC signal on channel 30 and white noise from a
noise generator. A nine-way splitter feeding equal-length,
well-shielded, low-loss cables allowed the same combination of signal
plus noise to be applied simultaneously to as many as eight DTV
receivers and a vector signal analyzer that was used for the
measurements. As a consistency check, receiver D3 was included in each
group of eight receivers that were tested; measurements of D3 were
consistent within ±0.1 dB.

Impedance-matching attenuator pads (50 ohms to 75 ohms, 5.8 dB power
attenuation) at each TV receiver served to match the nominal 75-ohm
impedance of the receiver antenna ports to the rest of the 50-ohm
measurement system and, through the attenuation it provided, served to
reduce the impact of any deviations from that nominal TV input
impedance. At the vector signal analyzer, a 6-dB, 50-ohm attenuator
served a similar function.

Because the small differences in loss between the various splitter
outputs, cables, and pads can be expected to equally affect both the
signal and the noise, the measured CNR is not affected by such
differences.

The signal source for these tests was an RF player (Sencore RFP-910)
playing the "Hawaii_ReferenceA" file supplied with the player. The file
consisted of a 25-second repeating loop of motion video scenes shot at
several outdoor locations. At each loop restart, most DTV receivers
exhibited video errors related to re-locking to the signal;
consequently, the first three seconds of each loop were not included in
the observation time. (An ATSC signal generator, rather than the RF
player, had been intended for these tests. Use of the generator would
have avoided issues with loop restart time, but the generator was
abandoned due to degraded signal quality.) The signal was amplified
before splitting it. A step attenuator following the amplifier was used
to adjust the signal level.

The noise source was a noise generator (Noise/Com UFX-7110) band limited
to 700 MHz, well above the frequency of TV channel 30, thus leaving the
spectrum flat across the bandwidth of the selected TV channel. The
injected noise power was set nominally to -70 dBm within the 6-MHz
bandwidth of channel 30---about 29 dB above the internally generated
noise of a typical DTV receiver---by using a step attenuator with 0.1-dB
steps. The noise power measurement (usually within 0.05 dB of -70 dBm)
was then recorded. The actual injected noise power was computed by
subtracting the effect of instrument noise, which was about 26 dB below
the injected noise power.

Signal level was increased in 0.1-dB steps until the TV picture could be
viewed for 60 seconds without observing a video error (excluding loop
restart periods, as noted above). A measurement was then made of the
combined power of both the injected signal and the injected noise, and
the signal power was computed by subtracting the noise power (in linear
power units); since the noise power at the threshold was typically about
15 dB below the signal, the net signal power was only about 0.1 dB below
the measured total power.

Further details on the measurement procedure are contained in Appendix
A.

## Format of The Bar Graph Data {#format-of-the-bar-graph-data .unnumbered}

The measurement results are presented in bar-graph form in Figure 3-1.
That format, explained here, is also used in subsequent chapters to
present other results.

Each bar on the graph represents performance of one DTV receiver. The
"Better"/"Worse" labels on the vertical axis indicate that, for the
plotted parameter, lower values represent better performance.

Each receiver is designated by a letter and a numeral. The letters,
which were assigned randomly, represent brand names. Thus, receivers A1,
A2, and A3 are all of the same brand.

The receivers are grouped into categories. The first category is set-top
boxes (STBs). The remaining categories are three different price ranges
of DTVs. Within each group, the results are listed in order of the
randomly assigned brand code letters rather than in price order. This
approach was taken so that individual products could not be identified
based on price.

The solid blue line represents the median result across all tested
receivers. The dashed blue line represents the median result within each
category. The dashed red line represents the mean result within each
category. A wider dashed green line represents the value of the planning
factor assigned to the measured parameter by OET-69.

## Results {#results .unnumbered}

The results of the white-noise threshold measurements are shown in
Figure 3-1.

### Nominal Performance and Variation Among Samples

Statistics of the white-noise threshold (required CNR) are shown in
Table 3-1. The white noise threshold of the median receiver---measured
across all tested receivers---is 15.3 dB. This is only 0.1 dB above
(worse than) the corresponding planning factor value in OET-69. (Because
the CNR was determined from the ratio of two power measurements
performed on the same amplitude range of the same measuring instrument,
it's value is not affected by absolute calibration accuracy of the
instrument and is therefore expected to be accurate to within
0.2 dB.[^278])

[]{#__RefHeading___Toc118693180 .anchor}Table 3‑1. Statistics of White
Noise Threshold

  ------------------------------------------------------------ -----------
  **WHITE NOISE THRESHOLD**                                    

  Median across all receivers (dBm)                            15.3

  Median re OET-69 planning factors                            0.1

  Deviations of receivers from median (dB)                     

  \--Best performing receiver (dB)                             -0.4

  \--Worst performing receiver (dB)                            0.5

  \--89th percentile receiver (dB)                             0.3

  Standard deviation (dB)                                      0.2

  Total span from best to worst receiver (dB)                  0.8[^279]
  ------------------------------------------------------------ -----------

The variations among receivers were quite small. The standard deviation
of the CNR measurements across all receivers was 0.2 dB. The total span
from best to worst performing receiver was 0.8 dB, with the worst
measured white noise threshold being 0.5 dB above the median value.

### Variation with Price and Type Category

#### Magnitude of Observed Variations With Product Type and Price {#magnitude-of-observed-variations-with-product-type-and-price .unnumbered}

The observed performance variations among the product type and price
categories were also small, as shown in Table 3-2. The least expensive
way to receive a DTV broadcast is to purchase a digital set-top box and
connect it to an existing TV. Median performance of set-top boxes was
only 0.1 dB worse than the overall median. The median low-cost and
mid-cost DTVs performed at the overall median, and the median high-cost
DTV performance was 0.2 dB better than the overall median.

[]{#__RefHeading___Toc118693181 .anchor}Table 3‑2. Product-Type/Price
Variations of White Noise Threshold

  ---------------------------------------------------------------- ------
  **WHITE NOISE THRESHOLD**                                        

  Median of Set-Top Boxes re Overall Median (dB)                   0.1

  Median of Low-Price DTVs re Overall Median (dB)                  0.0

  Median of Medium-Price DTVs re Overall Median (dB)               0.0

  Median of High-Price DTVs re Overall Median (dB)                 -0.2
  ---------------------------------------------------------------- ------

#### Statistical Significance of Observed Variations With Product Type and Price {#statistical-significance-of-observed-variations-with-product-type-and-price .unnumbered}

Apparent variations in performance of samples with price can be caused
by random sampling effects even when there is no underlying
performance/price dependence in the overall population; hence, some
means is necessary to determine whether an apparent dependence observed
in the sample is statistically significant.

In the case of measurements of the required CNR for the tested
collection of DTV receivers, the observed variations with price are so
small as to be inconsequential; consequently, assessing the statistical
validity of those variations is hardly necessary. Nonetheless, an
analysis is included here for completeness and to provide a comparative
basis for more significant observed variations that are presented in
subsequent chapters.

As seen in Table 3-3, the Pearson's correlation coefficient between
required CNR and receiver price was computed as -8.6 percent when all
receivers were included and +7.0 percent when only the DTVs (not set-top
boxes) were included. A negative sign indicates that the required CNR
appears to decrease (i.e., improve) with increasing receiver price,
while a positive sign indicates that the required CNR increases (i.e.,
degrades) with increasing price. Determining whether any observed
apparent trend is real or is an artifact of the small sample set used in
the tests requires a statistical assessment.

[]{#__RefHeading___Toc118693182 .anchor}Table 3‑3. Correlation
Coefficient of White Noise Threshold with Price

  ---------------------------------------------------------- ------------
  **Pearson's Correlation Coefficient of White Noise         
  Threshold with Price**                                     

  All Tested Receivers                                       -8.6%

  DTVs Only (no Set-Top Boxes)                               +7.0%
  ---------------------------------------------------------- ------------

The usual method of assessing the statistical significance of given
value of the Pearson's correlation coefficient is to compare the
magnitude of the observed correlation to values in a table of critical
values of the Pearson's correlation coefficient. The technique is used
to determine the likelihood that a correlation as high as that which was
observed might occur randomly, for the selected sample, if there is no
actual correlation between required CNR and receiver price in the larger
population of all DTV receivers. Such a lookup table specifies values as
a function of the "number of degrees of freedom", which is two less than
the total number of samples---*assuming that the samples are
independent*.

For the overall sample size used in this study (28 samples, 26 degrees
of freedom), one can determine from such a table that the magnitude of
an observed correlation coefficient must be 32 percent or higher in
order to ensure that there is no more than a five percent probability
that the observed correlation could result by random sampling effects
from a larger population that has no such correlation. In the case of
the 23 DTVs (i.e., excluding the set-top boxes), the magnitude of an
observed correlation would have to be 35 percent or higher to meet the
same criterion. (These are single-sided probabilities---i.e., the
probability that a correlation magnitude will exceed, in a single
direction, a given correlation value. For example, if the overall
population has no correlation with price, there is a five percent
probability that the correlation of a randomly selected sample of 28
receivers will exceed a 32 percent magnitude with a negative
correlation---indicating [decreasing]{.underline} CNR with increasing
receiver price. There is also a five percent probability of exceeding
that same magnitude with a positive correlation---indicating
[increasing]{.underline} CNR with increasing price.)

It should be noted that these statistical calculations are dependent
upon a number of assumptions, including that the shape of the
probability distribution of the measured parameter is normal (Gaussian),
that the samples were randomly selected, and that the samples are
independent. None of these assumptions is strictly true for the case at
hand. Of particular concern is the independence assumption, because it
is quite likely that some of the receiver samples share critical
subsystems. For example, a given tuner or demodulator design may be used
in more than one of the receivers. The effect of such a commonality
between samples would be to decrease the effective number of degrees of
freedom in the computed Pearson's correlation coefficient. Such a
decrease would increase the magnitude of correlation that would have to
be observed to have a given confidence level in the result.

The observed correlations of -8.6 percent and +7.0 percent in the
white-noise threshold measurements are so small as to provide no
confidence that the small observed variations in performance with price
reflect a real price-dependence in the overall population of DTV
receivers currently on the market.

### Effect of TV Channel

White noise threshold (required CNR) is expected to be dependent on the
demodulator function of a DTV receiver. Since this function occurs after
the tuner heterodynes the incoming RF signal from the frequency band of
the TV channel to an intermediate frequency (IF), one would expect the
white noise threshold to be essentially independent of TV channel
number. Consequently, testing was performed on only one
channel---channel 30.

In testing minimum signal level of the DTV receivers, as reported in the
next chapter, there was a large variation in the results between
channels for some TVs. In order to verify that the variation was not
related to changes in white noise threshold, the white noise threshold
of one DTV receiver was also tested on channel 3. The selected receiver
was G2, the receiver with the largest variation in minimum signal level
across the channels (a 13 dB difference between channels 3 and 30). For
this receiver, the measured white noise thresholds on channels 3 and 30
were 15.6 and 15.5 dB, respectively; this difference is within
measurement error.

[]{#__RefHeading___Toc119201837
.anchor}![](media/image5.wmf){width="6.497916666666667in"
height="4.3in"}

Figure 3‑1. Measured White Noise Threshold of Receivers

# ** ****MINIMUM INPUT SIGNAL MEASUREMENTS** {#minimum-input-signal-measurements .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

Minimum input signal at the threshold of visibility (TOV) is the signal
("carrier") power at the antenna terminal of a DTV receiver when the
signal level is adjusted to the point at which observable errors in the
DTV picture just become invisible. It is a direct measure of sensitivity
of a DTV receiver to weak signals in the absence of significant
externally generated noise or interference---assuming that the input
signal is not significantly impaired by multipath. At input levels below
this threshold level, picture quality rapidly degrades to the point
that, only about one dB below the white-noise threshold, the picture is
typically unwatchable or nonexistent. At input levels above the
threshold, the TV picture is essentially free of defects that are
related to transmission and reception of the signal.

The results of this chapter apply only to signals that are unimpaired by
multipath or interference. In the presence of multipath, a higher signal
level may be required to produce a clean picture. While the measurements
performed for this report do not address such an increase, the topic is
discussed in Chapter 7, based on earlier field test results.

## Measurement Method {#measurement-method-1 .unnumbered}

Because minimum input signal at TOV is an absolute measurement rather
than a ratio, the splitter was not used for these tests. The receivers
were tested sequentially in groups of about eight---with receiver D3
included in each group, as a consistency check; measurements of D3 were
consistent within ±0.3 dB. The results are subject to the absolute
measurement accuracy of the vector signal analyzer, which is specified
as ±1.5 dB maximum and ±0.5 dB typical on the amplitude range that was
used for the measurements;[^280] additional errors due to adjustment for
attenuation of impedance-matching pad---as described below---are
expected to be negligible compared to the VSA tolerance.

The tests were performed on three TV channels---3, 10, and 30---in order
to evaluate performance in the low VHF, high VHF, and UHF bands,
respectively. The selection of those specific channels was based on
avoiding local broadcast channels and selection of a relatively central
channel within each band.

The signal source for these tests was an RF player (Sencore RFP-910)
playing the "Hawaii_ReferenceA" file supplied with the player. The file
consisted of a 25-second repeating loop of motion video scenes shot at
several outdoor locations. At each loop restart, many DTV receivers
exhibited video errors related to re-locking to the signal;
consequently, the first three seconds of each loop were not included in
the observation time. A step attenuator was used to adjust the signal
level. The signal was applied to a single DTV receiver through a
low-loss 50-ohm cable followed by a 10-dB attenuator pad and an
impedance-matching attenuator pad having 5.8 dB power attenuation. The
latter served to match the nominal 75-ohm impedance of the receiver
antenna port to the rest of the 50-ohm measurement system. Both pads
served to minimize reflections that might be caused by any deviation of
receiver input impedance from the nominal.

Signal level was increased in 0.1-dB steps until the TV picture could be
viewed for 60 seconds without observing a video error (excluding loop
restart periods, as noted above). The low-loss cable and 10-dB pad were
then connected to a vector signal analyzer on its most sensitive
amplitude range (-50 dBm) to measure the power of the applied signal.
The 10-dB pad served to minimize reflections that would be caused by any
deviation of the vector signal analyzer input impedance from 50 ohms. A
separate measurement of instrument noise (typically about 19 dB below
the measured signal level) was subtracted---in linear power units---from
the measured power level to remove the very minor effects of vector
signal analyzer self noise from the measurement. The attenuation of the
impedance matching pad, which was connected to the TV input but not to
the vector signal analyzer, was then subtracted (in dB) from the result
to determine the signal level that had been applied to the DTV receiver
antenna port. The presence of that pad at the TV input but not at the
spectrum analyzer input served a dual purpose---matching the respective
input impedances of the two devices and providing a 5.8 dB signal
advantage to the vector analyzer to minimize the impact of the vector
signal analyzer self noise.

Further details on the measurement procedure are contained in Appendix
A.

## Results {#results-1 .unnumbered}

The results of the minimum signal level measurements for the three
tested channels are shown in Figure 4‑1. Individual results for TV
channels 3, 10, and 30 are shown in Figures 4-2, 4-3, and 4-4,
respectively. The general format of the plots is as described in
Chapter 3 in the section titled, "Format of the Bar Graph Data", except
that, in the case of Figure 4-1, there are three bars per DTV
receiver---representing the three channels tested. Also, note the
differences in vertical scales among the four graphs.

### Nominal Performance and Variation Among Samples

Table 4-1 shows the statistical properties of the measurements of
minimum signal level at TOV.

[]{#__RefHeading___Toc118693183 .anchor}Table 4‑1. Statistics of Minimum
Signal Level at TOV

  ------------------------------------------ -------- --------- ---------
  **MINIMUM SIGNAL LEVEL AT TOV**            **Chan   **Chan    **Chan
                                             3**      10**      30**

  Median across all receivers (dBm)          -82.2    -83.2     -83.9

  Median re OET-69 planning factors          -1.2     -2.2      0.1

  Deviations of receivers from median (dB)                      

  \--Best performing receiver (dB)           -2.5     -1.7      -1.4

  \--Worst performing receiver (dB)          12.5     4.3       2.5

  \--89th percentile receiver (dB)           5.1      3.1       1.3

  Standard deviation (dB)                    3.7      1.6       0.9

  Total span from worst to best receiver     15.0     6.0       3.9
  (dB)                                                          
  ------------------------------------------ -------- --------- ---------

The median minimum signal level at TOV across all measured receivers was
found to decrease slightly with increasing channel number---with channel
3 requiring a 1.7‑dB higher signal than channel 30. The measured median
values match---within 1 dB---the -83 dBm minimum performance standard
recommended by the ATSC.[^281]

The median required signal levels were slightly better---by 1.2 dB and
2.2 dB, respectively---than that predicted for the VHF-low and VHF-high
bands using the OET-69 planning factors (-81.0 dBm) and closely matched
the predictions for channel 30 (-84.0 dBm).[^282] On channel 3, only 21
percent of the tested receivers performed more poorly in minimum signal
level than the performance modeled in OET-69 by an amount exceeding
1-dB---the approximate tolerance of the measurements.[^283] On channels
10 and 30, the numbers are 11 percent and 18 percent, respectively.

The variation among receivers was large on channel 3---with a 3.7‑dB
standard deviation. The two receivers exhibiting poorest performance
performed at levels 10.6 and 12.5 dB worse than the median. Those two
receivers---both the same brand---are responsible for much of the
observed variability; omitting them from the calculations reduces the
standard deviation to 2.3 dB. The third worst performer was 6.7 dB above
the median. 89 percent of the receivers (all but three) were within
5.1 dB of the median.

Variations were relatively small on channels 10 and 30. Standard
deviation across all receivers was 1.6 dB on channel 10 and 0.9 dB on
channel 30. The worst performers differed from the median by 4.3 and 2.5
dB, respectively, on channels 10 and 30, and 89 percent of the receivers
(all but three) were no more than 3.1 dB above (worse than) the median
on channel 10 and no more than 1.3 dB above (worse than) the median on
channel 30.

### Variations With TV Channel For One Sample

At least two TVs exhibited a much larger than expected variation in
reception performance---as measured by minimum signal level at
TOV---between the three tested TV channels. In order to further
characterize this variation, the receiver exhibiting the largest
variation between channels (receiver G2) was further tested to determine
minimum signal at TOV for each of the 12 VHF channels and for three UHF
channels. The results, shown in Figure 4‑5, indicate that the receiver
exhibits poor sensitivity throughout the low-VHF band (channels 2
through 6), but good sensitivity throughout the high-VHF band (channels
7 through 13) and the UHF band. On average, the high-VHF and UHF
performance is 13 dB better than the low-VHF performance. The reason for
this performance difference is not known.

The apparently abrupt change in sensitivity occurring between channels 6
and 7 is easier to understand if the data is plotted as a function of
frequency, as in Figure 4‑6. It can be seen that there is a large gap in
frequency between TV channels 6 and 7, and that the increase in minimum
signal at TOV that occurs in moving from the high-VHF band (channels
7-13) to the low-VHF band (channels 2-6) appears to actually begin, to a
small degree, in the lower portion of the high-VHF band. (Note that the
measured data is indicated by square symbols and measured points are
connected by straight lines.)

### Variation with Price and Type Category

#### Magnitude of Observed Variations With Product Type and Price {#magnitude-of-observed-variations-with-product-type-and-price-1 .unnumbered}

As can be seen in Table 4-2, the observed variations in minimum signal
level at TOV with product type and price categories were very small for
channels 10 and 30 (category medians differing from overall median by
less than 1 dB) and were somewhat larger for channel 3. On channel 3,
median performance of set-top boxes was 2.0 dB worse than the overall
median of all receivers and the best median performance was achieved by
the low-price DTV category, which slightly outperformed the medium and
high-priced categories. Most of the differences in median values between
categories are so small as to be considered insignificant, and even the
largest differences would influence reception performance only in
locations where the signal margin is very small.

[]{#__RefHeading___Toc118693184 .anchor}Table 4‑2. Product-Type/Price
Variations of Minimum Signal at TOV

  --------------------------------------------- -------- -------- --------
  **MINIMUM SIGNAL LEVEL AT TOV**               **Chan   **Chan   **Chan
                                                3**      10**     30**

  Median of Set-Top Boxes re Overall Median     2.0      0.5      0.7
  (dB)                                                            

  Median of Low-Price DTVs re Overall Median    -1.1     -0.2     -0.2
  (dB)                                                            

  Median of Medium-Price DTVs re Overall Median 0.0      0.5      0.0
  (dB)                                                            

  Median of High-Price DTVs re Overall Median   -0.7     -0.3     0.0
  (dB)                                                            
  --------------------------------------------- -------- -------- --------

#### Statistical Significance of Observed Variations With Product Type and Price {#statistical-significance-of-observed-variations-with-product-type-and-price-1 .unnumbered}

Table 4-3 shows the Pearson's correlation coefficient between the
minimum signal at TOV and the price of each DTV receiver. Random
sampling effects can lead to apparent correlations in a given collection
of DTV receivers even if the overall DTV population of receivers on the
market exhibits no such correlation; consequently, a statistical
assessment must be performed in order to judge whether the observed
correlation reflects an actual correlation in overall population or is
simply an artifact of sampling.

[]{#__RefHeading___Toc118693185 .anchor}Table 4‑3. Correlation
Coefficient of Minimum Signal at TOV with Price

  ----------------------------------------- --------- ---------- ----------
  **Pearson's Correlation Coefficient of    **Chan    **Chan     **Chan
  Minimum Signal at TOV with Price**        3**       10**       30**

  All Tested Receivers                      -14.3%    -4.9%      +3.9%

  DTVs Only (no Set-Top Boxes)              -0.3%     +0.4%      +12.3%
  ----------------------------------------- --------- ---------- ----------

Chapter 3 explains the methods and pitfalls of such a statistical
assessment. Using typical assumptions, one would conclude that an
observed correlation coefficient with a magnitude of 32 percent or
higher is unlikely to occur (less than five percent probability) in a
sample size of 28 (the total number of receivers tested for this report)
if there is no correlation in the overall population. Similarly, with a
sample size of 23 (the number of DTVs---excluding set-top boxes---tested
for this report), a correlation coefficient magnitude of 35 percent or
higher is unlikely to occur if there is no correlation in the overall
population. Thus, we would conclude that an observed correlation is
statistically significant only if its magnitude exceeds the appropriate
one of these thresholds.[^284]

None of the price/performance correlations found here come even close to
the threshold for statistical significance. Thus, the measurements of
minimum signal at TOV show no statistically significant correlation of
performance with price.

![](media/image2.wmf){width="6.497916666666667in"
height="4.254166666666666in"}

[]{#__RefHeading___Toc119201838 .anchor}Figure 4‑1. Measured Minimum
Signal Level at TOV on Three Channels

![](media/image6.wmf){width="6.497916666666667in"
height="4.267361111111111in"}

[]{#__RefHeading___Toc119201839 .anchor}Figure 4‑2. Measured Minimum
Signal Level at TOV on Channel 3 (Low VHF)

![](media/image7.wmf){width="6.497916666666667in"
height="4.2868055555555555in"}

[]{#__RefHeading___Toc119201840 .anchor}Figure 4‑3. Measured Minimum
Signal Level at TOV on Channel 10 (High VHF)

![](media/image8.wmf){width="6.497916666666667in"
height="4.2868055555555555in"}

[]{#__RefHeading___Toc119201841 .anchor}Figure 4‑4. Measured Minimum
Signal Level at TOV on Channel 30 (UHF)

![](media/image9.wmf){width="6.497916666666667in"
height="4.222222222222222in"}

[]{#__RefHeading___Toc119201842 .anchor}Figure 4‑5. Measured Minimum
Signal Level at TOV Versus Channel for Receiver G2

![](media/image10.wmf){width="6.497916666666667in"
height="4.222222222222222in"}

[]{#__RefHeading___Toc119201843 .anchor}Figure 4‑6. Measured Minimum
Signal Level at TOV Versus Frequency for Receiver G2

# ** ****INFERRED NOISE FIGURE** {#inferred-noise-figure .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

The minimum signal level at TOV, presented in Chapter 4, can be viewed
as the combined effect of two properties of the DTV receiver: the
internal noise created by the receiver's input circuitry and the CNR
required to produce a clean picture. Separating the measurement into
those two basic terms provides a better understanding of the differences
in performance between DTV receivers. It should be noted that this
breakout is strictly valid only when reception sensitivity is limited by
the receiver's amplifier noise, which we anticipate to be true for most
receivers; however, if other factors limit reception sensitivity, the
"inferred" receiver noise calculations in this chapter reflect those
other performance limitations rather than actual receiver noise.[^285]

The internal noise created by a receiver is often expressed in terms of
noise figure. The noise figure of a receiver is the effective amount of
noise created by the input circuitry of the receiver, measured relative
to a physical limit on noise known as thermal noise and referenced to
the input of the receiver. While noise figure cannot be directly
measured externally, the effective noise figure can be inferred from the
required CNR measurements of Chapter 3 in conjunction with the minimum
signal level at TOV, as measured in Chapter 4.

