**NTIA Report 05-432**![](media/image1.wmf){width="6.502777777777778in"
height="3.251388888888889in"}

Interference Protection Criteria

**Phase 1 - Compilation from Existing Sources**

*technical report*

**U.S. DEPARTMENT OF COMMERCE National Telecommunications and
Information Administration**

**NTIA Report 05-432**

Interference Protection Criteria

**Phase 1 - Compilation from Existing Sources**

**Alakananda Paul**

**Gerald Hurt**

**Thomas Sullivan**

**Gary Patrick**

**Robert Sole**

**Larry Brunson**

**Cou-Way Wang**

**Bernard Joiner**

**Edward Drocella**

***Contributors***

**Suzette Williams**

**Gentiana Saam**

![](media/image2.jpeg){width="1.7583333333333333in"
height="1.7472222222222222in"}

**U.S. Department of Commerce**

**Carlos M. Guiterrez, Secretary**

Michael D. Gallagher, Assistant Secretary

for Communications and Information

**October 2005**

[]{#__RefHeading___Toc118091098 .anchor}EXECUTIVE SUMMARY

The National Telecommunications and Information Administration (NTIA)
launched this two-phase study of interference protection criteria (IPC)
in order to compile, explain and validate, modify or supplement the
levels of protection from interference that are generally expected and
provided for various radiocommunication systems. The study is an
integral part of President Bush's Spectrum Policy Initiative that was
established in May 2003 to promote the development and implementation of
a United States spectrum policy for the 21st century. The Secretary of
Commerce then established a Federal Government Spectrum Task Force and
initiated a series of public meetings to address improvements in
policies affecting spectrum use by the Federal Government, State, and
local governments, and the private sector. The recommendations resulting
from these activities were included in a two-part series of reports
released by the Secretary of Commerce in June 2004, under the title
*Spectrum Policy for the 21st Century - The Presidents Spectrum Policy
Initiative*. Based on the recommendations contained in these Reports,
the President directed the federal agencies on November 30, 2004, to
plan the implementation of the 24 recommendations contained in the
Reports. There were several recommendations that will consider the
interference protection criteria contained in this study including:

-   assessment of new technologies and their impact on incumbent
    radiocommunications;

-   managing interference;

-   development of a "Best Practices Handbook" for spectrum engineering;

-   establishment a pilot program and long-range plan for improved
    sharing of spectrum between federal and non-federal entities; and

-   creation of new analytical computer models that will facilitate
    spectrum engineering.

The U.S. spectrum management process has evolved to meet the rapidly
changing spectrum requirements of both the private sector and the
federal government. Within this spectrum management process, the Federal
Communications Commission (FCC), acting on behalf of the private sector,
and the NTIA, acting on behalf of the federal agencies, provide spectrum
planning, allocation and assignment in a manner that prevents
interference. In the last five to ten years, spectrum usage and demand
have increased significantly. Associated with the increased spectrum
usage demand, came the increased geographic densities of transmitters
and receivers, that means increased interference risks. One of the key
elements in preventing interference is identification of the appropriate
IPC. Implementation of a new technology often requires a significant
amount of time to define and obtain agreement on an appropriate IPC. For
example, it took several years to obtain sufficient measurement and
analytical information on potential interference from ultrawideband
(UWB) devices in order to define and apply the necessary IPC. To speed
up the introduction of a new technology associated with the addition of
licensed or unlicensed operations, means that advocates, incumbents and
regulators will have to find more effective ways for analyzing the
potential interference in a more timely manner. To this end, it is
appropriate to predict and define the interfering signal levels at which
radio systems may experience unacceptable degradation in performance,
and to establish methods for protection of radio communications from
interference.

One of the key steps in any interference, electromagnetic compatibility,
or spectrum sharing study is identifying IPC, to determine the necessary
distance or frequency separations, or other frequency sharing
constraints. The identification of IPC is often a confusing,
time-consuming step with no single reference source from which to draw.
The complexity of this process is exacerbated by the numerous terms used
to define interference. For example, the NTIA, FCC, and International
Telecommunication Union, Radiocommunication Sector or (ITU-R), define
various terms relative to interference, including: *Interference,
Permissible Interference, Accepted Interference,* and *Harmful
Interference.* The diverse concepts behind these terms can lead to
confusion when addressing potential interference between systems.
Furthermore, since IPC normally depend upon details of the interfering
and interfered-with systems as well as their operating environments, a
very large number of combinations of frequency sharing situations must
be considered with regard to a proposed new service or technology.

NTIA reviewed publications of national, international, public and
private organizations to compile established IPC for various radio
services operating between 30 MHz and 30 GHz. The results are presented
in this Phase 1 report. One common feature was that for continuous,
long-term interfering signal levels, nearly all established IPC were
based on an interference-to-noise power ratio of --6 to --10 dB.
Short-term IPC that accommodate relatively high interfering signal
levels for small percentages of time or locations were not found for
many services. For pulsed or intermittent interfering signals, the IPC
for many of the radio services were not specified or the available IPC
varied due to the specific types of desired and interfering signals
being received.

In the second phase of this study, NTIA will review the relevant federal
government policies and practices regarding IPC and recommend regulatory
and technical refinements that may improve IPC application's scope,
utility, clarity, or effectiveness.

[]{#__RefHeading___Toc118091099 .anchor}ACRONYMS AND ABBREVIATIONS

  ------------------ ----------------------------------------------------
                     

  AFTRCC             Aerospace and Flight Test Radio Coordinating Council

  AI                 Articulation Index

  AMSS               Aeronautical Mobile-Satellite Service

  AMS(OR)S           Aeronautical Mobile-Satellite Service (Off-route)

  AMS(R)S            Aeronautical Mobile-Satellite Service (Route)

  ANSI               American National Standards Institute

  AP30               Appendix 30 of the ITU Radio Regulations

  APCO               Association of Public-Safety Communications
                     Officials

  APT                Automatic Picture Transmission

  ARINC              Aeronautical Radio Incorporated

  ATCRBS             Air Traffic Control Radar Beacon System

  ATM                Air Traffic Management

  ATPC               Automatic Transmitter Power Control

  ATSC               Advanced Television Systems Committee

  BBER               Background Block Error Ratio

  BEP                Bit Error Probability

  BER                Bit Error Ratio

  BS                 Broadcasting Service

  BSS                Broadcasting-Satellite Service

  BW                 Bandwidth

  C/A                Coarse Acquisition

  CATV               Community Antenna Television

  CCIR               International Radio Consultative Committee (now
                     called "ITU-R")

  CDA                Command and Data Acquisition System

  CD                 Color Decoding

  CDMA               Code Division Multiple Access

  CEPT               European Conference of Postal and Telecommunications
                     Administrations

  CFR                Code of Federal Regulations

  C/I                Carrier-to-Interfering Signal Power Ratio

  C/(I+N)            Carrier-to-Interference-plus-Noise Power Ratio

  C/N                Carrier-to-Noise Power Ratio

  CW                 Continuous Wave

  DAQ                Delivered Audio Quality

  dB                 Decibel

  dBi                Antenna gain in dB over isotropic

  dBic               Antenna gain in dB over isotropic (circular
                     polarized)

  dBm                Power in dB referred to 1 milliwatt

  dBμ                Field strengths in dB above one microvolt per meter

  DBS                Direct Broadcast Satellite

  dBW                Power in dB referred to 1 watt

  dBZ                Radar reflectivity factor in dB

  DME                Distance Measuring Equipment

  DMS                Digital Microwave System

  DNR                Draft New Recommendation

  DOD                Department of Defense

  DRS                Data Relay Satellite

  DTV                Digital Television

  D/U                Desired-To-Undesired Signal Power Ratio

  DVB-T              Digital Video Broadcasting-Terrestrial

  ECC                Electronic Communications Committee

  EES                Earth Exploration-Satellite

  EIA                Electronics Industry Alliance

  EMC                Electromagnetic Compatibility

  ERO                European Radiocommunications Organization

  ESR                Errored Second Ratio

  ETSI               European Telecommunications Standards Institute

  EVA                Extra-Vehicular Activity

  FAA                Federal Aviation Administration

  FCC                Federal Communications Commission

  FDMA               Frequency Division Multiple Access

  FDP                Fractional Degradation of Performance

  FEC                Forward Error Correction

  FH                 Frequency Hopping

  FM                 Frequency Modulation

  FS                 Fixed Service

  FSS                Fixed-Satellite Service

  GHz                Gigahertz (10^9^ Hertz)

  GLONASS            Global Navigation Satellite System (Russian)

  GNSS               Global Navigation Satellite System

  GPS                Global Positioning System

  GRD                Global Recorded Data

  GSO                Geostationary Satellite Orbit

  HDTV               High Definition Television

  HRDP               Hypothetical Reference Digital Path

  HRPT               High Resolution Picture Transmission

  Hz                 Hertz

  IBOC               In-band on-channel

  ICAO               International Civil Aviation Organization

  IEC                International Electrotechnical Commission

  IEEE               Institute of Electrical and Electronics Engineers

  ILS                Instrument Landing System

  IMO                International Maritime Organization

  IMT-2000           International Mobile Telecommunications-2000

  I/N                Interfering-to-Noise Power Ratio

  IP                 Internet Protocol

  IPC                Interference Protection Criteria

  ISDB-T             Integrated Service Digital Broadcasting-Terrestrial

  ISDN               Integrated Services Digital Network

  ISM                Industrial, Scientific, and Medical

  ITU                International Telecommunication Union

  ITU-R              ITU Radiocommunication Sector

  ITU-T              ITU Telecommunications Standardization Sector

  JSC                Joint Spectrum Center

  JTF                Joint Task Force

  K                  Kelvin

  Kbps               Kilobits per second

  kHz                Kilohertz (10^3^ Hertz)

  LMSS               Land Mobile-Satellite Service

  LEO                Low Earth Orbit

  LRPT               Low Resolution Picture Transmission

  m                  Meter

  Mb/s               Megabits per second

  MEA                Multiple Exposure Allowance

  METSAT             Meteorological-Satellite

  MHz                Megahertz (10^6^ Hertz)

  MIL-STD            Military Standard

  MLS                Microwave Landing System

  MMSS               Maritime Mobile-Satellite Service

  MS                 Mobile Service

  MSS                Mobile-Satellite Service

  MVDDS              Multi-Channel Video Distribution and Data Service

  N/C                Noise-to-Carrier Ratio

  NGSO               Non-Geostationary Satellite Orbit

  NIB                Non-Interference-Basis

  NPRM               Notice of Proposed Rulemaking

  N/S                Not Specified

  NTIA               National Telecommunications and Information
                     Administration

  NTSC               National Television Standards Committee

  NWS                National Weather Service

  NWP                Numerical Weather Prediction

  OSM                Office of Spectrum Management

  OSS                One-Stop-Shopping Procedure

  PCM                Pulse Code Modulation

  pfd                Power Flux Density

  PLMR               Private Land Mobile Radio

  QPSK               Quadrature Phase Shift Keying

  RA                 United Kingdom Radiocommunications Agency

  RAS                Radio Astronomy Service

  Rec                Recommendation

  RF                 Radio Frequency

  RMS                Root Mean Square

  RNSS               Radionavigation-Satellite Service

  RR                 Radio Regulations

  RTCA               Radio Technical Commission on Aeronautics

  RTCM               Radio Technical Commission on Maritime

  SAR                Synthetic Aperture Radars

  SCPC               Single Channel Per Carrier

  SESR               Severely Errored Second Ratio

  SG                 Study Group

  S/I                Signal-to-Interference Power Ratio

  SINAD              Signal to Interference, Noise, and Distortion Power
                     Ratio

  SPTF               Spectrum Policy Task Force

  TACAN              Tactical Air Navigation

  TBD                To Be Determined

  TDMA               Time Division Multiple Access

  TIA                Telecommunications Industry Association

  TSB                Telecommunications Systems Bulletin

  UHF                Ultra High Frequency -- 300 to 3000 MHz

  USCG               United States Coast Guard

  UWB                Ultrawideband

  VHF                Very High Frequency -- 30 to 300 MHz

  VLBI               Very Long Baseline Interferometry

  VOR                Very-High-Frequency Omnidirectional Range

  VSAT               Very Small Aperture Terminal

  WAAS               Wide Area Augmentation System

  WEFAX              Weather Facsimile

  WMO                World Meteorological Organization

  WP8B               ITU-R Working Party 8B

  WRC                World Radiocommunication Conference
  ------------------ ----------------------------------------------------

[]{#__RefHeading___Toc118091100 .anchor}TABLE OF CONTENTS

EXECUTIVE SUMMARY [i](#__RefHeading___Toc118091098)

ACRONYMS AND ABBREVIATIONS [iii](#__RefHeading___Toc118091099)

TABLE OF CONTENTS [vii](#__RefHeading___Toc118091100)

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

1.1 BACKGROUND [1-1](#background)

1.2 OBJECTIVE [1-4](#objective)

1.3 PHASE 1 APPROACH [1-5](#phase-1-approach)

1.4 SCOPE [1-5](#scope)

Section 2 TECHNICAL perspectives [2-1](#technical-perspectives)

2.1 INTRODUCTION [2-1](#introduction-1)

2.2 Relevant Definitions [2-1](#relevant-definitions)

2.3 Elements of Interference Protection Criteria
[2-2](#elements-of-interference-protection-criteria)

Section 3 OVERVIEW [3-1](#overview)

3.1 INTRODUCTION [3-1](#introduction-2)

3.2 Fixed and Fixed-Satellite Services
[3-1](#fixed-and-fixed-satellite-services)

3.3 Radiodetermination and Radiodetermination-Satellite Services
[3-1](#radiodetermination-and-radiodetermination-satellite-services)

3.4 Broadcasting and Broadcasting-Satellite Services
[3-2](#broadcasting-and-broadcasting-satellite-services)

3.5 Mobile and Mobile-Satellite Services
[3-2](#mobile-and-mobile-satellite-services)

3.6 Science Services [3-3](#science-services)

Section 4 FIXED AND FIXED-SATELLITE SERVICES
[4-1](#fixed-and-fixed-satellite-services-1)

4.1 INTRODUCTION [4-1](#introduction-3)

4.2 FIXED SERVICE [4-1](#fixed-service)

4.2.1 General [4-1](#general)

4.2.2 System Characteristics and Performance Objectives
[4-1](#system-characteristics-and-performance-objectives)

4.2.3 Interference Protection Criteria
[4-3](#interference-protection-criteria)

4.2.4 Possible Mitigating Factors [4-8](#possible-mitigating-factors)

4.3 FIXED-SATELLITE SERVICE [4-9](#fixed-satellite-service)

4.3.1 General [4-9](#general-1)

4.3.2 System Characteristics and Performance Objectives
[4-9](#system-characteristics-and-performance-objectives-1)

4.3.3 Error Performance Objective [4-11](#error-performance-objective)

4.3.4 Interference Protection Criteria Summary
[4-14](#interference-protection-criteria-summary)

4.4 SUMMARY [4-16](#summary)

Section 5 RADIODETERMINATION AND RADIODETERMINATION-SATELLITE SERVICES
[5-1](#radiodetermination-and-radiodetermination-satellite-services-1)

5.1 Introduction [5-1](#introduction-4)

5.2 Radiodetermination Service [5-1](#radiodetermination-service)

5.2.1 Radars operated in the Radiolocation, Aeronautical
Radionavigation, Meteorological Aids, and Maritime Radionavigation
Services
[5-1](#radars-operated-in-the-radiolocation-aeronautical-radionavigation-meteorological-aids-and-maritime-radionavigation-services)

5.2.2 CW and Noise-like Interfering Signals
[5-2](#cw-and-noise-like-interfering-signals)

5.2.3 Pulse-Like Interfering Signals
[5-3](#pulse-like-interfering-signals)

5.2.4 Impulse-Like Interfering Signals
[5-3](#impulse-like-interfering-signals)

5.2.5 Aeronautical Radionavigation Systems (other than radars using
passive reflections)
[5-4](#aeronautical-radionavigation-systems-other-than-radars-using-passive-reflections)

5.3 RadioNAVIGATION-Satellite Service
[5-5](#radionavigation-satellite-service)

5.3.1 IPC Values for GPS Receivers [5-6](#ipc-values-for-gps-receivers)

Section 6 BROADCASTING AND BROADCASTING-SATELLITE SERVICES
[6-1](#broadcasting-and-broadcasting-satellite-services-1)

6.1 Introduction [6-1](#introduction-5)

6.2 Broadcasting Service [6-1](#broadcasting-service)

6.2.1 Broadcast Television [6-2](#broadcast-television)

6.2.2 FM Radio Broadcast [6-7](#fm-radio-broadcast)

6.3 Broadcasting-Satellite Service
[6-9](#broadcasting-satellite-service)

6.3.1 Appendix 30 (AP30) of the ITU Radio Regulations
[6-11](#appendix-30-ap30-of-the-itu-radio-regulations)

6.3.2 Recommendation ITU-R BO.1297 [6-13](#recommendation-itu-r-bo.1297)

6.3.3 Recommendation ITU-R BO.1444 [6-13](#recommendation-itu-r-bo.1444)

6.3.4 FCC Report and Order 00-418 [6-14](#fcc-report-and-order-00-418)

6.3.5 Mitre Technical Report [6-14](#mitre-technical-report)

6.3.6 Spectrum XXI [6-15](#spectrum-xxi)

6.3.7 Further Study [6-15](#further-study)

6.4 SUMMARY [6-16](#summary-1)

Section 7 MOBILE AND MOBILE SATELLITE SERVICEs
[7-1](#mobile-and-mobile-satellite-services-1)

7.1 Introduction [7-1](#introduction-6)

7.2 Mobile Service [7-1](#mobile-service)

7.2.1 Mobile Service in General [7-1](#mobile-service-in-general)

7.2.2 Land Mobile Service [7-3](#land-mobile-service)

7.2.3 Maritime Mobile Service [7-5](#maritime-mobile-service)

7.2.4 Aeronautical Mobile Service [7-6](#aeronautical-mobile-service)

7.3 Mobile Satellite Service [7-7](#mobile-satellite-service)

7.3.1 Geostationary Satellite Service
[7-7](#geostationary-satellite-service)

7.3.2 Nongeostationary Satellite Service - Downlink
[7-8](#nongeostationary-satellite-service---downlink)

7.3.3 NGSO Satellite Service (Cospas-Sarsat Uplink)
[7-8](#ngso-satellite-service-cospas-sarsat-uplink)

7.4 Summary [7-8](#summary-2)

Section 8 SCIENCE SERVICES [8-1](#science-services-1)

8.1 INTRODUCTION [8-1](#introduction-7)

8.2 SPACE RESEARCH SERVICE [8-1](#space-research-service)

8.2.1 Deep-Space Research [8-1](#deep-space-research)

8.2.2 Near Earth Space Research [8-3](#near-earth-space-research)

8.2.3 Data Relay Satellites [8-4](#data-relay-satellites)

8.2.4 Telecommunication Links in the 37-40 GHz Bands
[8-4](#telecommunication-links-in-the-37-40-ghz-bands)

8.3 SPACE OPERATION SERVICE [8-5](#space-operation-service)

8.4 METEOROLOGICAL AIDS [8-5](#meteorological-aids)

8.5 EARTH EXPLORATION-SATELLITE AND METEOROLOGICAL SATELLITE SERVICES
[8-6](#earth-exploration-satellite-and-meteorological-satellite-services)

8.5.1 Space-to-Earth Data Transmission Systems Using Low-Earth Orbit
[8-6](#space-to-earth-data-transmission-systems-using-low-earth-orbit)

8.5.2 Data Dissemination and Direct Data Readout Systems Using
Geostationary Satellites
[8-7](#data-dissemination-and-direct-data-readout-systems-using-geostationary-satellites)

8.5.3 Service Links in Data Collection Systems
[8-7](#service-links-in-data-collection-systems)

8.5.4 Command and Data Transmission System
[8-7](#command-and-data-transmission-system)

8.5.5 Satellite Passive Remote Sensing
[8-8](#satellite-passive-remote-sensing)

8.5.6 Spaceborne Active Microwave Remote Sensors
[8-8](#spaceborne-active-microwave-remote-sensors)

8.6 RADIO ASTRONOMY [8-9](#radio-astronomy)

8.7 SUMMARY [8-10](#summary-3)

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#  INTRODUCTION

## BACKGROUND

The National Telecommunications and Information Administration (NTIA) is
the Executive Branch agency responsible for developing and articulating
domestic and international telecommunications policy. NTIA acts as the
principal advisor to the President on telecommunications policies
pertaining to the nation's economic and technological advancement and
regulation of the telecommunications industry. NTIA is also responsible
for managing the federal government's use of the radio spectrum. Federal
agencies are highly dependent on interference-free spectrum access to
support a wide variety of critical missions including weather
forecasting and homeland security.

The spectrum management process, originally established under the
Communications Act of 1934,has been frequently faced with rapidly
changing perceived spectrum requirements of both the private sector and
the federal government. The Federal Communications Commission (FCC), and
NTIA have coordinated their spectrum management efforts to ensure that
policies, rules, and practices for spectrum usage adequately prevent
interference.

One of the primary goals in spectrum management is to plan, allocate and
assign spectrum in a way that prevents interference. This goal was
discussed at NTIA's April 2002 Spectrum Summit of the federal and
private sector spectrum management community as well as the radio
service users and providers. In parallel, the FCC created a Spectrum
Policy Task Force (SPTF) that focused on a number of issues, including
interference, and formed an Interference Protection Working Group
(IPWG). This forum posed several relevant questions. For example, how
does one determine whether interference is harmful? What are the
property rights of the licensed or assigned user? What are the property
rights relative to freedom from interference? Many participants
indicated that answers need to be developed with a clear view of the
necessary spectrum management policies and conditions under which
interference will be prevented.

On June 6, 2002, the FCC SPTF issued a public notice seeking comment on
issues related to the FCC's spectrum policies.[^1] The IPWG held several
public workshops where the public was invited to present input. Over
forty-eight companies provided comments on interference protection,
suggesting that both licensed and unlicensed spectrum users should have
clearly defined rights and obligations relating to interference.
Participants also suggested that the United States integrates its
domestic and international spectrum policy efforts on interference and
concluded that interference protection was at the heart of many
contentious debates before the FCC and NTIA. Furthermore, commenters
suggested that both agencies should recognize and address several key
interference principles:[^2]

-   some level of interference can be tolerated, which varies depending
    on the nature of the service involved and the nature of the
    interference;

-   due to advances in digital signal processing and antenna technology,
    communications systems and devices are becoming more tolerant of
    interfering signals through their ability to sense and adapt to the
    RF environment;

-   all systems require some degree of margin to ensure reliable
    communications; the regulators should not assume that eliminating
    that margin is acceptable;

-   the regulations and practices of interference protection differ
    between different radio services, with the rules of some services
    prescribing detailed criteria for predicting interference;

-   the regulators should consider interfering signal aggregation of
    multiple sources;

-   harmful interference is an extreme level and that just because
    interference does not rise to that level, it cannot be concluded
    that the interference is acceptable to the victim; and

-   the FCC should make clear that its spectrum policies are based on an
    "interference-limited" rather than "ambient noise-limited"
    environment.

The SPTF provided a report of its findings and recommendations to the
FCC in November 2002.[^3]

In the last five to ten years, spectrum usage and demand have increased
significantly. The major interference issues have required a substantial
time to define and resolve. For example, in adopting rules for
implementing the new technology referred to as ultrawideband (UWB), it
took several years to obtain measurement and analytical information on
interference susceptibility, sufficient to define the necessary
Interference Protection Criteria (IPC). In order to accommodate new
technologies and additional licensed and/or unlicensed operations more
quickly, advocates, incumbents and regulators will have to find better
ways to analyze the interference potential. Moreover, system designers
need guidance on the levels of interfering signals that should be
tolerated. To this end, it is appropriate to further define IPC.

The identification of the appropriate IPC is often a confusing,
time-consuming process that is not supported by a single reference
source. This process is further complicated by numerous relevant
regulatory and technical terms. For example, the NTIA, FCC, and the
International Telecommunication Union, Radiocommunication Sector,
(ITU-R) define several terms relative to interference, including:
*Interference, Permissible Interference, Accepted Interference, Harmful
Interference,* and *Protection Ratios.* Other terms that are commonly
used, but not specifically defined are: *Allowable Performance
Degradation, Interference Protection Criteria,* and *Spectrum Sharing
Criteria*. Furthermore, since spectrum-sharing criteria normally depend
upon parameters of both the interfering and interfered-with systems and
their operating environments, a very large number of combinations is
possible. Consideration of interference is "at least a six dimensional
problem, meaning spatial, x-y-z, frequency, time, and waveform, and of
course since the waveform can be infinitely complicated, you can make it
an n-fold problem, which basically has more variables than you have
numbers."[^4]

In 1990, International Telecommunication Union, Radiocommunication
sector, Study Group 1 attempted to reduce this complexity by adopting
Rec. ITU-R SM.669 that includes a matrix of protection ratios for
various combinations of interfering and desired-signal modulation
types.[^5] An earlier, but more comprehensive approach was undertaken
jointly by NTIA and the Department of Defense (DOD) Joint Spectrum
Center (JSC), resulting in the publication of the Communications
Receiver Performance Degradation Handbook.[^6] However, the IPC
presented in Rec. ITU-R SM.669 as well as the Degradation Handbook have
become largely obsolete for several reasons, including:

1)The Degradation Handbook and Rec. ITU-R SM.669 focus on analog and
early digital modulations, which are in many cases being supplanted by
more complex, digital modulations.

2\) Both efforts focused primarily on modulation with little regard to
radio service requirements or factors stemming from the operating
frequency, whereas most spectrum sharing studies today focus primarily
on radio services and specific frequency bands.

3\) The IPC in these texts do not include temporal or spatial
statistical allowances that should be considered in detailed analyses.

Since the adoption of Rec. ITU-R SM.669 and completion of the
Degradation Handbook, extensive spectrum sharing studies have been
completed and documented within the International Telecommunication
Union, Radiocommunication sector, and elsewhere. As part of on-going
spectrum sharing studies within the International Telecommunication
Union, Radiocommunication sector, the various service study groups have
refined and documented IPC for their respective radio services within
numerous International Telecommunication Union, Radiocommunication
sector Recommendations. In light of these developments, NTIA launched a
study of IPC. This Phase 1 report compiles available IPC. In the second
phase of this study, NTIA will review the relevant federal government
policy and practices regarding derivation of IPC, and recommend
regulatory and technical refinements that may improve IPC application's
scope, utility, clarity, or effectiveness.