Figure 5-1(a) illustrates measurement of required CNR (i.e., white noise
threshold). The vertical line represents a range of signal and noise
amplitudes that could be applied to the antenna terminal of a TV
receiver. With external white noise added at a level well above the
internal noise of the receiver, signal levels in the lower, red portion
of the line will result in no TV picture. Signals in the yellow range
will produce a picture degraded by demodulation errors. Signals in the
green range, with signal level exceeding the noise level by an amount
greater than the required CNR, will produce a picture free of
reception-related defects. (The carrier-to-noise [ratio]{.underline}
(CNR), becomes a difference rather than a ratio, because of the
logarithmic scaling implied by measurements in decibels.)

Figure 5-1(b) illustrates measurement of minimum signal at TOV, the
minimum signal level required to achieve a clear picture absent any
external noise. Assuming that the TV reception is limited by the
receiver's broadband internal noise, this minimum signal level can be
viewed as the sum (in dB) of two parameters---the internally generated
noise level of the DTV receiver and the amount by which the signal must
exceed that noise level, i.e., the required CNR. The noise level of the
receiver can be expressed as the sum (in dB) of the noise figure of the
receiver and the thermal noise at some reference temperature. Thus, we
have

*Minimum Signal at TOV (dBm) = Thermal Noise (dBm) + Noise Figure (dB) +
Required CNR (dB)*

Thermal noise is a function only of reference temperature and
measurement bandwidth and is given by

*Thermal Noise (dBm) = 10 log(k T B) + 10 log(1000 mW/W)*

where

*k = Boltzmann's constant = 1.38065 x 10^-23^ joules/°K*

*T = reference temperature in degrees Kelvin (290°K for this
report)*[^286]

*B = the measurement bandwidth = 6,000,000 Hz for a television channel*

*10 log(1000 mW/W) provides the conversion from dBWatts to dBmilliwatts*

Using the above values, thermal noise = -106.2 dBm.

If the noise generated internally by the DTV receiver is similar to
white Gaussian noise, then the required CNR in Figure 5-1(a) is the same
as that in Figure 5-1(b); consequently, noise figure of the receiver can
be computed as\
\
*Noise Figure (dB) = Minimum Signal at TOV (dBm) -- Required CNR (dB) --
Thermal Noise (dBm)*

## Results {#results-2 .unnumbered}

The noise figures for all tested receivers on the three tested channels
have been computed as above and are shown in Figure 5-2. Individual
results for TV channels 3, 10, and 30 are shown in Figures 5-3, 5-4, and
5-5, respectively. The general format of the plots is as described in
Chapter 3 in the section titled, "Format of the Bar Graph Data", except
that, in the case of Figure 5-2, there are three bars per DTV
receiver---representing the three channels tested. The reader should
note the differences in vertical scales among the four graphs.

Note that in performing the noise figure calculation, the required CNR
is assumed to be constant across the TV channels for the reasons
discussed in the "Effect of TV Channel" section of Chapter 3. Thus, the
CNR measurements on channel 30 are applied to channels 3 and 10, as
well.

### Nominal Noise Figure and Variation Among Samples

Table 5-1 shows the statistical properties of the noise figure across
all tested receivers.

[]{#__RefHeading___Toc118693186 .anchor}Table 5‑1. Statistics of
Receiver Noise Figure

  --------------------------------------------- -------- -------- --------
  **NOISE FIGURE**                              **Chan   **Chan   **Chan
                                                3**      10**     30**

  Median across all receivers (dB)              8.8      7.6      6.9

  Median re OET-69 planning factors             -1.2     -2.4     -0.1

  Deviations of receivers from median                             

  \--Best performing receiver (dB)              -2.5     -1.3     -1.3

  \--Worst performing receiver (dB)             12.2     4.5      2.6

  \--89^th^ percentile receiver (dB)            4.5      3.3      1.2

  Standard deviation (dB)                       3.6      1.6      0.9

  Total span from worst to best receiver (dB)   14.7     5.7      3.9
  --------------------------------------------- -------- -------- --------

The median noise figure across all measured receivers was found to
decrease with channel---with the noise on channel 30 being 1.9 dB lower
than that on channel 3. The median noise figures were 1.2 to 2.4 dB
better than those shown in the OET-69 planning factors for the VHF bands
(10 dB) and essentially matched the planning factor for the UHF band
(7 dB).

On channel 3, only 21 percent of the tested receivers performed more
poorly in noise figure than the value modeled in OET-69 by an amount
exceeding 1-dB---the approximate tolerance of the measurements.[^287] On
channels 10 and 30, the numbers are 7 percent and 18 percent,
respectively.

The variations among receivers were large on channel 3---with a 3.6 dB
standard deviation and two receivers performing at levels 10.3 and
12.2 dB worse than the median. More attention to tuner design for those
two receivers might significantly improve performance in weak signal
conditions. 89 percent of the receivers (all but three) were no more
than 4.5 dB above (worse than) the median noise figure.

Variations were relatively small on channels 10 and 30. Standard
deviation across all receivers was 1.6 dB on channel 10 and 0.9 dB on
channel 30. The worst performers differed from the median by 4.5 and 2.6
dB, respectively, on channels 10 and 30, and 89 percent of the receivers
(all but three) were no more than 3.3 dB above (worse than) the median
noise figure on channel 10 and no more than 1.2 dB above the median
noise figure on channel 30.

### Variation With Product Type and Price

#### Magnitude of Observed Variations With Product Type and Price {#magnitude-of-observed-variations-with-product-type-and-price-2 .unnumbered}

As can be seen in Table 5-2, the observed variations in receiver noise
figure with product type and price categories were very small (category
medians differing from overall median by less than 1 dB) for channels 10
and 30 and were somewhat larger for channel 3. On channel 3, median
noise figure of set-top boxes was 1.7 dB worse than the overall median
of all receivers. The best median noise figure---1.4 dB better than the
overall median---occurred in the low-price DTV category. Such
differences are likely to influence performance only in locations where
the signal margin is very small.

[]{#__RefHeading___Toc118693187 .anchor}Table 5‑2. Product-Type/Price
Variations of Receiver Noise Figure

  ----------------------------------------------- -------- -------- --------
  **NOISE FIGURE**                                **Chan   **Chan   **Chan
                                                  3**      10**     30**

  Median of Set-Top Boxes re Overall Median (dB)  1.7      0.1      0.6

  Median of Low-Price DTVs re Overall Median (dB) -1.4     -0.1     0.0

  Median of Medium-Price DTVs re Overall Median   0.0      0.4      -0.1
  (dB)                                                              

  Median of High-Price DTVs re Overall Median     -0.8     -0.3     0.0
  (dB)                                                              
  ----------------------------------------------- -------- -------- --------

#### Statistical Significance of Observed Variations With Product Type and Price {#statistical-significance-of-observed-variations-with-product-type-and-price-2 .unnumbered}

Table 5-3 shows the Pearson's correlation coefficient between the noise
figure and the price of each DTV receiver. Given the similarity of
results with those for minimum signal at TOV, the reader is referred to
Chapter 4 for a discussion of the interpretation of these results. The
bottom line is that there is no statistically significant correlation of
noise figure with price of the receivers..

[]{#__RefHeading___Toc118693188 .anchor}Table 5‑3. Correlation
Coefficient of Receiver Noise Figure with Price

  ----------------------------------------- -------- ---------- ----------
  **Pearson's Correlation Coefficient of    **Chan   **Chan     **Chan
  Noise Figure with Price**                 3**      10**       30**

  All Tested Receivers                      -14%     -4%        +6%

  DTVs Only (no Set-Top Boxes)              -1%      -1%        +11%
  ----------------------------------------- -------- ---------- ----------

### Relative Variations in Noise Figure and Required CNR

Figure 5-6 shows the required CNR for each receiver as a function of
noise figure on each of the three tested channels. Contour lines can be
used to read the combined effect of the two parameters on minimum signal
at TOV. It is clear from the plot that most of the variation in receive
sensitivity (i.e., minimum signal level at TOV) of the DTV receivers is
due to variations in receiver noise figures rather than variations in
the CNR required by the demodulator. In fact, based on standard
deviations of the parameters, variability in noise figure among the
receivers is 4.2 times as high as the variability in required CNR on
channel 30, where the noise figure variations are smallest. On channels
10 and 3, respectively, the noise figure shows 7 and 16 times the
variability of required CNR.

![](media/image11.wmf){width="2.410416666666667in"
height="3.803472222222222in"}
![](media/image12.wmf){width="2.0284722222222222in"
height="3.797222222222222in"}

\(a\) Required CNR (b) Minimum Signal at TOV

[]{#__RefHeading___Toc119201844 .anchor}Figure 5‑1. Relationship between
Minimum Signal at TOV and Required CNR

![](media/image13.wmf){width="6.497916666666667in"
height="4.293055555555555in"}

[]{#__RefHeading___Toc119201845 .anchor}Figure 5‑2. Noise Figure on
Three Channels

![](media/image14.wmf){width="6.497916666666667in"
height="4.2868055555555555in"}

[]{#__RefHeading___Toc119201846 .anchor}Figure 5‑3. Noise Figure on
Channel 3 (Low VHF)

![](media/image15.wmf){width="6.497916666666667in"
height="4.2347222222222225in"}

[]{#__RefHeading___Toc119201847 .anchor}Figure 5‑4. Noise Figure on
Channel 10 (High VHF)

![](media/image16.wmf){width="6.497916666666667in"
height="4.228472222222222in"}

[]{#__RefHeading___Toc119201848 .anchor}Figure 5‑5. Noise Figure on
Channel 30 (UHF)

[]{#__RefHeading___Toc119201849
.anchor}![](media/image17.wmf){width="6.497916666666667in"
height="4.2347222222222225in"}Figure 5‑6. Required CNR Versus Noise
Figure

# ** ****PERFORMANCE AGAINST MULTIPATH USING FIELD CAPTURES** {#performance-against-multipath-using-field-captures .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

Chapters 3 through 5 dealt with over-the-air reception performance of
the DTV receivers with a signal that is [un]{.underline}impaired by
multipath. Chapter 6 addresses the issue of multipath by determining the
ability of each receiver to process broadcast DTV signals that were
received and recorded on actual television antennas at various locations
in New York City and Washington, DC.

The selected digital RF recordings, also called "captures" or "field
ensembles", were 47 of the 50 captures recommended by the ATSC for DTV
receiver testing.[^288] ATSC's characterization of the 50 captures is
worth noting.

> *"Most of the field ensembles contain data captured at sites where
> reception was difficult. The field ensembles are clearly not meant to
> represent the statistics of overall reception conditions but rather to
> serve as examples of difficulties that are commonly experienced in the
> field."*[^289]

Three of the 50-recommended captures were excluded from testing with the
consumer DTV receivers because they contain no video content and
therefore require specially instrumented receivers for testing; however,
extrapolation of instrumented receiver test results for those three
captures to the consumer receivers is discussed later in this chapter.
The remaining 47 captures break down as follows:

1.  sites characterized as urban (19), suburban (12), rural (2), and
    various other categories that overlap these designations (14);

2.  single-family homes (18), townhouses (8), and apartments (21);

3.  indoor antennas (39) and outdoor log-periodic antennas (8)

Each of the captures was recorded in the year 2000 by the Advanced
Television Test Center (ATTC) or the Association for Maximum Service
Television (MSTV) using specialized digital capture equipment. Each
capture has duration of either 23 or 25 seconds. An RF player allows the
recorded signal to be translated to any standard TV broadcast channel
and played back as a repeating loop.

Appendix B lists the captures and summarizes some of the test results.

## Measurement Method {#measurement-method-2 .unnumbered}

The test configuration was essentially the same as that described in
Chapter 3, for the white-noise threshold measurements, except that no
noise was injected. The nine-way splitter allowed the signal to be
simultaneously applied to as many as eight DTV receivers and a vector
signal analyzer. All 47 selected RF captures were played through each
group of receivers. Performance is reported in this chapter as the
number of captures successfully played by a receiver for two different
criteria of success. As a consistency check, receiver D3 was included in
each group of eight receivers that were tested; the numbers of captures
played successfully on receiver D3 on the various tests were consistent
within one count.

Signal attenuators were adjusted to provide a nominal input of -30 dBm
at the receiver antenna ports. The attenuator was not separately
adjusted for each capture file; consequently, the actual injected level
within the channel bandwidth of 6 MHz varied from -38 to -28 dBm based
on the level recorded in each capture. All but four of the captures
played at an in-channel level within 2 dB of the nominal.

Successful playback of a capture was defined in terms of the number of
video error bursts observed during a single playback loop after the loop
had played at least three times. (In many cases the performance was
monitored over several loops and, if the results varied, a median value
was chosen.) A video error burst lasting more than one second was
counted based on the approximate duration in seconds. Thus, an error
burst lasting three seconds was counted as three errors. Errors
occurring during or immediately after the loop-restart time were not
counted, nor were errors associated with known defects (dropped symbols)
in eight of the captures, as documented by the ATSC.[^290]

The testing was performed on channel 30. It should be noted that with
many of the DTV receivers, simply tuning to channel 30 was not
sufficient to ensure successful acquisition of the TV signal---even with
one of the easier captures. The original source material for the
captures was recorded from eight different DTV broadcast stations in two
cities. Because of the facts that multiple programs can be broadcast on
a single channel and that most DTV channels are associated with an
equivalent analog channel number that is used in selecting the station
(PSIP requirements),[^291] many of the receivers were "confused" by
changing broadcast stations from playback of one capture to playback of
the next, even though the RF channel remained constant. As a result,
various methods such as rescanning the channels were necessary to get
many of the receivers to operate after changing between captures that
originated on different TV channels. To save time in the process, the
captures were sorted by originating broadcast station before testing,
and were further sorted to allow the more benign captures from a given
broadcast station to be played first, in order to lock the receivers
onto each new broadcast station.

Further details on the measurement procedure are contained in Appendix
A.

## Results {#results-3 .unnumbered}

Figure 6-1 shows the results of testing each DTV receiver with each of
the 47 RF captures. The general format of the plot is as described in
Chapter 3 in the section titled, "Format of the Bar Graph Data", but
with a few differences. The blue (lower) portion of each bar represents
the number of captures that played without a visible error during a
single loop of the capture. The upper portion of each bar adds the
captures that played with no more than two visible errors during a
single loop of capture.

It should be noted that, unlike the plots presented in earlier chapters
of this report, increased performance in this plot is represented by
taller bars. Also, in addition to the four category groupings of DTV
receivers, Figure 6‑1 includes an additional bar on the right, labeled
2000REF. This receiver was retained from field testing in the year 2000
and was included in the RF capture testing presented here. Further
discussion of this receiver is provided later in this chapter as well as
in Chapter 7.

### Nominal Performance and Variation Among Samples

Unlike the results of other testing presented in this report, the
results of testing against the RF captures are heavily clustered into
two major performance tiers. The upper-tier (better) performers
successfully played about 29 captures without error and about 37
captures with two or fewer errors. The lower-tier performers
successfully played about 7 captures without error and about 9 with two
or fewer errors. Neglecting receivers D1 and L2, all results fall within
±2 captures of one of these nominal results, as shown in Table 6‑1.
Receivers D1 and, perhaps, L2, appear to represent an additional
performance tier slightly above the lower tier; this tier will be
designated as "lower tier+".[^292]

The upper-tier performers represent a quantum leap in ability to handle
the most difficult multipath conditions. The receivers that tested in
this tier are known to include the latest generation of demodulator
chips from at least two of the major DTV chip developers.

[]{#__RefHeading___Toc118693189 .anchor}Table 6‑1. Number of Captures
Successfully Played By Each Performance Tier

  ------------- ----------- -------------------- -------------------------
                Number of   Number of Captures   Number of Captures Played
                Consumer    Played with No       with No More Than 2
                Receivers   Errors               Errors

  Lower Tier    16          7 ±2                 9 +2/-1

  Lower Tier+   2           8 and 12             14 and 16

  Upper Tier    10          29 ±2                37 ±2
  ------------- ----------- -------------------- -------------------------

It should be noted that some of the RF captures may contain recording
flaws---other than the dropped symbols discussed earlier---that could
prevent error-free demodulation regardless of how advanced the
demodulator technology may be. For example, four of the captures for
which no tested receiver achieved demodulation free of visual errors
were identified by the ATSC as having possible non-linearities caused by
high-level adjacent channels overdriving the recording system. These or
other potential flaws may preclude a 100% success rate on the 47
captures from ever being achieved by any demodulator; consequently, we
view the multipath-performance data based on these captures to be useful
for purposes of comparing receivers, but not as an absolute measure of
performance.

### Extrapolation to the Three Captures Lacking Video Content

Three of the ATSC-recommended RF captures lacked video content and could
not, therefore, be tested with the consumer DTV receivers; however, they
were tested with a five-year-old instrumented DTV receiver, labeled
"2000REF" in Figure 6‑1. That receiver provides visual and audible
indications when segment errors[^293] occur during demodulation of the
DTV signal.

Tests were performed first using three captures [with]{.underline} video
content (labeled as numbers 27, 29, and 45 in Appendix B). These
captures exhibited 4, 1, and 2 visual errors, respectively, with the
2000REF receiver. Results showed a one-to-one correspondence of segment
error bursts with observed video error bursts for these captures.[^294]

Tests of the 2000REF receiver with the captures having no video content
(labeled 22, 24, and 44 in Appendix B) showed no segment errors. The
absence of segment errors indicates that the 2000REF receiver would have
exhibited no visible errors on these captures had there been video
content to observe. Given that this five-year-old receiver---now
obsolete by two demodulator generations---is among the worst performing
of the tested receivers in terms of multipath performance (per
Figure 6‑1), it is considered likely that all of the tested consumer
receivers would have exhibited no visual errors for these three captures
had there been video content to observe. Consequently, if one wanted to
extrapolate performance against the entire set of 50 ATSC-recommended RF
captures from the tests of the 47 with video content, it is likely that
three zero-error successes should be added to the results for each
receiver.

### Variation With Product Type and Price

Interestingly, both upper-tier and lower-tier performers appear in all
three price categories of DTVs. This suggests that performance is not a
function of price---at least in the DTV category.

On the other hand, none of the set-top boxes---the least expensive way
to receive a digital broadcast if you connect it to an existing
television---perform at the upper tier level.

Some understanding of these results can be achieved by looking at the
introduction date of each tested receiver to the U.S. market.
Introduction dates (by month and year) for 25 of the 28 receivers tested
for this report were provided by the manufacturers; the remaining three
were determined by a web search. Though introduction dates are not
reported here in order to avoid possible date-based linking of
individual product models with the receiver designations used in this
report, the following observations are relevant.

1.  All ten upper-tier performers were introduced in or
    [after]{.underline} March, 2005.

2.  The set-top boxes---all of which performed at the lower tier or
    "lower tier+"---were introduced in or [before]{.underline} November,
    2004.

3.  Of the lower-tier or lower-tier+ integrated DTVs (i.e., excluding
    set-top boxes), two were released in the latter part of 2004 and the
    remaining eleven were introduced between March and July, 2005.

Since the set-top box models available on the market at the time of the
reported tests were 2004 or earlier models,[^295] their lower-tier or
"lower-tier+" performance reflects the lack of availability of the newer
generation of DTV demodulator chips at the time of product design.

Among the DTVs, it is clear that introduction dates in or after March
2005 are consistent with feasibility of including of the newer
technology. Among the tested DTVs that were introduced in or after March
2005, 48 percent performed at the upper tier level. It is probable that
some of the products introduced in this time frame carried over
tuner/demodulator designs from a previous generation.

One would expect that, as future models are released, the newer
generation demodulator technology will migrate to an increasing extent
into all DTV product categories, including set-top boxes, and that, at
some point in the near future, the improved technology will be contained
in all newly introduced receivers. In the meantime, there is little
publicly available information to assist those consumers who live in
locations characterized by challenging multipath conditions in selecting
DTV receivers that achieve the upper tier of performance.

### Relationship Between Multipath Performance and White Noise Threshold

There is some reason to expect that improvements in multipath
performance---which is achieved in part by increasing the number of taps
in the demodulator's equalizer circuit---might come at the expense of
poorer white noise threshold, because, even in the absence of multipath,
the additional taps could be expected to add noise that is related to
carrier amplitude. (Since an automatic gain control would be expected to
provide sufficient gain to amplify the input signal---whatever its
level---to a fixed level for processing by the demodulator, one would
expect that the tap noise generated after this variable amplification
would be at a fixed level relative to the DTV signal rather than at a
fixed level relative to the antenna input---hence the impact would
appear as a degradation to required CNR \[white noise threshold\] rather
than an increase in noise figure.)

Figure 6-2, shows the measurements of white noise threshold (from
Chapter 3) plotted against multipath performance as measured by the
number of RF captures (out of 47) that were successfully played without
error. The lower tier of multipath performers (presumably containing
earlier generation 8‑VSB decoders) had a median CNR threshold of 15.3
dB,[^296] which is slightly worse than the 15.19 dB threshold achieved
by the ACATS Grand Alliance prototype receiver.[^297] Until the most
recent VSB decoder generation came to market, the trend of the earlier
VSB decoder improvements was a very slight worsening of the CNR at
threshold as a tradeoff for improved multipath performance. The 15.1 dB
median CNR threshold for the upper tier of multipath performers suggests
that this trend is over. In fact, the seven best-performing receivers in
terms of white noise threshold are in the upper tier of multipath
performance.

![](media/image3.wmf){width="6.497916666666667in"
height="4.247916666666667in"}

[]{#__RefHeading___Toc119201850 .anchor}Figure 6‑1. Performance Against
47 RF Captures

![](media/image4.wmf){width="6.497916666666667in"
height="4.209027777777778in"}

[]{#__RefHeading___Toc119201851 .anchor}Figure 6‑2. White Noise
Threshold Versus Multipath Performance

# ** ****INFERRED PERFORMANCE AGAINST REPRESENTATIVE MULTIPATH CONDITIONS** {#inferred-performance-against-representative-multipath-conditions .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

The measurements presented in the previous chapter show that DTV
receivers on the market at the time of these tests differ markedly in
their ability to handle certain difficult multipath conditions. In order
to understand the impact of these differences, one would also like to
know how prevalent are the types of multipath conditions that
differentiate receiver performance. If those conditions occur only
rarely, then the performance differences will not be of consequence to
most consumers; on the other hand, if they occur frequently, then the
performance differences between "upper tier" and "lower tier" performers
will radically affect many consumers.

Although an investigation of the frequency of occurrence of various
multipath conditions is beyond the scope of this report, some of the
measured data presented in Chapter 6 can be combined with results from a
year-2000 FCC field investigation to provide at least a partial answer.

## Multipath Capability Based on Year-2000 Field Tests {#multipath-capability-based-on-year-2000-field-tests .unnumbered}

In 2001, the FCC Laboratory reported the results of year-2000 field
tests of DTV coverage in Washington, DC and of DTV receiver
performance.[^298] In that study, the performance of six DTV receivers
was evaluated at 60 locations for reception of two broadcast UHF DTV
stations (channels 34 and 48). Nine of the locations were specifically
selected for high-multipath conditions; however, 51 locations---referred
to as "coverage sites", were selected in ways that can be expected to
yield more representative results. It is these 51 sites that are of
interest for the current analysis.

Of the 51 coverage sites, 38 were located at five-mile intervals along
radials from the broadcast antenna of digital channel 48 in Washington,
DC. The other 13 coverage sites were chosen from sites randomly selected
from within a box 17.5 miles on a side, centered on the same broadcast
antenna.[^299]

At each site, reception performance measurements were made using at
least two antenna systems:

1.  a log-periodic, outdoor-type antenna on a 30-ft. mast, and

2.  one of two indoor-type antennas on a 7-ft. tripod located outdoors.

The tripod-mounted antenna measurements were intended to indicate
reception performance that could be expected with an antenna located
indoors to the extent that could easily be determined given that access
to homes or other buildings at randomly selected sites is not generally
available. Though the antenna was not located indoors, the height and
antenna type were consistent with indoor use. In general, a bow tie
antenna was used as the "indoor-type" antenna. If the bow tie failed to
achieve reception, a small, indoor, UHF log-periodic antenna ("Silver
Sensor") was tried.

The tests included six DTV receivers, one of which was an instrumented
prototype receiver to be used as a reference. Initially, the reference
receiver was a [second]{.underline}-generation Zenith ProDemodulator.
After two thirds of the testing was complete (on July 17, 2000), that
receiver was replaced with a [third]{.underline}-generation Zenith
ProDemodulator. The third generation included an equalizer with longer
ghost cancellation times and slightly improved pre-ghost performance at
the expense of slightly degraded white noise performance, relative to
the second generation.

That same third-generation receiver was tested this year, along with the
28 current-generation consumer receivers, to determine performance
against the 47 RF captures, as described in Chapter 6. The result for
the third generation reference receiver is shown as the right-most bar
(labeled "2000REF") of Figure 6-1. In the current tests, that
receiver---with equalizer technology now two generations behind the
latest technology---tied for either the worst or second worst
performance (depending on whether counting the zero-error data or the
two-error data) when included with the current crop of receivers that
were tested. Given that the third generation was used for only one third
of the year-2000 tests and that a second generation receiver---with
inferior equalizer technology---was used for two thirds of those tests,
one can assume that the reported field test results for the "reference
receiver" from those earlier tests correspond to receiver with multipath
performance at or below the level shown by the "2000REF" bar in
Figure 6‑1.

In the year-2000 tests, all but one of the 51 sites exhibited field
strengths judged to be large enough for theoretical DTV reception.[^300]
Using the mast-mounted, outdoor-type antenna, the reference receiver
received channel 34 with no visible picture errors in all 50 of those
sites and received channel 48 without visible errors in 49 of the 50
sites. Thus, the reference receiver successfully handled multipath
conditions in 99 percent of the test-site/broadcast-station combinations
with the mast-mounted antenna. When using the tripod-mounted indoor-type
antennas (including the Silver Sensor, when needed), the reference
receiver handled 85 percent of the test-site/broadcast-station
combinations without visible picture errors.

Thus, receivers performing at or below the level of the 2000REF receiver
shown in Figure 6‑1 were able to successfully handle 99 percent of the
multipath situations in the "coverage tests" when using a mast-mounted
outdoor antenna. Though the tests involved only one metropolitan area
and the sample size was too small to consider these numbers
statistically accurate, the sites selected are expected to be far more
representative of randomly selected real world conditions than the
ATSC-recommended sites, which were chosen because of their difficult
multipath conditions. Given that the 2000REF results show performance at
or below almost all of the lower-tier performers in the Figure 6-1, one
can reasonably assume that, even lower-tier multipath performance (as
defined in Chapter 6) is adequate to handle the vast majority of
reception conditions (at least in the Washington, DC area) when the
receiver is paired with a good outdoor, mast-mounted antenna.

Similarly, receivers performing at or below the level of the 2000REF
receiver shown in Figure 6‑1 were able to successfully handle 85 percent
of the multipath situations in the "coverage tests" when using a
indoor-type antenna at a 7-foot height (but located outdoors). It
appears likely, then, that multipath performance at the lower tier of
Figure 6-1 may be adequate for most locations in conjunction with an
indoor antenna, but that improved multipath performance (e.g., the upper
tier of Figure 6‑1) might offer benefits in many locations.

## Impact of Representative Multipath on Required CNR {#impact-of-representative-multipath-on-required-cnr .unnumbered}

The year-2000 field tests also offer some insight into the impact of
multipath on required CNR for a receiver.

Those tests included measurements of required CNR at each site. The
required CNR was determined by adding white Gaussian noise to an
amplified version of the signal received from the antenna and adjusting
the noise level until the threshold of visibility (TOV) was observed.

Though the precision of the measurements was limited by the use of
one-dB steps in adjusting the noise level, the median required CNR
across all of the coverage sites provides an indication of the required
CNR in real world multipath conditions. In general it was found that the
newer generation receivers performed better---i.e., had a lower required
CNR---that older generation receivers. When used with the mast-mounted
antenna, the newest generation receiver that was used throughout the
test period for the 2001 report (a "third generation" receiver
identified as receiver 5 in that report) exhibited a median required CNR
of 15.9 dB across all "coverage sites" tested for one of the received
broadcast stations and 16.0 dB for the other. With the tripod-mounted
antennas, the corresponding numbers were 17.0 and 16.6 dB.

Absent better information, a required CNR of 16.0 dB may be a reasonable
estimate of reception performance in typical multipath conditions if an
outdoor antenna is used.

# ** ****SUMMARY AND CONCLUSIONS** {#summary-and-conclusions .Style-Heading-1H1-+-Before:--12-pt-After:--18-pt}

The laboratory-based measurements performed for this report emulated two
types of over-the-air reception conditions for DTV receivers:

> \(1\) Unimpaired signal (i.e., no multipath) \[Chapters 3 -- 5\], and
>
> \(2\) Signal impaired by multipath (ghosts) \[Chapter 6\]---focussing
> on particularly difficult multipath conditions.

The unimpaired signal measurements can be used to quantitatively predict
receiver performance under benign reception conditions---i.e., with
little multipath. The multipath tests provide a basis for comparing the
ability of different DTV receivers to handle difficult multipath
conditions---without directly addressing the frequency of occurrence of
those multipath conditions.

The linkage developed in Chapter 7 between the new, laboratory-based
measurements performed for this report and earlier FCC field-test data
provides a basis for anchoring the multipath results to representative,
real-world reception conditions.

The purpose of this report has been to provide an empirical basis for
answering three questions that derive from study requirements imposed by
Congress as part of SHVERA \[Chapter 1\]. Those questions are as
follows.

> \(1\) Is there is a wide variation in the ability of reasonably-priced
> consumer digital television sets to receive over-the-air signals, such
> that at a given signal strength some may be able to display
> high-quality pictures while others cannot?
>
> \(2\) Is such variation related to the price of the television set?
>
> \(3\) Should such variation be factored into setting a standard for
> determining whether a household is unserved by an adequate digital
> signal?

In addressing these questions, separate answers will be provided for
benign signal conditions (little multipath) and difficult multipath
conditions. The third question will be addressed by comparing measured
results to the receiver performance planning factors in OET-69.

The benign signal case will be evaluated in terms of the measured values
of minimum signal at the threshold of visibility of errors (TOV) for the
receivers. This specifies the ability of a DTV receiver to operate with
a weak signal---absent significant multipath or interference. To provide
a better understanding of differences among receivers, the discussion
will also delve into two receiver parameters that combine to determine
the minimum signal at TOV. These are:

1.  the white noise threshold (required carrier-to-noise ratio \[CNR\]);
    and

2.  the effective noise figure of the receiver.

The first of these characteristics is a demodulator characteristic that
is independent of which TV channel contains the signal of interest. The
second is a measure of the internally generated electronic noise of the
receiver; it [does]{.underline} vary with TV channel. In reporting
channel-dependent data, results are presented for the low-VHF, high-VHF,
and UHF bands, which were represented in the measurements by TV channels
3, 10, and 30.

## Variation in Reception Performance {#variation-in-reception-performance .unnumbered}

### For Benign Signal Conditions

In the low-VHF band, the variation in reception performance among the
tested DTV receivers was moderately high. The minimum signal level at
TOV exhibited a 3.7‑dB standard deviation among the receivers. 89
percent of the receivers exhibited performance within 5.1 dB of the
median performance, but two (seven percent) same-brand receivers were
significantly worse than the median---by 10.6 and 12.5 dB. Omitting
those two receivers from the data set would reduce the standard
deviation to 2.3 dB.

In the high-VHF and the UHF bands, the variation in reception
performance among the tested receivers was small. In the high-VHF band,
the minimum signal level at TOV exhibited a 1.6‑dB standard deviation;
89 percent of the receivers exhibited performance within 3.1 dB of the
median, and the poorest performing receiver exhibited a performance
level 4.3 dB worse than the median. In the UHF band, the minimum signal
level at TOV exhibited a 0.9‑dB standard deviation; 89 percent of the
receivers exhibited performance no worse than 1.3 dB poorer than the
median, and the poorest performing receiver exhibited a performance
level 2.5 dB worse than the median.

Most of the variation in reception performance among the tested
receivers was due to differences in receiver noise figure rather than in
required CNR. The noise figure variations were larger than the
required-CNR variations by factors ranging from 4.2, in the UHF band, to
16, in the low-VHF band.

### For Difficult Multipath Conditions

Independent of band, there was a wide variation in ability of the
receivers to handle difficult multipath conditions; however, linkage of
the current results with earlier field test results suggest that the
observed performance differences are of no consequence in the vast
majority of reception locations, if an outdoor, mast-mounted antenna is
used. When an indoor antenna is used, the linkage suggests that the
observed performance differences would be significant in many, but
probably not most, locations.

In tests against RF captures recorded from antennas at sites
specifically selected for their challenging multipath conditions, the
multipath-handling capability of the receivers fell primarily into two
tiers of performance. The upper (better-performing) tier included ten
receivers. The lower tier included 16 receivers. Two receivers fell in
between the two tiers, but closer to the lower tier. The upper-tier
receivers were able to handle about four times as many of the RF
captures as the lower tier.

The FCC's year-2000 field tests at 51 sites that were selected without
regard to multipath---and thus more likely to be representative of the
typical range of common reception conditions than the RF captures---can
be used to put the current multipath test results in perspective. A
now-obsolete instrumented receiver left over from those earlier field
tests was retested this year against the RF captures and was found to
perform at the bottom of the lower performance tier. But, in the year
2000 field tests that now-inferior receiver successfully handled
multipath in 99% of the combinations of site and broadcast
station,[^301] when a mast-mounted outdoor antenna was used. The success
rate dropped to 85 percent when an indoor-type antenna was used,[^302]
indicating an increased likelihood that better multipath performance in
the receiver would have helped.

## Price-Dependence of Reception Performance {#price-dependence-of-reception-performance .unnumbered}

### For Benign Multipath Conditions

In assessing the price-dependence of receiver performance, one must
consider two things:

\(1\) whether an observed variation of performance with price among the
tested receivers is statistically significant---i.e., whether it
represents a real trend among DTV receivers currently on the market or
whether it is a statistical artifact of the particular selection of
receivers that were tested; and,

\(2\) whether an observed variation of performance with price is of
sufficient magnitude to significantly affect television performance.

In the low-VHF band, though the variability in performance among the
receivers was moderately high, the variability among the price
categories was small, and no statistically significant price-dependence
of that variation was found. In fact, the median performance of the
low-cost TVs was slightly better than that of either the mid-priced or
high-priced TVs. The median performance of the tested set-top boxes was
poorer than that of the integrated DTVs by 2.3 dB, though it must be
noted that these were older designs (2004 and earlier models that were
still on the market at the time of this report) than the DTVs.

In the high-VHF and the UHF bands, the variation in reception
performance with price was judged to be both small and not statistically
significant. The median performance of the high-cost TVs differed from
that of the low-cost TVs by less that 0.2 dB. Set top boxes exhibited
median performance 0.6 dB and 0.7 dB worse than the median of all TVs in
the low-VHF and UHF bands, respectively.

### For Difficult Multipath Conditions

The tested receivers fell into two distinct tiers of multipath-handling
capability---the upper tier representing a significant performance
improvement associated with at least two companies' newest generation of
demodulator chips.

Given that both tiers of performance appeared in all three price ranges
of DTV receivers, there appears to be no inherent price dependence among
the DTVs; however, there was a complete absence of upper-tier performers
among the tested set-top boxes. This absence is attributed to the older
designs of the set-top box products---all of which were introduced in
the year 2004 or earlier. Among the tested receivers, none that were
introduced before March 2005 were found to exhibit upper-tier
performance, whereas 48 percent of those introduced in or after that
month performed at the upper tier level.

## Reception Performance Relative to OET-69 {#reception-performance-relative-to-oet-69 .unnumbered}

### For Benign Multipath Conditions

The results show no clear need to adjust planning factors in OET-69 for
application to SHVERA. Table 8‑1 shows that, for benign multipath
conditions, the poorest performing receiver category---*set-top
boxes*---exhibited median performance (as indicated by minimum signal at
TOV) closely matching predictions based on current OET-69 planning
factors, with median performance exceeding the OET-69 predictions by 1.7
dB in high VHF and falling below OET-69 performance levels by less than
1 dB in low VHF and UHF. The median low-cost DTV performance matched
OET-69 in the UHF band and was better than OET-69 by about 2 dB in the
VHF bands. It should be noted that the tolerance on these measurements
is about ±1 dB.

\[It is also noted that, in terms of minimum signal at TOV, the overall
median performance of the tested receivers (-82.2, -83.2, and -83.9 dBm,
in low VHF, high VHF, and UHF, respectively) matches, within measurement
accuracy, the minimum performance standard of -83 dBm recommended by the
ATSC.[^303]\]

[]{#__RefHeading___Toc118693190 .anchor}Table 8‑1. Net Performance for
Unimpaired Signal Relative to OET-69 Model

  --------------- ----------------- ------------------- ------------------
  **Band**        **Median of All   **Median Low-Cost   **Median Set-Top
                  Test Samples**    DTV**               Box**

  **Low VHF       1.2 dB better     2.3 dB better       0.7 dB worse
  (Ch.3)**                                              

  **High VHF      2.2 dB better     2.4 dB better       1.7 dB better
  (Ch.10)**                                             

  **UHF (Ch.30)** 0.1 dB worse      0.1 dB better       0.8 dB worse
  --------------- ----------------- ------------------- ------------------

A breakdown of the results by individual planning factors is shown in
Table 8-2. Median required carrier-to-noise ratios (CNRs) closely match
the OET-69 value, as does the system noise figure in UHF. The median VHF
noise figures of the tested receivers were better than the OET‑69
values, with the exception of the set-top box median in low VHF, which
was only 0.5 dB above (worse than) the OET‑69 value.

[]{#__RefHeading___Toc118693191 .anchor}Table 8‑2. Planning Factor
Measurements with Unimpaired Signal

  ----------------------- ------------ -------------- ----------- -----------
  **Planning Factor**     **OET-69**   **Overall      **Median\   **Median\
                                       Median of Test Low-Cost    Set-Top
                                       Samples**      DTV**       Box**

  **Required              15.2[^304]   15.3           15.3        15.4
  Carrier-to-Noise Ratio                                          
  (dB)**                                                          

  **System Noise Figure   10.0         8.8            7.4         10.5
  (dB) in Low VHF**                                               

  **System Noise Figure   10.0         7.6            7.5         7.8
  (dB) in High VHF**                                              

  **System Noise Figure   7.0          6.9            6.9         7.5
  (dB) in UHF**                                                   
  ----------------------- ------------ -------------- ----------- -----------

Note: for all parameters, lower values correspond to better performance

### Adjustment for Multipath

The required CNRs presented above were measured for an unimpaired
signal. In the presence of significant multipath, it is known that
higher CNRs are required. We have performed no measurements of this
effect on the current generation of receivers; however, field tests from
the year 2000 yielded a value of 16 dB for the median required CNR
across 50 test sites using the then newest generation of DTV receiver
hardware and an outdoor, mast-mounted antenna. This is only 0.7 dB above
the median measured value from the receiver tests using a benign signal.
If the net performance data of Table 8‑1 were degraded by 0.7 dB to
reflect this value for required CNR, it can be seen that the results
would still closely match OET-69 predictions.

### Overall Conclusion Regarding Adjustment to Planning Factors 

While adjustments to the OET-69 planning factors could be made based on
the test results presented in this report in combination with results
from the year-2000 field tests, the overall effect on performance
predictions would be small. Combining the 16-dB required CNR value, as
discussed above, with the overall median noise figures would yield more
optimistic predictions that the current OET-69 by 0.4 dB and 1.6 dB,
respectively, in the low-VHF and high VHF bands, and less optimistic
predictions by 0.7 dB in the UHF band. Given the tolerances on the
measurements, such adjustments to the existing methodology are not
recommended.

#######  TEST CONFIGURATIONS, ISSUES, AND PROCEDURES

## Test Configurations {#test-configurations-1 .unnumbered}

This appendix provides additional information regarding test
configurations, procedures, and issues that arose during the testing.

### General Information on the Test Configurations

All test and measurement setups maintained a 50-ohm impedance
throughout, except at the signal source and the consumer TV inputs,
which were each specified to be nominally 75 ohms. (An older,
instrumented reference receiver identified as 2000REF in this report had
a 50 ohm input impedance.) The 75‑ohm devices were matched to the rest
of the test setup through minimum-loss impedance-matching pads, except
that, in the test setup that employed a splitter, an impedance-matching
transformer was used at the signal source to reduce losses.

Attenuation pads were used throughout each test configuration to reduce
the effects of any impedance mismatches at places where such mismatches
were considered likely or would be expected to have a significant
impact. A 50-to-75-ohm impedance-matching pad used at the input of each
consumer DTV receiver served both as an impedance-matching device and as
a 5.8-dB attenuator to attenuate reflections due to deviations of the TV
antenna inputs from the nominal 75-ohm value.[^305]

### Splitter Test Configuration

Figure A-1 shows a block diagram of the "splitter test configuration",
which was used for tests of white noise threshold and multipath
performance.

An RF player (Sencore RFP-910) playing the "Hawaii_ReferenceA" file
supplied with the player was used as the ATSC 8-VSB signal source, for
reasons discussed in the "Test Issues" section of this appendix.
Amplifiers for the signal operated at RMS levels that were more than
17-dB below the specified 1-dB compression points in order to ensure
linearity.

For the white noise tests, noise was supplied by a noise generator,
which was then externally filtered to roll off the noise beyond 700
MHz---well above the tested frequencies.

Both signal and noise levels were adjusted using step attenuators that
could provide 0 to 81 dB of attenuation in 0.1‑dB steps.

Signal and noise were combined using a directional coupler, then divided
nine ways by means of two cascaded layers of three-way splitters, each
specified to have a minimum isolation of 14 dB between inputs. The
splitters were followed by 25-foot long, well-shielded, low-loss cables,
each of which drove either an impedance-matching pad (nominally 5.8‑dB
power attenuation) for connection to a consumer TV receiver or a 50-ohm
attenuator pad (nominally 6‑dB attenuation) for connection to measuring
instruments or to the instrumented receiver. The nine outputs---at the
output of the final pads---are designated by port numbers Pt1, ... Pt9
when the final pad is an impedance-matching pad, as when driving a
consumer DTV. An "a" is suffixed onto the port numbers when the final
pad is a 50-ohm pad, as when driving a measurement instrument (vector
signal analyzer or spectrum analyzer) or an instrumented receiver having
a 50-ohm input impedance. Port Pt5a was always used as the measurement
port.

The splitter arrangement allowed the signal and noise to be
simultaneously delivered to as many as eight TVs and to a vector signal
analyzer used for measurements. Any amplitude mismatch between the
various ports, though small, was not of concern because the signal
levels for multipath testing were not critical and because white noise
threshold tests involve the ratio of two measurements (signal and noise)
that were made on the same port and using the same amplitude range of
the spectrum analyzer to eliminate the effect of small errors in
absolute measured levels.

### Minimum Signal Test Configuration

Figure A-2 is a block diagram of the configuration used for measuring
minimum signal at TOV.

An RF player (Sencore RFP-910) playing the "Hawaii_ReferenceA" file
supplied with the player was used as the ATSC 8-VSB signal source, for
reasons discussed in the "Test Issues" section of this appendix.

Because minimum input signal at TOV is an absolute measurement rather
than a ratio, a signal splitter was not used for these tests. The
25-foot low-loss coaxial cable carrying the signal was connected through
a 10 dB attenuator and an impedance matching pad (50 to 75 ohms, 5.8 dB
power attenuation) to the TV input. After signal level was adjusted to
achieve TOV on the TV, the cable and 10-dB pad---but not the impedance
matching pad---were moved to the vector signal analyzer input for the
signal level measurement, which then had to be corrected for measured
loss of the impedance matching pad.

## Calibration and Signal Quality Tests on Test Setups {#calibration-and-signal-quality-tests-on-test-setups .unnumbered}

### Impedance-Matching Devices

The power loss of 14 identical minimum-loss impedance-matching pads
(Trilithic model ZM-57) and two impedance-matching transformers
(Trilithic ZMT-57) were measured as a function of frequency. The devices
were labeled with individual numbers for identification; designations
were MLP#1 through MLP#14 for the minimum-loss impedance-matching pads
and TT#1 and TT#2 for the transformers.

The losses of the individual impedance matching devices were determined
from loss measurements performed on back-to-back pairs of
impedance-matching devices. These measurements were performed by
measuring signal levels versus frequency for a tracking generator signal
and for that signal as attenuated by a back-to-back pair of
impedance-matching devices (50 ohms to 75 ohms to 50 ohms) to determine
the loss versus frequency for each tested pair of devices. (Loss was
computed by subtracting the measured output level versus frequency of
the tested devices from the output level versus frequency of the
tracking generator, measured with the same spectrum analyzer settings
\[including input attenuation and reference level\] in order to ensure
that loss measurements were accurate.) The measured combinations
included MLP#13 with each of the other devices and MLP#14 with each of
the other devices. The difference between losses of MLP#13 and MLP#14
was computed as the difference between average loss of the combinations
of MLP#13 with MLP#1 through MLP#12 and average loss of the combinations
of MLP#14 with MLP#1 through MLP#12. The loss of MLP#13 combined with
MLP#14 determined the sum of losses of MLP#13 and MLP#14. Combining this
information allowed computation of the individual losses of MLP#13 and
MLP#14. The loss of each of the other devices could then be computed by
subtracting the loss of MLP#13 from the measured loss of the combination
of that device with MLP#13, or by performing a similar calculation based
on MLP#14; in fact, both computations were performed and the results
averaged to determine the loss of those devices.

The unit-to-unit variation of the loss of the impedance matching pads at
channel-30 frequencies was of interest because of their use in the
splitter test setup. The pads were found to be quite well matched---with
samples ranging from 5.79 to 5.84 dB at the frequency of TV channel 30.

All of the pads and both transformers were found to be flat to within
0.02 dB across the 6‑MHz bandwidths of each tested channel (3, 10, and
30).

TV-channel-specific measurements of absolute loss of one impedance
matching pad (MLP#12) were used in determining minimum signal at TOV
because the actual signal level measurement did not include the loss of
that pad. Those losses were 5.70, 5.73, and 5.82 dB, respectively, on
channels 3, 10, and 30.

The frequency-dependent measurements of the loss of one
impedance-matching transformer (TT#1) were used in determining the
frequency response of the splitter test configuration to the 50-ohm
outputs (Pt5a and Pt8a).

### Splitter Test Configuration

Because of the complexity of the splitter test configuration, which
included amplifiers, a noise generator, a directional coupler, and
splitters that were not a part of the simpler minimum-signal test
configuration, additional tests were performed to verify its
performance. The tests evaluated the frequency response (including the
potential effect of errors in input impedance of the TVs), port-to-port
matching, signal and noise spectral characteristics, and signal quality.

#### Frequency Response and Effect of Mismatched Loads {#frequency-response-and-effect-of-mismatched-loads .unnumbered}

The splitter test configuration (Figure A-1) provided nine identical
output ports, each of which could be configured for connection to a
75-ohm device (the antenna port of a consumer DTV) or to a 50-ohm device
(vector signal analyzer, spectrum analyzer, or an instrumented reference
receiver having 50 ohms input impedance). Configuration of each port was
performed by connection of either an impedance-matching pad (50 to 75
ohms, 5.8 dB nominal power attenuation) or a 50-ohm pad (6 dB ±0.5 dB)
at the final output of the port (end of the 25-foot low loss cable). The
ports were designated Pt1, ... Pt9 when matched to 75 ohms. A suffix "a"
was added to the designation of ports matched to 50 ohms. Only two ports
were ever configured for 50 ohms during the reported tests: the fifth
port (Pt 5a), which always served as the measurement port; and the eight
port (designated Pt8a, when so configured), which was used to connect to
the instrumented, 50-ohm input receiver designated 2000REF for one set
of tests.

Figure A-3 shows the frequency response of the entire test setup from
the output of the ATSC signal source (PtA in Figure A-1) to each of the
final output ports. For port 8, separate results are shown for the Pt8
and Pt8a configurations. During the measurements, all ports except that
being measured were terminated in the appropriate impedance---either 50
or 75 ohms. The response of each port was flat to well within 0.1 dB
(maximum -- minimum) across the 6-MHz bandwidth of TV channel 30. The
gain of each 75-ohm port matched that of the measurement port (Pt5a)
within 0.2 dB.

A test was also performed to determine whether frequency response on one
port would be significantly affected by impedance mismatches on other
ports, since consumer TVs may not have carefully controlled input
impedance. Figure A-4 shows three frequency response plots measured on
Port Pt5a under three different load conditions for the other eight
ports: ideal terminations (75 ohms), actual TVs (tuned to channel 30),
and open circuits. With TV's as loads the frequency response across
channel 30 remained flat to well within 0.1 dB. With open circuits on
all eight ports, flatness degraded somewhat, but was still well within
0.2 dB across channel 30.