## OBJECTIVE

The National Telecommunications and Information Administration (NTIA)
launched a two-phase study of interference protection criteria (IPC) to
compile, explain and validate, modify or supplement the levels of
protection from interference that are generally expected and provided
for various radiocommunication systems.

The study is an integral part of President Bush's Spectrum Policy
Initiative that was established in May 2003 to promote the development
and implementation of a United States spectrum policy for the 21st
century. The Secretary of Commerce then established a Federal Government
Spectrum Task Force and initiated a series of public meetings to address
improvements in policies affecting spectrum use by the Federal
Government, State, and local governments, and the private sector. The
recommendations resulting from these activities were included in a
two-part series of reports released by the Secretary of Commerce in June
2004, under the title *Spectrum Policy for the 21st Century - The
Presidents Spectrum Policy Initiative*. Based on the recommendations
contained in these Reports, the President directed the federal agencies
on November 30, 2004, to plan the implementation of the 24
recommendations contained in the Reports. There were several
recommendations that will consider the interference protection criteria
contained in this study including:

-   assessment of new technologies and their impact on incumbent
    radiocommunications;

-   managing interference;

-   development of a "Best Practices Handbook" for spectrum engineering;

-   establishment a pilot program and long-range plan for improved
    sharing of spectrum between federal and non-federal entities; and

-   creation of new analytical computer models that will facilitate
    spectrum engineering.

Based on the above, the objectives of this study are as follows:

> Phase 1:

-   Review publicly available texts to identify and document IPC for
    radio services that accommodate federal government
    radiocommunications and apply this information as applicable to the
    completion of the appropriate recommendations approved by President
    Bush.

> Phase 2:

-   Review federal government policy and practices regarding IPC and
    recommend regulatory refinements that may improve the scope, clarity
    or effectiveness of interference-protection provisions, as
    appropriate;

-   Review applications for IPC;

-   Develop a methodology for determining appropriate IPC that can be
    used to supplement, validate or refine existing IPC;

Additional objectives will be determined during Phase 2 of this study.
These may include:

-   Apply the methodology for determining appropriate IPC to supplement
    or refine, as appropriate, IPC identified in Phase 1 to establish
    validated IPC for each radio service;

-   Incorporate findings in NTIA's planned best practices handbook;

-   On a case-by-case basis, promote IPC and associated regulatory
    provisions for the private sector through rulemakings at the FCC;

-   Provide the results to ITU-R Study Group 1 for possible replacement
    of Rec. ITU-R SM.669.

## PHASE 1 APPROACH

-   Define IPC.

-   Compile IPC in five broad areas covering fixed and fixed-satellite
    services, radiodetermination and radiodetermination-satellite
    services, broadcasting and broadcasting--satellite services, mobile
    and mobile-satellite services, and science services.

-   Categorize IPC according to the type of interfering signal
    (continuous wave (CW), noise-like, pulse, and other) and, where
    available, associated statistical allowances (long-term or
    short-term).

-   Document results in an NTIA Phase 1 report.

## SCOPE

This report includes IPC covering the frequency range 30 MHz to 30 GHz.
Numerous sources of IPC are available from international agencies,
government agencies, trade associations, academic institutions, and
others. This report compiles IPC from generally accepted sources. The
sources considered were as follows:

-   ITU-R. A role of the ITU-R is to provide guidance for the rational,
    equitable, efficient, and economical use of the radio-frequency
    spectrum by all radiocommunication services. The ITU-R carries out
    studies culminating in Recommendations, which serve as a repository
    of technical and procedural guidelines for the design,
    implementation and operation of radiocommunications systems. The
    ITU-R Study Groups (SG) listed below focus on particular
    radiocommunications services, as do the subsequent sections of this
    report. Working parties are established within each Study Group to
    address service issues such as performance objectives.

```{=html}
<!-- -->
```
-   SG 1 - Spectrum management

-   SG 3 - Radiowave propagation

-   SG 4 - Fixed-satellite service

-   SG 6 - Broadcasting service

-   SG 7 - Science services

-   SG 8 - Mobile, radiodetermination, amateur and related satellite
    services

-   SG 9 - Fixed service

```{=html}
<!-- -->
```
-   International Civil Aviation Organization (ICAO). One of the chief
    activities of the ICAO is the establishment of International
    Standards, Recommended Practices and Procedures covering the
    technical fields of aviation including aeronautical
    telecommunications, air traffic services, search and rescue,
    navigation, surveillance, and aeronautical information services. The
    principle document considered herein is the ICAO International
    Standards and Recommended Practices.

-   International Maritime Organization (IMO). The IMO was established
    with the chief task of developing a comprehensive body of the
    international conventions, codes and recommendations to be
    implemented by all member governments. The Maritime Safety Committee
    has sub-committees dealing with relevant subjects, including safety
    of navigation, radiocommunications and search and rescue.

-   International Electrotechnical Commission (IEC). The IEC is a global
    organization that prepares and publishes international standards for
    all electrical, electronic and related technologies. These serve as
    a basis for national standardization and as references when drafting
    international tenders and contracts.

-   World Meteorological Organization (WMO). The WMO coordinates global
    scientific activity to allow increasingly prompt and accurate
    weather information services for public, private and commercial use,
    including international airline and shipping industries. WMO\'s
    major scientific and technical programs include the World Weather
    Watch, which offers up-to-the-minute world-wide weather information
    through member-operated observation systems and telecommunication
    links (presently using four polar-orbiting and five geostationary
    satellites, about 10,000 land observation stations, 7,000 ship
    stations and 300 moored and drifting buoys carrying automatic
    weather stations).

-   European Radiocommunications Organization (ERO). ERO is the
    permanent office supporting the Electronic Communications Committee
    (ECC) of the European Conference of Postal and Telecommunications
    Administrations (CEPT). ECC is the Committee that brings together
    the radio and telecommunications regulatory authorities of the 45
    CEPT member countries.

-   National Telecommunications and Information Administration (NTIA).
    NTIA is the Executive Branch agency principally responsible for
    developing and articulating domestic and international
    telecommunications policy as well as managing and regulating federal
    government use of the spectrum. Accordingly, NTIA conducts studies
    and makes recommendations regarding telecommunications matters to
    Congress, the FCC, and the public. NTIA rules and publications
    include the NTIA Manual and the library of reports produced by the
    Office of Spectrum Management (OSM) and the Institute for
    Telecommunication Sciences (ITS).[^7]

-   Federal Communications Commission (FCC). The FCC manages and
    regulates use of the spectrum by non-federal entities. The FCC rules
    and regulations are codified in Title 47 of the Code of Federal
    Regulations (CFR).

-   Joint Spectrum Center (JSC). JSC conducts various frequency sharing
    studies for the Department of Defense (DOD). The Joint Staff J-6 of
    DoD directed the JSC to develop Spectrum XXI as a Windows-NT based
    application to address the spectrum management requirements of the
    Force Commanders, the Joint Task Force (JTF) commanders, the
    Military Departments, and the sustaining base elements. Spectrum XXI
    uses a table containing IPC for many services that is based on NTIA
    reports, FCC Rules and Regulations, ITU-R Recommendations and
    Reports, the DOD/JSC Degradation Handbook, and industry standards.

-   Military Standards (MIL-STDs). MIL-STDs generally impose
    requirements and instructions on the military. They are written
    primarily for the benefit of program offices and product centers.
    Compliance may not be mandatory. MIL-STDs were found through
    searching the DOD Index of Specifications and Standards (DODISS).

-   RTCA Inc. (formallyTechnical Commission on Aeronautics). The RTCA
    Inc., is an association of aeronautical organizations from the
    United States and other countries that seeks sound technical
    solutions to problems involving the application of electronics and
    telecommunications to aeronautical operations.

-   Radio Technical Commission on Maritime (RTCM). The RTCM is chartered
    in the District of Columbia, as a non-profit scientific and
    educational organization, focusing on all aspects of maritime
    radiocommunications, radionavigation, and related technologies.
    Participants are from government and private sectors. Since its
    establishment in 1946, the RTCM has been supported by its member
    organizations to serve as a focal point to collect and distribute
    information, and to serve as a catalyst in developing solutions to
    both national and international maritime radiocommunications and
    radionavigation issues.

-   Telecommunications Industry Association (TIA). TIA, in conjunction
    with the Electronics Industry Alliance (EIA), sponsors committees of
    experts to prepare standards dealing with performance testing and
    compatibility. TIA is accredited by the American National Standards
    Institute (ANSI) to develop voluntary industry standards for a wide
    variety of telecommunications products.

-   Aerospace and Flight Test Radio Coordinating Council (AFTRCC).
    AFTRCC provides recommendations to the FCC for non-government use of
    flight test voice and telemetry frequencies. Its role is strictly
    advisory.

-   Association of Public-Safety Communications Officials (APCO). APCO
    is an international non-profit professional organization dedicated
    to the enhancement of public safety communications. It serves the
    people who manage, operate, maintain, and supply public safety
    communications systems mainly at the state level.

-   Institute of Electrical and Electronics Engineers (IEEE). IEEE is a
    non-profit, technical professional association in 150 countries. The
    IEEE is a leading authority in technical areas such as computer
    engineering and telecommunications. Through its technical
    publishing, conferences and consensus-based standards activities,
    IEEE produces 30 percent of the world\'s published literature in
    electrical engineering, computers and control technology, holds
    annually more than 300 major conferences and has nearly 900 active
    standards with 700 under development.

-   The European Telecommunications Standards Institute (ETSI). ETSI is
    the technical standards body under the European Conference of Postal
    and Telecommunications Administrations (CEPT). It publishes European
    technical standards that are adopted by most regulatory authorities
    in Europe as well as in some non-European countries. Having common
    standards facilitates equipment testing and type acceptance in these
    countries.

-   United Kingdom Radiocommunications Agency (RA). RA was an executive
    agency of the Department of Trade and Industry, United Kingdom. It
    was responsible for the management of the non-military radio
    spectrum in the United Kingdom, which involves international
    representation, commissioning research, allocating spectrum and
    licensing its use. Recently, office of communicatons (OFCOM), has
    taken over these responsibilities and assumed the powers of the five
    former regulators it has replaced - the Broadcasting Standards
    Commission, the Independent Television Commission, OFTEL, the Radio
    Authority and the Radiocommunications Agency. OFCOM is the regulator
    for the United Kingdom communications industries, with
    responsibilities across television, radio, telecommunications and
    wireless communications services.

-   Eurocontrol. Eurocontrol is an organization consisting of 41
    European states whose mission is to co-ordinate the development of a
    uniform system of air traffic management throughout Europe.
    Eurocontrol works with its members in the air transport industry to
    provide a range of services, including air traffic controller
    training; managing air traffic flow; regional control of airspace to
    development of innovative technologies and procedures; and
    collection of air navigation charges, civil/military among other
    things.

REFERENCES

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#  {#section .unnumbered}

#  TECHNICAL perspectives 

## INTRODUCTION

This section provides an overview definitions and relevant terms related
to interference and IPC.

## Relevant Definitions

The ITU Radio Regulations (Article 1), NTIA Manual (Chapter 6), and FCC
Rules and Regulations (Part 2), define several terms related to
interference, including:[^8]

**1.166**

***Interference**:* The effect of unwanted energy due to one or a
combination of *emissions*,

*radiations*, or inductions upon reception in a *radiocommunication*
system, manifested by any performance degradation, misinterpretation, or
loss of information which could be extracted in the absence of such
unwanted energy.

**1.167**

***Permissible Interference**:* Observed or predicted *interference*
which complies with

quantitative *interference* and sharing criteria contained in these
Regulations or in ITU-R

Recommendations or in special agreements as provided for in these
Regulations.

**1.168**

***Accepted Interference**: Interference* at a higher level than that
defined as *permissible*

*interference* and which has been agreed upon between two or more
administrations without prejudice to other administrations.

**1.169**

***Harmful Interference**: Interference* which endangers the functioning
of a *radionavigation service* or of other *safety services* or
seriously degrades, obstructs, or repeatedly interrupts a
*radiocommunication service* operating in accordance with these
Regulations (CS).

**1.170**

***Protection Ratios (R.F.)**:* The minimum value of the
wanted-to-unwanted signal ratio, usually expressed in decibels, at the
receiver input determined under specified conditions such that a
specified reception quality of the wanted signal is achieved at the
receiver output.

The following terms are not formally defined in any regulatory
documents. These terms have been in common use, in NTIA.

-   ***Allowable Performance Degradation***: Agreed upon degradation in
    the performance of a radiocommunication system due to interference
    that is at a sufficiently low level such that the performance
    capabilities are not significantly compromised. This is often
    defined in terms of a percentage change in a key performance measure
    such as voice circuit noise, outage time, or target detection
    probability.

-   ***Interference Protection Criteria (IPC)***: A relative or absolute
    interfering signal level defined at the receiver input, under
    specified conditions, such that the allowable performance
    degradation is not exceeded. This is usually defined as an absolute
    interference power level I, interference-to-noise power ratio I/N,
    or carrier-to-interfering signal power ratio C/I.

-   ***Sharing Criteria***: Broadly defined criteria that ensure
    compliance with IPC by specifying technical and operational
    constraints that permit sharing of a given portion of the spectrum
    between two or more radio systems or services.

## Elements of Interference Protection Criteria

All of the IPC compiled herein specify permissible interference. IPC are
specified for aggregate interfering signals (i.e., total from all
interferers) or single-entry interfering signals (i.e., from one
interfering system). Aggregate IPC are generally derived from
performance objectives and may be used to define the potential
interfering signal environment in system design or performance analyses.
Single-entry IPC, in turn, are derived from aggregate IPC and are used
as "spectrum sharing criteria" directly or as the basis for other forms
of sharing criteria (e.g., transmitter power and antenna pointing
limits).

IPC for many services are quite dependent upon the specific type of
interfering signal received. Nevertheless, a relatively small number of
generic classes of interfering signal modulation can define bounding
situations. These bounding cases include continuous wave (CW),
noise-like, and pulse. For some services, interfering signals
characterized as "impulse" and "same as desired signal" are included.
Additionally, for some radio services, "short-term" and "long-term" IPC
are specified. Table 2-1 summarizes these categories.

IPC are generally given in terms of (C/I) ratios or power (I/N) ratios.
The former defines the interfering signal level relative to a known
carrier level, whereas the latter defines the level of interfering
signal level relative to the system noise level. Some IPC directly
specify interfering signal power levels.

**Table 2-1**

Interfering Signal Types Typically Specified With IPC

  ----------------- -----------------------------------------------------
  Type of           Definition
  Interfering       
  Signal            

  Continuous Wave   A continuous signal with a bandwidth much smaller
  (CW)              than the receiver baseband (output) bandwidth.

  Noise-Like        A continuous signal that resembles Gaussian white
                    noise over the RF bandwidth of the receiver (uniform
                    power spectral density) or produces the same effect
                    as such a signal.

  Pulse             A signal that is turned on and off over time and can
                    be described in terms of a pulse width and pulse
                    repetition rate. The pulses may occur with a constant
                    or changing repetition rate.

  Impulse           A pulsed signal having a very short pulse width
                    (often much less than a microsecond). In general, any
                    pulsed signal having a pulse width much smaller than
                    the impulse response of the receiver bandpass under
                    consideration can be considered as an impulse signal.

  Same as Desired   All signal modulation parameters are the same as the
  Signal            desired signal except baseband information content
                    (carrier frequencies may differ).

  Long-Term         Interfering signal levels that are present most of
                    the time, e.g., levels not exceeded for more than 80%
                    of the time.

  Short-Term        Interfering signal levels that are rarely exceeded,
                    e.g., levels not exceeded for more than 99.9% of the
                    time.
  ----------------- -----------------------------------------------------

For a given service and type of system, IPC must include the parameters
listed in Table 2-2 in order to rigorously define the intended degree of
protection from interference and enable application of the IPC with
detailed, statistical analysis models. Omission of any of the parameters
comprising complete IPC may prevent proper analysis of potential
interference or performance and could yield less or more than the
intended degree of protection.

**Table 2-2**

Parameters Needed to Fully Specify Aggregate

and Single-Entry IPC

+------------+-------+-------------------------------------------------+
| IPC        | Ty    | Description                                     |
|            | pical |                                                 |
| Parameter  |       |                                                 |
|            | Units |                                                 |
+------------+-------+-------------------------------------------------+
| Power      | dBm,  | One or more levels of interfering signal power  |
|            |       | I, I/N, or C/I.                                 |
| Threshold  | dBW,  |                                                 |
|            |       |                                                 |
|            | dB    |                                                 |
+------------+-------+-------------------------------------------------+
| Reference  | Hz,   | Bandwidth in which interfering signal power     |
|            | kHz,  | should be calculated or measured.               |
| Bandwidth  |       |                                                 |
|            | MHz   |                                                 |
+------------+-------+-------------------------------------------------+
| Percentage | \%    | For each threshold, the percentage of time      |
|            |       | during which the threshold should (C/I) or      |
| of Time    |       | should not (I or I/N) be exceeded.              |
+------------+-------+-------------------------------------------------+
| Percentage | \%    | For each threshold, the percentage of locations |
|            |       | at which the threshold should (C/I) or should   |
| of         |       | not (I or I/N) be exceeded. Used in some        |
| Locations  |       | services to protect operations within a service |
|            |       | area.                                           |
+------------+-------+-------------------------------------------------+
| Special    | va    | Information needed for interpretation or        |
|            | rious | application of the thresholds, including as a   |
| Conditions |       | minimum: whether the IPC are for aggregate or   |
|            |       | single-entry interference; the type of          |
|            |       | interfering signal (e.g., noise-like) for which |
|            |       | the IPC apply; and for I/N and C/I thresholds   |
|            |       | the definition of the N or C reference levels.  |
|            |       | May include duration of permissible threshold   |
|            |       | exceedance (e.g, \# seconds); specific category |
|            |       | of victim or interfering stations; and          |
|            |       | frequency off-tuning associated with the        |
|            |       | thresholds.                                     |
+------------+-------+-------------------------------------------------+

REferences

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#  OVERVIEW

## INTRODUCTION

This section contains an overview of the detailed findings presented in
Sections 4 through 8. At the end of each of these sections, a table
presents a summary of the IPC values.

## Fixed and Fixed-Satellite Services

Section 4 presents the IPCs for fixed services (FS) and fixed-satellite
services (FSS) with a focus on digital modulation. For the FS, the
discussion includes system characteristics and performance objectives of
point-to-point, line-of-sight, digital microwave systems (DMS) and IPC
values that have been adopted nationally or internationally. The
technical parameters of DMS vary over a wide range and cannot be simply
characterized. The performance of DMS is generally defined in terms of
error performance and availability objectives. DMS are designed to
achieve very low bit error ratios with typical per hop availability of
99.999% and higher. As a general rule, IPC values have been developed
based on limiting performance degradation due to interference to a small
percentage of the design objective values. IPC values for DMS are
generally defined in ITU-R Recommendations in terms of I/N, whereas TIA
Bulletins and FCC Regulations define the IPC in terms of C/I. For DMS,
IPC values are presented in three categories: long-term CW and
noise-like interfering signals, short-term CW and noise-like interfering
signals, and pulse interfering signals.

For FSS, the discussion first presents representative FSS system
characteristics and IPC defined in ITU-R texts for purposes of
triggering frequency coordination. Then the desired signal qualities,
specified in the form of error performance requirements, are discussed.
The IPC are specified as an apportionment of the total noise allowance,
while the total noise allowance is indirectly specified as the error
performance requirement. Aggregate and single-entry IPC for both
long-term and short-term interfering signal levels are given.

## Radiodetermination and Radiodetermination-Satellite Services

Section 5 specifies IPC for systems operating in the radiodetermination
and radionavigation satellite services in terms of an I/N, S/I, or
interfering signal power level (I). The ITU has developed Part 4 of the
M series of ITU-R Recommendations that contain the IPC for radars that
rely on reflections or scattering from targets to perform their mission.
These IPC are based on CW-like and noise-like interfering signals.

IPC do not consider the statistical nature of the interfering signal
power levels and they do not differentiate between long and short-term
interfering signal levels. Systems that employ a data link or a
transponder have IPC based on an S/I or I forms of IPC. These IPC come
from national and international aviation advisory committees. The IPC
for these systems tends to be more conservative because they are
intended to protect aircraft flight and landing operations under
unfavorable circumstances. Depending on the system, the IPC can be for
CW, noise, or pulse-like interfering signals.

IPC for radionavigation satellite service (RNSS) were developed to
protect receivers that are designed to use the Global Positioning System
(GPS) and the Global Navigation Satellite System (GLONASS) operated by
the United States, DOD and the Russian Federation to obtain position
fixes and timing information. The ITU has developed IPC in the form of I
levels for both GPS and GLONASS receivers that are contained in Part 5
of the M series of ITU-R Recommendations. The RTCA has developed IPC for
aviation GPS receivers that are also based on I criteria.

## Broadcasting and Broadcasting-Satellite Services

Section 6 discusses IPC for broadcasting services (BS) and the
broadcasting-satellite services (BSS). The BS involves radio or
television transmissions from terrestrial stations for direct reception
by the general public. IPC for television are contained primarily in
ITU-R Recommendations and FCC Rules. IPC for digital television apply to
continuous and/or tropospheric interfering signals. These continuous
interfering signals are long-term interfering signals at levels that are
not exceeded for a large percentage of the time (e.g., 50%) and
generally serve as the baseline for establishing protection criteria.
Tropospheric interfering signals are short-term interfering signals at
levels exceeded for no more than 1% to 10% of the time.

FCC Rules addressing Frequency Modulation (FM) radio broadcasting define
sharing criteria between FM radio stations in terms of minimum distance
separations and do not specify general IPC values. IPC are given for
interference between Very High Frequency (VHF) television channel 6 and
FM radio broadcasting as well as between public safety (land mobile
service) and television broadcasting.

IPC for BSS systems are in the forms of C/I, I/N, or power flux density
(pfd). They are found primarily in international texts. IPC are listed
for both co-channel and adjacent channel interfering signal sources. In
some cases, the adjacent channel IPC are a linear function of carrier
frequency offset. IPC are specified for BSS service links
(space-to-Earth) and their associated feeder links (Earth-to-space). The
majority of IPC are for long-term interference protection although
statistical approaches are being developed to provide short-term IPC.

## Mobile and Mobile-Satellite Services

Section 7 discusses the IPC for mobile service (MS) and mobile-satellite
service (MSS). The MS includes land mobile, maritime mobile, and
aeronautical mobile services. IPC values provided for the MS in this
document have been adopted nationally or internationally. They cannot be
characterized simply since the majority of these IPC vary depending on
the reference and do not contain all of the parameters required to fully
define IPC (e.g., the percentage of time that an interfering signal
level can be exceeded, type of interfering signal, single-entry versus
aggregate). Most of the IPC are for co-channel operations.

For land mobile applications, TIA Telecommunications Systems Bulletin
(TSB) 88-A provides a methodology to determine IPC in terms of the
carrier-to-interference-plus-noise power ratio (C/(I+N)) needed for
satisfactory voice applications. Specifically, IPC for different desired
signal modulation types may be calculated based on the power spectrum of
the given signal modulations and Intermediate Frequency (IF) filter
selectivity as well as the C/N required to fulfill the specific Channel
Protection Criterion (CPC). TIA is currently developing IPC that could
be applicable to data applications. A limited number of IPC values are
available for the maritime and aeronautical services.

For the MSS, the only source found for IPC is the ITU-R M series of
Recommendations. ITU-R does not have MSS IPC specifications for analog
desired signals. For MSS systems using the geostationary orbit, IPC are
specified as an apportionment of the total noise, while the total noise
is indirectly specified as the error performance requirement. For
digital signals of MSS systems using non-geostationary orbits, IPC are
specified in terms of the maximum aggregate interfering signal level at
the input of the receive antenna, and the IPC values depend on the type
of service, earth station antenna size, modulation, reference bandwidth,
and access method.

## Science Services

Section 8 discusses IPC for science services. Science services include
the space research service, inter-satellite service, space operations,
meteorological aids service, Earth exploration-satellite (EES) service,
meteorological-satellite (METSAT) service, and radio astronomy. These
services support various missions including manned space flights and
routine data collection. IPC for science services vary widely and are
specified in ITU-R Recommendations.

IPC for science services are generally given as the power spectral
density for noise-like interfering signals or the total power of CW
interfering signals at the receiver terminals in a specified frequency
band. In some cases, both long-term and short-term IPC values are
specified. In the case of radio astronomy, IPC are given in the form of
power flux density.

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#  FIXED AND FIXED-SATELLITE SERVICES

## INTRODUCTION

The IPC for fixed services (FS) and fixed-satellites service (FSS) have
been extensively studied and are well documented in the ITU-R
Recommendations (S, F and SF Series) and publications issued by the TIA
and others. As previously discussed, key factors that influence the
establishment of IPC values include: emission type, allocation status of
the interferer, and the duration of the interfering signal. This section
discusses IPC for the FS and FSS with a focus on digital modulation.

## FIXED SERVICE

### General

This sub-section addresses systems in the FS, specifically
point-to-point DMS. The following paragraphs discuss source documents
defining FS characteristics and performance objectives that are
associated with IPC values that have been adopted nationally or
internationally. Within this sub-section, all interfering signal power
levels are based on the average power unless explicitly stated as peak
power.

### System Characteristics and Performance Objectives

The technical parameters of DMS vary over a wide range and cannot be
simply characterized even within a given frequency band. Typical
parameters and characteristics for DMS operating in bands from 800 MHz
to 52 GHz are described in Appendix 7 of the ITU-R Radio Regulations
Rec. ITU-R/ F.758, F.1101, F.1102 and TIA-TSB 10-F.[^9] Appendix 7 of
the ITU-R Radio Regulations applies the values shown in Table 4-1 for
certain DMS receiver parameters that are used in determination of
coordination distances between transmitting earth stations and DMS.