All of the above tests were performed by using a spectrum analyzer and
tracking generator, as shown in Figure A-5. In all cases the tracking
generator signal (connected through an attenuator pad to stabilize the
impedance) was injected at PtB in Figure A-1 so that a 50-ohm source
could be used. For frequency response tests of 75-ohm ports, the losses
in TT#1, the impedance-matching transformer that normally connected the
75-ohm ATSC source to PtB, were included by using TT#1 to match the
impedance of the selected port to the 50-ohm input of the spectrum
analyzer. For frequency response tests of 50-ohm ports, TT#1 was omitted
from the measurement, but its losses as a function of frequency
(measured separately) were included in the computed frequency response.
In all cases, the tracking generator signal---as attenuated by the 10-dB
pad shown in Figure A-5---was measured by the spectrum analyzer as a
reference in the frequency response calculations. All measurements were
performed with the same spectrum analyzer settings (including input
attenuation and reference level) in order to ensure accuracy of the
computed frequency response function.)

#### Signal Spectrum, Noise Spectrum, and Signal Quality {#signal-spectrum-noise-spectrum-and-signal-quality .unnumbered}

Spectrum and modulation error ratio measurements indicate that a high
quality test signal and spectrally flat noise were delivered to the
output ports of the test setup.

Figure A-6 shows spectra of the injected signal and noise as measured at
Pt5a during playback of the "Hawaii_ReferenceA" file from the RF capture
player at a CNR of 15 dB. The spectra were measured with a 30‑kHz
resolution bandwidth, 300‑kHz video bandwidth, RMS detection, and
trace-averaging (in linear power units) of 8192 traces. (This averaging
was performed across multiple loops of the test signal). The noise
spectrum is flat across the 6‑MHz bandwidth of TV channel 30 to within
0.34 dB (maximum -- minimum) for the spectrum as shown and to within
0.11 dB when a 500‑kHz smoothing width is applied to average out some of
the randomness of the measurement. Similarly, the signal spectrum is
flat across the 4.76‑MHz wide "head" (i.e., flat part) of the ATSC
signal to within 0.59 dB for the spectrum as shown and 0.38 dB when
500‑kHz smoothing is applied.

Modulation error ratio (MER) measured by the vector signal analyzer
during the tests of required CNR was a respectable 33 to 35 dB without
including any equalization in the vector analyzer and 37 dB with
equalization.

#### Other Checks {#other-checks .unnumbered}

A test was performed to ensure that any impedance mismatch at PtC in
Figure A-1 would not affect the level of injected noise from the noise
generator through the resulting variations in impedance at the signal
input to the directional coupler as the signal step attenuator was
varied. The noise level step attenuator was adjusted to achieve -70 dBm
noise level at Pt5a. Amplifier A2 was then replaced by a short circuit
at PtC and the noise level at Pt5a was measured for two different
settings of the signal attenuator---0 dB and 81 dB. The measured
variation in noise power was only 0.01 dB.

To ensure that amplifier A2 (Figure A-1) was not operated in a
non-linear region that might affect signal quality, the signal level at
the output of A2 was measured during playback of the "Hawaii_ReferenceA"
file. The measured level was 17.5 dB below the 1-dB compression point of
the amplifier.

Signal-to-noise ratio of the signal path (excluding any noise generated
by the RF player) was measured to ensure that amplifier noise (from A1
and A2 in Figure A‑1) did not significantly affect results. SNR in a
6‑MHz bandwidth was found to be 64 dB on channel 30.

## Test Issues {#test-issues .unnumbered}

A few observations regarding issues that arose during the test program
may be of value to others who perform DTV receiver performance testing.

### Multipath Performance Testing Using the RF Player

After we had tested 16 DTV receivers against each of the 47 RF captures,
visiting engineers from a DTV chipset developer (ATI Research) observed
video errors on one of the TVs during playback of a few captures. Though
all tested TVs were able to play some of the captures with no visible
errors, the visiting engineers suggested that the errors observed on
some specific captures indicated that the FCC's RF player was not
functioning properly. This conclusion was based on two factors: (1) they
had tested a TV with the same technology at their labs and found it had
produced no visible errors on those specific captures; (2) they reported
having had problems with several of their own RF capture players that
produced visible errors which went away after calibration and repair of
the player.

Based on these observations, we sent our RF player back to the
manufacturer for repair and calibration; the manufacturer indicated that
our problem had been caused by a ground plane error on one of the cards.
After they replaced that card and recalibrated the unit, the difference
was dramatic. A TV that had successfully handled only 10 of the captures
with no visible errors before the repair was able to handle 31 of the
captures without visible errors after the repair. We subsequently
discarded all previous results and repeated all testing.

As an additional confirmation of performance of our RF player---in
conjunction with our entire splitter-based test setup, ATI allowed us to
test two DTV samples (subsequently identified as "upper tier" performers
in Chapter 6) at their laboratories using their equipment. The net test
results (number of captures played with no visible errors and number
played with no more than two visible errors) at the FCC using our test
setup with our repaired RF player matched those that we performed at ATI
for one of the TVs. For the other TV, the tests at the FCC showed three
more captures producing two or fewer errors (including zero errors), but
showed two fewer captures producing no errors. Given the variability in
results that sometimes occur between playback loops along with the
subjective judgment in identifying visual errors, these differences were
considered acceptable.

### RF Source for Measurements of White Noise Threshold and of Minimum Signal

Our plan had been to use the RF player as an ATSC source only when
performing multipath testing. An ATSC signal generator was to be used
for testing of white noise threshold and of minimum signal at TOV.

In initial tests of 16 DTV receivers using the signal generator as a
source, the white noise threshold of the best tested receiver was found
to be 15.25 dB. This was slightly higher than the 14.9 to 15.0 dB that
had been expected for the better-performing receivers; consequently, the
generator was sent back to its manufacturer for calibration and
checkout. Upon its return, retesting of that best performing receiver
yielded a white noise threshold 16.0 dB---indicating degraded signal
quality.

After the poor result with the signal generator, white noise threshold
was measured again, but this time using the RF player and a
laboratory-recorded DTV signal file designated "Hawaii_ReferenceA" as
the signal source. The measured white noise threshold of that same
receiver was then found to be 14.94 dB. Based on these results, the ATSC
signal generator was replaced by the RF player, which was then used for
all testing reported herein. (Previous test results were discarded and
all tests were repeated.)

### Getting DTV Receivers to Recognize a DTV Signal

The channel-selection "intelligence" of many DTVs combined with certain
artificialities of laboratory-based testing to create some challenges.

With analog television, to receive a signal on a given TV channel you
simply select that channel. With DTV, there is another layer involved
channel selection. To simplify the DTV transition for the consumer, a
DTV signal includes coding that tells the TV the channel number of the
analog station that is associated with that DTV signal. In Washington,
DC, for example, the DTV broadcast on channel 48 includes information
linking it to an analog broadcast on channel 4. A TV viewer not aware of
the digital broadcast on channel 48 can tune to a channel he or she may
already view---channel 4---and the digital television will automatically
set its tuner to channel 48 to select the digital broadcast containing
the same programming as the viewer would have seen on analog channel 4.

To facilitate this extra layer in channel selection, DTVs include a
channel scan function that is used on initial setup of the TV. The
function causes the tuner to sequence through all TV channels searching
for analog and digital signals. It creates a mapping from the analog
channel numbers to the digital ones and may also identify available
sub-channels on each DTV broadcast, since the DTV transmission system
enables transmission of more than one program within a single RF TV
channel. Many of the TVs will not allow a DTV signal to be received
unless it has been identified by such a scan.

The laboratory tests described in this report created two types of
anomalies---one associated with the tests of minimum signal at TOV and
the other associated with multipath testing using the RF captures.

The minimum signal tests were performed on channels 3, 10, and 30. The
available equipment allowed creation of the signal on only one channel
at a time; consequently, any channel scan identified only one channel,
and when the channel was changed for the next set of tests, the channel
scan had to be repeated.

For the multipath testing, a less obvious problem occurred. All testing
was performed on channel 30, so one might expect that a single channel
scan on each TV would enable testing with all 47 captures. While this
worked for some TVs, it did not for others. The original source material
for the captures was recorded from eight DTV channels in two cities.
Many of the receivers were "confused" by changing broadcast stations
(from one capture to the next), even though the RF channel remained
constant. Many would not allow selection of the signal as channel 30;
instead, the signal had to be tuned indirectly by selecting the channel
number of the analog broadcast associated with the recorded digital
broadcast---which could only occur after a channel scan.

Thus, each time that an RF capture was loaded, if it originated from a
different broadcast station from the last, steps had to be taken to
ensure that each TV recognized the new signal. The necessary steps
varied among the TVs. Some immediately displayed the new video. For
others, simply pressing the channel up or down button caused the signal
to be selected. For TVs requiring a new channel scan, some allowed the
user to select a single channel number to rescan (channel 30 in this
case), while other required a more time consuming rescan of all
channels. For some TVs, even a complete rescan was not sufficient to
lock in the new signal; unplugging the TV from its power source followed
by a channel rescan was usually sufficient in those cases.

To save time in the multipath testing process, the captures were sorted
by originating broadcast station before testing. This reduced the number
of transitions between broadcast sources so that fewer channel scans
would be necessary. To further assist in testing, the captures were
sorted---within each originating channel group---to allow the more
benign captures from a given broadcast station to be played first in
order to lock the receivers onto each new broadcast station using a
signal for which success would be likely. It was found, however, that
during subsequent testing with captures exhibiting more challenging
multipath conditions, some TVs would change channels---or even turn
off---during the period when no recognizable signal was received.
Consequently, it was often necessary to return to an easier capture from
the same broadcast source at various times during the testing to ensure
that the TVs were still locked on to that broadcast.

## Procedures {#procedures .unnumbered}

Test procedures applicable to the DTV measurements conducted for this
report are shown below.

### General

The following procedures apply to all measurements.

1.  Warmup

    1.  Allow all test equipment (signal and noise sources, amplifiers,
        measurement equipment) to warm up for a minimum of 2 hours
        before testing.

    2.  Allow all TVs to warm up at least one hour before testing

2.  Test equipment calibration

    1.  Before each measurement sequence using the spectrum analyzer,
        perform a full alignment---including RF alignment requiring an
        external cable connection to the built in calibrated source.
        (Spectrum analyzer is used only for measurements of test
        configuration parameters such as frequency response and output
        spectrum.)

    2.  Before each measurement sequence using the vector signal
        analyzer, invoke the "single cal" function to calibrate the
        instrument.

3.  Measurement of applied signal and noise levels

    1.  Use averaging times of approximately 21 seconds (1200 averages
        on vector signal analyzer) when measuring signal levels and
        ensure that the averaging interval begins just after the start
        of a playback loop on the RF player and ends before completion
        of that loop in order to avoid averaging across the loop
        restart.

    2.  For measurements of noise levels, use averaging times 21
        seconds.

4.  Identifying visual errors in video

    1.  Allow the RF player to play the selected signal through at least
        three complete loops before making observations.

    2.  Do not count errors occurring at each loop restart of the RF
        player

    3.  Do not count errors associated with known recording defects due
        to dropped symbols (Appendix B)

    4.  Horizontal streaks occupying a single scan line are judged to be
        defects in video source material prior to conversion to MPEG
        format for broadcast and are not counted.

    5.  For an error burst lasting longer than one second, count the
        number of errors as the approximate duration of the burst in
        seconds.

### White Noise Threshold Tests

Note that all measurements are performed using the vector signal
analyzer (VSA), and all attenuator settings and measurements are entered
into a spreadsheet that performs the required computations.

1.  Connect equipment as shown in Figure A-1

2.  VSA setup

    1.  Run DTV measurement software[^306]

    2.  Set number of averages to 2000

    3.  Set broadcast channel 30

    4.  Execute "single cal"

    5.  Set amplitude range to -50 dBm (most sensitive range)

3.  RF player setup

    1.  Load "Hawaii_ReferenceA" file

    2.  Set output channel to 30

    3.  Set output level to -30 dBm

4.  Noise generator setup

    1.  Set the internal noise attenuator to 0 dB

5.  Measure VSA self noise by connecting a 50-ohm termination to the VSA
    input and performing a "long average power" measurement. (This value
    will be subtracted---in linear power units---from all subsequent
    measurements.).

6.  Connect the VSA to Pt5a (Figure A-1)

7.  Measure modulation error ratio (MER) as an indication of signal
    quality

    1.  Set noise attenuator to 81 dB

    2.  Set signal attenuator to point at which VSA indicates occasional
        clipping (typically 24 dB attenuation) in order to maximize
        signal to VSA-noise ratio

    3.  Measure MER four times and average the results. The measurements
        are performed without any equalization in the VSA.

8.  Set and measure injected noise level

    1.  Set signal attenuator to 81 dB

    2.  Adjust noise attenuator to the 0.1-dB step that most closely
        yields a "long average power" reading of -70 dBm

    3.  Measure the "long average power" twice. (Actual injected noise
        power will be computed by averaging these two measurements with
        two similar measurements performed after the TV tests and
        subtracting---in linear power units---the VSA self noise. Though
        the correction for VSA self noise is performed in the
        spreadsheet, the correction is essentially negligible because
        VSA self noise is about 27 dB below the injected noise level.)

9.  Set signal to a high level and take whatever steps are necessary to
    ensure that all connected TVs are tuned to the signal and producing
    a picture.

10. TV tests. Repeat for each of the connected TVs (typically eight).
    Include receiver D3 in each test sequence as a consistency check.

    1.  Adjust signal level upward as necessary to obtain a picture

    2.  Adjust signal level downward until picture either drops out or
        exhibits a high visual error rate

    3.  Adjust signal level upward in 0.1‑steps to achieve the lowest
        signal level that produces a picture that is free of visual
        errors for 10 seconds. Record this attenuator setting.

    4.  Adjust signal level upward in 0.1‑steps as needed to achieve the
        lowest signal level that produces a picture that is free of
        visual errors for 60 seconds. Record this attenuator setting.

        1.  As a consistency check, the spreadsheet computes difference
            between attenuator setting in previous step and current
            attenuator setting. This difference is typically between 0
            and 0.2 dB.

    5.  Perform "long average power" measurement as described below.
        This measurement represents the total of the injected signal
        level, the injected noise level (typically about 15 dB below the
        injected signal level), and the VSA self noise (typically about
        42 dB below the injected signal level).

        1.  The measurement should be initiated near the end of a
            playback loop, so that---following the initial operations
            performed when "long average power" is selected---the actual
            long integration will begin just after the start of the RF
            playback loop. The reading of average power should be taken
            just before the end of that playback loop.

        2.  As a consistency check, the spreadsheet calculates the sum
            of the signal attenuator setting and the measured power
            level. This sum should be nearly constant across all TV
            measurements.

        3.  Spreadsheet calculates injected signal level by
            subtracting---in linear power units---the injected noise
            level and the VSA self noise from the measured power. The
            injected noise level subtraction typically results in a
            correction slightly larger than 0.1 dB. The VSA self noise
            correction is negligible.

        4.  Injected signal-to-noise ratio (SNR), termed the
            carrier-to-noise ratio (CNR) in this report, is computed. (A
            subsequent adjustment is made for TV self-noise---based on
            measurements of minimum signal at TOV; however, this
            correction is essentially negligible.)

    6.  Confirm that the measured level is sufficient for relocking on
        to the DTV signal.

        1.  Reduce signal level by 20 dB for 20 seconds. Return to
            previous level and verify that the TV recaptures the signal.

    7.  Repeat steps for other TVs

11. Measure injected noise level

    1.  Set signal attenuator to 81 dB

    2.  Measure the "long average power" twice for use as described
        following 1^st^ measurements of injected noise level.

Because both the injected noise power measurement and the injected
signal measurement were performed using the same vector signal analyzer
on the same amplitude range, the CNR is expected to be quite accurate,
since it doesn't depend on the absolute calibration accuracy of the
measuring instrument.

Additional information on the testing is included in the "Measurement
Method" section of Chapter 3.

### Minimum Signal Tests

Note that all measurements are performed using the vector signal
analyzer (VSA), and all attenuator settings and measurements are entered
into a spreadsheet that performs the required computations. The tests
are performed for TV channels 3, 10, and 30.

12. Connect equipment as shown in Figure A-2.

13. VSA setup

    1.  Run DTV measurement software[^307]

    2.  Set number of averages to 1200

    3.  Set selected broadcast channel

    4.  Execute "single cal"

    5.  Set amplitude range to -50 dBm (most sensitive range)

14. RF player setup

    1.  Load "Hawaii_ReferenceA" file

    2.  Set output channel to selected channel

    3.  Set output level to -30 dBm

15. Measure VSA self noise three times by connecting a 50-ohm
    termination to the VSA input and performing a "long average power"
    measurements. (The average of these measurements will be
    subtracted---in linear power units---from all subsequent
    measurements.)

16. TV tests. Repeat for each of TV to be tested (typically eight).
    Include receiver D3 in each test sequence as a consistency check.

    1.  Connect output of the test setup through impedance-matching pad
        MLP#12, as shown by the solid lines on the right side of Figure
        A-2.

    2.  Set signal to a high level and take whatever steps are necessary
        to ensure that TV is tuned to the signal and producing a
        picture.

    3.  Adjust signal level downward until picture either drops out or
        exhibits a high visual error rate

    4.  Adjust signal level upward in 0.1‑steps to achieve the lowest
        signal level that produces a picture that is free of visual
        errors for 10 seconds. Record this attenuator setting.

    5.  Adjust signal level upward in 0.1‑steps as needed to achieve the
        lowest signal level that produces a picture that is free of
        visual errors for 60 seconds. Record this attenuator setting.

        1.  As a consistency check, the spreadsheet computes difference
            between attenuator setting in previous step and current
            attenuator setting. This difference is typically between 0
            and 0.2 dB.

    6.  Perform "long average power" measurement as described below.

        1.  The measurement should be initiated near the end of a
            playback loop, so that---following initial operations
            performed when "long average power" is selected---the actual
            long integration will begin just after the start of the RF
            playback loop. Confirm that the integration ends before
            completion of the playback loop.

        2.  As a consistency check, the spreadsheet calculates the sum
            of the signal attenuator setting and the measured power
            level. This sum should be nearly constant across all TV
            measurements.

        3.  Spreadsheet calculates injected signal level by
            subtracting---in linear power units---the VSA self noise
            from the measured power (a correction that is typically less
            than 0.1 dB) and then subtracting (in dB) the power loss of
            impedance-matching pad MLP#12 for the specific TV channel
            tested.

    7.  Repeat steps for other TVs

Additional information on the testing is included in the "Measurement
Method" section of Chapter 4.

### Multipath Tests (RF Captures)

Note that in-band injected signal power (6-MHz bandwidth centered at
channel 30) was measured at Pt5a (Figure A‑1) using the vector signal
analyzer (VSA) for each of the 47 RF captures during tests of the first
group of eight receivers. These measurements were not repeated for
subsequent receivers because small variations in absolute signal level
applied to the receivers were not expected to affect the results.

17. Connect equipment as shown in Figure A-1

18. VSA setup

    1.  Run DTV measurement software[^308]

    2.  Set number of averages to 2000

    3.  Set broadcast channel 30

    4.  Execute "single cal"

    5.  Set amplitude range to -20 dBm

19. RF player setup

    1.  Set output channel to 30

    2.  Set output level to -30 dBm

20. Signal and noise attenuators

    1.  Set signal attenuator to 0 dB. This was found to provide a
        median in-band signal power of ‑29.7 dBm across the 47 RF
        captures. This is 53 dB above the minimum signal level at TOV
        for typical receivers; consequently, any variations in absolute
        level among the captures was not expected to affect the test
        results.

    2.  Set the noise attenuator to 81 dB to effectively eliminate
        injected noise.

21. Measure modulation error ratio (MER) as an indication of signal
    quality.

    1.  Load "Hawaii_ReferenceA" file

    2.  In the first series of tests, MER was measured twice with
        internal equalizer off. The average of the measurements was 35.5
        dB.

22. Tests for a given capture\
    (Note that captures are loaded and tested sequentially in groups for
    which the originating TV broadcast channel is the same. Within each
    group, captures that are deemed to be easier to acquire---due to
    benign multipath conditions---are loaded first to increase the
    likelihood of a successful channel scan on each TV.)

    1.  Load the selected RF capture

    2.  Ensure signal acquisition for all TVs, to the extent possible

        1.  If this capture corresponds to a different broadcast TV
            channel than the last capture, take whatever steps are
            necessary to ensure that all connected TVs are tuned to the
            signal and have an opportunity to produce a picture. This
            may include channel scans or disconnecting power. To improve
            probability of success, the first capture loaded should have
            as benign multipath conditions as possible.

        2.  If this capture corresponds to the same broadcast TV channel
            as the last, then check to see that all TVs have acquired
            the signal (i.e., are producing a TV picture). If not, try
            channel scans or returning to a more benign capture from the
            same broadcast channel to achieve acquisition.

    3.  Wait for at least three full playback loops to be completed
        before judging TV receiver performance.

    4.  TV tests. Repeat for each of the connected TVs (typically
        eight). Include receiver D3 in each test sequence as a
        consistency check.

        1.  Observe video on the selected TV and count the number of
            video errors observed during a single playback loop. If
            performance is monitored over several loops and, if the
            results vary, select the median number of errors as the
            value to record. A video error burst lasting more than one
            second is counted based on the approximate duration in
            seconds. Thus, an error burst lasting three seconds is
            counted as three errors. Errors occurring during or
            immediately after the loop-restart time are not counted, nor
            are errors associated with known defects (dropped symbols)
            in eight of the captures, as documented by the ATSC.[^309]

        2.  Repeat for next TV

    5.  Repeat for next RF capture

Additional information on the testing is included in the "Measurement
Method" section of Chapter 4.

## Equipment {#equipment .unnumbered}

Table A-1 identifies the equipment used for the tests that were
conducted for this report.

[]{#__RefHeading___Toc118693192 .anchor}Table A‑1. Equipment List

+--------+-------+-----------+-----------+-------+-------------------+
| **     | **MO  | **EQ      | **S/N**   | **CAL | **USE**           |
| MAKE** | DEL** | UIPMENT** |           | D     |                   |
|        |       |           |           | ATE** |                   |
+--------+-------+-----------+-----------+-------+-------------------+
| S      | R     | RF Player | 007, Run  | 8/    | ATSC source for   |
| encore | FP910 |           | 11A       | 10/05 | all tests         |
+--------+-------+-----------+-----------+-------+-------------------+
| A      | 8     | Vector    | U         | 9/    | CNR measurements  |
| gilent | 9441A | Signal    | S40514809 | 17/04 | before 8/30/05;   |
|        |       | Analyzer  | /U        |       |                   |
|        |       |           | S39313048 |       | amplitude of      |
|        |       |           |           |       | injected captures |
|        |       |           |           |       | before 8/30/05    |
+--------+-------+-----------+-----------+-------+-------------------+
| A      | 8     | Vector    | U         | 8     | CNR measurements  |
| gilent | 9441A | Signal    | S40514815 | /8/05 | after 8/30/05;    |
|        |       | Analyzer  | /U        |       |                   |
|        |       |           | S39313021 |       | All minimum       |
|        |       |           |           |       | signal            |
|        |       |           |           |       | measurements      |
+--------+-------+-----------+-----------+-------+-------------------+
| A      | E     | Spectrum  | U         | 10/   | Calibration of    |
| gilent | 7405A | Analyzer  | S41160406 | 27/04 | minimum-loss      |
|        |       |           |           |       | i                 |
|        |       |           |           |       | mpedance-matching |
|        |       |           |           |       | pads (6/7/05)     |
+--------+-------+-----------+-----------+-------+-------------------+
| A      | E     | Spectrum  | U         | 8/    | Frequency         |
| gilent | 7405A | Analyzer  | S41160425 | 16/05 | response of       |
|        |       |           |           |       | splitter test     |
|        |       |           |           |       | configuration     |
+--------+-------+-----------+-----------+-------+-------------------+
| Noi    | UFX   | Noise     | P292-0135 | \*\*  | Noise source for  |
| se/Com | -7110 | Generator |           |       | white-noise       |
|        |       |           |           |       | threshold tests   |
+--------+-------+-----------+-----------+-------+-------------------+

Notes:\
\*\* Last factory calibration was 8/21/01, but for the reported tests,
output was calibrated by means of Agilent E7405A spectrum analyzer at
the time of each test.