**Table 4-1**

FS DMS Default Values in Appendix 7 of ITU-R Radio Regulations

+-----------+--------+-----------+----------+-----------+----------+
| Band      | R      | Noise     | Fade     | Int       |          |
|           | eceive | Temper    | Margin   | erference |          |
| (GHz)     | A      | a-ture^i^ | (dB)     | Cri       |          |
|           | ntenna | (K)       |          | teria^ii^ |          |
|           | Gain   |           |          |           |          |
|           | (dBi)  |           |          |           |          |
+-----------+--------+-----------+----------+-----------+----------+
|           |        |           |          | I ^iii^   | Percent  |
|           |        |           |          | (dBW/MHz) | of Time  |
|           |        |           |          |           | (%)      |
+-----------+--------+-----------+----------+-----------+----------+
| 1.4       | 33     | 750       | 33       | --107     | 0.01     |
+-----------+--------+-----------+----------+-----------+----------+
| 1.6-2.7   | 35     | 750       | 33       | --107     | 0.01     |
+-----------+--------+-----------+----------+-----------+----------+
| 5.7-8.4   | 46     | 750       | 37       | --103     | 0.005    |
+-----------+--------+-----------+----------+-----------+----------+
| 10.7-11.5 | 50     | 1100      | 40       | --98      | 0.005    |
+-----------+--------+-----------+----------+-----------+----------+
| 12.5-14.8 | 52     | 1100      | 40       | --98      | 0.005    |
+-----------+--------+-----------+----------+-----------+----------+
| 17.7-19.7 | 48     | 1100      | 25 ^iv^  | --113     | 0.005    |
+-----------+--------+-----------+----------+-----------+----------+
| 24.7-29.5 | 50     | 2000      | 25 ^iv^  | --111     | 0.005    |
+-----------+--------+-----------+----------+-----------+----------+
| 40-51.4   | 42     | 2600      | 25 ^iv^  | --110     | 0.005    |
+-----------+--------+-----------+----------+-----------+----------+
| 47.2-50.2 | 46     | 2000      | 25 ^iv^  | --111     | 0.001    |
+-----------+--------+-----------+----------+-----------+----------+
| 71-95     | 45     | 2000      | 25 ^iv^  | --111     | 0.002    |
+-----------+--------+-----------+----------+-----------+----------+
| i         |        |           |          |           |          |
| .  System |        |           |          |           |          |
|     noise |        |           |          |           |          |
|     te    |        |           |          |           |          |
| mperature |        |           |          |           |          |
|           |        |           |          |           |          |
|   defined |        |           |          |           |          |
|     at    |        |           |          |           |          |
|     the   |        |           |          |           |          |
|     input |        |           |          |           |          |
|     to    |        |           |          |           |          |
|     the   |        |           |          |           |          |
|           |        |           |          |           |          |
|   antenna |        |           |          |           |          |
|           |        |           |          |           |          |
| terminal. |        |           |          |           |          |
|           |        |           |          |           |          |
| ii. These |        |           |          |           |          |
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|   control |        |           |          |           |          |
|           |        |           |          |           |          |
|   (ATPC). |        |           |          |           |          |
+-----------+--------+-----------+----------+-----------+----------+

TIA TSB 10-F defines default values for several key parameters that may
be used for frequency coordination purposes when more specific
information is not available; these parameters and their default values
are listed in Table 4-2.

**Table 4-2**

FS DMS Default Values in TIA TSB 10-F

  ---------------------------- ---------------------- -------------------
  Parameter                                           Default Value

  Per Hop Annual Path                                 99.999%
  Availability Objective                              

  Fade Margin at 10^-6^ BER    2 GHz band             35 dB

                               6 GHz band             40 dB

                               11 & 13 GHz bands      45 dB

                               18 GHz band            40 dB

  Receiver Noise Figure                               5 dB
  ---------------------------- ---------------------- -------------------

The performance of DMS is generally defined in terms of error
performance and availability objectives. The performance objectives
defined in the ITU-­R for the DMS systems implemented at the national
level are defined by a series of recommendations, with the most
important one from the standpoint of interference considerations being
Rec. ITU-R F.1189.[^10] In this Recommendation, each direction of a
multi-hop DMS system should meet the performance objectives listed in
Table 4-3.

Table 4-3

Error Performance Objectives of National FS DMS Systems

+-------------+---------+---------+----------+----------+------------+
| Bit Rate    | 1.5 to  | \>5 to  | \>15 to  | \>55 to  | \>160 to   |
| (Mb/s)      | 5       | 15      | 55       | 160      | 3500       |
+-------------+---------+---------+----------+----------+------------+
| Errored     | 0.04A   | 0.05A   | 0.075A   | 0.16A    | Under      |
| Second      |         |         |          |          | study      |
| Ratio (ESR) |         |         |          |          |            |
+-------------+---------+---------+----------+----------+------------+
| Severely    | 0.002A  | 0.002A  | 0.002A   | 0.002A   | 0.002A     |
| Errored     |         |         |          |          |            |
| Second      |         |         |          |          |            |
| Ratio       |         |         |          |          |            |
| (SESR)      |         |         |          |          |            |
+-------------+---------+---------+----------+----------+------------+
| Background  | 2A x    | 2A x    | 2A x     | 2A x     | A x 10^-4^ |
| Block Error | 10^-4^  | 10^-4^  | 10^-4^   | 10^-4^   |            |
| Ratio       |         |         |          |          |            |
| (BBER)      |         |         |          |          |            |
+-------------+---------+---------+----------+----------+------------+
| A = 0.015 + |         |         |          |          |            |
| 0.01L/500   |         |         |          |          |            |
| for long    |         |         |          |          |            |
| haul        |         |         |          |          |            |
| systems     |         |         |          |          |            |
|             |         |         |          |          |            |
| = 0.08 for  |         |         |          |          |            |
| short haul  |         |         |          |          |            |
| and local   |         |         |          |          |            |
| access      |         |         |          |          |            |
| systems     |         |         |          |          |            |
|             |         |         |          |          |            |
| L = total   |         |         |          |          |            |
| length of   |         |         |          |          |            |
| DMS         |         |         |          |          |            |
| network,    |         |         |          |          |            |
| rounded up  |         |         |          |          |            |
| to the next |         |         |          |          |            |
| multiple of |         |         |          |          |            |
| 500 km      |         |         |          |          |            |
|             |         |         |          |          |            |
| For         |         |         |          |          |            |
| definition  |         |         |          |          |            |
| of ESR,     |         |         |          |          |            |
| SESR, and   |         |         |          |          |            |
| BBER, see   |         |         |          |          |            |
| Rec. ITU-R  |         |         |          |          |            |
| F.1189.     |         |         |          |          |            |
+-------------+---------+---------+----------+----------+------------+

### Interference Protection Criteria

As described above, DMS are designed to achieve very low bit error
ratios with typical per hop availability of 99.999% or higher.
Equivalent outage times are measured in seconds per month. As a rule,
IPC values have been developed based on limiting degradation of
performance due to interfering signals to a designated percentage of the
overall degradation allowance. IPC values for DMS are generally defined
in ITU-R documentation in terms of I/N, whereas TIA TSB 10-F and FCC
Rules define the criteria in terms of C/I.[^11] For DMS, IPC values have
been discussed in three areas, namely, long-term interfering signal
levels, short-term interfering signal levels, and pulse interfering
signals; no information was identified regarding impulse forms of
interfering signals.

#### Long-Term Interfering Signals {#long-term-interfering-signals .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

Virtually all available studies addressing interference to DMS consider
low levels of CW, noise-like, and modulated interfering signals as all
having the same impact on system performance. For DMS, long-term
interfering signals refers to signal levels that are exceeded for 20% or
more of the time. One common misconception is that typical DMS design
features including high fade margins, forward error correction (FEC),
and ATPC circuitry impart a degree of immunity to interfering signals.
Both theory and practice show that this is not the case for continuous
long-term interfering signals. Both the large fade margins and FEC
circuitry (when employed) are key elements in achieving the high
reliability objectives; continuous interfering signals simply add to
system noise resulting in a reduction in link fade margin.

Regardless of the amount of fade margin or type of FEC designed into the
link, any reduction in fade margin due to interfering signals will lead
to a reduction in performance. As discussed later, large fade margins
and FEC may under certain conditions improve immunity to short-term and
pulse interfering signals, respectively. ATPC can actually increase the
vulnerability of a DMS receiver to short-term interfering signals. It
should be recognized that operationally measuring long-term performance
degradation due to interfering signals in FS systems is often difficult,
or impractical, because of the very long measurement time period
required.

Permissible levels of interference in FS receivers are commonly defined
differently depending on the source of the interference. A key ITU-R
document that defines performance degradation is Rec. ITU-R F.1094,
which describes three categories of interference sources to DMS,
namely,[^12]

-   sources within the FS,

-   other services sharing the same band on a primary basis, and

-   other emissions and radiations from sources having lesser rights
    then FS.

The latter includes sources such as secondary allocations, adjacent band
emissions, unlicensed systems, and industrial, scientific, and medical
(ISM) operations.

The different IPC levels for these three interference categories are
derived in that Recommendation by allocating 89%, 10%, and 1% of total
allowable degradation to interfering signals from these three
categories, respectively. These three categories of interference are
discussed below.

-   **Interference from Other FS Systems:**

In this category, I/N should not exceed --6 dB for more than 20% of any
month.

The methodology defined in Rec. ITU-R F.1094 allocates the largest
amount of performance loss, 89%, to factors within the FS, including
outage due to propagation fades, equipment breakdown, as well as
interfering signals, but provides no further allocation among these
factors. Therefore, this Recommendation does not provide specific
guidance for FS interferers.

TIA TSB 10-F is widely recognized domestically and is explicitly
accepted by both FCC and NTIA for FS sharing. The IPC specified in TSB
10-F are based on an increase in total noise of 1 dB or, equivalently, a
reduction in fade margin of 1 dB. In most FS bands, simultaneous
interfering signals from multiple FS transmitters is considered rare and
therefore, this criterion is commonly used as a single-entry
interference criterion. An exception is the non-government bands at 6
and 11 GHz where high equipment densities occur resulting in possible
multiple interfering signal exposures. A multiple exposure allowance
(MEA) for these two bands is defined in TIA TSB 10-F as follows:

> (I/N)~se~ = -- 6 -- MEA (dB) (4-1)

where (I/N)~se~ = single-entry long-term interference criteria,

> MEA = greater of {5, 10Log(BW~C~/BW~I~)},
>
> BW~C~ = receive bandwidth of victim carrier,
>
> BW~I~ = transmit bandwidth of interferer.

-   **Interference from Other Primary Allocated Services:**

In this category, I/N should not exceed --10 dB for more than 20% of any
month.

This level corresponds to a reduction in overall fade margin of about
0.4 dB. It can be shown that, under certain conditions, an I/N of --10
dB corresponds to the 10% performance degradation defined in Rec. ITU-R
F.1094 for sharing with other primary services.

-   **Interference from Non-Primary Allocated Services:**

In this category, I/N should not exceed --20 dB for more than 20% of any
month.

Rec. ITU-R F.1094 allocates 1% of the total performance degradation to
non-primary interfering signal sources. It can be shown that under
certain conditions this corresponds to an I/N ratio of --20 dB.

#### Short-Term Interfering Signals {#short-term-interfering-signals .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

The effects of short-term interfering signal levels have been shown to
differ depending on whether the DMS performance in the absence of
interfering signals is limited mainly by multipath fading or rain
fading. The former occurs in frequency bands below about 13 GHz and the
latter above about 17 GHz, with a transition zone between these
frequencies.

-   **Below 13 GHz**

The generally accepted procedure for assessing the effects of short-term
or time varying interfering signal levels on DMS performance in bands
below 13 GHz is found in Rec. ITU­R F.1108.[^13] This methodology, called
fractional degradation of performance (FDP), results in very simple
equations for non-diversity DMS links as follows:

$\text{FDP} = \text{10}^{\lbrack(\frac{I}{N})_{\text{ave}}(\text{dB})\frac{\rbrack}{\text{10}}}$
(4-2)

(I/N)~max~ 20 dB

where FDP = Fractional degradation of performance (corresponds to the
percentages defined in Rec. ITU-R F.1094),

(I/N)~ave~ = I/N from all sources, averaged over a sufficiently long
period of time to account for any periodicity in the interfering signal,

(I/N)~max~ = Maximum instantaneous value of I/N.

In this application, the average I/N does not refer to an average as may
result from pulsed type interfering signals, but rather to a CW or
noise-like interfering signals that are time varying or intermittent,
such as a mobile transmitter or low orbiting satellite. Evaluated in
this manner, the FDP methodology accounts for magnitudes of both
long-term and short-term interfering signals in any combination.

-   **Above 17 GHz**

Rec. ITU-R F.1495 describes IPC to protect the DMS from time varying
aggregate interfering signal from other primary services in the 18 GHz
band.[^14] These IPC include the following two constraints:

I/N NFM -- 5 (dB) not exceeded more than 0.01% of the time,

> NFM -- 1 (dB) not exceeded more than 0.0003% of the time,

where NFM is the net fade margin taking into account any use of ATPC.

No standardized methodology was identified for the transition region
between the above short percentages of time and long-term values.

#### Pulse Interfering Signals {#pulse-interfering-signals .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

The following discusses interference to DMS systems from pulse
interfering signals.

-   **DMS Not Employing Forward Error Correction**

As a rule, pulse interfering signal power should be evaluated in terms
of peak envelope power over the entire necessary bandwidth of a radio
channel of the interfered-with system.[^15] Pulse interfering signals in
DMS not employing FEC can often be just as damaging to performance, or
nearly so, as a continuous noise-like interferer. However, except for
the special case described below, few measurements or studies were
identified that address pulse interfering signals to DMS not employing
FEC. As default criteria, the criteria identified for noise-like
interfering signals may be used for pulse interfering signals, but using
the peak interfering signal power within the receiver passband.

Rec. ITU-R F.1190 identifies IPC for DMS operated below 7 GHz from fixed
and mobile radar systems. It did not take into account the possible use
of FEC. Based on the fact that radar antenna mainbeams either rotate or
continuously vary, the worst-case, peak interfering signal values only
occur intermittently. Consequently, short-term interference criteria may
be applied. For mobile radars, the fraction of time that the peak
interfering signal levels would occur is further reduced as a result of
the radar mobility. The following criteria were established:

Fixed or transportable radar interfering signals : I~pk~/N = 0 dB,

Maritime or land mobile radar interfering signals: I~pk~/N = 10 dB.

-   **DMS Employing Forward Error Correction**

Several studies have documented measurements demonstrating that under
certain conditions, a receiver employing FEC will be more immune to
pulse interfering signals than simple CW or noise-like interfering
signals. NTIA completed measurements on a digital satellite receiver
that would be similar in functionality to a DMS.[^16] For the single
case studied, the digital receiver was quite robust in the presence of
low duty cycle pulse interfering signals when the duty cycle is less
than 0.5%. The NTIA report gives guidance as to the degree of immunity
for various pulse widths and duty cycles but additional study would be
useful.

The NTIA study shows that for continuous pulse interfering signals
having a high duty cycle and/or long pulse characteristic, defined in
terms of peak power, resulted in the same degree of degradation as a CW
signal.

### Possible Mitigating Factors

The technical literature describes a number of situations where the
criteria discussed above may be relaxed as follows:

-   **Excess Link Margin**

While designers and operators of FS equipment, as is the case of all
radio services, aim to achieve the highest possible reliability, in
practice each link and the overall network as a whole are normally
designed to meet specified error performance and availability
objectives. From a practical standpoint, some links in the network may
be implemented with excess link margin, higher than necessary to achieve
these design objectives. For example:

-   A multi-hop microwave network may be designed around the single
    worst link in the network using common equipment (transmitters and
    antennas) for all links. The result is that all but one link in the
    network may have excess link margin.

-   FS transmitters are generally available in only one or two
    transmitter power options. The link designer must, in some cases,
    use the next higher power available, again resulting in possible
    excess link margin.

As described in TIA TSB 10-F, if excess fade margin is available, the
IPC may be relaxed dB for dB.[^17]

Using the C/I methodology and default values for fade margin described
in TIA TSB 10-F may also allow for relaxed IPC when excess fade margin
is present.[^18]

-   **Relaxed Degradation Criteria**

As described above, the baseline ITU-R degradation allowance for
co-primary sharing with DMS FS systems is 10%, or the equivalent I/N of
--10 dB. This criterion has been relaxed to 25%, or the equivalent I/N
of --6 dB, under certain situations to facilitate sharing, especially in
the 1-3 GHz region.

-   **Time Sharing**

Most FS systems are operated 100% of the time. Therefore time-sharing in
the conventional sense is generally not possible. However, microwave
fading due to multipath (i.e., in bands below about 13 GHz) generally
occurs during the period midnight to 8:00 am. If a potential interfering
system only operates during the 8:00 am to midnight time period, some
relaxation of the long-term IPC may be possible for DMS operations below
13 GHz.[^19]

-   **Short-haul Paths**

The established IPC for the DMS are generally based on long-haul
performance requirements with many links connected in tandem. However,
interfering signal levels 1-10 dB or more above these IPC values are
usually acceptable on shorter or other minimally fading digital paths
since long-term performance is not adversely affected.[^20]

## FIXED-SATELLITE SERVICE

### General

This subsection presents IPC for the FSS. The satellite can be in either
the geostationary orbit (GSO) or non-GSO (NGSO). Because of the
advantages of digital signal processing, most FSS traffic is digital, or
is expected to be digital after earth station receiver upgrades.
Therefore, only IPC of digital applications are presented.

A telecommunication satellite channel includes an uplink, the satellite,
and a downlink; noise is included in each portion. The signal quality,
in terms of error performance requirement, is discussed. The IPC are
specified as an apportionment of the total noise allowance, while the
total noise allowance is indirectly specified as the error performance
requirement.

### System Characteristics and Performance Objectives

#### System Characteristics {#system-characteristics .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

As in the case of the FS, FSS system characteristics vary over a wide
range and cannot be easily characterized. However, Appendix 7 of the
ITU-R Radio Regulations defines certain receiver technical parameters
for use in determination of coordination distances between receiving FSS
earth stations and FS systems. These values, summarized in Table 4-4,
may be useful in other spectrum sharing studies.

Table 4-4

FSS Default Values in Appendix 7 of ITU-R Radio Regulations

+------------+------+--------+-------+--------+------+-------+------+
| Band       | M    | M      | E     | Noise  | Fade | In    |      |
| (GHz)^i^   | ain- | inimal | qui-v | Tempe  | M    | terfe |      |
|            | beam | Elev   | alent | r-atur | ar-g | rence |      |
|            | An-t | a-tion | U     | e^iii^ | in,\ | Cr    |      |
|            | enna | Angle  | plink | (K)    | FM   | iteri |      |
|            | Gain | (Deg)  | N     |        | (dB) | a^iv^ |      |
|            | (    |        | oise, |        |      |       |      |
|            | dBi) |        | N~up~ |        |      |       |      |
|            |      |        | (dB   |        |      |       |      |
|            |      |        | )^ii^ |        |      |       |      |
+------------+------+--------+-------+--------+------+-------+------+
|            |      |        |       |        |      | I ^v^ | D    |
|            |      |        |       |        |      | (dBW  | ura- |
|            |      |        |       |        |      | /MHz) | tion |
|            |      |        |       |        |      |       | (%)  |
+------------+------+--------+-------+--------+------+-------+------+
| 2.5-2.69   | N/S  | 3      | 1     | 75     | 2    | --151 | 0    |
|            |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
| 3.4-4.2    | N/S  | 3      | 1     | 75     | 2    | --151 | 0    |
|            |      |        |       |        |      |       | .005 |
+------------+------+--------+-------+--------+------+-------+------+
| 4.5-4.8    | N/S  | 3      | 1     | 75     | 2    | --151 | 0    |
|            |      |        |       |        |      |       | .005 |
+------------+------+--------+-------+--------+------+-------+------+
| 5.15-5.216 | 48.5 | 3      | 1     | 75     | 2    | --151 | N/S  |
| N          |      |        |       |        |      |       |      |
+------------+------+--------+-------+--------+------+-------+------+
| 6.7-7.075  | 50.7 | 3      | 1     | 75     | 2    | --151 | 0    |
|            |      |        |       |        |      |       | .005 |
+------------+------+--------+-------+--------+------+-------+------+
| 7.25-7.75  | N/S  | N/S    | 1     | 75     | 2    | --151 | 0    |
|            |      |        |       |        |      |       | .005 |
+------------+------+--------+-------+--------+------+-------+------+
| 10.7-12.75 | N/S  | 5      | 1     | 150    | 4    | --144 | 0    |
|            |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
| 10.7-11.7  | 51.9 | 6      | 1     | 150    | 4    | --144 | 0    |
| N          |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
| 12.5-12.75 | 31.2 | 10     | 1     | 150    | 4    | --144 | 0    |
| N          |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
| 15.4-15.7  | 48.4 | 5      | 1     | 150    | 4    | --141 | 0    |
| N          |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
| 17.7-18.8  | 58.6 | 5      | 1     | 300    | 6    | --138 | 0    |
|            |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
| 18.8-19.3  | N/S  | N/S    | 0     | 300    | 5    | --141 | 0    |
|            |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
| 19.3-19.7  | 53.2 | 5      | 0     | 300    | 5    | --141 | 0.01 |
| N          |      |        |       |        |      |       |      |
+------------+------+--------+-------+--------+------+-------+------+
| 19.3-19.7  | 49.5 | 10     | 1     | 300    | 6    | --138 | 0    |
|            |      |        |       |        |      |       | .003 |
+------------+------+--------+-------+--------+------+-------+------+
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|     -- 1)  |      |        |       |        |      |       |      |
|     .      |      |        |       |        |      |       |      |
+------------+------+--------+-------+--------+------+-------+------+

#### Performance Objectives {#performance-objectives .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

In satellite communications, interference regulation is typically an
international issue. Thus, FSS frequency coordination procedures,
sharing criteria, and IPC have been established by the ITU-R in its "S
series" of Recommendations. A satellite operator, an administration, or
an entire ITU-R Region may impose more stringent IPC to meet their
interference suppression or frequency reuse requirements.

The signal quality of a digital channel is the bit error ratio (BER)
after decoding. Different coding schemes yield different BER for the
same C/N at the input of the demodulator. Since coding schemes are
implemented by system designers, and can vary even during operation, the
total noise allowance can be specified only indirectly by the BER
requirement. Therefore, in ITU-R Recommendations, the digital channel
performance requirement is specified in terms of an array of BER and
availabilities. Each transmission link has its own C/N requirement that
will enable compliance with the required BER. The IPC are determined by
budgeting total system noise allowance to the interfering signal power,
where the total system noise is defined as the noise level giving rise
to certain BER under clear sky conditions. A summary of these
Recommendations are listed in Table 4-5 for various digital channels.

**Table 4-5**

List of ITU-R Recommendations Related to IPC

+-------------------------------+-------------------+-------------------+
|                               | ITU-R             |                   |
|                               | Recommendations   |                   |
+-------------------------------+-------------------+-------------------+
| Signal                        | Error Performance | Interfering       |
|                               | Objective         | Signal Power      |
|                               |                   | Apportionment     |
+-------------------------------+-------------------+-------------------+
| Digital connection as part of | S.1062 [^21]^,^   | S.1323 [^22]      |
| international network at or   | ^i^               |                   |
| above T1 rate                 |                   | S.1429 [^23]^,^   |
|                               |                   | ^ii^              |
+-------------------------------+-------------------+-------------------+
| Digital connection as part of | S.614 [^24]       | S.735 [^25]       |
| international Integrated      |                   |                   |
| Service Digital Network       |                   |                   |
| (ISDN)                        |                   |                   |
+-------------------------------+-------------------+-------------------+
| Digital Pulse Code Modulation | S.522 [^26]       | S.523 [^27]       |
| (PCM) telephony, non-ISDN     |                   |                   |
+-------------------------------+-------------------+-------------------+
| Digital Single Channel per    | N/S               | S.671 [^28]       |
| Carrier (SCPC) interfered     |                   |                   |
| with by TV/FM                 |                   |                   |
+-------------------------------+-------------------+-------------------+
| i.  Performance objectives    |                   |                   |
|     specific to Asynchronous  |                   |                   |
|     Transfer Mode (ATM)       |                   |                   |
|     transmission are in       |                   |                   |
|     S.1420.[^29]              |                   |                   |
|                               |                   |                   |
| ii. For short-term            |                   |                   |
|     interfering signals       |                   |                   |
|     occurring between GSO/FSS |                   |                   |
|     and NGSO/FSS systems.     |                   |                   |
+-------------------------------+-------------------+-------------------+

### Error Performance Objective

#### Long-term Interfering Signals  {#long-term-interfering-signals-1 .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

FSS digital signal transmission is generally classified as broadband or
narrowband. Broadband transmission is defined as data rate of 1.5 Mb/s
or above (1.5 Mb/s is called T1 rate in the U.S. and primary rate in
ITU-R documents.) Narrowband transmission can be either ISDN at data
rate of 64 kb/s, or multiples thereof.

The end-to-end error performance objective of a broadband international
connection and the error performance apportionment to a satellite
hypothetical reference digital path (HRDP) are given in Rec. ITU
Telecommunications Sector (ITU-T) G.826.[^30] Based on the G.826
requirements, Rec. ITU-R S.1062 specifies the allowable error
performance of a FSS satellite HRDP as follows: the allowable BER at the
output of a HRDP should not exceed the mask given in Table 4-6.

**Table 4-6**

FSS Error Performance Objectives

+--------------------+----------------------+--------------------------+
| Bit Rate (Mb/s)    | \% Total Time, Worst | BER/α ^i^                |
|                    | Month                |                          |
+--------------------+----------------------+--------------------------+
| 1.5                | 0.2                  | 7x10^-7^                 |
+--------------------+----------------------+--------------------------+
|                    | 2                    | 3x10^-8^                 |
+--------------------+----------------------+--------------------------+
|                    | 10                   | 5x10^-9^                 |
+--------------------+----------------------+--------------------------+
| 2                  | 0.2                  | 7x10^-6^                 |
+--------------------+----------------------+--------------------------+
|                    | 2                    | 2x10^-8^                 |
+--------------------+----------------------+--------------------------+
|                    | 10                   | 2x10^-9^                 |
+--------------------+----------------------+--------------------------+
| 6                  | 0.2                  | 8x10^-7^                 |
+--------------------+----------------------+--------------------------+
|                    | 2                    | 1x10^-8^                 |
+--------------------+----------------------+--------------------------+
|                    | 10                   | 1x10^-9^                 |
+--------------------+----------------------+--------------------------+
| 51                 | 0.2                  | 4x10^-7^                 |
+--------------------+----------------------+--------------------------+
|                    | 2                    | 2x10^-9^                 |
+--------------------+----------------------+--------------------------+
|                    | 10                   | 2x10^-10^                |
+--------------------+----------------------+--------------------------+
| 155                | 0.2                  | 1x10^-7^                 |
+--------------------+----------------------+--------------------------+
|                    | 2                    | 1x10^-9^                 |
+--------------------+----------------------+--------------------------+
|                    | 10                   | 1x10^-10^                |
+--------------------+----------------------+--------------------------+
| i.  α: average     |                      |                          |
|     number of      |                      |                          |
|     errored bits   |                      |                          |
|     in a burst of  |                      |                          |
|     errors.\       |                      |                          |
|     The            |                      |                          |
|     specification  |                      |                          |
|     applies to     |                      |                          |
|     systems        |                      |                          |
|     operating      |                      |                          |
|     below 30 GHz.  |                      |                          |
|                    |                      |                          |
| > Rec. ITU-T G.826 |                      |                          |
| > uses             |                      |                          |
| > bit              |                      |                          |
| -error-probability |                      |                          |
| > (BEP) instead of |                      |                          |
| > BER.             |                      |                          |
+--------------------+----------------------+--------------------------+

The end-to-end error performance objective of a 64 kb/s ISDN
international connection and the error performance apportionment to a
satellite HRDP are given in Rec. ITU-T G.821.[^31] Based on the G.821
requirements, Rec. ITU-R S.614 specifies the error performance of a 64
kb/s satellite HRDP as follows: the BER at the output of a satellite
HRDP operating below 15 GHz should not exceed:

-   10^-7^ for more than 10% of any month,

-   10^-6^ for more than 2% of any month,

-   10^-3^ for more than 0.03% of any month.

The performance requirement for PCM telephony is given in Rec. ITU-R
S.522 as follows: the allowable BER at the output of the HRDP should not
exceed:

-   10^-6^, 10-minute mean value for more than 20% of any month,

-   10^-4^, 1-minute mean value for more than 0.3% of any month,

-   10^-3^, 1-second mean value for more than 0.05% of any month.

#### Short-term Interfering Signals {#short-term-interfering-signals-1 .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

Rec. ITU-R S.1323 specifies that interfering signals between FSS
networks (GSO/FSS, NGSO/FSS, NGSO/MSS feeder link) which are considered
short-term and time-variant should:

-   be responsible for at most 10% of the time allowance for the BER (or
    C/N) specified in the short-term performance objectives and
    corresponding to the shortest percentage of time (or lowest C/N
    value),

-   not lead to loss of synchronization for more than once per x days,
    with the value of x for further study.

Since ITU-R documents consider the interfering signals between GSO/FSS
and NGSO/FSS systems to be short-term, it is specified in Rec. ITU-R
S.1429 that 10% of the error performance objective should be allotted to
the short-term interfering signals between GSO/FSS and NGSO/FSS systems.
Specifically, the allotment is listed in Table 4-7.

**Table 4-7**

FSS Error Performance Objectives

for Short-term Interfering Signals

  ------------------- ---------------------------- ----------------------
  Bit Rate (Mb/s)     \% Total Time, Worst Month   BER/α

  1.5                 0.02                         7x10^-7^

                      0.2                          3x10^-8^

                      1                            5x10^-9^

  2                   0.02                         7x10^-6^

                      0.2                          2x10^-8^

                      1                            2x10^-9^

  6                   0.02                         8x10^-7^

                      0.2                          1x10^-8^

                      1                            1x10^-9^

  51                  0.02                         4x10^-7^

                      0.2                          2x10^-9^

                      1                            2x10^-10^

  155                 0.02                         1x10^-7^

                      0.2                          1x10^-9^

                      1                            1x10^-10^

  Applicable to                                    
  transmissions below                              
  15 GHz.                                          
  ------------------- ---------------------------- ----------------------

### Interference Protection Criteria Summary

ITU-R documents describe a unified interfering signal noise
apportionment for all digital FSS channels. Rec. ITU-R S.1432 summarizes
the IPC from Recs. ITU-R S.523, S.671, S.735 and S.1323 as follows:[^32]

For FSS systems operating below 15 GHz, the apportionment of the
allowable aggregate interfering signal is limited to:

-   32% of the clear sky satellite system noise for systems not
    practicing frequency reuse;

-   27% of the clear sky satellite system noise for systems practicing
    frequency reuse.

The aggregate interfering signal is further partitioned as follows:

-   25% for other FSS systems for victim system not practicing frequency
    reuse;

-   20% for other FSS systems for victim system practicing frequency
    reuse;

-   6% for other systems having co-primary status;

-   1% for all other sources.

Frequency reuse is a technique to utilize either electromagnetic wave
polarization isolation or antenna direction isolation (sometimes called
coverage area spatial isolation) characteristics to reuse the same
frequency band multiple times on the same satellite network. Almost all
FSS systems use polarization isolation to use the frequency band twice,
and some use direction isolation to further reuse the frequency band
multiple times. For example, most of the INTELSAT satellites utilize
both isolation characteristics to use the same frequency band 6 times.
Frequency reuse generates additional intra-system noise.

Recs. ITU-R S.523, S.671, S.735 and S.1323 specify that the single-entry
interfering signal power apportionment is 6%.

Rec. ITU-R S.1323 also specifies that short-term interfering signals
between the FSS systems should account for only 10% of the error
performance allotment. Rec. ITU-R S.1429 provides more specific
information.

#### Coordination Trigger {#coordination-trigger .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

For a proposed FSS system sharing the same frequency bands with existing
or other proposed FSS systems, there is a need to determine if
coordination is required to prevent unacceptable mutual interference.
The ITU-R provides two methodologies to calculate trigger levels for
determining if coordination action is required.

From Rec. ITU-R S.738, the trigger level to determine if coordination
action is required between two GSO/FSS systems is:[^33]

> ΔT/T ≥ 6%, (4-3)

Where: ΔT = Increase in system noise temperature due to interfering
signals,

T = receiver noise temperature,

k(ΔT)B = I,

kTB = N ,

k = Boltzmann's constant,

B = carrier bandwidth.

From Rec. ITU-R S.739, a less conservative trigger level to determine if
coordination action is required between two GSO/FSS systems is the
normalized ΔT/T value, which modifies the ΔT/T value by taking into
account the interfered-with and the interfering carriers.[^34]

#### IPC for Fixed Satellite Service Broadband Digital Signals {#ipc-for-fixed-satellite-service-broadband-digital-signals .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

The IPC for broadband digital signal transmission are given in Rec.
ITU-R S.1323. The maximum permissible level of interference between
GSO/FSS satellite networks is considered time-invariant and should not
exceed, under clear-sky conditions,

-   for aggregate interfering signal power:

-   25% of total system noise power level for systems not practicing
    frequency reuse;

-   20% of total system noise power level for systems practicing
    frequency reuse;

-   for single-entry interfering signal power: 6% of total system noise
    power level.

Here the total system noise power level is defined as the noise power at
the input of the demodulator, which gives rise to BER of 10^-6^. The
criteria apply to transmissions below 30 GHz.

#### IPC for Fixed Satellite Service Narrowband Digital Signals {#ipc-for-fixed-satellite-service-narrowband-digital-signals .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

The IPC for ISDN transmission are given in Rec. ITU-R S.735. The maximum
permissible level of interference from other FSS systems to a 64 kb/s
GSO/FSS satellite ISDN link should not exceed, under clear-sky
conditions,

-   for aggregate interfering signal power:

```{=html}
<!-- -->
```
-   25% of total noise power level for systems not practicing frequency
    reuse;

-   20% of total noise power level for systems practicing frequency
    reuse;

```{=html}
<!-- -->
```
-   for single-entry interfering signal power: 6% of total noise power
    level.

Here the total noise power level is defined as the noise power at the
input of the demodulator which gives rise to BER of 10^-6^. The criteria
apply to systems operating below 15 GHz.

## SUMMARY 

Tables 4-7 and 4-8 present summaries of IPC for the FS and FSS.

+-------+------+----------+---------+------+------+--------+--------+
| Sys   | F    | Inte     |         | R    | \%   | Source | Co     |
| tems/ | requ | rference |         | efer | Time | Docum  | mments |
| Ser   | ency | Pr       |         | ence |      | ent(s) |        |
| vices | B    | otection |         | B    |      |        |        |
|       | ands | Criteria |         | andw |      |        |        |
|       |      |          |         | idth |      |        |        |
+=======+======+==========+=========+======+======+========+========+
|       |      | CW/Noise | Puls    |      |      |        |        |
|       |      |          | e/Other |      |      |        |        |
+-------+------+----------+---------+------+------+--------+--------+
| FS    | All  | I/N ≤    | see     | 1    | 20   | TIA    | Lon    |
| (DMS) | FS   | --6 dB   | rows    | MHz  | (of  | TSB    | g-term |
|       | b    | (Other   | below   |      | any  | 10-F,  | inter  |
|       | ands | FS       |         |      | mo   |        | fering |
|       |      | systems) |         |      | nth) | ITU-R  | S      |
|       |      |          |         |      |      | F      | ignals |
|       |      |          |         |      |      | .1094, |        |
|       |      |          |         |      |      |        |        |
|       |      |          |         |      |      | NTIA   |        |
|       |      |          |         |      |      | Report |        |
|       |      |          |         |      |      | 02-393 |        |
+-------+------+----------+---------+------+------+--------+--------+
|       |      | I/N ≤    |         |      |      |        |        |
|       |      | --10 dB  |         |      |      |        |        |
|       |      | (Other   |         |      |      |        |        |
|       |      | primary  |         |      |      |        |        |
|       |      | s        |         |      |      |        |        |
|       |      | ervices) |         |      |      |        |        |
+-------+------+----------+---------+------+------+--------+--------+
|       |      | I/N ≤    |         |      |      |        |        |
|       |      | --20 dB  |         |      |      |        |        |
|       |      | (Non     |         |      |      |        |        |
|       |      | -primary |         |      |      |        |        |
|       |      | sources) |         |      |      |        |        |
+-------+------+----------+---------+------+------+--------+--------+
|       | All  | (        | see     | 1    | Any  | Rec.   | Shor   |
|       | FS   | I/N)~av~ | rows    | MHz  |      | ITU-R  | t-term |
|       | b    | ≤ --10   | below   |      |      | F.1108 | Mul    |
|       | ands | dB       |         |      |      |        | tipath |
|       | b    | (Other   |         |      |      |        | fading |
|       | elow | Primary  |         |      |      |        | domin  |
|       | 13   | S        |         |      |      |        | ates;\ |
|       | GHz  | ervices) |         |      |      |        | (I/N   |
|       |      |          |         |      |      |        | )~max~ |
|       |      |          |         |      |      |        | not to |
|       |      |          |         |      |      |        | exceed |
|       |      |          |         |      |      |        | 20 dB  |
+-------+------+----------+---------+------+------+--------+--------+
|       |      | (I/N)    |         |      |      |        |        |
|       |      | ~av~ ≤   |         |      |      |        |        |
|       |      | --20 dB  |         |      |      |        |        |
|       |      | (Non     |         |      |      |        |        |
|       |      | -primary |         |      |      |        |        |
|       |      | sources) |         |      |      |        |        |
+-------+------+----------+---------+------+------+--------+--------+
|       | All  | I/N ≤    | see     | 1    | 0.01 | Rec.   | Shor   |
|       | FS   | NFM^i^   | rows    | MHz  |      | ITU-R  | t-term |
|       | b    | -- 5 dB  | below   |      |      | F.1495 | Rain   |
|       | ands |          |         |      |      |        | fading |
|       | a    |          |         |      |      |        | dom    |
|       | bove |          |         |      |      |        | inates |
|       | 17   |          |         |      |      |        |        |
|       | GHz  |          |         |      |      |        |        |
+-------+------+----------+---------+------+------+--------+--------+
|       |      | I/N ≤    |         |      | 0    |        |        |
|       |      | NFM -- 1 |         |      | .003 |        |        |
|       |      | dB       |         |      |      |        |        |
+-------+------+----------+---------+------+------+--------+--------+

+-------+------+----------+---------+-------+-----+---------+--------+
| Sys   | F    | Inte     |         | Refe  | \%  | Source  | Co     |
| tems/ | requ | rference |         | rence | T   | Docu    | mments |
| Ser   | ency | Pr       |         | Band  | ime | ment(s) |        |
| vices | B    | otection |         | width |     |         |        |
|       | ands | Criteria |         |       |     |         |        |
+-------+------+----------+---------+-------+-----+---------+--------+
|       |      | CW/Noise | Puls    |       |     |         |        |
|       |      |          | e/Other |       |     |         |        |
+-------+------+----------+---------+-------+-----+---------+--------+
| FS    | All  | see rows | Same    | IF    | N/S | Rec.    | Cont   |
| (DMS  | FS   | above    | c       | Pas   |     | ITU-R   | inuous |
| wi    | b    |          | riteria | sband |     | F.1190  | pulse  |
| thout | ands |          | as      |       |     |         | inter  |
| FEC)  |      |          | noise   |       |     |         | fering |
|       |      |          | using   |       |     |         | signal |
|       |      |          | peak    |       |     |         |        |
|       |      |          | inte    |       |     |         |        |
|       |      |          | rfering |       |     |         |        |
|       |      |          | signal  |       |     |         |        |
|       |      |          | power   |       |     |         |        |
+-------+------+----------+---------+-------+-----+---------+--------+
|       | B    | see rows | I/N ≤ 0 | IF    | N/S | Rec.    | Radars |
|       | elow | above    | dB      | Pas   |     | ITU-R   | with   |
|       | 6    |          |         | sband |     | F.1190  | ro     |
|       | GHz  |          | (Fixed  |       |     |         | tating |
|       |      |          | radar   |       |     |         | an     |
|       |      |          | source) |       |     |         | tennas |
+-------+------+----------+---------+-------+-----+---------+--------+
|       |      |          | I/N ≤   |       |     |         |        |
|       |      |          | 10 dB   |       |     |         |        |
|       |      |          | (Mobile |       |     |         |        |
|       |      |          | radar   |       |     |         |        |
|       |      |          | source) |       |     |         |        |
+-------+------+----------+---------+-------+-----+---------+--------+
| FS    | All  | see rows | See     | IF    | Lon | NTIA    | Cont   |
| (DMS  | FS   | above    | text    | Pas   | g-t | Report  | inuous |
| with  | b    |          |         | sband | erm | 02-393  | or     |
| FEC)  | ands |          |         |       |     |         | pulse  |
|       |      |          |         |       |     |         | inter  |
|       |      |          |         |       |     |         | fering |
|       |      |          |         |       |     |         | s      |
|       |      |          |         |       |     |         | ignals |
+-------+------+----------+---------+-------+-----+---------+--------+
| i.    |      |          |         |       |     |         |        |
|   NFM |      |          |         |       |     |         |        |
|     = |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|   Net |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|  fade |      |          |         |       |     |         |        |
|     m |      |          |         |       |     |         |        |
| argin |      |          |         |       |     |         |        |
|     t |      |          |         |       |     |         |        |
| aking |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|  into |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|    ac |      |          |         |       |     |         |        |
| count |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|   the |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|   use |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|    of |      |          |         |       |     |         |        |
|       |      |          |         |       |     |         |        |
|  ATPC |      |          |         |       |     |         |        |
+-------+------+----------+---------+-------+-----+---------+--------+

+------+------+------------+-------+------+------+--------+----------+
| Syst | F    | In         |       | R    | \%   | Source | Comments |
| ems/ | requ | terference |       | efer | Time | Docum  |          |
|      | ency | Protection |       | ence |      | ent(s) |          |
| Serv | B    | Criteria   |       | B    |      |        |          |
| ices | ands |            |       | andw |      |        |          |
|      |      |            |       | idth |      |        |          |
+------+------+------------+-------+------+------+--------+----------+
|      |      | CW/Noise   | P     |      |      |        |          |
|      |      |            | ulse/ |      |      |        |          |
|      |      |            | Other |      |      |        |          |
+------+------+------------+-------+------+------+--------+----------+
| FSS  | All  | I~tot      | N/S   | IF   | 20   | ITU-R  | For FSS  |
|      | FSS  | al~/N~BER~ |       | Pass | (of  | S.523  | system   |
|      | b    | ≤ --5.7 dB |       | band | any  | ITU-R  | pr       |
|      | ands |            |       |      | mo   | S.671\ | acticing |
|      | b    | I~agg,\ F  |       |      | nth) | ITU-R  | f        |
|      | elow | SS~/N~BER~ |       |      |      | S.735\ | requency |
|      | 15   | ≤ --7 dB   |       |      |      | ITU-R  | reuse.   |
|      | GHz  |            |       |      |      | S.1323 |          |
|      |      | I~se,\ F   |       |      |      | ITU-R  |          |
|      |      | SS~/N~BER~ |       |      |      | S.1432 |          |
|      |      | ≤ --12 dB  |       |      |      |        |          |
|      |      |            |       |      |      |        |          |
|      |      | I~co-pr    |       |      |      |        |          |
|      |      | im~/N~BER~ |       |      |      |        |          |
|      |      | ≤ --12 dB  |       |      |      |        |          |
|      |      |            |       |      |      |        |          |
|      |      | I~othe     |       |      |      |        |          |
|      |      | rs~/N~BER~ |       |      |      |        |          |
|      |      | ≤ --20 dB  |       |      |      |        |          |
+------+------+------------+-------+------+------+--------+----------+
|      | All  | 10% of     | N/S   | IF   | Sh   | ITU-R  | A        |
|      | FSS  | error      |       | Pass | ort- | S.1429 | ggregate |
|      | b    | p          |       | band | term |        | int      |
|      | ands | erformance |       |      |      |        | erfering |
|      |      | objective  |       |      |      |        | signals  |
|      |      |            |       |      |      |        | between  |
|      |      |            |       |      |      |        | GSO/FSS  |
|      |      |            |       |      |      |        | and      |
|      |      |            |       |      |      |        | NGSO/FSS |
+------+------+------------+-------+------+------+--------+----------+
| F    |      |            |       |      |      |        |          |
| requ |      |            |       |      |      |        |          |
| ency |      |            |       |      |      |        |          |
| re   |      |            |       |      |      |        |          |
| use: |      |            |       |      |      |        |          |
| a    |      |            |       |      |      |        |          |
| s    |      |            |       |      |      |        |          |
| atel |      |            |       |      |      |        |          |
| lite |      |            |       |      |      |        |          |
| re   |      |            |       |      |      |        |          |
| uses |      |            |       |      |      |        |          |
| the  |      |            |       |      |      |        |          |
| same |      |            |       |      |      |        |          |
| f    |      |            |       |      |      |        |          |
| requ |      |            |       |      |      |        |          |
| ency |      |            |       |      |      |        |          |
| band |      |            |       |      |      |        |          |
| mult |      |            |       |      |      |        |          |
| iple |      |            |       |      |      |        |          |
| ti   |      |            |       |      |      |        |          |
| mes, |      |            |       |      |      |        |          |
|      |      |            |       |      |      |        |          |
| I~to |      |            |       |      |      |        |          |
| tal~ |      |            |       |      |      |        |          |
| t    |      |            |       |      |      |        |          |
| otal |      |            |       |      |      |        |          |
| int  |      |            |       |      |      |        |          |
| erfe |      |            |       |      |      |        |          |
| ring |      |            |       |      |      |        |          |
| si   |      |            |       |      |      |        |          |
| gnal |      |            |       |      |      |        |          |
| po   |      |            |       |      |      |        |          |
| wer, |      |            |       |      |      |        |          |
|      |      |            |       |      |      |        |          |
| I~ag |      |            |       |      |      |        |          |
| g,\  |      |            |       |      |      |        |          |
| FSS~ |      |            |       |      |      |        |          |
| t    |      |            |       |      |      |        |          |
| otal |      |            |       |      |      |        |          |
| int  |      |            |       |      |      |        |          |
| erfe |      |            |       |      |      |        |          |
| ring |      |            |       |      |      |        |          |
| si   |      |            |       |      |      |        |          |
| gnal |      |            |       |      |      |        |          |
| p    |      |            |       |      |      |        |          |
| ower |      |            |       |      |      |        |          |
| from |      |            |       |      |      |        |          |
| o    |      |            |       |      |      |        |          |
| ther |      |            |       |      |      |        |          |
| FSS  |      |            |       |      |      |        |          |
| s    |      |            |       |      |      |        |          |
| yste |      |            |       |      |      |        |          |
| ms,\ |      |            |       |      |      |        |          |
| I~s  |      |            |       |      |      |        |          |
| e,\  |      |            |       |      |      |        |          |
| FSS~ |      |            |       |      |      |        |          |
| int  |      |            |       |      |      |        |          |
| erfe |      |            |       |      |      |        |          |
| ring |      |            |       |      |      |        |          |
| si   |      |            |       |      |      |        |          |
| gnal |      |            |       |      |      |        |          |
| p    |      |            |       |      |      |        |          |
| ower |      |            |       |      |      |        |          |
| from |      |            |       |      |      |        |          |
| ano  |      |            |       |      |      |        |          |
| ther |      |            |       |      |      |        |          |
| FSS  |      |            |       |      |      |        |          |
| syst |      |            |       |      |      |        |          |
| em,\ |      |            |       |      |      |        |          |
| I~   |      |            |       |      |      |        |          |
| co-p |      |            |       |      |      |        |          |
| rim~ |      |            |       |      |      |        |          |
| t    |      |            |       |      |      |        |          |
| otal |      |            |       |      |      |        |          |
| int  |      |            |       |      |      |        |          |
| erfe |      |            |       |      |      |        |          |
| ring |      |            |       |      |      |        |          |
| si   |      |            |       |      |      |        |          |
| gnal |      |            |       |      |      |        |          |
| p    |      |            |       |      |      |        |          |
| ower |      |            |       |      |      |        |          |
| from |      |            |       |      |      |        |          |
| serv |      |            |       |      |      |        |          |
| ices |      |            |       |      |      |        |          |
| of   |      |            |       |      |      |        |          |
| co   |      |            |       |      |      |        |          |
| -pri |      |            |       |      |      |        |          |
| mary |      |            |       |      |      |        |          |
| stat |      |            |       |      |      |        |          |
| us,\ |      |            |       |      |      |        |          |
| I    |      |            |       |      |      |        |          |
| ~oth |      |            |       |      |      |        |          |
| ers~ |      |            |       |      |      |        |          |
| t    |      |            |       |      |      |        |          |
| otal |      |            |       |      |      |        |          |
| int  |      |            |       |      |      |        |          |
| erfe |      |            |       |      |      |        |          |
| ring |      |            |       |      |      |        |          |
| si   |      |            |       |      |      |        |          |
| gnal |      |            |       |      |      |        |          |
| p    |      |            |       |      |      |        |          |
| ower |      |            |       |      |      |        |          |
| from |      |            |       |      |      |        |          |
| all  |      |            |       |      |      |        |          |
| o    |      |            |       |      |      |        |          |
| ther |      |            |       |      |      |        |          |
| sour |      |            |       |      |      |        |          |
| ces, |      |            |       |      |      |        |          |
|      |      |            |       |      |      |        |          |
| N~   |      |            |       |      |      |        |          |
| BER~ |      |            |       |      |      |        |          |
| t    |      |            |       |      |      |        |          |
| otal |      |            |       |      |      |        |          |
| c    |      |            |       |      |      |        |          |
| lear |      |            |       |      |      |        |          |
| sky  |      |            |       |      |      |        |          |
| n    |      |            |       |      |      |        |          |
| oise |      |            |       |      |      |        |          |
| p    |      |            |       |      |      |        |          |
| ower |      |            |       |      |      |        |          |
| gi   |      |            |       |      |      |        |          |
| ving |      |            |       |      |      |        |          |
| rise |      |            |       |      |      |        |          |
| to   |      |            |       |      |      |        |          |
| the  |      |            |       |      |      |        |          |
| BER  |      |            |       |      |      |        |          |
| ob   |      |            |       |      |      |        |          |
| ject |      |            |       |      |      |        |          |
| ive. |      |            |       |      |      |        |          |
+------+------+------------+-------+------+------+--------+----------+

REFERENCES

#  RADIODETERMINATION AND RADIODETERMINATION-SATELLITE SERVICES

## Introduction

Various types of systems operate in the radiodetermination and
radiodetermination-satellite services from 30 MHz to 30 GHz. These
systems perform a variety of functions in the United States, including
monitoring weather phenomena, surveillance of the national airspace and
waterways, and providing navigation safety-of-life services.

The radiodetermination service includes radiolocation, aeronautical
radionavigation and maritime radionavigation services. With the
exception of aeronautical and maritime radionavigation systems that use
transponders or transmit information to and from ground stations, these
systems rely on passively reflected or scattered radar signal returns to
detect and/or track point targets (e.g., planes, ships,). Meteorological
aids (weather radars) are also included here because of certain
commonalties they have with radars that are operated in the
radiodetermination service (i.e., pulse width, pulse rate, and type of
transmitter output device). However, weather radars are designed to
detect/monitor distributed targets such as clouds, rain, hail, and other
weather phenomena. Radar altimeters are unique in that they radiate
towards the earth so that aircraft can determine their height above
ground.

The form of the IPC for radiodetermination systems that rely on
reflected returns is I/N. For aeronautical radionavigation systems that
employ a data-link between ground stations and aircraft, the IPC are in
the form of S/I, an absolute interfering signal power limit, or other
form.

## Radiodetermination Service

### Radars operated in the Radiolocation, Aeronautical Radionavigation, Meteorological Aids, and Maritime Radionavigation Services

The technical characteristics and IPC for systems operating in the
radiolocation and radionavigation services are contained in Part 4 of
the M series of the ITU-R Recommendations. Rec. ITU-R. M.1461 contains
the general IPC for these systems if no other IPC are identified in a
Recommendation that addresses a particular frequency band.[^35] Rec.
ITU-R M.1461 also contains guidance on the methodology for analysis of
potential interfering signals between radars and systems operating in
other services. Table 5-1 lists the relevant ITU-R Recommendations that
are in effect and the preliminary and draft new Recommendations (DNR).

Table 5-1

List of Relevant ITU-R Recommendations

for Radiodetermination Service

  -------------------------- ------------------- ------------------------
  Frequency Band And Service IPC for CW and      ITU-R Recommendation
                             Noise-like          
                             Interfering Signals 

  420-450 MHz Radiolocation  I/N ≤ --6 dB        M. 1462[^36]

  1215-1400 MHz              I/N ≤ --6 dB        M. 1463[^37]
  Radiodetermination                             

  2700-2900 MHz              I/N ≤ --10 dB       M. 1464[^38]
  Radionavigation and                            
  Meteorological Aids                            

  2900-3100 MHz Maritime     I/N ≤ --6 dB        M. 1313[^39]
  Radionavigation                                

  2900-3100 MHz              I/N ≤ --6 dB        M. 1460[^40]
  Radiodetermination and                         
  Meteorological Aids                            

  3100-3700 MHz              I/N ≤ --6 dB        M. 1465[^41]
  Radiodetermination                             

  5250-5850 MHz              I/N ≤ --6 dB        M. 1638[^42]
  Radiolocation,                                 
  Aeronautical                                   
  Radionavigation, and                           
  Meteorological Aids                            

  8500-10500 MHz             I/N ≤ --6 dB        Preliminary DNR\
  Radiodetermination                             (Doc.# 8B/282)

  13.75-14 GHz Radiolocation I/N ≤ --6dB         M. 1644[^43]
  and Radionavigation                            

  31.8-33.4 GHz              I/N ≤ --6 dB        M. 1466[^44]
  Radionavigation                                

  33.4-36 GHz                I/N ≤ --6 dB        M. 1640[^45]
  Radiodetermination                             

  All except as noted        I/N ≤ --6 dB        M. 1461
  -------------------------- ------------------- ------------------------

### CW and Noise-like Interfering Signals

The baseline ITU-R IPC for interfering signals that appear CW or
noise-like in the radar receiver are an I/N of --6 dB for single entry
and aggregate interfering signals if multiple interferers are present.
The I/N is calculated within the 3 dB IF bandwidth of the victim
receiver. The IPC represents a 1 dB increase in the effective noise
power of the radar receiver. These IPC do not apply to interfering
signals that appear pulse-like in the radar receiver. The I/N of -6 dB
applies 100% of the time, and so, it is applied for both long-term and
short-term interfering signals. In the ITU, Work Party 8B has developed
a work program to address the feasibility of determining IPC based on
statistical methods.