![](media/image18.wmf){width="5.9944444444444445in"
height="3.3756944444444446in"}

[]{#__RefHeading___Toc118693155 .anchor}Figure A‑1. Block Diagram of
Test Configuration for Required CNR and RF Capture Tests

![](media/image19.wmf){width="5.997916666666667in"
height="1.7006944444444445in"}

[]{#__RefHeading___Toc118693156 .anchor}Figure A‑2. Block Diagram of
Test Configuration for Minimum Signal at TOV

![](media/image20.wmf){width="6.497916666666667in"
height="4.261111111111111in"}

[]{#__RefHeading___Toc118693157 .anchor}Figure A‑3. Frequency Response
of Each Port

![](media/image21.wmf){width="6.497916666666667in"
height="4.267361111111111in"}

[]{#__RefHeading___Toc118693158 .anchor}Figure A‑4. Effect of Load
Impedance Mismatch

![](media/image22.wmf){width="4.550694444444445in"
height="1.0229166666666667in"}

[]{#__RefHeading___Toc118693159 .anchor}Figure A‑5. Calibration
Connection for Test Setup for Required CNR and RF Capture Tests

![](media/image23.wmf){width="6.497916666666667in"
height="4.4430555555555555in"}

[]{#__RefHeading___Toc118693160 .anchor}Figure A‑6. Spectra of Injected
Signal and Noise at 15-dB CNR

#######  SUMMARY OF RF FIELD CAPTURES

Table B-1 lists the 50 ATSC-recommended captures, some of their
characteristics, and the number of consumer DTV receivers (of 28) that
successfully demodulated each capture in tests for this report.

The three captures having no video content (e.g., grey or black screens)
were not tested, except with an instrumented receiver which is not
included in the tabulated results. In counting observed video errors,
errors coinciding with the locations of known symbol drops, as reported
by the ATSC, were not counted. Note that four of the captures on which
no tested receiver achieved demodulation free of visual errors were
identified by the ATSC as having possible non-linearities caused by
high-level adjacent channels overdriving the recording system.

Notes on Table B-1 (next page):

All captures have durations of 23 or 25 seconds

\* Site: HR = high rise apartment; SF = single family home; TH =
townhouse

Antenna: ID = indoors at 6-ft height; OD = outdoors at 30-ft height

\*\*Issues: DS = 48 dropped symbols at specified location; NL =
recording may contain nonlinearities due to strong adjacent channel

[]{#__RefHeading___Toc118693193 .anchor}Table B‑1. RF Field Captures

  ------ --------------------------- ------ ----------- ---------- ------------ ----------- -----------
  File   Original data capture       Chan   Site /      Distance   Known        \# of       \# of
  \#     filename                           Antenna\*   from Tx    Issues\*\*   Receivers   Receivers
                                                        (Miles)                 w/No Errors w/2 Errors

  01     NYC_200_44_10272000_DBT1    44     HR / ID     2.0                     10          10

  02     NYC_200_44_10272000_LOOP1   44     HR / ID     2.0                     0           0

  03     NYC_200_44_10272000_MEGA1   44     HR / ID     2.0                     10          10

  04     NYC_200_44_10272000_RAB1    44     HR / ID     2.0                     10          10

  05     NYC_200_44_10272000_SSEN1   44     HR / ID     2.0                     10          10

  06     NYC_200_44_10272000_SSEN2   44     HR / ID     2.0                     10          10

  07     NYC_200_44_10272000_SSEN3   44     HR / ID     2.0                     0           0

  08     NYC_200_44_10272000_YAGI1   44     HR / ID     2.0                     13          13

  09     NYC_200_56_10272000_BWT1    56     HR / ID     2.0                     2           10

  10     NYC_200_56_10272000_DBT2    56     HR / ID     2.0                     10          10

  11     NYC_200_56_10272000_DSEN1   56     HR / ID     2.0                     10          10

  12     NYC_200_56_10272000_DSEN2   56     HR / ID     2.0                     1           14

  13     NYC_200_56_10272000_LOOP1   56     HR / ID     2.0                     10          10

  14     NYC_200_56_10272000_MEGA1   56     HR / ID     2.0                     11          11

  15     NYC_200_56_10272000_RAB1    56     HR / ID     2.0                     10          10

  16     NYC_200_56_10272000_SSEN1   56     HR / ID     2.0                     0           10

  17     NYC_200_56_10272000_YAG1    56     HR / ID     2.0                     10          10

  18     WAS_06_34_06092000_REF      34     SF / OD     10.8                    8           10

  19     WAS_23_34_06072000_OPT      34     SF / ID     16.7                    28          28

  20     WAS_23_48_06072000_OPT      48     SF / ID     15.5                    0           8

  21     WAS_3_27_06022000_REF       27     SF / OD     48.4                    9           13

  22     WAS_3_35_06022000_REF       35     SF / OD     51.9       No Video     NA          NA

  23     WAS_311_34_06052000_OPT     34     HR / ID     4.3        NL           0           0

  24     WAS_311_35_06052000_REF     35     HR / OD     3.9        No Video     NA          NA

  25     WAS_311_36_06052000_REF     36     HR / OD     4.7                     13          14

  26     WAS_311_39_06052000_OPT     39     HR / ID     4.3                     0           0

  27     WAS_311_48_06052000_REF     48     HR / OD     3.9                     2           11

  28     WAS_32_48_06012000_OPT      48     SF / ID     17.8       NL           0           0

  29     WAS_34_27_06082000_OPT      27     TH / ID     7.5                     7           27

  30     WAS_34_35_06082000_OPT      35     TH / ID     9.6        NL           11          13

  31     WAS_34_48_06082000_OPT      48     TH / ID     9.6                     7           11

  32     WAS_38_34_05312000_OPT      34     TH / ID     14.3       DS@15.0 sec  26          26

  33     WAS_38_34_05312000_REF      34     TH / OD     14.3       DS@15.1 sec  27          28

  34     WAS_38_36_05312000_OPT      36     TH / ID     14.3       DS@22.2 sec  24          24

  35     WAS_47_48_06132000_OPT      48     SF / ID     13.1       DS@13.8 sec  27          28

  36     WAS_49_34_06142000_OPT      34     SF / ID     20.2       Possible DS  0           0

  37     WAS_49_39_06142000_OPT      39     SF / ID     20.2       DS@24.9 sec  10          11

  38     WAS_51_35_05242000_REF      35     SF / OD     20.3                    8           8

  39     WAS_63_34_06212000_OPT      34     SF / ID     12.7                    0           9

  40     WAS_68_36_05232000_REF      36     SF / OD     17.7       NL           0           8

  41     WAS_75_35_06162000_OPT      35     SF / ID     10.0                    0           1

  42     WAS_75_36_06162000_OPT      36     SF / ID     10.9       NL           0           0

  43     WAS_75_39_06162000_OPT      39     SF / ID     10.5                    10          13

  44     WAS_80_35_06152000_OPT      35     TH / ID     9.9        No Video     NA          NA

  45     WAS_81_36_06192000_OPT      36     SF / ID     9.6                     12          27

  46     WAS_82_35_06202000_OPT      35     SF / ID     8.3        DS@17.2 sec  27          28

  47     WAS_83_36_06222000_OPT      36     TH / ID     3.5        DS@14.9 sec  2           5

  48     WAS_83_39_06222000_OPT      39     TH / ID     3.0        DS@12.2 sec  28          28

  49     WAS_86_36_07122000_OPT      36     SF / ID     33.3                    10          10

  50     WAS_86_48_07122000_REF      48     SF / OD     34.4                    1           5
  ------ --------------------------- ------ ----------- ---------- ------------ ----------- -----------

See notes on preceding page

## APPENDIX D {#appendix-d .unnumbered}

##  {#section .unnumbered}

NOTICE OF INQUIRY

**Before the**

**Federal Communications Commission**

**Washington, D.C. 20554**

+----------------------------------+---+------------------------------+
| In the Matter of                 | * | ET Docket No. 05-182         |
|                                  | * |                              |
| Technical Standards for          | ) |                              |
| Determining Eligibility          | * |                              |
|                                  | * |                              |
| For Satellite-Delivered Network  |   |                              |
| Signals Pursuant                 | * |                              |
|                                  | * |                              |
| To the Satellite Home Viewer     | ) |                              |
| Extension and Reauthorization    | * |                              |
| Act                              | * |                              |
|                                  |   |                              |
|                                  | * |                              |
|                                  | * |                              |
|                                  | ) |                              |
|                                  | * |                              |
|                                  | * |                              |
|                                  |   |                              |
|                                  | * |                              |
|                                  | * |                              |
|                                  | ) |                              |
|                                  | * |                              |
|                                  | * |                              |
|                                  |   |                              |
|                                  | * |                              |
|                                  | * |                              |
|                                  | ) |                              |
|                                  | * |                              |
|                                  | * |                              |
+----------------------------------+---+------------------------------+

**NOTICE OF INQUIRY**

**Adopted: April 29, 2005 Released: May 3, 2005**

**Comment Date: 30 Days after Publication in the Federal Register**

**Reply Comment Date: 45 Days after Publication in the Federal
Register**

**By the Commission:**

1.  By this action, the Commission begins an inquiry into the adequacy
    of the digital signal strength standard and testing procedures used
    to determine whether households are eligible to receive distant
    broadcast digital television (DTV) network signals from satellite
    communications providers. We request comment and information on
    whether the existing statutes and/or regulations concerning the
    digital television signal strength standard and testing procedures
    as used for identifying if households are unserved by local network
    TV signals for purposes of determining eligibility to receive
    distant signals from satellite services need to be revised. We
    specifically intend to study whether such statutes and regulations
    should be revised to take into account the types of antennas that
    are available to consumers. The record obtained through this inquiry
    will be used to prepare a report to Congress describing the results
    of this study and the Commission's recommendations, if any, for
    changes that should be made to the applicable Federal statutes or
    regulations. In this proceeding, we are not considering alteration
    of the DTV signal strength standard for any purpose other than
    determining household eligibility to receive retransmitted distant
    network signals. We are initiating this inquiry in response to
    provisions of Section 204(b) of the Satellite Home Viewer Extension
    and Reauthorization Act of 2004 (SHVERA).[^310]

**BACKGROUND**

2.  Broadcast television stations have rights, through the Copyright
    Act[^311] and private contracts, to control the distribution of the
    national and local programming that they transmit.[^312] In 1988,
    Congress adopted the Satellite Home Viewer Act (SHVA) as an
    amendment to the Copyright Act in order to protect the
    broadcasters\' interests in their programming while simultaneously
    enabling satellite communications providers to provide broadcast
    programming to those satellite subscribers who are unable to obtain
    broadcast TV network programming over the air.[^313] Under the SHVA,
    those subscribers were generally considered to be \"unserved\" by
    local stations. Pursuant to the requirements of this statute, which
    linked the definition of "unserved households" to a
    Commission-defined measure of analog television signal strength
    known as "Grade B intensity,"[^314] the Commission adopted rules for
    determining whether a household is able to receive a television
    signal of this strength.[^315] In particular, the Commission adopted
    rules established a standardized method for measuring the strength
    of television signals at individual locations and endorsed a method
    for predicting the strength of such signals that could be used in
    place of actually taking measurements.[^316] For DTV stations, the
    counterparts to the Grade B signal intensity standards for analog
    television stations are the values set forth in Section 73.622(e) of
    the Commission's rules describing the DTV noise-limited service
    contour.[^317]

3.  In the Satellite Home Viewer Improvement Act of 1999 (SHVIA),[^318]
    Congress revised and extended the statutory provisions established
    by the 1988 SHVA. With regard to prediction of signal availability,
    the SHVIA added Section 339(c)(3) to the Communications Act of 1934,
    as amended (47 U.S.C. § 339(c)(3)), which provides that "\[T\]he
    Commission shall take all actions necessary, including any
    reconsideration, to develop and prescribe by rule a point-to-point
    predictive model for reliably and presumptively determining the
    ability of individual locations to receive signals in accordance
    with the signal intensity standard in effect under Section
    119(d)(10)(A) of title 17, United States Code."[^319] Section
    339(c)(3) further provides that "\[I\]n prescribing such a model,
    the Commission shall rely on the Individual Location Longley-Rice
    model set forth by the Federal Communications Commission in Docket
    No. 98-201, and ensure that such model takes into account terrain,
    building structures, and other land cover variations. The Commission
    shall establish procedures for the continued refinement in the
    application of the model by the use of additional data as it becomes
    available."[^320] The Individual Location Longley-Rice (ILLR) radio
    propagation model adopted by the Commission in CS Docket No. 98-201
    provides predictions of radio field strength at specific geographic
    points based on the elevation profile of terrain between the
    transmitter and each specific reception point.[^321] The SHVIA
    further required that the courts rely on the Individual Location
    Longley-Rice (ILLR) model established by the Commission for making
    presumptive determinations of whether a household is capable of
    receiving broadcast television signals of at least a certain
    threshold intensity.

4.  As indicated above, the threshold signal intensity level for
    determining eligibility to receive retransmitted distant analog
    network TV signals is the Grade B standard set forth in Section
    73.683(a) of the Commission's rules. The Grade B contour, originally
    established to describe the service area (or coverage contour) of
    analog TV stations, defines a geographic boundary curve on which the
    specified field strength is predicted to be exceeded 50 percent of
    the time at 50 percent of the locations.[^322] However, the values
    of the Grade B standard are set such that generally, if a household
    receives a television signal of Grade B intensity, it should receive
    an acceptable television picture at least 90 percent of the time.
    More specifically, the Grade B values represent field strengths that
    are strong enough, in the absence of man-made noise or interference
    from other stations, to provide at least 90 percent of the time a
    television picture that the mean observer would classify as
    "acceptable" using a receiving installation (antenna, transmission
    line, and receiver) typical of outlying or near-fringe areas.[^323]

5.  The SHVIA directed the Commission to evaluate all possible standards
    and factors for determining eligibility for retransmission of
    signals of network stations to determine whether it may be
    appropriate to recommend, in a report to Congress, modifying or
    replacing the Grade B intensity standard for the purpose of
    determining eligibility, and, if appropriate, to make a further
    recommendation relating to a standard for digital signals.[^324] In
    November 2000, the Commission issued its Report to Congress in this
    matter,[^325] recommending that the Grade B signal intensity
    standard and eight of the nine planning factors[^326] used in that
    model be retained as the basis for predicting whether a household is
    eligible to receive retransmitted distant TV network signals under
    SHVIA. The Commission also recommended modification of the remaining
    planning factor, *i.e.*, time fading, by replacing its existing
    fixed values with location-dependent values determined for the
    actual receiving locations using the ILLR prediction model. Finally,
    the Commission found that it would be premature to construct a
    distant network signal eligibility standard for DTV signals at that
    time. Therefore, the Commission recommended that establishment of a
    distant network signal eligibility standard for DTV signals be
    deferred until such time as more substantial DTV penetration is
    achieved and more experience is gained with DTV operation.

6.  The Commission has established a DTV Table of Allotments, which
    specifies channels for use by DTV stations in individual
    communities, using a procedure that closely replicates the service
    areas of the existing Grade B contours for analog TV stations.[^327]
    In particular, the Commission has defined DTV station service areas
    based on field strength levels that provide noise-limited service
    (the Grade B signal strength levels define noise-limited service for
    analog stations).[^328] DTV service areas are defined as the
    geographic area within a station's noise-limited field strength
    contour where its signal strength is expected to exceed that field
    strength level at 50 percent of the locations 90 percent of the time
    F(50,90).[^329] Within that contour, service is considered available
    at locations where a station's signal strength, as predicted using
    the terrain dependent Longley-Rice point-to-point propagation model,
    exceeds the noise-limited standards. The DTV noise-limited field
    strength standards are: channels 2-6 (low VHF)- 28 dBµ, channels
    7-13 (high VHF)- 36 dBµ, channels 14-69 (UHF)- 41 dBµ. These
    criteria presume that households will exert similar efforts to
    receive DTV broadcast stations as they have always been expected to
    exert to receive NTSC analog TV signals.

7.  In December 2004, Congress enacted the Satellite Home Viewer
    Extension and Reauthorization Act of 2004,[^330] which again amends
    the copyright laws[^331] and the Communications Act[^332] to further
    aid the competitiveness of satellite carriers and expand program
    offerings for satellite subscribers. Section 204 of the SHVERA
    provides that no later than one year after the date of enactment of
    this Act, the Commission is to complete an inquiry regarding
    whether, for purposes of identifying if a household is unserved by
    an adequate digital signal under Section 119(d)(10) of title 17 of
    the United States Code, the digital signal strength standard in
    Section 73.622(e)(1) of the Commission' rules or the testing
    procedures in Section 73.686(d) of those rules should be revised to
    take into account the types of antennas that are available to
    consumers.[^333] Section 204 of the SHVERA also requires the
    Commission to submit to the Congress a report containing the results
    of that study and recommendations, if any, for what changes should
    be made to Federal statutes or regulations. The SHVERA specifies
    that in conducting this inquiry the Commission is to consider the
    following six specific factors:[^334]

-   whether to account for the fact that an antenna can be mounted on a
    roof or placed in a home and can be fixed or capable of rotating;

-   whether Section 73.686(d) of title 47, Code of Federal Regulations,
    should be amended to create different procedures for determining if
    the requisite digital signal strength is present than for
    determining if the requisite analog signal strength is present;

-   whether a standard should be used other than the presence of a
    signal of a certain strength to ensure that a household can receive
    a high-quality picture using antennas of reasonable cost and ease of
    installation;

-   whether to develop a predictive methodology for determining whether
    a household is unserved by an adequate digital signal under section
    119(d)(10) of title 17, United States Code;

-   whether there is a wide variation in the ability of reasonably
    priced consumer digital television sets to receive over-the-air
    signals, such that at a given signal strength some may be able to
    display high-quality pictures while others cannot, whether such
    variation is related to the price of the television set, and whether
    such variation should be factored into setting a standard for
    determining whether a household is unserved by an adequate digital
    signal; and

-   whether to account for factors such as building loss, external
    interference sources, or undesired signals from both digital
    television and analog television stations using either the same or
    adjacent channels in nearby markets, foliage, and man-made clutter.

**DISCUSSION**

8.  As specified above, Congress has directed the Commission to take six
    specific considerations into account during the course of this
    Inquiry. Below, we deal with each of these areas in turn.

9.  *Antenna placement.* We request comment, analysis, and information
    on whether the procedures and standards for determining if any
    specific household should be deemed unserved by an adequate DTV
    network signal, should account for the fact that a receiving antenna
    can be mounted on a roof or placed in a home and can be fixed or
    capable of rotating. As an initial matter, we note that the
    effectiveness of receiving antennas is determined both by factors
    intrinsic to the specific antenna design and by external factors.
    More specifically, antennas are designed with varying amounts of
    antenna gain or directivity. The greater the gain of a receiving
    antenna, the greater is the antenna's ability to capture weak
    signals. However, there is a significant tradeoff when incorporating
    additional gain in an antenna design. That is, designing an antenna
    with greater gain requires that it also be designed to have a
    narrower beamwidth. Beamwidth, in turn, refers to the antenna's
    angle of orientation within which the gain occurs. The narrower the
    beamwidth of a receiving antenna, the more critical it is to
    accurately aim the antenna directly at the source of the signal of
    interest. The signal strength of a transmission that is received by
    an antenna's main lobe beamwidth will be stronger than if that
    transmission were received from a direction outside that main lobe.
    Other factors, such as antenna placement, also affect the ability of
    a household to receive an adequate DTV signal. For example, because
    structures located within the line of sight between the transmitter
    and the receiving antenna can block or weaken the strength of
    received signals, an outdoor antenna installation, such as upon a
    rooftop, will generally allow a stronger signal to be received by
    the antenna than will an indoor antenna installation. Thus,
    households in which the antenna is placed indoors will generally
    need an antenna with greater gain than will a household in which the
    antenna is placed outdoors.

10. As indicated above, the Commission defines digital television
    service areas on the basis of stations' noise-limited F(50,90)
    contour. Within this contour, the Longley-Rice model is used to
    predict areas where the DTV signal strength level exceeds the noise
    limited service level.[^335] Inherent in this method of predicting
    received signal strength levels are certain assumptions regarding
    the receiving system. For DTV, the Commission assumes that the
    receiving antenna is located outdoors at a height of 10 meters above
    ground.[^336] In addition, the Commission's procedures for
    evaluating DTV service areas set forth specific values for antenna
    gain that depend upon the specific DTV channel band, namely, 4 dB
    for low VHF, 6 dB for high VHF, and 10 dB for UHF and that the
    antenna be oriented in the direction which maximizes the values for
    field strength for the signal being measured.[^337]

11. With regard to the general characterization of antennas described
    above, we seek comment on whether there is a need to revise the
    standard by which adequate DTV network signals are deemed available
    to households in order to account for the facts that DTV antennas
    can be mounted on a roof or within a home and can be installed in a
    fixed position or in a mounting that allows them to be rotated.
    Specifically, we ask if the inherent assumptions regarding DTV
    antenna receiving systems should be modified or extended insofar as
    they relate to the proper determination of whether households are
    unserved by adequate broadcast DTV network signals and are thus
    eligible to receive distant DTV network signals from a satellite
    service provider. To properly evaluate this issue, we must have
    up-to-date reliable information regarding antennas that are
    available to the public. Therefore, commenting parties are requested
    to provide information on the types of antennas that are in use
    currently, or soon to be available for outdoor or indoor residential
    use. For these antennas, we request that relevant technical
    specifications such as size, gain, and beamwidth be provided. In
    addition, we request that commenting parties provide information on
    how these factors affect antenna cost and deployment. Further, we
    request information on the availability and cost of various devices
    that can be used to aim these antennas (*e.g*., rotors) toward DTV
    transmitters. In this regard, we request comment on how the addition
    of a rotor would affect the antenna size and thus the ability of
    consumers to mount the antenna indoors. We ask that commenters
    provide an evaluation of whether the use of an indoor antenna with
    or without a rotor would provide similar performance to that
    expected based on the Commission's assumed planning factors. If
    commenting parties believe that performance would differ
    significantly, we request that they provide detailed analytical
    information and explain how they believe our procedures should be
    modified.

12. *Signal strength measurement.* Congress has requested that the
    Commission consider whether Section 73.686(d) of the rules should be
    amended to specify procedures for determining if the requisite
    digital signal strength is present that are different from the
    procedures used for determining analog signal strength. Currently,
    Section 73.686(d) requires that field strength measurements be made
    using either a half--wave dipole antenna that is tuned to the
    station's visual carrier frequency or a gain antenna, provided that
    the antenna factor for the channel under test is known.[^338] In
    addition, the rules specify that the intermediate frequency (i.f.)
    bandwidth of the measuring instrumentation be at least 200 kilohertz
    but no more than 1,000 kilohertz. Measurements are to be taken in
    five locations, preferably close to the actual antenna or where one
    is likely to be mounted. In addition, the rules specify that the
    measurement antenna is to be raised to a height of 6.1 meters (20
    feet) above ground for one story structures and 9.1 meters (30 feet)
    above ground for two story or taller structures. Finally, because
    the current rule was written specifically to determine the field
    strength of analog TV signals, the procedures specify that the field
    strength measurement is to be made on the visual carrier.[^339] The
    measured values can then be compared to the field strength that
    defines the Grade B contour for the station in question to determine
    if the measured location is receiving a signal of sufficient
    intensity for analog television reception.

13. It is readily apparent that Section 73.686(d) needs some
    modification in order to be applied to digital TV signals. Unlike
    the analog signal, the digital signal does not contain a visual
    carrier. Therefore, at a minimum the rule must distinguish between
    analog and digital signals as it relates to the specific frequency
    on which to tune. We note that the digital TV signal does have a
    pilot signal that is used by the tuner to lock in on the desired
    received signal.[^340] Given this fundamental difference between the
    analog and digital signal, we ask commenting parties to provide
    information on the signal characteristics to which the measurement
    instrumentation should be tuned. For example, we believe that it
    makes most sense to tune the instrumentation either to the pilot
    signal or to the center of the channel. We also ask for comments on
    whether the i.f. bandwidth of the measurement equipment that is
    specified for analog TV signals is also appropriate for digital TV
    signals. Commenting parties who propose i.f. bandwidths that differ
    from the current specification should provide specific reasons for
    their proposals. We also request comment on the height that should
    be specified for the use of antenna equipment to measure outdoor
    signals, and on whether specific procedures should be created for
    measuring indoor signals. Further, if an indoor measurement
    procedure were adopted for determining signal availability, we seek
    comment on what criteria should be applied to determine whether an
    indoor or an outdoor measurement would be performed at a specific
    location. Finally, we seek comment on whether any other aspects of
    our measurement procedures need to be modified for the purpose of
    determining if households are unserved by an adequate digital TV
    signal. Commenting parties should provide specific technical
    justification for any aspects that they believe should be modified.