The IPC in the ITU-R Recommendations are not referenced to particular
radar performance standards such as a decrease in the target probability
of detection or an increase in the number of false targets. However, the
performance degradation can be determined once the specific system
characteristics are known along with the IPC. For maritime radars, the
International Maritime Organization (IMO) specifies that radars
operating on a vessel must be able to detect a target of 10 square
meters at a distance of 2 nautical miles.[^46] A European standard
exists for the performance of aeronautical surveillance radars that
specifies the minimum probability of target detection is 0.90.[^47]

NTIA, with assistance from the Federal Aviation Administration (FAA),
National Weather Service (NWS) and the United States Coast Guard (USCG),
performed tests with maritime radars in the 2900-3100 MHz band and with
aeronautical radionavigation radars and meteorological aids in the
2700-2900 MHz band to determine if the current ITU-R I/N IPC are
stringent enough to protect their operations. The results of these tests
were submitted to the ITU as contributions to Working Party 8B (WP8B) as
United States contributions (WP8B Documents 8B/275 and 8B/272 (available
from NTIA)). Eurocontrol also submitted a similar contribution to WP8B
concerning the aeronautical radionavigation radars (WP8 B Documents
8B/137, 8B/137, 8B/139 (available from NTIA)). Generally, the results of
the tests show that the current I/N IPC of --6 dB is not sufficient to
protect radar operations in those bands and that the IPC should be no
higher than an I/N of --10 dB. The ITU Radiocommunication Assembly has
reviewed the contributions and the protection criteria in Rec. ITU-R
M.1464 has been changed to an I/N of --10 dB.

### Pulse-Like Interfering Signals

IPC for radiolocation and radionavigation receivers for pulse-like
interfering signals have not been specifically addressed by the ITU in
the M series of Recommendations. However, test results submitted to the
ITU by NTIA have shown that radars that contain Interference Rejection
(IR) circuitry and/or software can operate in the presence of other
similar low duty cycle (\< 2%) radars with I/N up to 60 dB without
detrimental effect (WP8B documents 8B/207 and 8B/124 (available from
NTIA)). These results have been published by the ITU as a Report.[^48]
Rec. ITU-R M.1372 contains methods for radars to operate in a more
efficient manner with other radars.[^49] This includes descriptions of
typical interference rejection mechanisms that are capable of limiting
the effects of pulsed interfering signals in radars.

### Impulse-Like Interfering Signals

Neither the ITU, ICAO, RTCA, RTCM, nor the IEC have published any
recommendations concerning IPC for impulse-like, ultrawideband (UWB)
interfering signals. However, ITU Task Group 1/8 has been formed by the
ITU to address the issue of UWB signal characteristics and protection
criteria. The ITU has directed that any compatibility studies between
UWB devices and systems in other services must be submitted through Task
Group 1/8.

In NTIA Special Publication 01-43, NTIA performed compatibility analyses
between federal government systems and UWB devices for the FCC UWB
rule-making.[^50] NTIA chose to use the existing and proposed ITU
thresholds for the radiodetermination receiver protection criteria which
was an I/N of --6 dB or --10 dB, as per Table 5-6.[^51]

The I/N values were based on the average interfering signal power within
the IF passband calculated with the RMS voltage. After the UWB
Rulemaking was completed, NTIA, USCG, and the British Coast Guard
performed interference susceptibility tests on maritime radionavigation
radars that operate in the 2900-3100 and 9200-9500 MHz bands with UWB
devices. The full results of those tests have been submitted to the ITU
and were used for modifying the Recommendations. Generally, the test
results show that marine radars in these bands require an I/N of --10 to
--6 dB based on average power of the UWB transmitter.

### Aeronautical Radionavigation Systems (other than radars using passive reflections) 

The IPCs for aeronautical radionavigation systems using transponders or
beacons are in the form of S/I, S/(N+I), an absolute interfering signal
power limit in dBm, or I/N. The IPCs for some of these systems are
published by the ITU, FAA, RTCA, and ICAO. These systems include the
Instrument Landing System (ILS) localizer and VOR, Distance Measuring
Equipment (DME), Air Traffic Control Radio Beacon (ATCRBS), and the
Microwave Landing System (MLS). IPCs for these systems are shown in
Table 5-2.

The FAA has developed procedures for coordinating the use and
positioning of VOR, DME, TACAN, and ILS localizer systems in FAA
publication 6050.32.[^52] The material contained in the document is
intended to be used by FAA personnel for determining frequency and/or
distance separations for these types of systems. The IPCs for these
systems, when considering interfering signals from another system of the
same type, are in the form of a desired-to-understand signal power ratio
(D/U). These D/U-s are based on an availability of 95 percent. The D/U-s
are specified for different frequency separations. The D/U is the
greatest when the systems are co-channel and is lessened as the
frequency separation increases.

Table 5-2

Aeronautical Radionavigation Protection Criteria

+----------------------+--------------------+-------------------------+
| System               | Frequency Band     | IPC                     |
+----------------------+--------------------+-------------------------+
| ILS                  | 108-112 MHz        | Signal Dependent, see   |
|                      |                    |                         |
| Localizer            |                    | ITU-R SM.1009-1,[^53]   |
|                      |                    |                         |
|                      |                    | ITU-R SM.1140[^54]      |
+----------------------+--------------------+-------------------------+
| ILS                  | 108-117.95 MHz     | Signal Dependent, see   |
|                      |                    |                         |
| VOR                  |                    | ITU-R SM.1009-1,        |
|                      |                    |                         |
|                      |                    | ITU-R SM.1140           |
+----------------------+--------------------+-------------------------+
| ILS                  | 74.8-75.2 MHz      | I/N ≤ 0 dB[^55]         |
|                      |                    |                         |
| Marker Beacon        |                    |                         |
+----------------------+--------------------+-------------------------+
| ILS                  | 328.6-335.4 MHz    | N/S                     |
|                      |                    |                         |
| Glide Slope          |                    |                         |
+----------------------+--------------------+-------------------------+
| DME                  | 962-1213 MHz       | I ≤ --99 dBm[^56]       |
+----------------------+--------------------+-------------------------+
| MLS                  | 5030-5091 MHz      | I ≤ --134 dBm[^57]      |
+----------------------+--------------------+-------------------------+
| Radar Altimeters     | 4200-4400 MHz      | S/(N+I) ≥12 dB for      |
|                      |                    | FM-CW type altimeters,  |
|                      |                    |                         |
|                      |                    | S/(N+I) ≥ 6 dB for      |
|                      |                    | Pulsed type altimeters  |
+----------------------+--------------------+-------------------------+
| ATCRBS               | 1030 and 1090 MHz  | S/I ≥ 12 dB for         |
|                      |                    | Interrogator[^58]       |
|                      |                    |                         |
|                      |                    | S/I ≥12 dB for          |
|                      |                    | Transponder[^59]        |
+----------------------+--------------------+-------------------------+

The IPC in Table 5-2 are for a continuous type of signal and are not
apportioned for interference allotment to other services. They are not
defined in terms of short- and long-term criteria. The references for
each system in Table 5-2 further define the exact nature of the
interfering signals.

## RadioNAVIGATION-Satellite Service

The primary systems operating in the radionavigation satellite service
(RNSS) are GPS, launched and maintained by the United States, and
GLONASS, launched and maintained by the Russian Federation. In addition
there are space-based augmentation systems (SBAS) and ground-based
augmentation systems (GBAS) operating in the RNSS frequency bands.[^60]
These augmentation systems provide additional information that enhances
the integrity, accuracy, continuity, and reliability of the RNSS
systems. The GPS and GLONASS RNSS systems allow users equipped with
appropriate receivers to determine position, velocity, and time (PVT)
information free of charge.

GPS is a Code Division Multiple Access (CDMA) based system. That is,
each satellite broadcasts ranging signals with different coding
sequences to allow the receiver to access the individual satellite
signals. GLONASS is a Frequency Division Multiple Access (FDMA) based
system. That is, each satellite that is visible to a user receiver
broadcasts ranging signals on different frequencies to allow access to
individual satellite signals. The various ranging signals are coded at
clock rates from 1.023 MHz up to 10.23 MHz.

The frequency bands allocated internationally to the RNSS are 1164-1215
MHz, 1215-1350 MHz, 1559-1610 MHz, and 5000-5030 MHz. GPS provides a
ranging signal centered at 1227.6 MHz (L2) and two ranging signals
centered at 1575.42 MHz (L1). In the future, GPS is to add ranging
signals at 1176.45 MHz (L5) and 1227.6 MHz for civil use. Additional
ranging signals will also be added at L1 for military use. GLONASS
provides ranging signals in the 1559-1610 MHz and 1215-1350 MHz RNSS
bands.

The European Union is also developing a RNSS system referred to as
Galileo that will provide ranging signals in the three frequency bands
allocated for RNSS. Galileo will use CDMA and will provide ranging
signals for both public and restricted use. The operators of this system
will charge some kind of user fee or excise tax for the service.

### IPC Values for GPS Receivers

GPS receivers are used in a myriad of applications including navigation
(aviation, space, maritime, rail, and vehicular), position determination
(surveying, asset tracking, enhanced-911), and timing (banking, power
distribution, Internet synchronization). The IPC values for GPS
receivers will depend on: 1) the receiver application; 2) the category
of interfering signal (noise-like, CW, or pulse-like); 3) receiver
architecture (coarse/acquisition (C/A), semi-codeless, narrow correlator
C/A code); and 4) performance criteria (break-lock, reacquisition,
pseudorange error).

Since the IPC for GPS receivers are better organized by the type of
application rather than the type of interfering signal, the IPC are
presented below for Aviation, Maritime, Land-based, and Space-based uses
of RNSS.

#### Aviation Applications  {#aviation-applications .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

The ITU-R and the RTCA are the primary sources of published IPC values
for GPS receivers used in aeronautical applications. General receiver
characteristics and IPC values are contained in Rec. ITU-R M.1477 for
aeronautical and ground-based receivers. [^61] The RTCA has also
published IPC values for GPS receivers that are used for aviation
applications in RTCA DO-229B. [^62]

The GPS IPC in Rec. ITU-R M.1477 are based on a minimum desired signal
and are specified for the signal tracking and signal acquisition modes
of a GPS receiver. The IPC are applicable to GPS receivers used for
airborne navigation (en-route and Category I precision approach)[^63]
and GPS receivers used in a ground-based network (WAAS reference
stations). The airborne receivers are intended for use with the C/A code
signal at 1575.42 MHz. The ground-based network receiver employs the
semi-codeless architecture that processes both the C/A code and
Precision code (P-code) signals at 1575.42 MHz and the P-code signal at
1227.6 MHz. The P-code signals are cross-correlated (does not require
knowledge of the coding sequence) to provide a measure of the
ionospheric delay to improve the accuracy of the range determination.
The cross-correlation is made possible by the fact that the two P-code
signals from a given satellite have identical, synchronized code
sequences. For each of the receivers addressed in Rec. ITU-R M.1477, IPC
are specified for narrowband (CW) and wideband (noise-like) interfering
signals. In this context, narrowband is defined as a bandwidth of less
than 700 Hz, and wideband is defined as a bandwidth of between 100 kHz
to 1 MHz.

The GPS IPC presented in Rec. ITU-R M.1477 are specified in terms of
interfering signal power threshold and are summarized in Table 5-3.
These IPC are referenced to the input of the GPS receiver and are based
on a minimum available GPS C/A code signal level of --134.5 dBm (--130
dBm minimum guaranteed signal level into a --4.5 dBic antenna). The
associated performance criteria for GPS aeronautical receivers are in
the form of pseudorange error.

The ITU-R is the primary source of published IPC values for GLONASS
receivers used in aeronautical applications. General receiver
characteristics and IPC are contained in Rec. ITU-R M.1477 for
aeronautical receivers. Rec. ITU-R M.1477 specifies IPC applicable to
four types of GLONASS aeronautical receivers. These receivers are used
for en-route navigation and Category I approaches, SBAS, and Category
I/II/III approaches. The GLONASS IPC values in Rec. ITU-R M.1477 are
contained in Table 5-4.

Table 5-3

ITU-R Aeronautical GPS Receiver IPC Values for Wideband

and Narrowband Interfering Signals

  ---------------------------- ------------------- -----------------------
  **Receiver Application and   **Interfering       
  Mode**                       Signal Power        
                               Threshold**         

                               **Narrowband        **Wideband Signal**
                               Signal**            

  Airborne Navigation                              

  Tracking Mode                --150.5 dBW         --140.5 dBW/MHz

  Acquisition Mode             --156.5 dBW         --146.5 dBW/MHz

  Ground-Based Network                             

  Tracking Mode                --154.5 dBW         --146.5 dBW/MHz

  Acquisition Mode             --156.5 dBW         --146.5 dBW/MHz

  Note: The IPC values in this                     
  table are in terms of the                        
  highest aggregate                                
  interfering signal power at                      
  the receiver input at which                      
  the receiver is to operate                       
  without unacceptable                             
  performance degradation.                         
  ---------------------------- ------------------- -----------------------

Table 5-4

ITU-R Aeronautical GLONASS Receiver IPC Values for Wideband

and Narrowband Interfering Signals

  ----------------------- ----------------------- -----------------------
  **Receiver Mode**       **Interfering Signal    
                          Power Threshold**       

                          **Narrowband Signal**   **Wideband Signal**

  Tracking Mode           --149 dBW               --146 dBW/MHz

  Acquisition Mode        --155 dBW               --152 dBW/MHz

  Note: The IPC values in                         
  this table already take                         
  into account the                                
  effects of GLONASS                              
  intra-system                                    
  interference based on                           
  analysis of random                              
  codes. The IPC values                           
  must account for the                            
  aggregate of all other                          
  interfering signals.                            
  ----------------------- ----------------------- -----------------------

The RTCA IPC thresholds are meant to be applied to only aviation GPS
receivers. RTCA has developed IPC for initial satellite acquisition,
satellite reacquisition, and steady state conditions. They are shown
below in Table 5-5, and apply to broadband noise-like interfering signal
sources centered at the L1 frequency of 1575.42 MHz. The test procedures
for the RTCA IPC are quite extensive and detailed. RTCA DO-229B should
be thoroughly reviewed before application of these IPC. The IPC values
specified by RTCA are referenced to the input of the GPS receiver and
are based on a minimum available GPS C/A code signal level of --134.5
dBm (--130 dBm minimum guaranteed signal level into a --4.5 dBic
antenna).

RTCA has published IPC for CW-like signals for aviation GPS receivers in
DO-229B that are shown below in Table 5-6. They only apply to receiver
steady state conditions.

Table 5-5

Noise-like IPC values for Aviation GPS Receivers

+------------------------+---------------------------------------------+
| Initial Satellite      |                                             |
| Acquisition ^i^        |                                             |
+------------------------+---------------------------------------------+
| Noise Bandwidth        | Total Power Threshold                       |
+------------------------+---------------------------------------------+
| 100 kHz                | I --116.5 dBm                               |
|                        |                                             |
| 20 MHz                 | I --103.5 dBm                               |
+------------------------+---------------------------------------------+
| > ^i^ Single Trial     |                                             |
| > Pass criteria: The   |                                             |
| > sensor provides a    |                                             |
| > valid position fix   |                                             |
| > within 5 minutes and |                                             |
| > maintains an         |                                             |
| > accuracy of 15       |                                             |
| > meters for 95        |                                             |
| > percent of the time  |                                             |
| > for the next 60      |                                             |
| > seconds.             |                                             |
+------------------------+---------------------------------------------+
| Satellite              |                                             |
| Reacquisition^ii^      |                                             |
+------------------------+---------------------------------------------+
| Noise Bandwidth        | Total Power Threshold                       |
+------------------------+---------------------------------------------+
| 100 kHz                | I --110.5 dBm                               |
|                        |                                             |
| 20 MHz                 | I --97.5 dBm                                |
+------------------------+---------------------------------------------+
| > ^ii^ Single Trial    |                                             |
| > Pass criteria: The   |                                             |
| > sensor includes the  |                                             |
| > reacquired satellite |                                             |
| > into the position    |                                             |
| > solution within 10   |                                             |
| > seconds and          |                                             |
| > maintains an         |                                             |
| > accuracy of 15       |                                             |
| > meters for 95        |                                             |
| > percent of the time  |                                             |
| > for the next 60      |                                             |
| > seconds.             |                                             |
+------------------------+---------------------------------------------+
| Steady State Accuracy  |                                             |
| IPC^iii^               |                                             |
+------------------------+---------------------------------------------+
| Noise Bandwidth        | Total Power Threshold                       |
+------------------------+---------------------------------------------+
| 100 kHz                | I --110.5 dBm                               |
|                        |                                             |
| 20 MHz                 | I --97.5 dBm                                |
+------------------------+---------------------------------------------+
| > ^iii^ The pass/fail  |                                             |
| > criteria are based   |                                             |
| > on the normalized    |                                             |
| > RMS range error      |                                             |
| > statistic of the     |                                             |
| > satellite            |                                             |
| > pseudorange.         |                                             |
+------------------------+---------------------------------------------+

Table 5-6

CW IPC Values for Aviation GPS Receivers

  ------------------- --------------------------- ------------------------
  Frequency (MHz)     Interfering Signal Power    Corresponding I/S (dB)
                      Threshold (dBm)             

  1525.0              --12.0                      122.5

  1555.42             --89.5                      45.0

  1575.42             --120.5                     14.0

  1595.42             --89.5                      45.0

  1610.0              --30.0                      104.5

  1618.0              --12.0                      122.5

  1626.0              +8.0                        142.5

  The pass/fail                                   
  criteria are based                              
  on the normalized                               
  RMS range error                                 
  statistic of the                                
  satellite                                       
  pseudorange.                                    
  ------------------- --------------------------- ------------------------

RTCA has published IPC in DO-229B for pulse-like signals for aviation
GPS receivers that are summarized in Table 5-7. These IPC apply only to
steady state conditions. These IPC are specified as a function of
interfering pulse width, duty cycle, and carrier power.

Table 5-7

Pulsed Interfering Signal IPC for Aviation GPS Receivers

+----------------+-----------+-------+-------+-------+-------+--------+
| Frequency      | GPS only  |       |       | GPS   |       |        |
| (MHz)          | In        |       |       | and   |       |        |
|                | terfering |       |       | WAAS  |       |        |
|                | Signal    |       |       | I     |       |        |
|                | Pulse     |       |       | nterf |       |        |
|                | Width     |       |       | ering |       |        |
|                |           |       |       | S     |       |        |
|                |           |       |       | ignal |       |        |
|                |           |       |       | Pulse |       |        |
+----------------+-----------+-------+-------+-------+-------+--------+
| 1575.42        | Pulse     | I 20  | Duty  | Pulse | I 20  | Duty   |
|                | width     | dBm   | Cycle | Width | dBm   | Cycle  |
|                |           |       |       |       |       |        |
|                | 1         |       | 10 %  | 125   |       | 10 %   |
|                | mi        |       |       | µS    |       |        |
|                | llisecond |       |       |       |       |        |
+----------------+-----------+-------+-------+-------+-------+--------+
| The pass/fail  |           |       |       |       |       |        |
| criteria are   |           |       |       |       |       |        |
| based on the   |           |       |       |       |       |        |
| normalized RMS |           |       |       |       |       |        |
| range error    |           |       |       |       |       |        |
| statistic of   |           |       |       |       |       |        |
| the satellite  |           |       |       |       |       |        |
| pseudorange.   |           |       |       |       |       |        |
+----------------+-----------+-------+-------+-------+-------+--------+

#### Maritime Applications  {#maritime-applications .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

Maritime GPS receivers are used for navigation in constricted waterways,
harbor navigation, docking operations, navigation around bridges, lock
operations. IEC has adopted a maximum permissible interference level
based on the levels developed by RTCA for aviation receivers.[^64] The
IPC are specified for a GPS L1 narrow correlator C/A code receiver. For
in-band broadband noise-like interfering signals, the IEC has specified
that the interfering signal power density should not exceed --140
dBW/MHz in a GPS maritime receiver operating in the tracking mode.

#### Space Based Applications {#space-based-applications .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

GPS and GLONASS receivers are used for navigation of spacecraft
(real-time and post-processed), spacecraft attitude determination, orbit
determination, time synchronization, launch vehicle range safety, and
launch vehicle guidance. GPS receivers for space-based applications use
the C/A code signal at 1575.42 MHz and the P-code at 1227.6 MHz. IPC for
space-based GPS and GLONASS receivers are provided in Rec. ITU-R
M.1479.[^65]

The GPS IPC for aggregate interfering signal power spectral density at
the antenna output from Rec. ITU-R M.1479 are: --135 dBW/MHz for
wideband interfering signals and --135 dBW/100 kHz for narrowband
interfering signals. These IPC were derived from the 34 dB(Hz)
carrier-to-noise density threshold for L1 C/A code acquisition and
assume certain desired GPS signal power levels and GPS co-channel
interfering signal levels experienced by receivers in low-earth orbit
(receiver \< 2000 km altitude).

The front-end of a GPS receiver is affected by interfering signals in
two ways. The first mechanism affects the high-level limiter diode in
the RF front-end. The diode will saturate and prevent burnout of the
following receiver stages. Rec. ITU-R M.1479 specifies a preamplifier
limiting level of --70 dBW, which causes a temporary loss of signal. If
the average RF power at the receiver input exceeds 0 dBW or peak RF
power exceeds 10 dBW, the high-level limiter diode may fail because of
burnout.

In Rec. ITU-R M.1479, the in-band wideband interfering signal power
density at the receiving antenna output of a GLONASS space-based
receiver should not exceed --140 dBW/MHz.

**5.4 Summary**

Table 5-10 presents a summary of IPC for the radiodetermination
services.

+---------+-------+---------+---+------+----+-----------+----------+
| Systems | Freq  | Inter   |   | R    | \% | Source    | Comments |
| S       | uency | ference |   | efer | Ti | Documents |          |
| ervices | Bands | Pro     |   | ence | me |           |          |
|         |       | tection |   | b    |    |           |          |
|         |       |         |   | andw |    |           |          |
|         |       |         |   | idth |    |           |          |
+=========+=======+=========+===+======+====+===========+==========+
|         |       | C       | P |      |    |           |          |
|         |       | W/Noise | u |      |    |           |          |
|         |       |         | l |      |    |           |          |
|         |       |         | s |      |    |           |          |
|         |       |         | e |      |    |           |          |
|         |       |         | O |      |    |           |          |
|         |       |         | t |      |    |           |          |
|         |       |         | h |      |    |           |          |
|         |       |         | e |      |    |           |          |
|         |       |         | r |      |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Aeron   | 74.8  | I/N ≤ 0 | N | Sy   | N  | RTCA      | None     |
| autical | -75.2 | dB      | / | stem | /S | DO-143,   |          |
| Ra      | MHz   |         | S | IF   |    | NTIA Tech |          |
| dionavi |       |         |   | B    |    | Report    |          |
| gation\ |       |         |   | andw |    |           |          |
| (ILS    |       |         |   | idth |    |           |          |
| Beacon) |       |         |   |      |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radiol  | 42    | I/N ≤   | N | Sy   | N  | Rec.      | None     |
| ocation | 0-450 | --6 dB  | / | stem | /S | ITU-R     |          |
|         | MHz   |         | S | IF   |    | M.1462    |          |
|         |       |         |   |      |    |           |          |
|         |       |         |   | B    |    |           |          |
|         |       |         |   | andw |    |           |          |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Aeron   | 962   | I ≤     | N | Sy   | N  | RTCA      | none     |
| autical | -1213 | --99    | / | stem | /S | DO-189,   |          |
| R       | MHz   | dBm     | S | IF   |    | NTIA RPT  |          |
| adionav |       |         |   | B    |    | 01-143    |          |
| igation |       |         |   | andw |    |           |          |
| (DME)   |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Aeron   | 1030  | S/I ≤   | N | Sy   | N  | RTCA      | IPC same |
| autical | and   | 12 dB   | / | stem | /S | DO-181A,\ | for      |
| r       | 1090  |         | S | IF   |    | F         | tra      |
| adionav | MHz   |         |   | B    |    | AA-E-2716 | nsponder |
| igation |       |         |   | andw |    |           | and      |
| (       |       |         |   | idth |    |           | inte     |
| ATCRBS) |       |         |   |      |    |           | rrogator |
+---------+-------+---------+---+------+----+-----------+----------+
| Radio   | All   | I/N ≤   | N | Sy   | N  | Rec.      | General  |
| determi | u     | --6 dB  | / | stem | /S | ITU-R     | ITU-R    |
| na-tion | nless |         | S | IF   |    | M.1461    | Recomm   |
|         | othe  |         |   |      |    |           | endation |
|         | rwise |         |   | B    |    |           | for      |
|         | noted |         |   | andw |    |           | radars   |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radio   | 1215  | I/N ≤   | N | Sy   | N  | Rec.      | None     |
| determi | -1400 | --6 dB  | / | stem | /S | ITU-R     |          |
| na-tion | MHz   |         | S | IF   |    | M.1463    |          |
|         |       |         |   | B    |    |           |          |
|         |       |         |   | andw |    |           |          |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| R       | 2700  | I/N ≤   | N | Sy   | N  | Rec.      | None     |
| adionav | -2900 | --10 dB | / | stem | /S | ITU-R     |          |
| igation | MHz   |         | S | IF   |    | M.1464    |          |
| and     |       |         |   | B    |    |           |          |
| Meteoro |       |         |   | andw |    |           |          |
| logical |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| M       | 2900  | I/N ≤   | N | Sy   | N  | Rec.      | Revision |
| aritime | -3100 | --6 dB  | / | stem | /S | ITU-R     | underway |
| R       | MHz   |         | S | IF   |    | M.1313,\  | in ITU-R |
| adionav |       |         |   | B    |    | NTIA RPT  | WP8B     |
| igation |       |         |   | andw |    | 01-143    |          |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radio   | 2900  | I/N ≤   | N | Sy   | N  | Rec.      | Revision |
| determi | -3100 | --6 dB  | / | stem | /S | ITU-R     | underway |
| na-tion | MHz   |         | S | IF   |    | M.1460    | in ITU-R |
| and     |       |         |   | B    |    |           | WP8B     |
| Meteoro |       |         |   | andw |    |           |          |
| logical |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radio   | 3100  | I/N ≤   | N | Sy   | N  | Rec.      | None     |
| determi | -3700 | --6 dB  | / | stem | /S | ITU-R     |          |
| na-tion | MHz   |         | S | IF   |    | M.1465    |          |
|         |       |         |   | B    |    |           |          |
|         |       |         |   | andw |    |           |          |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radar   | 4200  | S/(N+I) | N | Sy   | N  | Manu      | Not much |
| Alt     | -4400 | ≥ 12 dB | / | stem | /S | facturers | inf      |
| imeters | MHz   | CW      | S | IF   |    | Brochures | ormation |
|         |       | S       |   | B    |    |           | a        |
|         |       | ystems, |   | andw |    |           | vailable |
|         |       |         |   | idth |    |           |          |
|         |       | S/(N+I) |   |      |    |           |          |
|         |       | ≥ 6 dB  |   |      |    |           |          |
|         |       | Pulsed  |   |      |    |           |          |
|         |       | Systems |   |      |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Aeron   | 5030  | I ≤     | N | 26   | N  | ICAO      | Includes |
| autical | -5091 | --134   | / | kHz  | /S | Radion    | 6 dB of  |
| R       | MHz   | dBm     | S |      |    | avigation | safety   |
| adionav |       |         |   |      |    | Aids      | Margin   |
| igation |       |         |   |      |    | Annex 10  |          |
| (MLS)   |       |         |   |      |    | Vol. 1,   |          |
|         |       |         |   |      |    |           |          |
|         |       |         |   |      |    | NTIA RPT  |          |
|         |       |         |   |      |    | 01-143    |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radiolo | 5280  | I/N ≤   | N | Sy   | N  | Rec.      | New      |
| cation, | -5850 | --6 dB  | / | stem | /S | ITU-R     | Recomm   |
| Aeron   | MHz   |         | S | IF   |    | M.1638    | endation |
| autical |       |         |   | B    |    |           | in June  |
| Ra      |       |         |   | andw |    |           | 2003     |
| dionavi |       |         |   | idth |    |           |          |
| gation, |       |         |   |      |    |           |          |
| and     |       |         |   |      |    |           |          |
| Meteoro |       |         |   |      |    |           |          |
| logical |       |         |   |      |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radio   | 8500- | I/N ≤   | N | Sy   | N  | REC.      | Pre      |
| determi | 10500 | --6 dB  | / | stem | /S | ITU-R     | liminary |
| na-tion | MHz   |         | S | IF   |    | M.XXX     | DNR In   |
|         |       |         |   | B    |    |           | ITU WP8B |
|         |       |         |   | andw |    |           |          |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| R       | 13.   | I/N ≤   | N | Sy   | N  | Rec.      | None     |
| adionav | 75-14 | --6 dB  | / | stem | /S | ITU-R     |          |
| igation | GHz   |         | S | IF   |    | M.1644    |          |
| and     |       |         |   | B    |    |           |          |
| R       |       |         |   | andw |    |           |          |
| adionav |       |         |   | idth |    |           |          |
| igation |       |         |   |      |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| R       | 31.8  | I/N ≤   | N | Sy   | N  | Rec.      | None     |
| adionav | -34.4 | --6 dB  | / | stem | /S | ITU-R     |          |
| igation | GHz   |         | S | IF   |    | M.1466    |          |
|         |       |         |   | B    |    |           |          |
|         |       |         |   | andw |    |           |          |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+
| Radio   | 33    | I/N ≤   | N | Sy   | N  | Rec.      | None     |
| determi | .4-36 | --6 dB  | / | stem | /S | ITU-R     |          |
| na-tion | GHz   |         | S | IF   |    | M.1640    |          |
|         |       |         |   | B    |    |           |          |
|         |       |         |   | andw |    |           |          |
|         |       |         |   | idth |    |           |          |
+---------+-------+---------+---+------+----+-----------+----------+

REFERENCES

#  BROADCASTING AND BROADCASTING-SATELLITE SERVICES

## Introduction

This section describes the IPC from various sources for the broadcasting
service (BS) and broadcasting-satellite service (BSS). Although there
are several frequency bands below 30 MHz allocated to terrestrial
broadcasting for federal use, none are allocated for use by the federal
government above 30 MHz for either terrestrial or satellite
broadcasting. The IPC are provided herein to facilitate sharing
feasibility studies with non-federal BS or BSS receivers. With few
exceptions, available IPC values for the BS and BSS are limited to
consideration of interfering signals from within the same radio service.
The IPC for the BS and BSS are generally specified in terms of C/I
values.

## Broadcasting Service

The BS consists of radio or television broadcasting from terrestrial
stations for direct reception by the general public.[^66] The BS is
presently limited to the frequency bands between 30 MHz and 30 GHz shown
in Table 6-1.[^67]

Table 6‑1

U.S. BS Allocations between 30 MHz and 30 GHz

  ------------------------- ---------------------------------------------
  Bands (MHz)               Service

  54-72                     TV (channels 2-4)

  76-88                     TV (channels 5-6)

  88-108                    FM radio (channels 201-300)

  174-216                   TV (channels 7-13)

  470-608                   TV (channels 14-36)

  614-746                   TV (channels 38-59)

  746-806                   TV (channels 60-69)[^68]
  ------------------------- ---------------------------------------------

This table shows all of the BS allocations in the United States within
the defined frequency range, which are discussed in the following
subsections.

### Broadcast Television

Spectrum allocated for broadcast television is divided into 6 MHz
channels ranging from television channels 2 through 69. Conventional
analog transmissions will be replaced by digital television (DTV) over
time. Under the transition plan, broadcasters are assigned a locally
vacant channel for DTV while temporarily keeping their current analog
channel.

The IPC for television are contained primarily in ITU-R Recommendations
and FCC Rules (Title 47 CFR, Part 73). In the ITU-R Recommendations, the
IPC are listed for 3 different digital television standards: ATSC
(Advanced Television Systems Committee), DVB-T (Digital Video
Broadcasting-Terrestrial), and ISDB-T (Integrated Service Digital
Broadcasting-Terrestrial). DVB-T was adopted by Europe, Africa,
Australia, and Greenland. ISDB-T was adopted by Japan. ATSC was adopted
by the United States and Canada, thus, this report will focus on ATSC
IPC. Analog TV resolutions of 525 and 625 lines are addressed in the
ITU, but this report will address only the 525 line M/NTSC analog
standard used within the United States.

IPC for DTV have been developed for continuous and tropospheric
interfering signals. Continuous interfering signals are defined as
long-term interfering signals that are exceeded for 50% or more of the
time and generally serve as the baseline for establishing protection
criteria. Tropospheric interfering signals are defined as short-term
interfering signals that are exceeded for no more than 1 to 10% of the
time. In all cases, the IPC for short-term tropospheric interference
permit a lower C/I, than that for continuous interfering signals.

#### Television IPC in ITU-R Recommendations {#television-ipc-in-itu-r-recommendations .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

Rec. ITU-R BT.1368 provides IPC for the planning of DTV with respect to
analog television.[^69] Different IPC are required for planning DTV
because the geographic distributions of field strength for DTV signals
are not the same as those applicable to analog television signals. Table
6-2 defines IPC for protection of ATSC from ATSC for co-channel and
adjacent channel conditions.

Table 6‑2

IPC for Protection of ATSC from ATSC Interference

  ----------------------------------- -----------------------------------
  Unwanted Digital Channel            Continuous and Tropospheric
                                      Interfering Signals

  Lower Adjacent                      C/I ≥ --27 dB

  Co-Channel                          C/I ≥ 15, 19^i^ dB

  Upper Adjacent                      C/I ≥ --27 dB

  ^i^Based on I/N = 0 dB              
  ----------------------------------- -----------------------------------

Table 6-3 defines IPC for protection of ATSC from NTSC for cochannel and
adjacent channel conditions.

Table 6‑3

IPC for Protection of ATSC from NTSC Interference

  ------------------------------------ ----------------------------------
  Unwanted Digital Channel             Continuous and Tropospheric
                                       Interfering Signals

  Lower Adjacent                       C/I ≥ --48 dB

  Co-Channel                           C/I ≥ 2, 7^i^ dB

  Upper Adjacent                       C/I ≥ --49 dB

  ^i^Based on use of a comb filter and 
  C/N ≥ 19 dB                          
  ------------------------------------ ----------------------------------

Table 6-4 defines IPC for protection of NTSC from ATSC under cochannel
and adjacent channel sharing conditions and only short-term IPC are
specified.

.

Table 6‑4

IPC for Protection of NTSC from ATSC Interference

+--------------------------------+-------------------------------------+
| Unwanted Digital Channel       | Tropospheric Interfering Signals    |
|                                |                                     |
|                                | (1-10% of time)                     |
+--------------------------------+-------------------------------------+
| Lower Adjacent                 | C/I ≥ --16 dB                       |
+--------------------------------+-------------------------------------+
| Co-Channel                     | C/I ≥ 34 dB                         |
+--------------------------------+-------------------------------------+
| Upper Adjacent                 | C/I ≥ --17, --12^i^ dB              |
+--------------------------------+-------------------------------------+
| ^i^For protection of NTSC      |                                     |
| sound signals                  |                                     |
+--------------------------------+-------------------------------------+

In the case of interfering signals using an upper adjacent digital
channel into an NTSC channel in Table 6-4, the NTSC audio signal
degrades more than the video signal and requires a more restrictive IPC.

Rec. ITU-R BT.655 lists IPC for protection of analog television from
analog vision and sound signals.[^70] Unless otherwise stated, these IPC
address tropospheric interfering signals. Where IPC for continuous
interfering signals are not available, yet required due to substantially
non-fading unwanted signals, the tropospheric values of Table 6-5
increased by 10 dB may be used.

Table 6‑5

IPC for Protection of NTSC from NTSC Interference

+----------------------------+-----------------------------------------+
| Unwanted Channel           | Tropospheric Interfering Signals        |
|                            |                                         |
|                            | (1-10% of Time)                         |
+----------------------------+-----------------------------------------+
| Lower Adjacent             | C/I ≥ --13 dB                           |
+----------------------------+-----------------------------------------+
| Co-Channel                 | C/I ≥ 45 dB                             |
+----------------------------+-----------------------------------------+
| Upper Adjacent             | C/I ≥ --10 dB                           |
+----------------------------+-----------------------------------------+

When the interfering source is a CW signal, a vision signal positive
modulated, or FM-sound, and the wanted signal is a vision signal
negative modulated, the IPC in Table 6-6 apply.[^71] If the interferer
is a vision signal negative modulated or an AM-sound signal, a --2 dB
and +4 dB offset, respectively, can be applied to the IPC values in
Table 6-6.

Table 6‑6

IPC for Protection of Negative Modulated Vision NTSC Signal from CW,
Positive Modulated Vision NTSC, and FM Sound Signals

  ----------- ------- ------- ------- ----- ----- ----- ----- ----- ----- ----- -----
  Δf (MHz)    --1.5   --1.0   --.75   0.3   1.0   2.5   3.0   3.5   3.7   4.1   4.5

  C/I (dB)    0       30      40      50    50    37    45    50    50    45    15

  Δf =                                                                          
  unwanted                                                                      
  carrier                                                                       
  frequency                                                                     
  minus                                                                         
  wanted                                                                        
  carrier                                                                       
  frequency                                                                     
  ----------- ------- ------- ------- ----- ----- ----- ----- ----- ----- ----- -----

Table 6-7 describes IPC for the case of a wanted FM sound signal and
unwanted CW or FM sound carrier with various frequency offsets.

Table 6‑7

IPC for an NTSC Wanted FM Sound Signal Interfered\
with by an Unwanted CW or FM Sound Carrier

  -------- ------------------- ------------ ---------- ---------- -------------
  Wanted                       Frequency                          
  Sound                        Difference                         
  Signal                       between                            
                               Unwanted                           
                               Carrier and                        
                               Wanted Sound                       
                               Carrier                            
                               (kHz)                              

                               0            15         50         250

  FM       Tropospheric (C/I): 32 dB        30 dB      22 dB      --6 dB

           Continuous (C/I):   39 dB        35 dB      24 dB      --6 dB
  -------- ------------------- ------------ ---------- ---------- -------------

#### Television IPC in FCC Rules {#television-ipc-in-fcc-rules .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

Section 73.525 of the FCC Rules defines protection requirements for NTSC
TV channel 6 from FM radio signals for cochannel and adjacent channel
operation as shown in Table 6-8.[^72]

Table 6‑8

IPC for Protection of NTSC Channel 6 from FM Radio Interference

  ----------------------------------------------------- -----------------
  **Unwanted Channel**                                  C/I

  **Co-channel:**                                       

  no offset                                             39 dB

  normal offset^i^                                      22 dB

                                                        

  **Adjacent-Channel**:                                 --12 dB

  ^i^ TV carrier offset by 10 kHz (Section 73.606)      
  ----------------------------------------------------- -----------------

Section 73.623 of the FCC Rules defines IPC for various combinations of
analog and DTV as shown in Table 6-9.[^73]

Table 6‑9

IPC for Protection of Analog and DTV

  ---------------------------------------------- ------------------------
  **Unwanted Channel**                           C/I

  Co-channel:                                    

  DTV into analog TV                             34 dB

  Analog TV into DTV                             2 dB

  DTV into DTV                                   15 dB

                                                 

  First Adjacent Channel:                        

  Lower DTV into analog TV                       --14 dB

  Upper DTV into analog TV                       --17 dB

  Lower analog TV into DTV                       --48 dB

  Upper analog TV into DTV                       --49 dB

  Lower DTV into DTV                             --28 dB

  Upper DTV into DTV                             --26 dB
  ---------------------------------------------- ------------------------

According to Section 90.545 of the FCC regulations, public safety base,
control, and mobile transmitters in the 764-776 MHz and 794-806 MHz
bands are subject to the IPC to protect existing analog TV and DTV
broadcast stations transmitting on TV channels 62, 63, 64, 65, 67, 68,
and 69 as described in Table 6-10.[^74]

Table 6‑10

IPC for Protection of Analog and DTV Stations\
from Public Safety Transmissions in 764-776 and 794-806 MHz Bands

+-------------------------------------+--------------------------------+
| **Unwanted Channel**                | **C/I**                        |
+-------------------------------------+--------------------------------+
| **Co-channel:**                     |                                |
+-------------------------------------+--------------------------------+
| Analog TV^i^                        | 40 dB                          |
+-------------------------------------+--------------------------------+
| DTV^ii^                             | 17 dB                          |
+-------------------------------------+--------------------------------+
|                                     |                                |
+-------------------------------------+--------------------------------+
| **First Adjacent Channel:**         |                                |
+-------------------------------------+--------------------------------+
| Analog TV^i^                        | 0 dB                           |
+-------------------------------------+--------------------------------+
| DTV^ii^                             | --23 dB                        |
+-------------------------------------+--------------------------------+
| ^i^ At the hypothetical Grade B     |                                |
| contour (64 dBμV/m) (85.5 km) of    |                                |
| the analog TV station               |                                |
|                                     |                                |
| ^ii^ At the equivalent Grade B      |                                |
| contour (41 dBμV/m) (88.5 km) of    |                                |
| the DTV station                     |                                |
+-------------------------------------+--------------------------------+

### FM Radio Broadcast 

There is a similar thrust toward digital in the FM radio broadcast band
except that there are no plans for reallocation. There are and will
continue to be 101 FM radio channels numbered from 200 to 300 with each
channel being 200 kHz wide. Channel 200 is centered at 87.9 MHz; channel
201 is 88.1 MHz, and so forth through channel 300, which is centered at
107.9 MHz. Channels 200 to 220 (87.9 to 91.9 MHz) are available for
non-commercial educational purposes.[^75] The transition to digital will
allow broadcasters to transmit both analog and digital versions of their
signal in the same 200 kHz channel. This method, called IBOC (in-band
on-channel), allows FM stations to transmit the digital signal on the
sidebands above and below the FM band center frequency. During hybrid
operation, existing (analog) receivers still continue to receive the
analog signal. New receivers being developed are expected to incorporate
both modes of reception. If the digital signal cannot be decoded or is
lost by the receiver, the new receiver will automatically switch to the
analog FM signal.

The following subsections list IPC (C/I) of radio frequency signals at
the receiver input, and are specifically chosen such that they achieve a
defined level of demodulated audio frequency S/I at the receiver output.

#### Broadcast FM Radio IPC in ITU-R Recommendations {#broadcast-fm-radio-ipc-in-itu-r-recommendations .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

Rec. ITU-R BS.412 shows a list of IPC to protect monophonic and
stereophonic desired signals from continuous and tropospheric
interfering signal sources.[^76] The interfering signal sources are
other broadcast FM radio signals. As expected the IPC shown in Table
6-11 decrease with increasing frequency separation between the desired
and undesired carriers, with the exception of the stereophonic case
where the IPC decreases only after first increasing through the first 50
kHz of separation. The 75 kHz maximum deviation associated with the IPC
in Table 6-11 corresponds to the limit for FM radio broadcasting within
the United States.[^77]

Table 6‑11

FM Radio Broadcasting IPC

  ------------- ------------- -------------- -------------- --------------
  Carrier       C/I (dB)                                    
  Frequency     Using Maximum                               
  Separation    Frequency                                   
  (kHz)         Deviation of                                
                ±75 kHz                                     

                Monophonic                   Stereophonic   

                Continuous    Tropospheric   Continuous     Tropospheric

  0\            36.0\         28.0\          45.0\          37.0\
  25\           31.0\         27.0\          51.0\          43.0\
  50\           24.0\         22.0\          51.0\          43.0\
  75\           16.0\         16.0\          45.0\          37.0\
  100\          12.0\         12.0\          33.0\          25.0\
  125\          9.5\          9.5\           24.5\          18.0\
  150\          8.0\          8.0\           18.0\          14.0\
  175\          7.0\          7.0\           11.0\          10.0\
  200\          6.0\          6.0\           7.0\           7.0\
  225\          4.5\          4.5\           4.5\           4.5\
  250\          2.0\          2.0\           2.0\           2.0\
  275\          --2.0\        --2.0\         --2.0\         --2.0\
  300\          --7.0\        --7.0\         --7.0\         --7.0\
  325\          --11.5\       --11.5\        --11.5\        --11.5\
  350\          --15.0\       --15.0\        --15.0\        --15.0\
  375\          --17.5\       --17.5\        --17.5\        --17.5\
  400           --20.0        --20.0         --20.0         --20.0
  ------------- ------------- -------------- -------------- --------------

#### Broadcast FM Radio IPC in FCC Regulations {#broadcast-fm-radio-ipc-in-fcc-regulations .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

The FCC Part 73 Rules define sharing criteria between FM radio stations
in terms of minimum distance separations and do not specify general IPC
values. However, as an exception defined in Sections 73.213 and 73.215,
stations at locations authorized prior to November 16, 1964, that did
not meet the separation distances required by Section 73.207 and have
remained continuously short-spaced[^78] since that time must meet the
requirements defined in TABLE 6-12.[^79]

TABLE 6‑12

IPC for Protection of Broadcast Radio from\
other Broadcast Radio Stations[^80]

+--------------------------------------------+--------------------------+
| **Unwanted Channel**                       | C/I                      |
+--------------------------------------------+--------------------------+
| Co-channel ^i^                             | 20 dB                    |
+--------------------------------------------+--------------------------+
|                                            |                          |
+--------------------------------------------+--------------------------+
| First Adjacent Channel ^ii^                | 6 dB                     |
+--------------------------------------------+--------------------------+
| ^I^ where the desired signal is based on   |                          |
| field strength levels at 50% of all        |                          |
| locations for 50% of the time              |                          |
|                                            |                          |
| ^ii^ where the undesired signal is based   |                          |
| on a field strength levels at 50% of their |                          |
| locations for 10% of the time              |                          |
+--------------------------------------------+--------------------------+

## Broadcasting-Satellite Service

The Broadcasting-Satellite Service (BSS) broadcasts radio or television
programming from earth orbiting satellites either directly to individual
consumer households or to community antenna television (CATV) feeds.
Currently there are BSS allocations between 30 MHz and 30 GHz serving
the United States and Possessions in the following bands:[^81]

> 2310‑2360 MHz[^82]
>
> 2500‑2690 MHz[^83]
>
> 12.2‑12.7 GHz
>
> 17.3‑17.7 GHz[^84]

The IPC for the BSS are typically expressed as wanted-to-unwanted signal
power ratios (C/I) at the receiver input. The majority of these IPC are
intended to protect against long-term interfering signals. Short-term
IPC allow higher interfering signal levels, but for only a limited
percentage of time. Some of these short-term IPC also limit the maximum
amount by which the threshold may be exceeded so that the degradation
may not actually result in a loss of service (outage) under otherwise
ideal conditions. The IPC can also be expressed as a power flux density
(pfd) within the BSS service area. In most of these cases the pfd is
determined from C/I criteria, thus, C/I is the primary IPC listed in
this section.

One form of BSS IPC is expressed as overall C/I. The overall C/I value
is the ratio of the wanted carrier power to the sum of all interfering
signals in a given channel including both the feeder up links and
service down links. This is depicted in equation (6-1).

  ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- --------
  $$\left( \frac{C}{I} \right)_{\text{Overall}} = \left( \left( \frac{C}{I} \right)_{\text{Up}}^{- 1} + \left( \frac{C}{I} \right)_{\text{Down}}^{- 1} \right)^{- 1}$$   (6‑1)

  ---------------------------------------------------------------------------------------------------------------------------------------------------------------------- --------

Where (C/I)~overall~, (C/I)~up~, and (C/I)~down~ are numerical (not
decibel) carrier to interfering signal power ratios for the overall
end-to-end link, the up link, and down link, respectively.

IPC for the BSS are expressed for adjacent channel as well as co-channel
interfering signals. Co-channel IPC have no carrier frequency offset,
which is defined as the difference between the unmodulated carrier
frequencies of the unwanted and wanted signals if the same type of
modulator is used in both channels. Adjacent-channel IPC are determined
through a series of measurements made with frequencies of the unwanted
signal varying approximately ±30 MHz from the wanted signal. Rec. ITU-R
BO.1293 gives instructions on how to create adjacent channel interfering
signal masks for protection of the BSS.[^85]

IPC for video signals are determined through subjective means as
described in Rec. ITU-R BO.600.[^86] The only noise that should be
present on the picture when assessing protection ratios is the receiver
thermal noise. The protection ratios are determined based on pictures
having a signal-to-unweighted-noise ratio of not less than 36 dB, in
order that system performance should not be limited by possible masking
of interfering signals by noise.

The IPC for sound transmissions are determined through measurement by
means of an objective method. Noise is measured after demodulation in
order to obtain the condition that the signal-to-weighted-noise ratio
within the sound channel does not exceed a specified value.[^87] Table I
of ITU-R BO.634-4 lists the parameters influencing the protection ratio
for sound signal together with a suggested reference case to establish a
common set of test conditions for measurements made by different
administrations.[^88] ex-CCIR Report 796 specifies a measurement method
for determination of IPC for sound.[^89]

The majority of IPC for BSS are defined for protecting analog signals.
However, in the United States, BSS is implemented using digital
techniques.

The IPC for the BSS are primarily found in the Radio Regulations (RR)
and ITU-R Recommendations of the BO Series. The following sections
describe the IPC by source. Key factors that influence the establishment
of IPC values, including interfering signal type, allocation status of
the interferer, and duration of the interfering signals, are also
provided when available.

### Appendix 30 (AP30) of the ITU Radio Regulations[^90]

Annex 3 of AP30 shows the IPC applicable for protecting the BSS from all
types of terrestrial interfering signals.[^91] Figure 6-1 depicts the
IPC and shows that there is a carrier frequency offset dependence for
all terrestrial interfering signals except from amplitude modulated
multi-channel television systems, in which case the IPC is a constant
C/I = 35 dB. For all cases, the IPC are only applied when the necessary
bandwidth of the terrestrial station overlaps the necessary bandwidth of
the BSS assignment.

![](media/image3.wmf){width="4.8125in" height="2.7083333333333335in"}

Figure 6‑1. Protection Ratio for BSS against a single entry terrestrial
service\
(except AM multi-channel TV systems)

In Section 3.4 of Annex 5 of AP30, the following aggregate IPC specify
C/I values for protection of analog and digital assignments from analog
television signals: 24 dB (co-channel), 16 dB (adjacent channel). The
following IPC specify C/I values for protection of digital assignments
from digital emissions: 21 dB (co-channel) 16 dB (adjacent channel).

For protection of FM-TV from other FM-TV transmissions, Figure 6-2 shows
an IPC template of C/I values as a function of carrier frequency offset.

![](media/image4.wmf){width="4.8125in" height="2.7083333333333335in"}

Figure 6‑2. Protection Ratio template (FMTV/FMTV),\
for planning of BSS systems in Region 2

Section 3 of Annex 1 of AP30 includes a section on IPC protecting the
BSS in Regions 1 and 2 in the band 12.2-12.5 GHz and in Region 3 in the
band 12.5-12.7 GHz from other proposed like assignments.[^92] These IPC
are intended to protect assignments in Regions 1 and 3 from proposals in
Region 2, and vice versa.

Annex 6 of AP30 provides protection requirements for sharing between
services in the 12 GHz band. The IPC are provided as C/I with the
stipulation that interfering signal levels shall not be exceeded for 99%
of the worst month. The C/I values for BSS protect TV/FM signals from
TV/FM signals of the BSS, FSS, FS, and BS. The C/I values listed are 30
dB for aggregate interfering signals, and 35 dB for single-entry
interfering signals. Figure 6-3 shows how much these values are reduced
as a function of carrier frequency offset.

![](media/image5.wmf){width="4.8125in" height="2.7083333333333335in"}

Figure 6‑3. Reference case protection ratios relative to co-channel
values

### Recommendation ITU-R BO.1297[^93]

This Recommendation suggests that the IPC in RR AP30 and AP30A for BSS
and associated feeder links were inadequate due to technological
improvements made in the BSS. It proposes the IPC shown in Table 6-13.
All IPC are specified as C/I where I represents the aggregate
interfering signal. The IPC for the overall path are based on equation
(6-1).