14. *Signal strength standard.* Currently, the rules specify that the
    field strength of the Grade B contour of an analog TV station be
    used as the standard for a determination of adequate signal
    strength. In the SHVERA, Congress requests that that Commission
    consider, for digital TV signals, whether a standard other than the
    presence of a signal of certain strength be used to ensure that a
    household can receive a high-quality picture using antennas of
    reasonable cost and ease of installation. We request comment on
    whether the current signal strength standard for noise-limited
    service should be used to define the availability of a DTV signal
    for determining whether a household is eligible to receive distant
    DTV signals from DBS services. In this connection, we also seek
    comment on whether there is a standard other than one based on
    signal strength that could be used to determine if a household is
    capable of receiving a high-quality digital TV picture. Commenting
    parties who propose a standard not based on signal strength should
    provide sufficient detail describing how their method would ensure
    reception of service and should explain how the proposed standard
    would be affected by the various technical characteristics the
    various specific antennas that are available or will soon be
    available for the residential market.

15. *Development of a predictive model.* The SHVERA requires that the
    Commission consider whether to develop a predictive methodology for
    determining whether a household is unserved by an adequate digital
    TV network signal under section 119(d)(10) of title 17, United
    States Code.[^341] As indicated above, the Commission has already
    established a predictive model that evaluates the signal strength of
    a particular digital TV station at a specific location. This model,
    described in OET Bulletin 69, uses the Longley-Rice radio
    propagation model to make predictions of radio field strength at
    specific geographic points based on the elevation profile of terrain
    between the transmitter and each specific reception point.[^342] The
    Commission, in accordance with SHVIA, has also implemented the use
    of a modified Longley-Rice model for identifying unserved households
    attempting to receive analog broadcast signals.[^343] We implemented
    the use of a modified Longley-Rice model in order to make the
    predictive model as accurate as possible by taking terrain features
    (such as hills), buildings, and land cover (such as forests) into
    account.[^344] We believe that the modified Longley-Rice is an
    accurate, practical, and readily available model for determining
    signal intensity at individual locations when used with analog
    signals. The modified Longley-Rice has several characteristics,
    discussed in detail below, which make it unique:

-   The time variability factor is 50% and the confidence variability
    factor is 50%;

-   The model is run in individual mode;

-   Terrain elevation is considered every 1/10 of a kilometer;

-   Receiving antenna height is assumed to be 20 feet above ground for
    one-story buildings and 30 feet above ground for buildings taller
    than one-story;

-   Land use and land cover (*e.g.*, vegetation and buildings) is
    accounted for;

-   Where error codes appear, they shall be ignored and the predicted
    value accepted or the result shall be tested with an on-site
    measurement;

-   Locations both within and beyond a station\'s Grade B contour shall
    be examined.[^345]

The Commission requests comment on whether the modified Longley-Rice,
with appropriate modifications, would accurately predict digital signal
coverage at a specific location, or whether there is some other
predictive model that would be more appropriate for this purpose.
Commenting parties who propose either specific modifications to the
modified Longley-Rice or alternative models should provide detailed
analysis as to how their proposed modifications will improve the
modified Longley-Rice's prediction characteristics and/or an explanation
of how the changes or alternatives more accurately model the available
signal level when accounting for terrain and possible signal
interference.

16. *DTV receiver threshold variation.* We request comment on whether
    there is a wide variation in the ability of reasonably priced
    consumer digital television sets to receive over-the-air signals, so
    that at given signal strengths some sets are able to display
    high-quality pictures while other sets cannot, and if so, whether
    this variation is related to the price of the television set. We
    also request comment on whether such variation should be factored
    into setting a standard for determining whether a household is
    unserved by an adequate DTV network signal. We are aware that there
    are a wide variety of digital TV sets available to consumers which
    are offered at various prices. We do not know, however, whether the
    difference in prices correlates to better receiver performance. We
    further note that many satellite reception set-top-boxes also
    contain DTV tuners, and seek comment on their reception
    capabilities. In the *Memorandum Opinion and Order on
    Reconsideration of the Sixth Report and Order,* the Commission noted
    that receiver performance involves trade-offs among many factors and
    that equipment manufacturers were in the best position to determine
    how best to meet consumer demand.[^346] We also noted that we would
    continue to monitor DTV receiver development, in particular with
    regard to indoor reception and multi-path signal rejection
    performance.[^347] On this point, we plan to conduct measurements on
    a variety of digital TV sets and factor the results of those
    measurements into the report that we will present to Congress as
    required by the SHVERA.

17. We seek information regarding the performance of digital receivers.
    Specifically, commenting parties should provide information
    regarding the sensitivity of various receivers and their
    interference rejection capability and should point out if there are
    different receiver signal processing algorithms for interpreting
    digital TV signals and their level of sophistication. This technical
    information should be accompanied by price data and analysis
    regarding the correlation between performance and price. Given that
    the Commission intends to independently conduct measurements on a
    sample of digital TV receivers, we ask if there are specific
    parameters that we should measure. If so, which parameters should we
    measure and what useful information will they provide? Finally, we
    ask if there are significant differences in digital receiver
    performance quality, should those differences be factored into the
    determination of whether a household is unserved by an adequate
    digital signal? Are consumers aware of any such differences so that
    they can take them into account when obtaining DTV equipment in
    order to assure themselves that they can receive signals at the
    levels available at their residences? Commenting parties who believe
    that digital receiver quality should be a factor are requested to
    provide detailed analysis and explain how receiver quality can be
    used in ascertaining whether a household is unserved. Finally, we
    ask commenters to discuss how any limitations in receivers can be
    mitigated by using higher performance antennas or auxiliary devices.

18. *DTV receiver interference.* A radio receiver's immunity to
    interference is dependent on a number of factors in its technical
    design and, in addition, on the characteristics of the signals it
    receives. These factors may be closely related and possibly
    interdependent, and a receiver's performance in one factor may often
    affect its performance in others. The factors determining receiver
    immunity performance generally include selectivity, sensitivity,
    dynamic range, automatic RF gain control, shielding, modulation
    method, and signal processing. Receiver selectivity is the ability
    to isolate and acquire the desired signal from among all of the
    undesired signals that may be present on other channels. Sensitivity
    is the measure of a receiver's ability to receive signals of low
    strength. Greater sensitivity means a receiver can pick up weaker
    signals.[^348] Dynamic range is the range of the highest and lowest
    received signal strength levels over which the receiver can
    satisfactorily operate. The upper side of a receiver's dynamic range
    determines how strong a received signal can be before failure due to
    overloading occurs. Automatic RF gain control allows a receiver to
    adjust the level of a received signal as it appears at the unit's
    signal processing and demodulation sections.

19. We request comment information on whether, and if so, how to account
    for factors such as signal attenuation from structural penetration,
    external interference sources (that is, undesired signals from both
    digital television and analog television stations using either the
    same or adjacent channels in nearby markets), foliage, and man-made
    clutter when determining whether a household is unserved by an
    adequate digital signal. We note that many factors can affect the
    reception of radio frequency signals and the ability of a receiver
    to resolve these signals and produce a picture. Most notably,
    interference from both co-channel and adjacent channel TV
    transmitters could cause interference to the desired signal.
    Selectivity is a central factor in the control of adjacent channel
    interference.[^349] However, we also note that different receiver
    designs may account for the differing abilities of receivers to
    reject greater or lesser amounts of interference. We request comment
    on the interference rejection capabilities of digital TV receivers
    and satellite set-top-boxes with built-in off-air receivers.

20. We also note that external forces can affect the signal that
    ultimately reaches a TV receiver. These include natural and man-made
    structures, such as structures, terrain, trees, *etc*., that lie
    between the transmitter and the receiver. These types of
    obstructions can affect a signal in various ways. First, they
    attenuate the signal so that the actual signal received is weaker
    than that predicted in the absence of any such obstructions. In this
    connection, we again note that indoor-mounted antennas will
    generally receive weaker signals than outdoor-mounted antennas.
    Second, obstructions can create multipath interference where signals
    that bounce off structures arrive at the receiver at different
    times. Multipath interference occurs when DTV signals arrive at the
    receiver via different paths. These signals, although they originate
    from the same transmitting source, are out of phase and can cause
    severe interference that can result in the complete loss of the
    digital service. Given these effects, we request comment on how well
    digital TV receivers and satellite set-top-boxes with built-in
    off-air receivers perform in these less than ideal conditions.
    Should such performance specifications be taken into account by the
    Commission in determining whether a household is unserved by an
    adequate digital signal? Commenting parties who propose that such
    factors be accounted for should provide detailed information
    regarding how these factors could be used and applied to individual
    situations. What additional factors, if any, should be included when
    determining the availability of a DTV signal at an individual
    location?

21. *Summary.* In sum, we request comment and information regarding how
    to determine whether any household is unserved by an adequate
    digital television network signal. This instant inquiry addresses
    the particular concerns that Congress has specified in section
    204(b) of the SHVERA, and the information gathered here will be used
    to prepare the requisite report to Congress. Commenting parties
    should be as specific as possible in providing information and
    describing how such information can be applied to the determination
    of household eligibility for reception of satellite providers'
    retransmissions of distant DTV network signals. Finally, commenting
    parties who believe that our applicable rules or Federal statutes
    should be modified are requested to state with particularity the
    rule and/or statutory modifications they advocate.

    **ORDERING CLAUSE**

22. Accordingly, IT IS ORDERED that, pursuant to Section 339(c) of the
    Communications Act of 1934, as amended by the Satellite Home Viewer
    Extension and Reauthorization Act of 2004, this Notice of Inquiry IS
    ADOPTED.

    FEDERAL COMMUNICATIONS COMMISSION

    Marlene H. Dortch

    Secretary

## APPENDIX E {#appendix-e .unnumbered}

COMMENTS AND REPLY COMMENTS

TO

NOTICE OF INQUIRY

[^1]: *See* The Satellite Home Viewer Extension and Reauthorization Act
    of 2004, Pub. L. No. 108-447, § 207, 118 Stat 2809, 3393 (2004)
    (codified at 47 U.S.C. § 339(c)). The SHVERA was enacted as title IX
    of the "Consolidated Appropriations Act, 2005." Hereinafter Section
    204(b) is cited as codified in 47 U.S.C. 339(c).

[^2]: [17 U.S.C. §
    119](http://web2.westlaw.com/find/default.wl?DB=1000546&DocName=17USCAS119&FindType=L&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08).

[^3]: See [17 U.S.C. §
    119(d)(10)(A)](http://web2.westlaw.com/find/default.wl?DB=1000546&DocName=17USCAS119&FindType=L&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08);
    [47 C.F.R. §
    73.683(a)](http://web2.westlaw.com/find/default.wl?DB=1000547&DocName=47CFRS73.683&FindType=L&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08).

[^4]: 47 C.F.R. § 73.683(a); *see also* 47 C.F.R. § 73.684.

[^5]: [47 CFR §
    73.622(e)](http://web2.westlaw.com/find/default.wl?DB=1000547&DocName=47CFRS73.622&FindType=L&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08);
    *see* also [47 CFR §
    73.625(b)](http://web2.westlaw.com/find/default.wl?DB=1000547&DocName=47CFRS73.625&FindType=L&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08)
    (determining coverage). As set forth in Section 73.622(e), a
    station's DTV service area is defined as the area within its
    noise-limited contour where its signal strength is predicted to
    exceed the noise-limited service level.

[^6]: 47 U.S.C. § 119(d)(10); 47 C.F.R. § 73.622(e)(1); 47 C.F.R. §
    73.686(d).

[^7]: Satellite Delivery of Network Signals to Unserved Households for
    Purposes of the Satellite Home Viewer Act, CS Docket No. 98-201,
    *Report and Order*[, 14 FCC Rcd 2654, 2655 at ¶ 2
    (1999)](http://web2.westlaw.com/find/default.wl?DB=4493&SerialNum=1999285464&FindType=Y&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08)
    (*SHVA Report and Order*); *Order on Reconsideration*[, 14 FCC Rcd
    17373
    (1999)](http://web2.westlaw.com/find/default.wl?rs=WLW5.09&tf=757&tc=7&fn=_top&sv=Split&mt=Westlaw&vr=2.0&serialnum=1999289330&rp=/find/default.wl).

[^8]: [*SHVA Report and Order*, 14 FCC Rcd at 2656 ¶
    4](http://web2.westlaw.com/find/default.wl?DB=4493&SerialNum=1999285464&FindType=Y&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08).

[^9]: [*SHVA Report and Order*, 14 FCC Rcd at 2657 ¶
    8](http://web2.westlaw.com/find/default.wl?DB=4493&SerialNum=1999285464&FindType=Y&AP=&mt=Westlaw&fn=_top&sv=Split&vr=2.0&rs=WLW5.08).

[^10]: *See* Consolidated Appropriations Act for 2000, Pub. L. 106-113,
    § 1000(9), 113 Stat. 1501 (enacting S. 1948, including the Satellite
    Home Viewer Improvement Act of 1999, Title I of the Intellectual
    Property and Communications Omnibus Reform Act of 1999, relating to
    copyright licensing and carriage of broadcast signals by satellite
    carriers, codified in scattered sections of 17 and 47 U.S.C.).
    Section 1008(a) of SHVIA added, *inter alia,* new Section 339
    ("Carriage of Distant Television Stations by Satellite Carriers") to
    the Communications Act of 1934, [47 U.S.C. §
    151](http://web2.westlaw.com/find/default.wl?mt=Westlaw&fn=_top&sv=Split&cite=47usc151&rp=/find/default.wl&vr=2.0&rs=WLW5.09)
    *et seq*.

[^11]: *See also* 47 C.F.R. § 73.683(a) (Grade B field strength contours
    for channels 2-6, 7-13, and 14-69).

[^12]: *See* In the Matter of Establishment of an Improved Model for
    Predicting the Broadcast Television Field Strength Received at
    Individual Locations, *First Report and Order* in ET Docket No.
    00-11 (*ILLR First Report and Order*), 15 FCC Rcd 12118 (2000);
    recon. *Memorandum Opinion and Order* in ET Docket No. 00-11, 19 FCC
    Rcd 9963 (2004); appeal pending, EchoStar L.L.C. v. FCC & USA, No.
    04-1304 (D.C. Circuit).

[^13]: *See* 47 U.S.C. § 339(c). *See also* 17 U.S.C. § 119(a)(2)(b) and
    (d)(10). Section 339(c) sets forth the circumstances in which Direct
    Broadcast Satellite (DBS) subscribers are eligible to receive
    retransmission of distant network signals. *See also* 47 U.S.C.
    339(c)(1) *as amended by* the SHVERA.

[^14]: *See* *Report to Congress*, *In the Matter of Technical Standards
    for Determining Eligibility for Satellite Delivered Network Signals
    Pursuant to the Satellite Home Viewer Improvement Act*, 15 FCC Rcd
    24321 (2000). The eight planning factors recommended for retention
    were: thermal noise, transmission line loss, receiving antenna gain,
    dipole factor, terrain factor, urban noise, signal-to-noise ratio,
    and urban noise. The development of the Grade B signal intensity
    standard and its use in connection with the authorization of analog
    television stations and the determination of stations' service areas
    and contours is also discussed in greater detail in the *SHVIA
    Report*.

[^15]: *Id.*

[^16]: [47 U.S.C. §
    339](http://web2.westlaw.com/find/default.wl?mt=Westlaw&fn=_top&sv=Split&cite=47usc339&rp=/find/default.wl&vr=2.0&rs=WLW5.09).

[^17]: [47 U.S.C. §
    339(a)(2)(D)(vi)](http://web2.westlaw.com/find/default.wl?mt=Westlaw&fn=_top&sv=Split&cite=47usc339&rp=/find/default.wl&vr=2.0&rs=WLW5.09).

[^18]: *See* Section 73.622(e)(1) of the Commission's Rules, 47 C.F.R. §
    73.622(e)(1). The F(50, 90) contour describes the outer edge of a
    geographic area in which a transmitter's signal strength is
    predicted to exceed the field strength standard at 50 percent of the
    locations 90 percent of the time.

[^19]: *See* Section 73.622(e) (1) and (2) of the Commission's Rules, 47
    C.F.R. § 73.622(e) (1), (2). Guidance for evaluating digital
    television station coverage areas using the Longley-Rice methodology
    is provided in OET Bulletin No. 69, *see* OET Bulletin No. 69,
    "Longley-Rice Methodology for Evaluating TV Coverage and
    Interference" (July 2, 1997). OET Bulletin No. 69 is available on
    the Commission's website at
    <http://www.fcc.gov/oet/info/documents/bulletins/>.

[^20]:
    > 47 U.S.C. § 339(c)(1). The report is to be submitted to the
    > Committee on Energy and Commerce of the House of Representatives
    > and to the Committee on Commerce, Science, and Transportation of
    > the Senate. The report is to contain recommendations, if any, as
    > to what changes should be made to Federal statues or regulations.
    > See 47 U.S.C. § 339(c)(1)(C).

[^21]: 47 U.S.C. 339(c)(1)(B)(i)-(vi), *as amended by* Section 204(b) of
    the SHVERA. The complete text of the new Section 339(c)(1) is set
    forth in Appendix A.

[^22]:
    > [In the Matter Of Technical Standards For Determining Eligibility
    > For Satellite-Delivered Network Signals Pursuant To The Satellite
    > Home Viewer Extension and Reauthorization Act, ET Docket No.
    > 05-182, *Notice of Inquiry (Inquiry)*, 20 FCC Rcd. 9349
    > (2005).](http://web2.westlaw.com/find/default.wl?rs=WLW5.09&findjuris=00001&cite=20+FCC+Rcd.+9349&fn=_top&mt=Westlaw&vr=2.0&sv=Split&rp=/find/default.wl)

[^23]:
    > The criteria for eligibility to receive a distant network signal
    > from a DBS service also include factors in addition to the ability
    > of a household to receive that network signal over-the-air from a
    > local TV station, *see* Section 339 of the Communications Act, 47
    > U.S.C. § 339.

[^24]:
    > *See* Television Broadcast Service, *Third Notice of Further
    > Proposed Rule Making*, Appendix B, 16 Fed. Reg. 3072, 3080 (April
    > 7, 1951), adopted in Amendment of Section 3.606 of the
    > Commission's Rules and Regulations and Amendment of the
    > Commission's Rules, Regulations, and Engineering Standards
    > Concerning the Television Broadcast Service in the Band 470 to 890
    > MHz for Television Broadcasting, *Sixth Report and Order*, 41 FCC
    > 148 (1952); *see also* Advanced Television Systems and Their
    > Impact upon the Existing Television Broadcast Service, *Sixth
    > Report and Order* in MM Docket No. 87-268, 12 FCC Rcd 14588 (1997)
    > (*DTV Sixth Report and Order*), at ¶¶183-196.

[^25]:
    > Guidance for evaluating DTV coverage areas using the Longley-Rice
    > methodology is provided in *OET Bulletin No. 69*, which is
    > available through the Internet at the Commission's website,
    > <http://www.fcc.gov/oet/info/documents/bulletins/>.

[^26]:
    > *See* *DTV Sixth Report and Order, supra* note Error: Reference
    > source not found, at ¶¶ 29-33 and Appendix B.

[^27]: *See* *DTV Sixth Report and Order*, *supra* note Error: Reference
    source not found, at Appendix A.

[^28]: The Association for Maximum Service Television, Inc. (MSTV)
    comments at 2 (Commission should reaffirm the DTV signal strength
    standards for determining DTV service availability and for
    identifying underserved households pursuant to SHVERA); Consumer
    Electronics Association (CEA) comments at 3 (although antenna type
    and placement is a critical factor in DTV reception, it should not
    be considered in determining household eligibility for distant DTV
    network signal reception; instead, such eligibility should be
    determined based on the failure of a signal of at least a given
    field strength to be present at a specified height above the
    location); NAB comments, *passim;* and Network Affiliates comments,
    *passim.*

[^29]: NAB comments at 16.

[^30]: *Id.* at 14 and 18-20. NAB points out that, in comparison to
    outdoor antennas, indoor antennas do not perform as well at
    receiving over-the-air TV signals, have lower gain, are placed in
    inferior locations for over-the-air reception, are typically
    nondirectional, and are affected by the movement of people within
    the room. *Id.* at 16-17.

[^31]: *Id.* at 18-19.

[^32]: Id. at 17.

[^33]: *Id.* at 18.

[^34]: *See* CEA comments at 2.

[^35]: Network Affiliates comments at 13-38.

[^36]: *Id*. at 15-33.

[^37]: *Id.* at 34.

[^38]: *Id.* at 35.

[^39]: MSTV comments at 2; NAB comments at 16-25; Network Affiliates
    comments at 13-15 and 37-38.

[^40]: CEA comments at 3.

[^41]: EchoStar comments at 4 and 6*;* Robinson Telephone comments,
    *passim*; and Viamorph, Inc. comments, *passim* (predictive model
    should include methods to account for variations in antenna
    performance, including receiving antenna characteristics and
    detailed geographical, botanical, atmospheric and other data;
    Viamorph states that it is introducing a new "digital smart antenna"
    technology into the consumer marketplace).

[^42]: EchoStar comments at 4 and 6.

[^43]: *See* OET Bulletin 69, "Longley-Rice Methodology for Evaluating
    TV Coverage and Interference" (February 6, 2004), at 6 Table 4; *see
    also* 47 C.F.R. § 73.699.

[^44]: *Id.* at 9.

[^45]: NAB comments at 18-19.

[^46]: NAB comments, Attachment 1 (engineering statement of MSW) at 3.

[^47]: Network Affiliates comments at 34.

[^48]: *Id.* at 34-35.

[^49]: EchoStar comments at 6-8; Robinson Telephone comments, *passim.*

[^50]: Network Affiliates comments at 29-32; NAB comments at 35-43; MSTV
    comments, Attachment (Engineering Statement of Louis Robert du
    Treil, Jr. of dLR at 5-6; *see also* ATI Technologies comments,
    *passim.*

[^51]: Network Affiliates comments at 34.

[^52]: *Id.*

[^53]: *Id.* at 35.

[^54]: Network Affiliates comments, Appendix (Engineering Statement of
    Jules Cohen) at 2.

[^55]: Network Affiliates comments at 18 and 35; NAB comments at 27-28.

[^56]: Network Affiliates comments at 18. The Network Affiliates further
    note that the Electronics Technicians Association, a group whose
    members install and work in the field with antennas on a day-to-day
    basis, stated in its comments in the Commission's proceeding in CS
    Docket No. 98-201 that the eight-bay and four-bay bowtie-with-screen
    antennas are the conventional UHF antennas for fringe rural areas.
    *Id.* (citing CS Docket No. 98-201, Electronics Technicians
    Association, International, Inc. (ETA) Comments at 23).

[^57]: *Id.* at 18-19.

[^58]: *Id.* at 19; see also MSTV comments, Attachment (Engineering
    Statement of dLR) at 6 (Table 2); Viamorph comments at 1-2.

[^59]: Network Affiliates comments at 19.

[^60]: *Id.* at 19 n.51.

[^61]: *Id.* at 19.

[^62]: *Id.* at 19-20.

[^63]: *Id.* at 20.

[^64]: *Id.* at 20 n.53 (pricing information for Channel Master No. 3610
    not available).

[^65]: NAB comments at 22.

[^66]: *Id.* at 22 and Attachment 1 (Engineering Statement of MSW) at
    16.

[^67]: Network Affiliates comments at 20.

[^68]: *Id.* at 20, n.54.

[^69]: *Id.* at 20-21 and n.55.

[^70]: *Id.* at 21.

[^71]: *Id.* at 21-22.

[^72]: *Id.* at 22 (quoting *ATSC Recommended Practice: Receiver
    Performance Guidelines*, Doc A/74 (June 18, 2004) at 24).

[^73]: *Id.* at 22-23.

[^74]: *Id.* at 23.

[^75]: *Id.* at 23-24; NAB comments at 16-23.

[^76]: NAB comments, Attachment 1 (Engineering Statement of MSW) at
    17-18; see also Network Affiliates comments at 25-26 and Appendix
    (Engineering Statement of Jules Cohen) at 3.

[^77]: Network Affiliates comments at 25 and n.70.

[^78]: *Id.* at 25 and n.71.

[^79]: *Id.* at 25-26.

[^80]: NAB comments at 23, and Attachment 1 (Engineering Statement of
    MSW) at 18.

[^81]: Network Affiliates comments, Appendix (Engineering Statement of
    Jules Cohen) at 3.

[^82]: *Id.*

[^83]: EchoStar comments at 7-8.

[^84]: *Id.,* Attachment A (Engineering Statement of H&E) at 3 (worst
    case scenarios are 10, 12 and 14 dB for low VHF, high VHF and UHF,
    respectively). H&E does not provide a value for average signal loss
    from mispointing,

[^85]: *Id.*

[^86]: EchoStar comments at 7-8.

[^87]: MSTV comments at 2 and Attachment (Engineering Statement of dLR)
    at 9; Network Affiliates comments at 34-35; NAB comments at 19-20
    and Att.1 (Engineering Statement of MSW) at 13-15.

[^88]: Network Affiliates comments at 27.

[^89]: *Id.* (quoting CS Docket No. 98-201, ETA Comments, *supra* note
    Error: Reference source not found, at 6).

[^90]: NAB comments at 19-20.

[^91]: *See* NAB comments at 25-26.

[^92]: *Id.* at 20.

[^93]: MSTV comments, Attachment (Engineering Statement of dLR) at 9;
    Network Affiliates comments at 27 and Appendix (Engineering
    Statement of Jules Cohen), Exhibit 3 (Rotors).

[^94]: NAB comments at 20; Network Affiliates comments at 27-28.

[^95]: Viamorph comments at 2-4. Viamorph indicates that its DiSA^TM^
    antenna is amenable to indoor and outdoor mounting, with the current
    standard model consisting of a flat, rectangular package about 60 cm
    by 40 cm (approximately 23 inches by 16 inches) on a side and less
    than two inches (*i.e.,* about 5 cm) thick.

[^96]: EchoStar comments at 6. EchoStar (Comments, Attachment A
    (Engineering Statement of H&E) at 4 and 14-15) points to a study
    published by the Institute for Telecommunication Sciences in 1979
    (FizGerrel, R.G.. *et al.*, "Television Receiving Antenna System
    Component Measurements," NTIA Report 79-22, June 1979) and to more
    recent data published by Dielectric Communications (Kerry W. Cozad,
    "Measured Performance Parameters for Receive Antennas Used in DTV
    Reception," *Proceedings of the NAB Engineering Conference*, 2005
    (Cozad Study)).

[^97]: EchoStar comments at 6-7. H&E indicates that studies show that
    indoor antennas typically provide about 8 dB, 10 dB, and 9 dB less
    gain than outdoor antennas in the low VHF, high VHF, and UHF bands,
    respectively. EchoStar comments, Att. A (Engineering Statement of
    H&E) at 4.

[^98]: EchoStar comments at 7.

[^99]: EchoStar comments at 6-7.

[^100]: Robinson Telephone Company comments at 2.

[^101]: NAB comments at 16-17.

[^102]: *Id.* at 17.

[^103]: *Id*.

[^104]: *Id.* at 17 and Att.1 (Engineering Statement of MSW) at 11-12.

[^105]: *Id.* at 17 and Att.1 (Engineering Statement of MSW) at 11; see
    also *id.* at Att. 2 (Cozad Study, *supra* note Error: Reference
    source not found)).

[^106]: Network Affiliates reply comments at 6.

[^107]: *Id,* at 16-19; Network Affiliates comments at 34, 39-40.

[^108]: NAB reply comments at 3-4 and Att. (Reply Engineering Statement
    of MSW) at 5-6.

[^109]: *Id.* at 4.

[^110]: *Id.* at 18-19 and Att. 1 (Engineering Statement of MSW) at 3-4.

[^111]: Network Affiliates comments at v, 13-15.

[^112]: A 30 dB power increase would mean that a station operating at 1
    MW DTV power would need to operate with 1000 MW, an enormously high
    power level that is not achievable by currently available TV
    transmitters.

[^113]: There are other receiver performance factors such as
    selectivity, overload, and shielding against signal ingress that
    affect its ability to reject unwanted signals. These factors are
    less important in the context of this Report.

[^114]: All electronic devices generate some amount of internal noise,
    the level of which depends on their design and the components used
    in their construction.

[^115]: With digital television service, if a receiver's adaptive
    equalizer is unable to handle multipath the result is no service.

[^116]: Digital television receivers are typically designed to provide
    picture quality at one of several maximum quality levels: standard
    definition (similar to analog 480i service), enhanced definition
    (480p or 640p), or high definition (720p or 1080i). The price of
    receivers generally increases with higher picture quality
    capability.

[^117]: MSTV comments, Att. (Engineering Statement of dLR) at 8.

[^118]: NAB comments at 22, Att. 1 (Engineering Statement of MSW) at 17.

[^119]: MSTV comments, Att. (Engineering Statement of dLR) at 8 and n.3
    (citing Bouchard, Pierre, *et al.*, "Digital Television Test Results
    -- Phase I," Communications Research Centre (Ottawa, Canada), *CRC
    Report No. CRC-RP-2000-11*, November 2000).

[^120]: The worst performing receiver in the Bouchard study was the
    oldest measured unit.

[^121]: MSTV comments, Att. (Engineering Statement of dLR) at 8-9 and
    n.4 (citing "Results of the Laboratory Evaluation of Zenith 5^th^
    Generation VSB Television Receiver for Terrestrial Broadcasting,"
    Report Version 1.1, Communications Research Centre Canada, September
    2003).

[^122]: EchoStar comments at 4 and Att. A (Engineering Statement of H&E)
    at 12-13.

[^123]: EchoStar comments, Att. A (Engineering Statement of H&E) at
    12-13. Three of the receivers in the H&E study were obtained from
    retailers in May 2005, the fourth was an older model purchased in
    2000, and the fifth was a professional ATSC demodulator.

[^124]: ATI reply comments at 2.

[^125]: EchoStar comments at 5 and Att. A (Engineering Statement of H&E)
    at 8-9.

[^126]: EchoStar comments, Att. A (Engineering Statement of H&E) at 12
    and nn.37-38.(citing Charles Einhoff, "DTV Receiver Performance in
    the Real World," *Proceedings of the NAB Broadcast Engineering
    Conference*, 2000, and Bernard Caron, *et al.*, "ATSC 8-VSB Receiver
    Performance Comparison," *Proceedings of the NAB Broadcast
    Engineering Conference*, 2000).

[^127]: MSTV comments, Att. (Engineering Statement of dLR) at 8-9; NAB
    comments at 39-40 and Att. 1 (Engineering Statement of MSW) at
    35-43; Network Affiliates comments at 29-31.

[^128]: MSTV comments, Att. (Engineering Statement of dLR) at 9 and n.5
    (citing Tim Laud, *et al.*, "Performance of 5^th^ Generation 8-VSB
    Receivers," IEEE Transactions of Consumer Electronics, Vol. 50, No.
    4, Nov. 2004, and Yiyan Wu, *et al.*, "An ATSC DTV Receiver With
    Improved Robustness to Multipath and Distributed Transmission
    Environments," IEEE Transactions on Broadcasting, Vol. 50, No. 1,
    March 2004).

[^129]: ATI comments at 3-5. ATI also indicates that in cooperation with
    its customers in all affected industries it has developed a robust
    test procedure and grading system for evaluating multipath based on
    the A/74 field ensembles. See *id.* at 5-7 and Att. B (ATI White
    Paper, June 2005).

[^130]: Network Affiliates comments at 30.

[^131]: *Id.* at 37.

[^132]: *Id.* (citing *ATSC Recommended Practice: Receiver Performance
    Guidelines,* Doc. A/74 (June 18, 2004) at 24).

[^133]: ATI comments at 7-9.

[^134]: *Id.;* Network Affiliates comments at 35-37.

[^135]: ATI comments at 7-9.

[^136]: CEA comments at 4-5.

[^137]: Network Affiliates comments at 36.

[^138]: *See* "Tests of ATSC 8-VSB Reception Performance of Consumer
    Digital Television Receivers Available in 2005," OET Report FCC/OET
    TR 05-1017, Stephen R. Martin, FCC Laboratory Division, November 2,
    2005 (*FCC Study*). A copy of this report is attached hereto as
    Appendix C.

[^139]: See "*ATSC Recommended Practice: Receiver Performance
    Guidelines*," ATSC Doc. A/74, Advanced Television System Committee,
    17 June 2004. A multipath capture is a recording of the multipath
    signal pattern that is present at a given location. These are also
    termed ensembles because a set of specific reflections, *i.e.*,
    ensemble, will be present at any given location. Three of the 50
    recommended captures were excluded from our Laboratory testing
    because they contain no video content and therefore require
    specially instrumented receivers for testing.

[^140]: Receiver noise figures were determined by inference from this
    equation using the thermal noise figure common to all receivers and
    the measured S/N for each receiver.

[^141]: The absolute measurement accuracy of the vector signal analyzer
    on the amplitude range that was used for the measurements was +/-
    1.5 dB maximum and +/- 0.5 dB typical.

[^142]: The letter/number designations indicate the individual receivers
    tested.

[^143]: The span does not match the difference between worst and best
    performing receivers due to the rounding of results to the nearest
    0.1 dB.

[^144]: In this testing, each receiver was subjected to exactly the same
    multipath conditions for each capture (the captures are recordings).
    The lower portion of each bar represents the number of captures that
    played without a visible error during a single loop, *i.e.*,
    recording of the capture (a recording of multipath capture is played
    continuously in a loop). The upper portion of each bar adds the
    captures that played with no more than two visible errors during a
    single loop of capture. This chart also includes a bar on the right
    showing the results for the reference receiver used the FCC field
    tests in 2000, *see* "A Study of ATSC (8-VSB DTV Coverage in
    Washington, DC, and Generational Changes in DTV Receiver
    Performance," (Interim Report) OET Report, FCC/OET TRB-00-2 (2001
    FCC Field Test Receiver Study), William H. Inglis and David L.
    Means, February 2, 2001.

[^145]: It should be noted that some of the RF captures may contain
    recording flaws that could prevent error-free demodulation
    regardless of how advanced the demodulator technology may be, *see
    FCC Study, supra* note Error: Reference source not found, at 6-3.
    For example, four of the captures for which no tested receiver
    achieved demodulation free of visual errors were identified by the
    ATSC as having possible non-linearities caused by high-level
    adjacent channels overdriving the recording system. These or other
    potential flaws may preclude a 100% success rate on the 47 captures
    from ever being achieved by any demodulator. Thus, the FCC Study
    views the multipath performance data based on these captures to be
    useful for purposes of comparing receivers, but not as an absolute
    measure of performance.

[^146]: We emphasize that the tested multipath conditions are those
    known to be most difficult and are not typical of conditions that
    most households will encounter in receiving digital television
    service.

[^147]: Since an automatic gain control would be expected to provide
    sufficient gain to amplify the input signal - whatever its level -
    to a fixed level for processing in the demodulator, one would expect
    that the tap noise generated after this variable amplification would
    be at a fixed level relative to the DTV signal rather than at a
    fixed level relative to the antenna input - hence the impact would
    appear as a degradation to required S/N (white noise threshold)
    rather than as an increase in noise figure.

[^148]: The "coverage sites" measured in the *2001 Field Test Receiver
    Study* were selected without regard to multipath conditions. *See*
    *2001 Field Test Receiver Study*, *supra* note Error: Reference
    source not found.

[^149]: *See* *e.g.*, Laud, Tim, Aitken, Mark; Bretl, Wayne; and Kwak,
    K. Y., "Performance of 5th Generation 8-VSB Receivers", IEEE
    Transactions on Consumer Electronics, Vol. 50, No. 4, November 2004,
    which states that the fifth generation receiver includes "techniques
    for reduced noise enhancement.

[^150]: *See* FCC Study at 8-4.

[^151]: MSTV comments, Att. (Engineering Statement of dLR) at 3-4;
    Network Affiliates comments at 15.

[^152]: EchoStar comments at 4-5 and Att. A (Engineering Statement of
    H&E) at 9-11.

[^153]: EchoStar comments, Att. A (Engineering Statement of H&E) at 10
    and n.29 (citing A.D. Spaulding and R.T. Disney, "Man-made radio
    noise, part 1: estimates for business, residential, and rural
    areas," NTIA Office of Telecommunications Report OT 74-38, June
    1974).

[^154]: *Id.* at 10 and n.30 (citing Robert J. Atchaz and Roger A.
    Dalke, "Man-Made Noise Power Measurements at VHF and UHF
    Frequencies," NTIA Report No. 02-390, December 2001 (2001 NTIA
    study)).

[^155]: Network Affiliates reply comments at 8-10.

[^156]: *Id.* at 8 and n.25 (citing 2001 NTIA study, *supra* note Error:
    Reference source not found, at 25).

[^157]: *Id.* at 9 and n.27 (citing R.J. Achatz *et al*, "Man-Made Noise
    in the 136 to 138 MHz VHF Meteorological Satellite Band," NTIA
    Report 98-355 (Sept. 1998), at 31).

[^158]: NAB reply comments at 11 (citing 2001 NTIA study, *supra* note
    Error: Reference source not found, at 25).

[^159]: *Id.* at 12.

[^160]: MSTV comments, Att. (Engineering Statement of dLR) at 4 and 7-8;
    Network Affiliates comments at 31 and App. (Engineering Statement of
    Jules Cohen) at 4; and NAB comments at 23-24 and Att. 1 (Engineering
    Statement of MSW) at 18-19.

[^161]: Network Affiliates comments at 31 and n.88 (citing *Draft
    Revision of* Recommendation *ITU-R BT.1368-4* at Table 13).

[^162]: MSTV comments, Att. (Engineering Statement of dLR) at 7-8 (Table
    4).

[^163]: EchoStar reply comments at 14-15 and Att. A (Engineering Reply
    Statement of H&E) at 2-3.

[^164]: NAB reply comments, Att. (Engineering Reply Statement of MSW)
    14-15.

[^165]: *See* D. Schnelle and R.E. Wetmore, "Evaluation of Antenna and
    Receiver Mismatch Effects on DTV Reception,\" *48 IEEE Trans. on
    Broadcasting* 365, 369 (Dec. 2002).

[^166]: In the case of analog TV service, the planning factors include
    adjustments to the time variability factors in order to provide for
    service at 50% of locations 90% of the time. Those values add 6 dB
    at low VHF, 5 dB at high VHF, and 4 dB at UHF to the F(50,50)
    contour values to define the analog Grade B contour values. The
    analog location variability factors were set at zero. This
    adjustment was not needed for DTV signals as the signal strength
    standards were based on the F(50,90) levels of signal availability
    rather than the F(50,50) levels.

[^167]: EchoStar comments at 9 and Att. A (Engineering Statement of H&E)
    at 6-7.

[^168]: NAB reply comments at 7-8 and Att. (Reply Engineering Statement
    of MSW) at 10; Network Affiliates reply comments at 7-8.

[^169]: NAB reply comments, Att. (Reply Engineering Statement of MSW) at
    9;

[^170]: The FCC propagation curves are set forth in Section 73.699 of
    the Commission's rules, 47 C.F.R. § 73.699.

[^171]: Network Affiliates comments at 16.

[^172]: *See* OET Bulletin No. 69 at 3-4.

[^173]: We note that Jules Cohen, the consulting engineer for Network
    Affiliates, appears to agree with this conclusion. *See* Network
    Affiliates comments, Appendix (Engineering Statement of Jules Cohen)
    at 5 ("in light of an absence of need to change other \[planning
    factors\]," the dipole factor is not proposed to be changed).

[^174]: Greater sensitivity can also result in reception of unwanted
    signals at low levels that then must be eliminated or attenuated by
    the selectivity characteristics of the receiver.

[^175]: *Inquiry, supra* note Error: Reference source not found, at ¶
    19.

[^176]: There are several ways to describe the selectivity of a radio
    receiver. One way is to simply give the bandwidth of the receiver
    over which its response level is within 3 dB of its response level
    at the center frequency of the desired signal. This measure is often
    termed the "bandwidth over the -3db points." This bandwidth,
    however, is not necessarily a good means of determining how well the
    receiver will reject unwanted frequencies. Consequently, it is
    common to give the receiver bandwidth at two levels of attenuation;
    for example, -6dB and -60 dB. The ratio of these two bandwidths is
    called the shape factor. Ideally, the two bandwidths would be equal
    and the shape factor would be one. However, this value is very
    difficult to achieve in a practical circuit.

[^177]: *See* Interference Immunity Performance Specifications for Radio
    Receivers; Review of the Commission's Rules and Policies Affecting
    the Conversion to Digital Television, *Notice of Inquiry* in ET
    Docket No. 03-65 and MM Docket No. 00-39, 18 FCC Rcd 6039 (2003).

[^178]: *See* "A/74 Recommended Practice: Receiver Performance
    Guidelines," Advanced Television Systems Committee, Inc., June 18,
    2004.

[^179]: H&E citing Oded Bendov, "Interference to DTV Reception by First
    Adjacent Channels," *IEEE Trans. on Broadcasting*, Vol. 51, No. 1,
    March 2005 and Charles W. Rhodes, "Interference between Television
    Signals Due to Intermodulation in Receiver Front-Ends," *IEEE Trans.
    on Broadcasting*, Vol. 51, No. 1, March 2005.

[^180]: *See* Review of the Commission's Rules and Policies Affecting
    the Conversion to Digital Television, *Report and Order and Further
    Notice of Proposed Rule Making*, 16 FCC Rcd 5946 (2001). That
    decision also discusses the Commission's approach to regulation of
    television receiver performance.

[^181]: *See* CEA comments at 3-4.

[^182]: *See* 47 C.F.R. § 73.686(d); *see* also, *SHVA Report and
    Order,* 14 FCC Rcd 2654 at ¶ 8.

[^183]: 47 U.S.C. 339(c)(1)(B)(ii), *as amended by* Section 204(b) of
    the SHVERA.

[^184]: *See* 47 CFR 73.686(d)(1)(i).

[^185]: *See* 47 C.F.R. § 73.686(d)(2)(i).

[^186]: *See* 47 C.F.R. § 73.686(d)(1)(ii).

[^187]: *See* 47 C.F.R. § 73.686(d)(2)(iii).

[^188]: *See* 47 C.F.R. §§ 73.686(d)(1)(i) and 73.686(d)(2)(i).

[^189]: *Inquiry, supra* note Error: Reference source not found, at ¶
    13.

[^190]: *Id.*

[^191]: The pilot signal is located 0.31 MHz inside the lower band edge
    of the DTV channel and has a power level that is 3 dB lower than the
    average power of the DTV signal.

[^192]: 47 CFR § 73.622(e); *see also* 47 CFR § 73.625(b) (determining
    coverage).

[^193]: *Inquiry, supra* note Error: Reference source not found, at ¶
    20.

[^194]: NAB comments at 25; Network Affiliates comments at 38.

[^195]: NAB comments at 26.

[^196]: NAB comments at 26-27; Network Affiliates comments at 38-39.

[^197]: *E.g.,* NAB comments, Att. 1 (Engineering Statement of MSW) at
    21.

[^198]: *Id.* at 20-21.

[^199]: *Id.* at 38.

[^200]: NAB comments at 27; Network Affiliates comments at 39.

[^201]: EchoStar comments at 6-7.

[^202]: *Id.* at 7.

[^203]: NAB comments at 27.

[^204]: NAB comments at 27 and Att. 1 (Engineering Statement of MSW) at
    22.

[^205]: Network Affiliates comments at 39-40.

[^206]: NAB reply comments at 3.

[^207]: EchoStar comments at 7.

[^208]: EchoStar comments at 8.

[^209]: *Id.,* Att. 1 (Engineering Statement of H&E) at 4.

[^210]: NAB reply comments at 4.

[^211]: Network Affiliates reply comments at 15; NAB reply comments at
    6.

[^212]: NAB reply comments at 5.

[^213]: *Id.*

[^214]: EchoStar comments at 5.

[^215]: *Id.*.

[^216]: White noise enhancement is the increased noise added to the
    system by the equalizer as it attempts to compensate for multipath.
    EchoStar comments, Att. A (Engineering Statement of H&E) at 8-9.

[^217]: NAB reply comments at 10-11; Network Affiliates reply comments
    at 10.

[^218]: EchoStar comments at 8. It states that a correction factor can
    be derived from the F(50. 50) and F(50. 90) curves by using the
    difference in values given the distance from the transmitter.

[^219]: NAB reply comments at 8.

[^220]: *Id.* at 9.

[^221]: 47 U.S.C. § 339(a)(2)(D)(vii) specifies the dates on which the
    measurement of stations' signals may begin for the purpose of
    determining if a household is unserved. The earliest measurement
    date is April 30, 2006 for stations in top 100 markets that have
    chosen a tentative digital channel that is the same as its current
    digital channel or have lost interference protection and not been
    granted a testing waiver.

[^222]: Network Affiliates comments, exhibit 3 (rotors).

[^223]: *See* OET Bulletin 69, \"Longley-Rice Methodology for Evaluating
    TV Coverage and Interference\". A computer is needed to make these
    predictions because of the large number of reception points that
    must be individually examined. Computer code for the Longley-Rice
    point-to-point radio propagation model is published in an appendix
    of NTIA Report 82-100, A Guide to the Use of the ITS Irregular
    Terrain Model in the Area Prediction Mode, authors G.A. Hufford,
    A.G. Longley and W.A. Kissick, U.S. Department of Commerce, April
    1982. Some modifications to the code were described by G.A. Hufford
    in a memorandum to users of the model dated January 30, 1985. With
    these modifications, the code is referred to as Version 1.2.2 of the
    Longley-Rice model. This version is used by the FCC for its
    evaluations.

[^224]: *See* OET Bulletin 72, \"The ILLR Computer Program\". OET
    Bulletin 72 details the computer program that the Commission was
    instructed by Congress to established under SHVIA in Section
    339(c)(3) of the Communication Act. It provides that \"\[i\]n
    prescribing such model, the Commission shall rely on the Individual
    Location Longley-Rice (ILLR) model set forth by the Federal
    Communications Commission in Docket No. 98-201 and ensure that such
    model takes into account terrain, building structures, and other
    land cover variations.\" *See* also *See* *Satellite Delivery of
    Network Signals to Unserved Households for Purposes of the Satellite
    Home Viewer Act; Part 73 Definition and Measurement of Signals of
    Grade B Intensity*, Report and Order, CS Docket No., 98-201, 14 FCC
    Rcd 2654 (1999). A computer is needed to make these predictions
    because of the large number of reception points that must be
    individually examined. Computer code for the ILLR point-to-point
    radio propagation model is published in an appendix of NTIA Report
    82-100, *A Guide to the Use of the ITS Irregular Terrain Model in
    the Area Prediction Mode*, authors G.A. Hufford, A.G. Longley and
    W.A. Kissick, U.S. Department of Commerce, April 1982. Some
    modifications to the code were described by G.A. Hufford in a
    memorandum to users of the model dated January 30, 1985. With these
    modifications, the code is referred to as Version 1.2.2 of the
    Longley-Rice model.

[^225]: *Id*. The *Inquiry* indicated several features of the improved
    ILLR model that make it unique. These include: the time variability
    factor is 50% and the confidence variability factor is 50%; the
    model is run in individual mode; terrain elevation is considered
    every 1/10 of a kilometer; the receiving antenna height is assumed
    to be 20 feet above ground for one-story buildings and 30 feet above
    ground for buildings taller than one-story; land use and land cover
    (e.g., vegetation and buildings) is accounted for; where error codes
    appear, they shall be ignored and the predicted value accepted or
    the result shall be tested with an on-site measurement; and
    locations both within and beyond a station\'s Grade B contour shall
    be examined.

[^226]: See 47 U.S.C. § 339(c)(1)(B)(iv). 17 U.S.C. § 119(d)(10)
    provides the following definition of unserved household:

    > *(10) Unserved household.--- The term "unserved household", with
    > respect to a particular television network, means a household
    > that---*
    >
    > *(A) cannot receive, through the use of a conventional,
    > stationary, outdoor rooftop receiving antenna, an over-the-air
    > signal of a primary network station affiliated with that network
    > of Grade B intensity as defined by the Federal Communications
    > Commission under section 73.683(a) of title
    > [47](http://straylight.law.cornell.edu/uscode/html/uscode47/usc_sup_01_47.html)
    > of the Code of Federal Regulations, as in effect on January 1,
    > 1999;*
    >
    > *(B) is subject to a waiver granted under regulations established
    > under section 339(c)(2) of the Communications Act of 1934;*
    >
    > *(C) is a subscriber to whom subsection (e) applies;*
    >
    > *(D) is a subscriber to whom subsection (a)(11) applies; or*
    >
    > *(E) is a subscriber to whom the exemption under subsection
    > (a)(2)(B)(iii) applies.*

[^227]: *See* 47 U.S.C. § 339(c)(1)(B)(vi).

[^228]: DirecTv states that in last five years only 3,200 customers
    (0.3%) of those requesting distant network signals asked for an
    on-site test, and only about 1,400 of those actually received a
    test. DirecTv comments at 2.

[^229]: DirecTv comments at 2.

[^230]: *Id*. comments at 2-3.

[^231]: *Id*. comments at 3-4.

[^232]: *Id*. comments at 4-l

[^233]: CEA comments at 4.

[^234]: Network Affiliates comments at 44-45.

[^235]: *Id*. comments at 43-44.

[^236]: NAB comments at vi-vii and 31-33.

[^237]: *Id*. comments at 31. The testing referred to here is the
    measurement at an individual subscriber's location of a digital
    television signal level for the purpose of determining if the
    subscriber at that location is considered unserved and therefore
    eligible to receive a distant network signal.