Table 6‑13

Aggregate Protection Ratios for Planning Revision of RR AP30 and AP30A\
in Regions 1 and 3

  ----------------------- ----------------------- -----------------------
                          Co-channel Protection   Adjacent Channel
                          Criteria                Protection Criteria

  Feeder link path        C/I ≥ 30 dB             C/I ≥ 22 dB

  Down link path          C/I ≥ 24 dB             C/I ≥ 16 dB

  Overall path            C/I ≥ 23 dB             C/I ≥ 15 dB
  ----------------------- ----------------------- -----------------------

### Recommendation ITU-R BO.1444[^94]

This Recommendation provides guidance for protecting the 12 GHz BSS and
associated 17 GHz feeder links from the earth and space station
emissions of all non-GSO (NGSO) FSS satellite networks operating in the
same frequency band. It states that these NGSO FSS emissions may be
responsible for at most 10% of the time allowance(s) for unavailability
of the given C/N value(s) as specified in the performance objectives of
the desired network, where N is the total noise level in the noise
bandwidth associated with the wanted carrier including all other
non‑time‑varying interfering signals. This seems to indicate that NGSO
FSS can exceed a C/(N+I) which is equal to the required BSS C/N
(including margins) for 10% of the permitted outage, where I only
includes the aggregate of NGSO FSS emissions. This is less strict than
requiring that I include other unwanted NGSO FSS networks.

The Recommendation also indicates that at no time should interfering
signals lead to a loss of video picture continuity in the desired
digital GSO BSS and associated feeder‑link network under clear-sky
conditions. Loss of video picture continuity includes error concealment
mechanisms such as "freeze frame" (repeat last frame), blank (black)
frame, or other techniques. The clear sky link margins above these video
picture continuity thresholds must also be specified. If none are
indicated, 1.5 dB is assumed. ITU-R BO.1444 also points out that the
impact of interfering signals on degradation is dependent on rain.
Specifically, rain increases system noise temperature and attenuates the
interfering and desired signals.

### FCC Report and Order 00-418[^95]

Pursuant to this document, Section 101.105 of CFR Title 47 allows MVDDS
transmitters to increase Direct Broadcast Satellite (DBS) outage at 12
GHz by up to 2.86% or up to 10 minutes per month.[^96] Certain DBS
providers have proposed that the 10% additional outage applied to the
aggregate from all other competing uses of the 12 GHz band, whereas the
2.86% additional outage applied to any one provider (e.g. MVDDS).[^97]
Included in that document is a section (Appendix H) that proposes a
method for converting percentage of unavailable time into a C/I value.

### Mitre Technical Report[^98] 

The Mitre Corporation was hired by the FCC to study the DBS and MVDDS
compatibility issue.[^99] Among other things, the report created a rain
attenuation model and used it to determine minimum C/I criteria for
various U.S. cities as a function of percentage increase of
unavailability of a particular DBS satellite. Table 6-14 represents the
case where MVDDS increases DBS unavailability by 10%. These values are
based on equation (6-2) below, where the effects of MVDDS are included
in an effective rain margin, A~eRm~. For their study, Mitre assumed that
the interfering signal was not attenuated during a DBS rain event.[^100]

Table 6‑14

Minimum C/I to Satisfy 10% Additional Link Outage (MVDDS interfering
with DBS)

+-----------------------------------+-----------------------------------+
| Location                          | Minimum C/I                       |
|                                   |                                   |
|                                   | **(dB)**                          |
+-----------------------------------+-----------------------------------+
| Boston, MA                        | 23.8                              |
+-----------------------------------+-----------------------------------+
| Chicago, IL                       | 23.7                              |
+-----------------------------------+-----------------------------------+
| Denver, CO                        | 27.3                              |
+-----------------------------------+-----------------------------------+
| Fargo, ND                         | 25.7                              |
+-----------------------------------+-----------------------------------+
| Houston, TX                       | 22.4                              |
+-----------------------------------+-----------------------------------+
| Los Angeles, CA                   | 22.1                              |
+-----------------------------------+-----------------------------------+
| Miami, FL                         | 21.9                              |
+-----------------------------------+-----------------------------------+
| Phoenix, AZ                       | 21.6                              |
+-----------------------------------+-----------------------------------+
| Seattle, WA                       | 25.5                              |
+-----------------------------------+-----------------------------------+
| Washington, D.C.                  | 22.9                              |
+-----------------------------------+-----------------------------------+

  --------------------------------------------------------------------------------------------------------------------------- --------
  $$\left( \frac{C}{I} \right)_{\text{required}} = \left( \frac{C}{I} \right)_{\text{rainy}\ \text{sky}} + A_{\text{eRm}}$$   (6‑2)

  --------------------------------------------------------------------------------------------------------------------------- --------

In Equation (6-2), (C/I)~required~ is the minimum acceptable
single-entry clear-sky IPC, (C/I)~rainy\ sky~ are the IPC in the
presence of rain without considering the effects of MVDDS, and A~eRm~ is
the effective rain margin plus another margin to account for the
increased aggregate due to the presence of MVDDS.[^101]

### Spectrum XXI

Spectrum XXI is a program intended for use by all government agencies to
aid in submitting systems for spectrum authorization by NTIA. Included
in the program is an IPC table to aid in interference analyses. To
protect broadcasting systems Spectrum XXI recommends the use of I/N =
--10 dB. This IPC is believed to be a conservative value intended for an
initial test for harmful interference. If a potential interference
source passes this test, compatibility is assumed without any further
analyses.

### Further Study

More work must be done to determine appropriate IPC involving digital
signals. ITU-R Report 634-4 suggests the test matrix given in Table
6-15:

Table 6‑15

Wanted and Unwanted Signal Interactions Requiring Further Study

  ----------------------------------- -----------------------------------
  Wanted Signal                       Unwanted Signal

  Digital                             Digital

  Digital                             FM

  FM                                  Digital

  Digital                             AM-VSB[^102]

  AM-VSB                              Digital
  ----------------------------------- -----------------------------------

Rec. ITU-R BO.600 provides a basis for further studies needed to define
more precisely the test conditions and procedures for developing BSS IPC
for digital modulation. More study is also needed to determine IPC for
protection of digital BSS signals from pulsed interfering signals due to
planned adjacent band reallocation at 17 GHz.

## SUMMARY

Table 6-16 contains a summary of IPC for the BS and BSS.

+-----------+--------+-----+-------+-------+---+--------+-----------+
| Servic    | Fre    | Int |       | Refe  | \ | Source | Comments  |
| e/Systems | quency | erf |       | rence | % | Do     |           |
|           | Bands  | ere |       | Band  | T | cument |           |
|           |        | nce |       | width | i |        |           |
|           |        | P   |       |       | m |        |           |
|           |        | rot |       |       | e |        |           |
|           |        | ect |       |       |   |        |           |
|           |        | ion |       |       |   |        |           |
+===========+========+=====+=======+=======+===+========+===========+
|           |        | CW  | P     |       |   |        |           |
|           |        | and | ulse/ |       |   |        |           |
|           |        | No  |       |       |   |        |           |
|           |        | ise | Other |       |   |        |           |
|           |        |     | ^i^   |       |   |        |           |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (ATSC) | 54-794 | N/S | C/I ≥ | N/S   | \ | Rec.   | I         |
|           | MHz    |     | 15 dB |       | > | ITU-R  | nterferer |
|           |        |     |       |       | 5 | B      | is ATSC   |
|           |        |     |       |       | 0 | T.1368 |           |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (ATSC) | 54-794 | N/S | C/I ≥ | N/S   | \ | Rec.   | I         |
|           | MHz    |     | 19 dB |       | > | ITU-R  | nterferer |
|           |        |     |       |       | 5 | B      | is ATSC,  |
|           |        |     |       |       | 0 | T.1368 | based on  |
|           |        |     |       |       |   |        | I/N ≥ 0dB |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (ATSC) | 54-794 | N/S | C/I ≥ | N/S   | \ | Rec.   | I         |
|           | MHz    |     | 2 dB  |       | > | ITU-R  | nterferer |
|           |        |     |       |       | 5 | B      | is NTSC   |
|           |        |     |       |       | 0 | T.1368 |           |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (ATSC) | 54-794 | N/S | C/I ≥ | N/S   | \ | Rec.   | I         |
|           | MHz    |     | 7 dB  |       | > | ITU-R  | nterferer |
|           |        |     |       |       | 5 | B      | is NTSC,  |
|           |        |     |       |       | 0 | T.1368 | based on  |
|           |        |     |       |       |   |        | comb      |
|           |        |     |       |       |   |        | filter    |
|           |        |     |       |       |   |        | and C/N = |
|           |        |     |       |       |   |        |           |
|           |        |     |       |       |   |        | 19 dB     |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (NTSC  | 54-794 | N/S | C/I ≥ | N/S   |   | Rec.   | I         |
| vision)   | MHz    |     | 34 dB |       |   | ITU-R  | nterferer |
|           |        |     |       |       |   | B      | is ATSC   |
|           |        |     |       |       |   | T.1368 |           |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (NTSC) | 54-794 | N/S | C/I ≥ | N/S   | 1 | Rec.   | I         |
|           | MHz    |     | 45 dB |       | - | ITU-R  | nterferer |
|           |        |     |       |       | 1 | BT.655 | is analog |
|           |        |     |       |       | 0 |        | vision    |
|           |        |     |       |       |   |        | and sound |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (NTSC) | 54-794 | N/S | C/I ≥ | N/S   | \ | Rec.   | I         |
|           | MHz    |     | 55 dB |       | > | ITU-R  | nterferer |
|           |        |     |       |       | 5 | BT.655 | is analog |
|           |        |     |       |       | 0 |        | vision    |
|           |        |     |       |       |   |        | and sound |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (TV FM | 54-794 | C/I | C/I ≥ | N/S   | 1 | Rec.   | I         |
| sound)    | MHz    | ≥   | 32 dB |       | - | ITU-R  | nterferer |
|           |        | 32  |       |       | 1 | BT.655 | is CW or  |
|           |        | dB  |       |       | 0 |        | FM sound  |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (TV FM | 54-794 | C/I | C/I ≥ | N/S   | \ | Rec.   | I         |
| sound)    | MHz    | ≥   | 39 dB |       | > | ITU-R  | nterferer |
|           |        | 39  |       |       | 5 | BT.655 | is CW or  |
|           |        | dB  |       |       | 0 |        | FM sound  |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (TV    | 54-794 | N/S | D/U ≥ | N/S   | N | Part   | I         |
| channel   | MHz    |     | 39 dB |       | / | 73.525 | nterferer |
| 6)        |        |     |       |       | S |        | is FM     |
|           |        |     |       |       |   |        | radio     |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS        | 54-794 | N/S | D/U ≥ | N/S   | N | Part   | I         |
| (analog   | MHz    |     | 34 dB |       | / | 73.623 | nterferer |
| TV)       |        |     |       |       | S |        | is DTV    |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (DTV)  | 54-794 | N/S | D/U ≥ | N/S   | N | Part   | I         |
|           | MHz    |     | 2 dB  |       | / | 73.623 | nterferer |
|           |        |     |       |       | S |        | is analog |
|           |        |     |       |       |   |        | TV        |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (DTV)  | 54-794 | N/S | D/U ≥ | N/S   | N | Part   | I         |
|           | MHz    |     | 15 dB |       | / | 73.623 | nterferer |
|           |        |     |       |       | S |        | is DTV    |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (NTSC) | 7      | N/S | D/U ≥ | N/S   | N | Part   | I         |
|           | 64-776 |     | 40 dB |       | / | 90.545 | nterferer |
|           | MHz    |     |       |       | S |        | is public |
|           |        |     |       |       |   |        | safety,   |
|           | 7      |     |       |       |   |        | based on  |
|           | 94-806 |     |       |       |   |        | Grade B   |
|           | MHz    |     |       |       |   |        | contour   |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS (DTV)  | 7      | N/S | D/U ≥ | N/S   | N | Part   | I         |
|           | 64-776 |     | 17 dB |       | / | 90.545 | nterferer |
|           | MHz    |     |       |       | S |        | is public |
|           |        |     |       |       |   |        | safety,   |
|           | 7      |     |       |       |   |        | based on  |
|           | 94-806 |     |       |       |   |        | Grade B   |
|           | MHz    |     |       |       |   |        | contour   |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS        | 88-108 | N/S | C/I ≥ | N/S   | N | Rec.   | I         |
| (stereo   | MHz    |     | 45 dB |       | / | ITU-R  | nterferer |
| FM radio) |        |     |       |       | S | BS.412 | is BS     |
|           |        |     |       |       |   |        | (stereo   |
|           |        |     |       |       |   |        | FM),      |
|           |        |     |       |       |   |        | long-term |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BS        | 88-108 | N/S | C/I ≥ | N/S   | N | Rec.   | I         |
| (stereo   | MHz    |     | 37 dB |       | / | ITU-R  | nterferer |
| FM radio) |        |     |       |       | S | BS.412 | is BS     |
|           |        |     |       |       |   |        | (stereo   |
|           |        |     |       |       |   |        | FM),      |
|           |        |     |       |       |   |        | s         |
|           |        |     |       |       |   |        | hort-term |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS earth | 11.    | N/S | C/I ≥ | N/S   | N | A      | Based on  |
| station   | 7-12.5 |     | 21 dB |       | / | rticle | WRC 2000  |
|           | GHz    |     |       |       | S | 11,    |           |
|           |        |     |       |       |   | A      |           |
|           |        |     |       |       |   | P30-61 |           |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS earth | 12.2‑1 | C/I | N/S   | N/S   | N | Annex  | Applies   |
| station   | 2.7GHz | ≥   |       |       | / | 3,     | to single |
|           | (      | 35  |       |       | S | A      | entry     |
|           | Region | dB  |       |       |   | P30-88 | te        |
|           | 2)     |     |       |       |   |        | rrestrial |
|           |        |     |       |       |   |        | in        |
|           |        |     |       |       |   |        | terferers |
|           |        |     |       |       |   |        | whose     |
|           |        |     |       |       |   |        | carrier   |
|           |        |     |       |       |   |        | frequency |
|           |        |     |       |       |   |        | is within |
|           |        |     |       |       |   |        | 10 MHz of |
|           |        |     |       |       |   |        | BSS       |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS earth | Any    | N/S | C/I ≥ | N/S   | N | AP     | I         |
| station   |        |     | 24 dB |       | / | 30-109 | nterferer |
| (analog   |        |     |       |       | S |        | is        |
| and       |        |     |       |       |   |        | aggregate |
| digital)  |        |     |       |       |   |        | from      |
|           |        |     |       |       |   |        | analog    |
|           |        |     |       |       |   |        | BSS       |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS earth | All    | N/S | C/I ≥ | N/S   | N | AP     | I         |
| station   | Bands  |     | 21 dB |       | / | 30-110 | nterferer |
| (digital) |        |     |       |       | S |        | is        |
|           |        |     |       |       |   |        | digital   |
|           |        |     |       |       |   |        | BSS       |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS earth | All    | N/S | C/I ≥ | N/S   | N | AP     | I         |
| station   | Bands  |     | 28 dB |       | / | 30-111 | nterferer |
| (FM/TV)   |        |     |       |       | S |        | is BSS    |
|           |        |     |       |       |   |        | FM/TV     |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS space | 17.    | N/S | I/N ≥ | N/S   | N | AP3    | I         |
| station   | 3-18.1 |     | --14  |       | / | 0A-128 | nterferer |
|           | GHz    |     | dB    |       | S |        | is FSS or |
|           |        |     |       |       |   |        | BSS space |
|           |        |     |       |       |   |        | station   |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS space | 17.    | N/S | I/N ≥ | N/S   | N | AP3    | I         |
| station   | 8-18.1 |     | -     |       | / | 0A-128 | nterferer |
|           | GHz    |     | -15.2 |       | S |        | is FSS    |
|           |        |     | dB    |       |   |        | earth     |
|           |        |     |       |       |   |        | station   |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS TV/FM | 12 GHz | N/S | C/I ≥ | N/S   | N | AP     | I         |
|           |        |     | 30    |       | / | 30-131 | nterferer |
|           |        |     | dB\   |       | S |        | is fixed  |
|           |        |     | aggr  |       |   |        | or        |
|           |        |     | egate |       |   |        | bro       |
|           |        |     |       |       |   |        | adcasting |
|           |        |     | C/I ≥ |       |   |        | TV/FM     |
|           |        |     | 35    |       |   |        |           |
|           |        |     | dB\   |       |   |        |           |
|           |        |     | si    |       |   |        |           |
|           |        |     | ngle- |       |   |        |           |
|           |        |     | entry |       |   |        |           |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS earth | 17.    | N/S | I/N ≥ | N/S   | N | ITU-R  | I         |
| stations  | 3‑17.8 |     | --18  |       | / | Doc    | nterferer |
|           | GHz    |     | dB    |       | S | 4‑9‑1  | is FSS    |
|           |        |     |       |       |   | 1/90‑E | earth     |
|           |        |     |       |       |   |        | station   |
|           |        |     |       |       |   |        | to NGSO   |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS       | All    | N/S | C/I ≥ | N/S   | N | Rec.   | I         |
| Feeder    | Bands  |     | 30 dB |       | / | ITU-R  | nterferer |
| Link      |        |     |       |       | S | B      | is BSS.   |
|           |        |     |       |       |   | O.1297 | This is   |
|           |        |     |       |       |   |        | an        |
|           |        |     |       |       |   |        | aggregate |
|           |        |     |       |       |   |        | IPC       |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| BSS earth | 12 GHz | N/S | C/I ≥ | N/S   | 1 | Mitre  | I         |
| stations  |        |     | 27.3  |       | 0 | Tec    | nterferer |
|           |        |     | dB    |       | % | hnical | is MVDDS  |
|           |        |     |       |       |   | Report | limited   |
|           |        |     |       |       |   |        | to 10% of |
|           |        |     |       |       |   |        | outage    |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| Bro       | All    | I/N | I/N ≤ | N/S   | N | Sp     | Con       |
| adcasting | Bands  | =   | ‑10   |       | / | ectrum | servative |
|           |        | ‑10 | dB    |       | S | XXI    | criterion |
|           |        | dB  |       |       |   |        | for a     |
|           |        |     |       |       |   |        | first     |
|           |        |     |       |       |   |        | level     |
|           |        |     |       |       |   |        | int       |
|           |        |     |       |       |   |        | erference |
|           |        |     |       |       |   |        | analysis. |
+-----------+--------+-----+-------+-------+---+--------+-----------+
| ^I^ Other |        |     |       |       |   |        |           |
| refers to |        |     |       |       |   |        |           |
| int       |        |     |       |       |   |        |           |
| erference |        |     |       |       |   |        |           |
| from BS   |        |     |       |       |   |        |           |
| and BSS   |        |     |       |       |   |        |           |
| system.   |        |     |       |       |   |        |           |
+-----------+--------+-----+-------+-------+---+--------+-----------+

**REFERENCES**

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#  MOBILE AND MOBILE SATELLITE SERVICEs 

## Introduction

Various station classes operate in the Mobile Service (MS) and the
Mobile Satellite Service (MSS) within the 30 MHz to 30 GHz frequency
range. The MS is further subdivided into the following services: land
mobile (LMS), maritime mobile (MMS), aeronautical mobile (AMS),
aeronautical mobile route (AM(R)S),[^103] and aeronautical mobile
off-route (AM(OR)S) services.[^104] The MSS includes the following
services: land mobile-satellite (LMSS), maritime mobile-satellite
(MMSS), aeronautical mobile-satellite (AMSS), aeronautical
mobile-satellite route (AMS(R)S), and aeronautical mobile-satellite
off-route (AMS(OR)S) services.

## Mobile Service

### Mobile Service in General

For the MS, the nature of the interfering signal source (i.e., CW,
noise, pulse, and impulse) was not always defined with the IPC in the
various reference sources. The IPC extracted from the references are for
co-channel operations unless otherwise stated. The percentages of time
and locations for which the IPC apply were not provided in most cases.

-   **NTIA Manual (Annex I)**

Annex I of the NTIA Manual describes a procedure to evaluate
interference in the 162-174 MHz and 406-420 MHz bands, both of which
have a primary allocation for the MS.[^105] Annex I provides receiver
sensitivity (desired signal power) values in the presence of low,
average, and high noise environments.[^106] These values are also
intended to represent interfering signal thresholds. Table 1 of Annex I
states that unacceptable interference may result if predicted received
interfering signal power levels exceeds this threshold for more than 10%
of the time at 50% of the locations.

-   **Spectrum XXI**

For digital mobile systems Spectrum XXI[^107] uses I/N = --6 dB for the
MS.[^108] This is based on allowing interfering signals to cause a 1 dB
increase in the receiver noise level. For analog mobile systems, an IPC
of I/N = 0 dB is specified.

-   **ITU Report**

CCIR Report 826 shows IPC for AM and FM voice systems and interfering
signals from direct sequence (DS) and frequency hopping (FH)[^109]
spread spectrum transmissions and similar interfering signal
sources.[^110] Characteristics of the desired signals analyzed are shown
in Table 7-1.

Table 7‑1

Characteristics of Mobile Systems Analyzed

  ----------------- ----------- ---------- ---------- ------------ ----------- ----------
  Modulation        Receiver IF Receiver   Receiver   Modulation   Peak        E.I.R.P.
  Type^i^           Bandwidth   Antenna    Noise      Index        Deviation   (dBm)
                    (kHz)       Gain (dBi) Figure                  (kHz)       
                                           (dB)                                

  A3E               8           3          6          1.0          N/S         50

  F3E               16          3          6          1.67         ±5          50

  ^i^ A3E indicates                                                            
  amplitude                                                                    
  modulated                                                                    
  double-sideband                                                              
  analog voice. F3E                                                            
  indicates                                                                    
  frequency                                                                    
  modulated analog                                                             
  voice.                                                                       
  ----------------- ----------- ---------- ---------- ------------ ----------- ----------

Table 7-2 provides the range of pulse widths and repetition rates over
which the measurements were taken to determine the IPC for FH
interfering signals. All IPC associated with this source are listed in
Table 7-3 according to two performance levels. The two performance
levels were taken to be articulation index (AI) values of 0.7 and 0.9,
where AI is a measure of voice intelligibility. The 0.7 AI threshold
value marks the point at which degradation to intelligibility begins to
appear, and the 0.9 value is the threshold between marginally commercial
and good commercial quality. The IPC stated are conservative values
insofar as they are the greatest S/I required to ensure an AI of at
least 0.7 or 0.9 for all values of pulse width, pulse repetition
frequency and off-tuning for which measurements had been performed.

Table 7‑2

Parameter Ranges for FHSS Interfering Signal Measurements

  -------------- -------------- -------------- -------------- --------------
  Modulation     Pulse Width                   Pulse          
  Type           (μs)                          Repetition     
                                               Frequency      
                                               (pps)          

                 From           To             From           To

  A3E            5              1000           10             400

  F3E            1              1000           40             1000
  -------------- -------------- -------------- -------------- --------------

Table 7‑3

IPC to Protect against Various Interfering Signal Types

+-----------+------------+----------+----------+-----------------------+
| M         | IPC for    |          |          | Comments              |
| odulation | In         |          |          |                       |
| Type      | terference |          |          |                       |
|           | Type^i^    |          |          |                       |
+===========+============+==========+==========+=======================+
|           | Same       | DSSS     | FHSS     |                       |
+-----------+------------+----------+----------+-----------------------+
| A3E       | S/I ≥ 7 dB | S/I ≥ 21 | S/I ≥ 19 | S/N ≥ 45 dB is        |
|           | for AI =   | dB for   | dB for   | assumed for the       |
|           | 0.7        | AI = 0.7 | AI = 0.7 | protected system.     |
+-----------+------------+----------+----------+-----------------------+
|           | S/I ≥ 13   | S/I ≥ 28 | S/I ≥ 31 |                       |
|           | dB for AI  | dB for   | dB for   |                       |
|           | = 0.9      | AI = 0.9 | AI = 0.9 |                       |
+-----------+------------+----------+----------+-----------------------+
| F3E       | S/I ≥ 6 dB | S/I ≥ 8  | S/I ≥ 19 | S/N ≥ 22 dB is        |
|           |            | dB for   | dB for   | assumed for the       |
|           | for AI =   | AI = 0.7 | AI = 0.7 | protected system.     |
|           | 0.7        |          |          |                       |
+-----------+------------+----------+----------+-----------------------+
|           | S/I ≥ 20   | S/I ≥ 15 | S/I ≥ 30 |                       |
|           | dB for AI  | dB for   | dB for   |                       |
|           | = 0.9      | AI = 0.9 | AI = 0.9 |                       |
+-----------+------------+----------+----------+-----------------------+
| ^i^ DSSS  |            |          |          |                       |
| is direct |            |          |          |                       |
| sequence  |            |          |          |                       |
| spread    |            |          |          |                       |
| spectrum, |            |          |          |                       |
| FHSS is   |            |          |          |                       |
| frequency |            |          |          |                       |
| hopping   |            |          |          |                       |
| spread    |            |          |          |                       |
| spectrum, |            |          |          |                       |
| "Same"    |            |          |          |                       |
| indicates |            |          |          |                       |
| that the  |            |          |          |                       |
| in        |            |          |          |                       |
| terfering |            |          |          |                       |
| signal    |            |          |          |                       |
| has the   |            |          |          |                       |
| same      |            |          |          |                       |
| m         |            |          |          |                       |
| odulation |            |          |          |                       |
| as the    |            |          |          |                       |
| desired   |            |          |          |                       |
| signal.   |            |          |          |                       |
+-----------+------------+----------+----------+-----------------------+

### Land Mobile Service 

The following subsections describe IPC for protection of the LMS.

#### Federal Government Standards {#federal-government-standards .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

-   **National Telecommunications and Information Administration**

Appendix D of NTIA Spectrum Reallocation Final Report listed indoor and
outdoor interfering signal thresholds at --117 and --119 dBm,
respectively for personal communications services (PCS) operating at
1850-1990 MHz.[^111] This assumed an allocation of 10% of the total
interference budget to external interfering signal sources. These
threshold values were extracted from Rec. ITU-R M.687.[^112]

NTIA Special Publication 01-46 "The Potential for Accommodating Third
Generation Mobile Systems in the 1710-1850 MHz Band" provides two IPC
thresholds for IMT-2000 Mobile and Base Stations that are listed in
Table 7-5, depending on the type of modulation and access
technique.[^113] For example, for mobile stations, an I value of -110
dBm for Code Division Multiple Access (CDMA) for a bandwidth of 1.25
MHz, and an I value of -131 dBm (Enhanced Data Rates for GSM Evolution
Edge) for a 0.03 MHz bandwidth for land mobile base stations. The
thresholds provided in the report were the most recent industry-approved
characteristics, but actual 3G systems may have different parameters.