[^238]: *Id*. comments at 34-35. 47 U.S.C. § 339(a)(2)(D)(vii) provides
    trigger dates for testing. NAB characterizes the schedule set up by
    Congress as testing to begin on April 30, 2006, for stations in top
    100 markets that have chosen a tentative digital channel that is the
    same as its current digital channel and have not been granted a
    testing waiver and for stations in top 100 markets that have been
    found to have lost interference protection. Testing begins on July
    15, 2007 for stations in top 100 markets that have chosen a
    tentative digital channel different from its current digital channel
    and have not been granted a testing waiver and for stations below
    the top 100 markets that have not been granted a testing waiver.
    Finally, there are unknown future dates for translator stations --
    one year after the date on which commission completes all actions
    necessary for allocation and assignment of digital television
    licenses to translator stations; and for full power stations with
    testing waivers -- continue to be exempt from testing as long as
    extensions of waivers are approved.

[^239]: *Id*. at 36.

[^240]: Network Affiliates comments at 43-44.

[^241]: NAB comments at 37.

[^242]: *Id*. NAB comments at vi.

[^243]: NAB comments at MSW engineering study at 28.

[^244]: EchoStar comments at 9.

[^245]: As discussed below (and above in the section on signal
    strength), the signal strength standards in the rules are in fact
    based on an F(50,90) level of signal availability, which implies
    that a signal would be available at least 90% of the time, not 50%
    as EchoStar incorrectly states.

[^246]: *Id*.

[^247]: EchoStar comments at H&E engineering study at 7.

[^248]: NAB reply comments at 8; Network Affiliates reply comments at 8.

[^249]: MSW reply comments at 10; Network Affiliates reply comments at
    7.

[^250]: Impedance is the total passive opposition offered to the flow of
    electric current, *see* Federal Standard 1037C, "Telecommunications:
    Glossary of Telecommunications Terms, 1996."

[^251]: EchoStar comments at 10.

[^252]: Voltage standing wave ratio is the ratio of the maximum to the
    minimum voltage in a standing wave pattern in a transmission line.
    VSWR is a measure of impedance mismatch between a transmission line
    and its load; the higher the VSWR, the greater the mismatch, where a
    VSWR of 1 corresponds to a perfect impedance match. *See* Federal
    Standard 1037C, "Telecommunications: Glossary of Telecommunications
    Terms, 1996."

[^253]: EchoStar comments at H&E engineering statement at 11-12.

[^254]: MSW reply comments at 14.

[^255]: EchoStar comments at 10.

[^256]: MSW reply comments at 14.

[^257]: EchoStar comments at 10-11.

[^258]: Network Affiliates comments at 44-47.

[^259]: NAB comments at MSW engineering study at 28.

[^260]: \[add a cite to the NAB and Network Affiliates Comments\]

[^261]: *See, e.g.,* 47 U.S.C. § 339(a)(2)(D)(viii). These provisions
    further recognize that household digital signal testing with respect
    to translators is on a different schedule from full power stations.
    47 U.S.C. § 339(a)(2)(D)(vii)(II).

[^262]: 47 U.S.C. § 339(a)(2)(D)(vii)(I).

[^263]: 47 U.S.C. § 339(a)(2)(D)(viii). *See also* 47 U.S.C. §
    339(a)(2)(D)(ix) (providing special waiver provision for translator
    stations).

[^264]: 47 U.S.C. § 339(a)(2)(D)(viii), (ix).

[^265]: *See* 47 C.F.R. § 73.622(e).

[^266]: NAB reply comments at 11.

[^267]: *See* *ILLR First Report and Order* at ¶¶ 14-15.

[^268]: *Id.*

[^269]: 8-level Vestigial Side Band (8-VSB) is the over-the-air digital
    television (DTV) transmission format recommended by the Advanced
    Television Systems Committee (ATSC) and adopted by the FCC as the
    U.S. standard for terrestrial DTV transmission.

[^270]: 8-level Vestigial Side Band (8-VSB) is the over-the-air digital
    television (DTV) transmission method recommended by the Advanced
    Television Systems Committee (ATSC) and adopted by the FCC as the
    U.S. standard for terrestrial DTV transmission.

[^271]: Citta, Richard, and Sgrignoli, Gary, "ATSC Transmission System:
    VSB Tutorial", Montreuz Symposium, June 12, 1997, p.8.

[^272]: Sgrignoli, Gary, "Interference Analysis of Co-Sited DTV and NTSC
    Translators", IEEE Transactions on Broadcasting, Vol. 51, No. 1,
    March 2005, p.3.

[^273]: Eilers, Carl, and Sgrignoli, Gary, "Digital Television
    Transmission Parameters\-- ATSC Compliance Factors", IEEE
    Transactions on Broadcasting, Vol. 45, No. 4, December 1999, p.12.

[^274]: Laud, Tim, Aitken, Mark; Bretl, Wayne; and Kwak, K. Y.,
    "Performance of 5th Generation 8-VSB Receivers", IEEE Transactions
    on Consumer Electronics, Vol. 50, No. 4, November 2004.

[^275]: "ATSC Recommended Practice: Receiver Performance Guidelines",
    ATSC Doc. A/74, Advanced Television Systems Committee, 17 June 2004,
    p.24.

[^276]: Final Technical Report, FCC Advisory Committee on Advanced
    Television Service's (ACATS), October 31, 1995, p.15 (Table 5.1).

[^277]: "ATSC Recommended Practice: Receiver Performance Guidelines",
    ATSC Doc. A/74, Advanced Television Systems Committee, 17 June 2004.

[^278]: The vector signal analyzer specification sheet states that
    relative accuracy in RF vector mode on a single range is the sum of
    frequency response and amplitude linearity. If we ignore the
    frequency response term because the measurements are made over the
    same frequency range, we are left with the amplitude linearity term,
    which is specified as "\<0.1 dB" for signal levels between 0 dB and
    -30 dB with respect to full scale---a condition that was met by both
    the signal and injected noise measurements. To this we add errors
    caused by the 0.1‑dB attenuator step size.

[^279]: Span does not match difference between worst and best due to
    rounding of all numbers to nearest 0.1 dB.

[^280]: As an additional check on equipment performance, measurements of
    injected broadband signal level and of injected broadband noise
    level---at levels typical of those used for white-noise threshold
    testing (-70 dBm for noise and -55 dBm for signal---both measured
    across the 6-MHz bandwidth of TV channel 30)---were performed using
    two instruments, the vector signal analyzer and a spectrum analyzer
    (Agilent E7405A). The spectrum analyzer measurements were made with
    the internal preamp on and the internal attenuation set to 0 dB. The
    spectrum analyzer overall amplitude accuracy is specified as "±(0.54
    dB + absolute frequency response)" with the absolute frequency
    response being specified as ±0.5 dB over the frequency range of
    interest. For both signal and noise, the spectrum analyzer
    measurements were 0.1 dB higher than the vector signal analyzer
    measurements---suggesting that both instruments (which were
    calibrated no more than two months before the measurements reported
    in this chapter) were likely performing well within the specified
    tolerances. (Note that self calibrations were also performed on both
    instruments before each set of measurements.)

[^281]: "*ATSC Recommended Practice: Receiver Performance Guidelines*",
    ATSC Doc. A/74, Advanced Television Systems Committee, 17 June 2004,
    p.11.

[^282]: See note for Table 1-1.

[^283]: Absolute measurement accuracy of the vector signal analyzer on
    the amplitude range that was used for the measurements was as ±1.5
    dB maximum and ±0.5 dB typical.

[^284]: As is explained in Chapter 3, the statistical assessment
    performed above is dependent upon a number of assumptions that are
    not strictly true for the case at hand. Arguably, the most
    questionable of these is the assumption that the performance of the
    each receiver sample is independent of the others. It is quite
    likely that some of the receiver samples share critical subsystems,
    which would violate the independence assumption. For example a given
    tuner or demodulator design may be used in more than one of the
    receivers. The effect of such a commonality between samples would be
    to decrease the effective number of degrees of freedom in the
    computed Pearson's correlation coefficient. Such a decrease would
    increase the magnitude of correlation that would have to be observed
    to have a given confidence level in the result. Taking this effect
    into account would further diminish any statistical significance of
    the results.

[^285]: Various receiver design anomalies could result in reception
    sensitivity being limited by factors other than receiver noise
    (noise figure). For example, if the AGC (automatic gain control)
    does not allow sufficient RF and IF gain to amplify a weak signal to
    the level necessary for demodulation, reception performance will be
    limited by gain rather than by amplifier noise. Similarly, receiver
    performance could also be limited by local oscillator phase noise or
    by leakage into the tuner of internally-generated interference
    sources such as impulse noise from digital circuits or narrowband
    (tonal) interference.

[^286]: The reference temperature is generally taken as the antenna
    temperature. 290°K = 17°C = 62°F results in a thermal noise level
    matching the -106.2 dB value used in OET‑69.

[^287]: Absolute measurement accuracy of the vector signal analyzer on
    the amplitude range that was used for the measurements was as ±1.5
    dB maximum and ±0.5 dB typical.

[^288]: *"ATSC Recommended Practice: Receiver Performance Guidelines"*,
    ATSC Doc. A/74, Advanced Television Systems Committee, 17 June 2004.

[^289]: Ibid., p. 15.

[^290]: See Table B-1 of this report or the "Quality of Capture" column
    of the continuation of Figure A-1 on p.28 of *"ATSC Recommended
    Practice: Receiver Performance Guidelines"*, ATSC Doc. A/74,
    Advanced Television Systems Committee, 17 June 2004.

[^291]: The Program and System Information Protocol (PSIP) includes a
    field for establishing this association. Further information is
    available in Advanced Television Systems Committee documents A/65B
    "*ATSC Standard: Program and System Information Protocol for
    Terrestrial Broadcast and Cable (Revision B)*" and A/69 "*ATSC
    Recommended Practice: Program and System Information Protocol
    Implementation Guidelines for Broadcasters" for more information*."

[^292]: Receiver D1 belongs in the "lower tier+" category because it
    performed above the range of performance for the lower tier both in
    terms of number of captures played with no errors and number of
    captures played with two or fewer errors. The case for placing
    receiver L2 in the "lower tier+" category rather than in the lower
    tier is weaker, since only one of its performance numbers (number of
    captures played with two or fewer errors) was above the lower tier
    range.

[^293]: With 8-VSB, each transmission segment consists of one MPEG
    packet. Thus, a segment error is equivalent to an MPEG packet error.

[^294]: In general, visual errors are expected to occur only when
    segment errors occur, but the reverse is not always true, depending
    on effectiveness of MPEG error concealment algorithms for the video
    content at the time of the errors.

[^295]: One of the tested set-top-box models was released to the market
    in August 2003. The other four were released between July and
    November 2004.

[^296]: 15.3 dB is the median value for those receivers identified as
    lower tier---not including those identified as "lower tier+". If the
    lower tier+ receivers are included, the median is 15.4 dB.

[^297]: "Final Technical Report", Federal Communications Commission
    Advisory Committee on Advanced Television Service (ACATS), October
    31, 1995, p.19.

[^298]: Inglis, William H. and Means, David L., *"A Study Of ATSC
    (8-VSB) DTV Coverage In Washington, DC,*

    *And Generational Changes In DTV Receiver Performance"*, Interim OET
    Report FCC/OET TRB-00-2, Technical Research Branch, Laboratory
    Division, Office of Engineering and Technology, Federal
    Communications Commission, April 9, 2001.

[^299]: More specifically, 200 sites were randomly selected within the
    17.5-mile box. The tested sites were selected from among
    these---focusing on sites located in Washington, DC and sites near
    the FCC Laboratory, in Columbia, MD.

[^300]: With the mast-mounted antenna, 51 sites were tested. With the
    tripod-mounted antennas, 50 sites were tested. In both cases, all
    but one site had sufficient field strength for theoretical DTV
    reception.

[^301]: Out of the 50 sites that had sufficient field strength for
    theoretical DTV reception.

[^302]: The indoor antenna was mounted at a 7-foot height, consistent
    with indoor antenna, but tests were performed outdoors.

[^303]: "ATSC Recommended Practice: Receiver Performance Guidelines",
    ATSC Doc. A/74, Advanced Television Systems Committee, 17 June 2004,
    p.11.

[^304]: See note for Table 1-1.

[^305]: The intent was both to minimize standing waves on the 25-foot,
    low-loss cables and to reduce the impact of RF energy reflected back
    from a poorly matched TV on signals delivered to other TVs through
    the splitter.

[^306]: \"Control Software for the HP89400 Vector Signal Analyzer for
    Measuring DTV and NTSC Signals\", VSA5.BAS, Version 5.02, Gary
    Sgrignoli

[^307]: \"Control Software for the HP89400 Vector Signal Analyzer for
    Measuring DTV and NTSC Signals\", VSA5.BAS, Version 5.02, Gary
    Sgrignoli

[^308]: \"Control Software for the HP89400 Vector Signal Analyzer for
    Measuring DTV and NTSC Signals\", VSA5.BAS, Version 5.02, Gary
    Sgrignoli

[^309]: See Table B-1 in Appendix B of this report, or the "Quality of
    Capture" column of the continuation of Figure A-1 on p.28 of *"ATSC
    Recommended Practice: Receiver Performance Guidelines"*, ATSC Doc.
    A/74, Advanced Television Systems Committee, 17 June 2004.

[^310]: The Satellite Home Viewer Extension and Reauthorization Act of
    2004, Pub. L. No. 108-447, § 207, 118 Stat 2809, 3393 (2004) (to be
    codified at 47 U.S.C. § 325), § 204(b). The SHVERA was enacted as
    title IX of the "Consolidated Appropriations Act, 2005."

[^311]: 17 U.S.C. § 119. The Satellite Home Viewer Act is part of this
    copyright statute.

[^312]: *Satellite Delivery of Network Signals to Unserved Households
    for Purposes of the Satellite Home Viewer Act*, CS Docket No.
    98-201, *Report and Order*, 14 FCC Rcd 2654 at ¶ 2 (1999) (*SHVA
    Report and Order*).

[^313]: 17 U.S.C. §§ 119, 122 (Copyright Act provisions); 47 U.S.C. §§
    325, 338, 339 (Communications Act provisions).

[^314]: *See* 17 U.S.C. § 119(d)(10)(A); *see* also 47 CFR § 73.683(a).
    Section 119(d)(10) (A) of the Copyright Act defines an unserved
    household as a "household that cannot receive, through use of a
    conventional stationary, outdoor rooftop receiving antenna, an
    over-the-air signal of a primary network television station
    affiliated with that network of Grade B intensity as defined by the
    Federal Communications Commission under section 73.683(a) of title
    47 of the Code of Federal Regulations, as in effect on January 1,
    1999." Section 73.683(a) sets forth field strength levels for the
    Grade B coverage contours of analog TV stations as follows, units
    are one micro-volt per meter (dBµ): channels 2-6 47 dBµ, channels
    7-13 56 dBµ, channels 14-69 64 dBµ.

[^315]: *SHVA Report and Order,* 14 FCC Rcd 2654 at ¶ 4.

[^316]: *Id.* at ¶ 71. The Individual Location Longley-Rice (ILLR)
    predictive model is used to predict the Grade B signal intensity at
    a location. 47 CFR Section 73.686(d) specifies the measurement
    procedure used to obtain the signal intensity at an individual
    location.

[^317]: 47 CFR § 73.622(e). *See also* 47 CFR § 73.625(b) (determining
    coverage).

[^318]: The Satellite Home Viewer Improvement Act of 1999, Pub.L. No
    106-113, 113 Stat. 1501 (1999) (codified in scattered sections of 17
    and 47 U.S.C.). The SHVIA was enacted on November 29, 1999, as Title
    I of the Intellectual Property and Communications Omnibus Reform Act
    of 1999 (IPACORA) (relating to copyright licensing and carriage of
    broadcast signals by satellite carriers).

[^319]: *See* SHVIA, section 1008.

[^320]: *See* *Satellite Delivery of Network Signals to Unserved
    Households for Purposes of the Satellite Home Viewer Act; Part 73
    Definition and Measurement of Signals of Grade B Intensity*, Report
    and Order, CS Docket No., 98-201, 14 FCC Rcd 2654 (1999). A computer
    is needed to make these predictions because of the large number of
    reception points that must be individually examined. Computer code
    for the ILLR point-to-point radio propagation model is published in
    an appendix of NTIA Report 82-100, *A Guide to the Use of the ITS
    Irregular Terrain Model in the Area Prediction Mode*, authors G.A.
    Hufford, A.G. Longley and W.A. Kissick, U.S. Department of Commerce,
    April 1982. Some modifications to the code were described by G.A.
    Hufford in a memorandum to users of the model dated January 30,
    1985. With these modifications, the code is referred to as Version
    1.2.2 of the Longley-Rice model.

[^321]: *Id*. at ¶69.

[^322]: *See* 47 C.F.R. 73.683 (a), and 47 C.F.R. 73.684 (c).

[^323]: The Grade B signal contour describes a boundary around a
    television station's transmitter. As set forth in Section 73.683(a),
    a signal of Grade B intensity is defined as a discrete value
    measured in units of dBµv/m (dB over a microvolt per meter).
    However, the absolute intensity of broadcast signals at particular
    locations and at particular times cannot be precisely determined
    through predictive means, regardless of the predictive method used.
    Signal strength varies randomly over location and time, so signal
    propagation must be considered on a statistical basis. This is true
    regardless of whether the signal intensity is predicted at a fixed
    location (such as an individual household) or over an area. Some
    prediction methods, including the Commission's field strength charts
    (propagation curves), predict the occurrence of median signal
    strengths (i.e., signal strengths predicted to be exceeded at 50% of
    the locations in a particular area at least 50 percent of the time).
    Using these methods, "location" and "time" variability factors are
    added to the signal level for an acceptable picture so that the
    desired statistical reliability, *i.e.*, 50 percent of locations 90
    percent of the time, is achieved. The values chosen for the Grade B
    signal intensity standards account for this variability and,
    therefore, as indicated above, predict that at least 50 percent of
    the locations along the Grade B contour will receive an acceptable
    picture 90 percent of the time. For additional information on Grade
    B contours, see "Understanding Television's Grade A and Grade B
    Service Contours."

[^324]: *See* section 339(c)(1) of the Communications Act of 1934, as
    amended by the SHVIA, section 1008.

[^325]: *See* *Technical Standards for Determining Eligibility for
    Satellite-Delivered Network Signals Pursuant to the Satellite Home
    Viewer Improvement Act*, *Report*, ET Docket No. 00-90, FCC 00-416
    (2000); *see also id., Notice of Inquiry*, FCC 00-184, released May
    26, 2000.

[^326]: The eight planning factors that the Commission recommended
    should be unchanged were the: Thermal Noise Factor; Receiver Noise
    Figure; Signal-to-Noise Ratio and Service Quality; Transmission Line
    Loss; Receiving Antenna Gain; Dipole Factor; Terrain Variability;
    and Environmental Noise.

[^327]: The DTV Table of Allotments is set forth in Section 73.622(b) of
    the rules, 47 C.F.R. § 73.622(b).

[^328]: "Noise-limited" service means that reception of service at the
    described signal level is only limited by the presence of
    radiofrequency noise that is expected to be present at the same
    level as the desired signal.

[^329]: *See* 47 C.F.R. § 73.622 (e)(1) and (2). The F(50,90) level of
    service was established for DTV service areas to account for the
    fact that DTV service is subject to a "cliff effect" by which full
    quality service becomes totally unavailable within a very small
    decrease in signal strength whereas analog TV service quality
    degrades gradually with declining signal strength. The distance to
    field strength contours with service at the F(50, 90) levels of
    service is determined using the charts in Section 73.699 of the
    rules, 47 C.F.R. § 73.699.

[^330]: *See SHVERA, supra* note 1.

[^331]: Section 102 of the SHVERA creates a new 17 U.S.C. § 119(a)(3) to
    provide satellite carriers with a statutory copyright license to
    offer "significantly viewed" signals as part of their local service
    to subscribers. 17 U.S.C. § 119(a)(3).

[^332]: *See* 47 U.S.C. §§ 325, 338, 339 and 340.

[^333]: *See* 17 U.S.C. § 119(d)(10); 47 C.F.R. § 73.622(e)(1); 47
    C.F.R. § 73.686(d).

[^334]: *See* SHVERA, *supra* note 1, at § 204(b)(1)(B).

[^335]: *See* 47 C.F.R. § 73.622(e).

[^336]: *See* OET Bulletin 69, "Longley-Rice Methodology for Evaluating
    TV Coverage and Interference".

[^337]: *Id.*

[^338]: *See* 47 CFR 73.686(d).

[^339]: *See* 47 C.F.R. §§ 73.686(d)(1)(i) and 73.686(d)(2)(i).

[^340]: The pilot signal is located 0.31 MHz inside the lower band edge
    of the spectrum and is 3 dB lower than the average power of the
    signal.

[^341]: 17 U.S.C. § 119(d)(10) provides the following definition of
    unserved household:

    > *(10) Unserved household.--- The term "unserved household", with
    > respect to a particular television network, means a household
    > that---*
    >
    > *(A) cannot receive, through the use of a conventional,
    > stationary, outdoor rooftop receiving antenna, an over-the-air
    > signal of a primary network station affiliated with that network
    > of Grade B intensity as defined by the Federal Communications
    > Commission under section 73.683(a) of title
    > [47](http://straylight.law.cornell.edu/uscode/html/uscode47/usc_sup_01_47.html)
    > of the Code of Federal Regulations, as in effect on January 1,
    > 1999;*
    >
    > *(B) is subject to a waiver granted under regulations established
    > under section 339(c)(2) of the Communications Act of 1934;*
    >
    > *(C) is a subscriber to whom subsection (e) applies;*
    >
    > *(D) is a subscriber to whom subsection (a)(11) applies; or*
    >
    > *(E) is a subscriber to whom the exemption under subsection
    > (a)(2)(B)(iii) applies.*

[^342]: *See* OET Bulletin 69, \"Longley-Rice Methodology for Evaluating
    TV Coverage and Interference\". A computer is needed to make these
    predictions because of the large number of reception points that
    must be individually examined. Computer code for the Longley-Rice
    point-to-point radio propagation model is published in an appendix
    of NTIA Report 82-100, A Guide to the Use of the ITS Irregular
    Terrain Model in the Area Prediction Mode, authors G.A. Hufford,
    A.G. Longley and W.A. Kissick, U.S. Department of Commerce, April
    1982. Some modifications to the code were described by G.A. Hufford
    in a memorandum to users of the model dated January 30, 1985. With
    these modifications, the code is referred to as Version 1.2.2 of the
    Longley-Rice model. This version is used by the FCC for its
    evaluations.

[^343]: *See* OET Bulletin 72, \"The ILLR Computer Program\". OET
    Bulletin 72 details the computer program that the Commission was
    instructed by Congress to established under SHVIA in Section
    339(c)(3) of the Communication Act. It provides that \"\[i\]n
    prescribing such model, the Commission shall rely on the Individual
    Location Longley-Rice \[ILLR\] model set forth by the Federal
    Communications Commission in Docket No. 98-201 and ensure that such
    model takes into account terrain, building structures, and other
    land cover variations.\" *See* also *Report and Order* CS Docket No.
    98-201 *supra* note Error: Reference source not found, and
    *Satellite Delivery of Network Signals to Unserved Households for
    Purposes of the Satellite Home Viewer Act,* CS Docket No.98-201,
    *Memorandum Opinion and Order*, 14 FCC Rcd 31 17373. (1999).

[^344]: *Id.*

[^345]: *See* *Report and Order* in CS Docket No. 98-201 ¶71 *supra*
    note Error: Reference source not found.

[^346]: *See* In The Matter of Advanced Television Systems And Their
    Impact Upon the Existing Television Broadcast Service, *Memorandum
    Opinion and Order on Reconsideration of the Sixth Report and Order*,
    MM Docket No. 87-268, 13 FCC Rcd. 7418, 7551 (1998) ¶ 171.

[^347]: *See Report and Order and Further Notice of Proposed
    Rulemaking*, in MM Docket No.00-39 (first DTV periodic review
    proceeding), 16 FCC Rcd 5946 at ¶ 96.

[^348]: Greater sensitivity can also result in reception of unwanted
    signals at low levels that then must be eliminated or attenuated by
    the selectivity characteristics of the receiver.

[^349]: There are several ways to describe the selectivity of a radio
    receiver. One way is to simply give the bandwidth of the receiver
    over which its response level is within 3 dB of its response level
    at the center frequency of the desired signal. This measure is often
    termed the "bandwidth over the -3db points." This bandwidth,
    however, is not necessarily a good means of determining how well the
    receiver will reject unwanted frequencies. Consequently, it is
    common to give the receiver bandwidth at two levels of attenuation;
    for example, -3dB and -60 dB. The ratio of these two bandwidths is
    called the shape factor. Ideally, the two bandwidths would be equal
    and the shape factor would be one. However, this value is very
    difficult to achieve in a practical circuit.