NTIA TM 87-122 presents operational and performance characteristics of
radios equipped with the Data Encryption Standard.[^114] A portion of
the report describes a capture effect inherent in FM systems that causes
the wanted signal to reduce interference from the unwanted signal when
the received wanted signal is stronger than the unwanted signal by the
amount of the capture ratio. For the analog mode the capture ratio
varied from 2 dB at a high S/N to 5 dB at a low S/N. In the digital mode
the capture ratios ranged between 2 and 15 dB for high and low S/N
conditions respectively.

-   **Federal Communications Commission**

The following FCC Rules from Title 47 of the Code of Federal
Regulations, were investigated for potential IPC: Part 22 (Public Mobile
Services), Part 24 (Personal Communications Services), Part 27
(Miscellaneous Wireless Communications Services), Part 80 (Stations in
the Maritime Service) Part 90 (Private Land Mobile Radio Services), Part
95 (Personal Radio Services).

Section 90.187 of the Commission Rules discusses interference from
trunked systems to conventional VHF and UHF networks. A subsection
defines objectionable interference as occurring when the interfering
signal contour (19 dBμ for VHF, and 21 dBμ for UHF) of a proposed
trunked station would intersect the service contour (37 dBμ for VHF, and
39 dBμ for UHF) of an existing station. This is equivalent to a
protection ratio of 18 dB.

Section 80.773 of the Commission Rules states that a VHF public coastal
station that shares a frequency with an incumbent private land mobile
radio (PLMR), the coastal station must provide a 10 dB or greater
protection ratio with respect to the PLMR signal level.

#### Industry Association Standards {#industry-association-standards .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

**Telecommunications Industry Association (TIA)**

TIA TSB 88‑A provides a section called "Interference Prediction" which
states: "It is assumed that for any modulation combination, it is valid
to treat adjacent channel interference as additional noise power that
enters a receiver's IF filter".[^115] Interference between different
modulation types may be calculated based on the power spectrum of the
given transmitter modulation and the IF filter selectivity and IF C/N
for a specified channel performance criterion (CPC)[^116] in a Rayleigh
faded channel. The C/(I+N) then becomes a predictor of CPC." TIA TSB
88-A provides a list of various modulation types with associated IPC for
various delivered audio quality (DAQ)[^117] ratings and desired BER.
Portions of the contents of this table are listed in Table 7-5.

#### International Recommendations {#international-recommendations .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

**International Telecommunication Union**

Rec. ITU-R M.687-2 estimates the level of interfering signals in
IMT-2000 receivers that can be tolerated using a link power budget based
on personal mobile systems being interference limited, rather than noise
limited. As a basis for IPC, 10% of the total interference budget is
allocated to the external interfering signal sources. The IPC specify
maximum permissible aggregate interfering signal power levels that can
be received by personal stations without significantly degrading the
quality of service.

Rec. ITU-R M.1073 deals with LMS cellular communications in the bands at
800, 900, 1800, and 1900 MHz ranges.[^118] Section 4.4 indicates that a
co-channel protection ratio of C/I = 9 dB is permissible and
accommodates a possible cellular frequency reuse corresponding to a
9-cell cluster.

Rec. ITU-R M.1388 provides a coordination threshold level to protect a
digital system in the LMS, which is already operating in the 1452-1492
MHz band in one country from proposed space stations in the Broadcasting
Satellite Service.[^119] The threshold is --150 dB(W/m^2^) in 4 kHz
bandwidth for all angles of arrival and applies as a general protection
criterion for the LMS in that band until additional studies are
completed.

Annex 2 of Rec. ITU-R SM.851 provides IPC for protection of land mobile
services from the BS.[^120] The listed IPC protect only analog and some
digital voice land mobile systems from analog AM vestigial sideband
television and analog FM audio broadcasting signals. For television
signals, IPC are specified for land mobile channels that fall within 0.5
MHz of the vision carrier. For FM audio broadcasting signals, IPC are
listed as a function of frequency separation between carriers of the two
services. Rec. ITU-R SM. 851 also notes that since the IPC are based on
interfering signals using the same type of modulation as the wanted
signal, correction factors may be required before applying them to
sharing with the BS. The IPC from this source are listed in Table 7-5.

### Maritime Mobile Service

The following subsections list IPC for protection of MMS systems.

#### Federal Agencies {#federal-agencies .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

-   **National Telecommunications Information Administration**

NTIA Report 99-362 evaluates the performance of various 25 kHz marine
radios.[^121] Specifically, the objectives of this report were to:

> 1\) measure the SINAD of marine radios operating in a shipboard
> environment;
>
> 2\) identify the sources of interference and interference mechanisms;
> and
>
> 3\) investigate ways to mitigate and preclude the interference.

NTIA Report 00-376 investigates EMC between marine automatic
identification (AIS) and public correspondence (PC) systems in the
maritime mobile VHF band.[^122] Both closed system and radiated tests
were performed on PC and AIS operations for different frequency offsets.
The test results were given in terms of interference-to-signal (I/S)
power ratios for different test conditions and scenarios. Further
evaluation is required to determine if IPC can be developed from the
test results.

NTIA Report 00-343 assesses the compatibility between 25 and 12.5 kHz
channelized marine VHF radios.[^123] Specifically, the objectives of the
report were to:

1\) determine the susceptibility of various 12.5 kHz and 25 kHz radios
to adjacent/interstitial channel interference, and

2\) evaluate the interoperability of various 12.5 kHz and 25 kHz radios.

Both bench and radiated tests and results were conducted and results
were provided in terms of S/I values. Further evaluation is required to
determine if IPC can be developed from the test results.

NTIA Report 99-363 assesses various 25 kHz radios to determine
compliance with the performance standards for marine VHF radio receivers
contained in International Electrotechnical Commission (IEC) document
1097-7.[^124] Specifically, tests were performed to determine:
sensitivity, co-channel rejection ratio, adjacent channel selectivity,
intermodulation response, and blocking. Testing results are provided in
terms of I/S power ratios. Further evaluation is required to determine
if IPC can be developed from the test results.

-   **Federal Communications Commission**

Section 80.773 of the FCC Rules "Co-channel interference protection"
states "Where a VHF public coast station geographic area licensee shares
a frequency with an incumbent VHF public coast station licensee, the
ratio of desired to undesired signal strengths must be at least 12 dB
within the service area of the station." These IPC are listed in Table
7-5.

### Aeronautical Mobile Service

The following subsections describe IPC for protection of AMS systems.

#### International Recommendations {#international-recommendations-1 .Style-Style-Heading-4Heading-4-Char2-CharHeading-4-Char1-Char-CharH...1}

**International Civil Aviation Organization (ICAO)**

ICAO Annex 10, Volume V specifies provisions concerning the deployment
of VHF frequencies and avoidance of harmful interference.[^125] Section
4.1.5.1 indicates that points at the protection heights and at the limit
of the functional service range of each facility are separated by
distances not less than that required to provide a desired to undesired
signal power ratio of 14 dB. Attachment A to that section states that
the application of the 14 dB planning criteria assumes that it is highly
unlikely that two aircraft will be at the maximum edge of their
respective service volumes and at the closest point between these two
volumes.

## Mobile Satellite Service

For the MSS, the only sources of IPC are the ITU-R M series
Recommendations. For digital MSS carriers, the IPC are specified as
apportionment of the total noise. A summary of these Recommendations for
various types of systems is listed in Table 7-4.

Table 7‑4

List of ITU-M Recommendations Related to IPC for the MSS

  -------------------------------- ----------------- -----------------------
                                   ITU-R             
                                   Recommendations   

  System                           Performance       Interfering Signal
                                   Objective         Power Apportionment

  MMSS voice circuit               M.547[^126]       N/S

  MMSS telegraph                   M.552[^127]       N/S

  GSO/AMSS non-ISDN                M.1229[^128]      M.1183[^129]

  GSO/AMS(R)S                      M.1037[^130]      M.1234[^131]

  GSO/MSS ISDN                     M.1476[^132]      M.1183

  GSO/MSS non-ISDN                 M.1181[^133]      M.1183

  NGSO/MSS downlink                M.1230[^134]      M.1231[^135],
                                                     M.1232[^136]

  NGSO/MSS Cospas-SarSat uplink    M.1478[^137]      M.1478
  -------------------------------- ----------------- -----------------------

### Geostationary Satellite Service

From Rec. ITU-R M.1183, for a GSO/MSS digital channel in the 1-3 GHz
band, the permissible levels of interference caused by other GSO/MSS
systems and GSO/FSS systems should exceed the levels shown in Table 7-6
for no more than (100-x)% of any month. Here x is the percentage of time
availability as defined under the relevant ITU-R Recommendations on
performance objectives (Table 7-4). The total noise power is defined as
the noise power at the input of the demodulator, which gives rise to the
desired performance.

From Rec. ITU-R M.1234, for a GSO/AMS(R)S digital channel in the bands
1545 to 1555 MHz and 1646.5 to 1656.5 MHz, the permissible level of
interference caused by other AMS(R)S, AMSS, and FSS should not exceed:

-   for aggregate interfering signals, 20% of total noise power,

-   for single-entry interfering signals, 6% of total noise power.

Here the total noise power is defined as the noise power at the input to
the demodulator, which would give rise to the BER performance objective
specified in Rec. ITU-R M.1037.

### Nongeostationary Satellite Service - Downlink

From Rec. ITU-R M.1231, for FDMA and spread spectrum multiple access
(SSMA) NGSO/MSS downlinks in the 137-138 MHz band, the maximum aggregate
interfering signal level at the input of the receiving antenna is
specified in Table 7-6. The data are derived based on two sample systems
addressed in Rec. ITU-R M.1231.

From Rec. ITU-R M.1232, for FDMA or SSMA NGSO/MSS downlinks in the
137-138 MHz band, the maximum single-entry interfering signal level at
the input of the receiving antenna from a NGSO/MSS system or any non-MSS
system is specified in Table 7-6. These IPC are derived assuming two
interfering NGSO/MSS systems and one interfering terrestrial system.

### NGSO Satellite Service (Cospas-Sarsat Uplink)

From Rec. ITU-R M.1478, the protection criteria for Cospas-Sarsat
uplinks operating in the 406-406.1 MHz band are specified in terms of
interfering signal power flux density (pfd) or spectral pfd (spfd) at
the Cospas-Sarsat satellite receive antenna. These IPC are listed in
Table 7-6.

## Summary 

A summary of the IPC for the MS and MSS are provided in Tables 7-5 and
7-6 respectively.

+-------+-------+-------+-------+------+----+------+---------------+
| Sys   | Freq  | In    |       | R    | \% | So   | Comments      |
| tems/ | uency | terfe |       | efer | Ti | urce |               |
|       | Bands | rence |       | ence | me | Docu |               |
| Ser   |       | Prote |       | b    |    | ment |               |
| vices |       | ction |       | andw |    |      |               |
|       |       |       |       | idth |    |      |               |
+=======+=======+=======+=======+======+====+======+===============+
|       |       | CW/   | P     |      |    |      |               |
|       |       | Noise | ulse/ |      |    |      |               |
|       |       |       |       |      |    |      |               |
|       |       |       | Other |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| \`    |       |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| M     | 16    | I/N 0 | N/S   | IF   | 10 | NTIA | I/N of 0 dB   |
| obile | 2-174 | dB    |       | Pass |    | Ma   | should not be |
|       | and   |       |       | band |    | nual | exceeded at   |
|       |       |       |       |      |    | A    | more than 50% |
|       | 406.  |       |       |      |    | nnex | of locations  |
|       | 1-420 |       |       |      |    | I    |               |
|       | MHz   |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| M     | 30    | I/N ≤ | N/S   | IF   | N  | Spec | N/S           |
| obile | -1215 | --6   |       | Pass | /S | trum |               |
| (Dig  | MHz   | dB    |       | band |    | XXI  |               |
| ital) |       |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| M     | 30    | I/N ≤ | N/S   | IF   | N  | Spec | N/S           |
| obile | -1215 | 0 dB  |       | Pass | /S | trum |               |
| (An   | MHz   |       |       | band |    | XXI  |               |
| alog) |       |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| M     | All   | S/I ≥ | S/I ≥ | N/S  | N  | CCIR | Assumes S/N ≥ |
| obile |       | 21 dB | 19 dB |      | /S | Re   | 45 dB. IPC    |
|       |       |       | (AI = |      |    | port | for           |
| (AM   |       | (AI = | 0.7)  |      |    |      | "pulse/other" |
| Do    |       | 0.7)  |       |      |    | 826  | are for pulse |
| uble- |       |       |       |      |    |      | interfering   |
|       |       |       |       |      |    |      | signals.      |
| Sid   |       |       |       |      |    |      |               |
| eband |       |       |       |      |    |      |               |
| V     |       |       |       |      |    |      |               |
| oice) |       |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | S/I ≥ | S/I ≥ |      |    |      |               |
|       |       | 28 dB | 31 dB |      |    |      |               |
|       |       |       | (AI = |      |    |      |               |
|       |       | (AI = | 0.9)  |      |    |      |               |
|       |       | 0.9)  |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | N/S   | S/I ≥ | N/S  | N  |      | Assumes S/N ≥ |
|       |       |       | 7 dB  |      | /S |      | 45 dB. IPC    |
|       |       |       | (AI = |      |    |      | for           |
|       |       |       | 0.7)  |      |    |      | "pulse/other" |
|       |       |       |       |      |    |      | are for A3E   |
|       |       |       |       |      |    |      | interfering   |
|       |       |       |       |      |    |      | signals.      |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       |       | S/I ≥ |      |    |      |               |
|       |       |       | 13 dB |      |    |      |               |
|       |       |       | (AI = |      |    |      |               |
|       |       |       | 0.9)  |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| M     | All   | S/I ≥ | S/I ≥ | N/S  | N  | CCIR | Assumes S/N ≥ |
| obile |       | 8 dB  | 19 dB |      | /S |      | 22 dB. IPC    |
|       |       |       | (AI = |      |    | Re   | for           |
| (FM   |       | (AI   | 0.7)  |      |    | port | "pulse/other" |
| V     |       | =0.7) |       |      |    |      | are for pulse |
| oice) |       |       |       |      |    | 826  | interfering   |
|       |       |       |       |      |    |      | signals.      |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | S/I ≥ | S/I ≥ |      |    |      |               |
|       |       | 15 dB | 30 dB |      |    |      |               |
|       |       |       |       |      |    |      |               |
|       |       | (AI = | (AI = |      |    |      |               |
|       |       | 0.9)  | 0.9)  |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | N/S   | S/I ≥ | N/S  | N  |      | Assumes S/N ≥ |
|       |       |       | 6 dB  |      | /S |      | 22 dB. IPC    |
|       |       |       | (AI = |      |    |      | for           |
|       |       |       | 0.7)  |      |    |      | "pulse/other" |
|       |       |       |       |      |    |      | are for F3E   |
|       |       |       |       |      |    |      | interfering   |
|       |       |       |       |      |    |      | signal.       |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       |       | S/I ≥ |      |    |      |               |
|       |       |       | 20 dB |      |    |      |               |
|       |       |       |       |      |    |      |               |
|       |       |       | (AI = |      |    |      |               |
|       |       |       | 0.9)  |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+

+-------+-------+-------+-------+------+----+------+---------------+
|       |       | CW/   | P     |      |    |      |               |
|       |       | Noise | ulse/ |      |    |      |               |
|       |       |       |       |      |    |      |               |
|       |       |       | Other |      |    |      |               |
+=======+=======+=======+=======+======+====+======+===============+
| Land  | Below | I ≤   | N/S   | N/S  | N  | Rec. | Maximum       |
| M     | 3 GHz | --117 |       |      | /S | I    | permissible   |
| obile |       | dBm   |       |      |    | TU-R | aggregate     |
|       |       | (In   |       |      |    | M    | interfering   |
| (IMT  |       | door) |       |      |    | .687 | signal power  |
| -2000 |       |       |       |      |    | and  | levels that   |
| and   |       |       |       |      |    |      | can be        |
| PCS   |       |       |       |      |    | NTIA | received      |
| per   |       |       |       |      |    | Spe  | without       |
| sonal |       |       |       |      |    | cial | significantly |
| stat  |       |       |       |      |    | Pub  | degrading the |
| ions) |       |       |       |      |    | lica | quality of    |
|       |       |       |       |      |    | tion | service.      |
|       |       |       |       |      |    |      |               |
|       |       |       |       |      |    | 9    |               |
|       |       |       |       |      |    | 5-32 |               |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | I ≤   |       |      |    |      |               |
|       |       | --119 |       |      |    |      |               |
|       |       | dBm   |       |      |    |      |               |
|       |       | (Out  |       |      |    |      |               |
|       |       | door) |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| Land  | Below | I ≤   | N/S   | 1.25 | N  | NTIA | Desired       |
| M     | 3 GHz | --110 |       | MHz  | /S | Spe  | signal at     |
| obile |       | dBm   |       |      |    | cial | sensitivity   |
|       |       | (CDMA |       |      |    | Pub  | level,        |
| (IMT  |       | 2000  |       |      |    | lica |               |
| 2000  |       | 1X)   |       |      |    | tion | I/N ≤ --6 dB  |
| M     |       |       |       |      |    |      |               |
| obile |       |       |       |      |    | 0    |               |
| Stat  |       |       |       |      |    | 1-46 |               |
| ions) |       |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | I ≤   | N/S   | 3.75 |    |      |               |
|       |       | --105 |       | MHz  |    |      |               |
|       |       | dBm   |       |      |    |      |               |
|       |       | (CDMA |       |      |    |      |               |
|       |       | 2000  |       |      |    |      |               |
|       |       | 3X)   |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | I ≤   | N/S   | 3.84 |    |      |               |
|       |       | --111 |       | MHz  |    |      |               |
|       |       | dBm   |       |      |    |      |               |
|       |       | (TD-  |       |      |    |      |               |
|       |       | CDMA) |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | I ≤   | N/S   | N/S  |    |      |               |
|       |       | --105 |       |      |    |      |               |
|       |       | dBm   |       |      |    |      |               |
|       |       |       |       |      |    |      |               |
|       |       | (W-   |       |      |    |      |               |
|       |       | CDMA) |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+

+-------+-------+-------+-------+------+---+------+---------------+
| Sys   | Freq  | **In  |       | R    | \ | So   | Comments      |
| tems/ | uency | terfe |       | efer | % | urce |               |
|       | Bands | rence |       | ence | T | Docu |               |
| Ser   |       | Pr    |       | b    | i | ment |               |
| vices |       | otect |       | andw | m |      |               |
|       |       | ion** |       | idth | e |      |               |
+=======+=======+=======+=======+======+===+======+===============+
|       |       | CW/   | P     |      |   |      |               |
|       |       | Noise | ulse/ |      |   |      |               |
|       |       |       |       |      |   |      |               |
|       |       |       | Other |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| Land  | Below | I ≤   | N/S   | 1.25 | N | NTIA | Desired       |
| M     | 3 GHz | --94  |       | MHz  | / | Spe  | signal 10 dB  |
| obile |       | dBm   |       |      | S | cial | above         |
|       |       |       |       |      |   | Pub  | sensitivity   |
| (IMT  |       | (CDMA |       |      |   | lica | level         |
| 2000  |       | 2000  |       |      |   | tion |               |
| M     |       | 1X)   |       |      |   | 0    |               |
| obile |       |       |       |      |   | 1-46 |               |
| Stat  |       |       |       |      |   |      |               |
| ions) |       |       |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 3.75 | N |      |               |
|       |       | --90  |       | MHz  | / |      |               |
|       |       | dBm   |       |      | S |      |               |
|       |       |       |       |      |   |      |               |
|       |       | (CDMA |       |      |   |      |               |
|       |       | 2000  |       |      |   |      |               |
|       |       | 3X)   |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 3.84 |   |      |               |
|       |       | --92  |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       |       |       |      |   |      |               |
|       |       | (TD-  |       |      |   |      |               |
|       |       | CDMA) |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | N/S  |   |      |               |
|       |       | --89  |       |      |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       | (W-   |       |      |   |      |               |
|       |       | CDMA) |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| Land  | Below | I ≤   | N/S   | 1.25 | N | NTIA | Desired       |
| M     | 3 GHz | --114 |       | MHz  | / | Spe  | signal at     |
| obile |       | dBm   |       |      | S | cial | sensitivity   |
|       |       |       |       |      |   | Pub  | level,        |
| (IMT  |       | (CDMA |       |      |   | lica |               |
| 2000  |       |       |       |      |   | tion | I/N ≤ --6 dB  |
| Base  |       | 2000  |       |      |   | 01   |               |
| Stat  |       | 1X)   |       |      |   | -46. |               |
| ions) |       |       |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 3.75 |   |      |               |
|       |       | --109 |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       | (CDMA |       |      |   |      |               |
|       |       | 2000  |       |      |   |      |               |
|       |       | 3X)   |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 0.03 |   |      |               |
|       |       | --131 |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       | (UWC) |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 0.22 |   |      |               |
|       |       | --123 |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       | (U    |       |      |   |      |               |
|       |       | WC)\* |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 3.84 |   |      |               |
|       |       | --115 |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       | (TD-  |       |      |   |      |               |
|       |       | CDMA) |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| Land  | Below | I ≤   | N/S   | 1.25 | N | NTIA | Desired       |
| M     | 3 GHz | --98  |       | MHz  | / | Spe  | signal 10 dB  |
| obile |       | dBm   |       |      | S | cial | above         |
|       |       |       |       |      |   | Pub  | sensitivity   |
| (IMT  |       | (CDMA |       |      |   | lica | level         |
| 2000  |       | 2000  |       |      |   | tion |               |
| Base  |       | 1X)   |       |      |   | 01   |               |
| Stat  |       |       |       |      |   | -46. |               |
| ions) |       |       |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 3.75 |   |      |               |
|       |       | --93  |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       | (CDMA |       |      |   |      |               |
|       |       | 2000  |       |      |   |      |               |
|       |       | 3X)   |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 0.0  |   |      |               |
|       |       | --115 |       | 3MHz |   |      |               |
|       |       | dBm\  |       |      |   |      |               |
|       |       | (UWC) |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 0.22 |   |      |               |
|       |       | --107 |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       | (UWC) |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | I ≤   | N/S   | 3.84 |   |      |               |
|       |       | --96  |       | MHz  |   |      |               |
|       |       | dBm   |       |      |   |      |               |
|       |       |       |       |      |   |      |               |
|       |       | (TD-  |       |      |   |      |               |
|       |       | CDMA) |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| Land  | N/S   | S/I ≥ | N/S   | N/S  | N | NTIA | high S/N      |
| M     |       | 2 dB  |       |      | / | TM   |               |
| obile |       | (A)   |       |      | S |      |               |
|       |       | S/I = |       |      |   | 87   |               |
|       |       | 4 dB  |       |      |   | -122 |               |
|       |       | (D)   |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
|       |       | S/I ≥ | N/S   | N/S  | N |      | low S/N       |
|       |       | 5 dB  |       |      | / |      |               |
|       |       | (A)   |       |      | S |      |               |
|       |       | S/I = |       |      |   |      |               |
|       |       | 15 dB |       |      |   |      |               |
|       |       | (D)   |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| Land  | N/S   | N/S   | S/I ≥ | N/S  | N | 47   | Interfering   |
| M     |       |       | 18 dB |      | / | CFR  | signal source |
| obile |       |       |       |      | S | 90   | is a trunked  |
|       |       |       |       |      |   | .187 | radio.        |
+-------+-------+-------+-------+------+---+------+---------------+
| Land  | VHF   | N/S   | S/I ≥ | N/S  | N | 47   | Interferer is |
| M     |       |       | 10 dB |      | / | CFR  | a public      |
| obile |       |       |       |      | S | 80.  | coast         |
|       |       |       |       |      |   | 773b | station.      |
+-------+-------+-------+-------+------+---+------+---------------+
| C4F   | VHF,  | ![](m | N/S   | 12.5 | N | TSB  | Values are    |
| M^I^\ | UHF   | edia/ |       | kHz  | / | 88‑A | for a DAQ =   |
| (I    |       | image |       |      | S | T    | 3.4. This is  |
| MBE)  |       | 6.wmf |       |      |   | able | the criteria  |
|       |       | ){wid |       |      |   |  A‑1 | assumed for   |
|       |       | th="0 |       |      |   |      | federal       |
|       |       | .2777 |       |      |   |      | government    |
|       |       | 77777 |       |      |   |      | operations at |
|       |       | 77777 |       |      |   |      | the boundary  |
|       |       | 78in" |       |      |   |      | of a          |
|       |       | h     |       |      |   |      | protected     |
|       |       | eight |       |      |   |      | service area  |
|       |       | ="0.2 |       |      |   |      | as stated in  |
|       |       | 5in"} |       |      |   |      | TSB88-A       |
|       |       | ≥16.5 |       |      |   |      | (Table 1).    |
|       |       | dB    |       |      |   |      | Other values  |
|       |       | ^II^  |       |      |   |      | for differing |
|       |       |       |       |      |   |      | DAQ are       |
|       |       |       |       |      |   |      | provided in   |
|       |       |       |       |      |   |      | TSB-88 A      |
|       |       |       |       |      |   |      | Table A-1.    |
+-------+-------+-------+-------+------+---+------+---------------+
| C     | VHF,  | ![](m | N/S   | 12.5 | N | TSB  |               |
| QPSK^ | UHF   | edia/ |       |  kHz | / | 88‑A |               |
| III^\ |       | image |       |      | S | T    |               |
| (     |       | 6.wmf |       |      |   | able |               |
| IMBE) |       | ){wid |       |      |   |  A‑1 |               |
|       |       | th="0 |       |      |   |      |               |
|       |       | .2777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 78in" |       |      |   |      |               |
|       |       | h     |       |      |   |      |               |
|       |       | eight |       |      |   |      |               |
|       |       | ="0.2 |       |      |   |      |               |
|       |       | 5in"} |       |      |   |      |               |
|       |       | ≥16.5 |       |      |   |      |               |
|       |       | dB    |       |      |   |      |               |
|       |       | ^II^  |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| π/    | VHF,  | ![](m | N/S   | 12.5 | N | TSB  |               |
| 4^IV^ | UHF   | edia/ |       | kHz  | / | 88‑A |               |
| D     |       | image |       |      | S | T    |               |
| QPSK\ |       | 6.wmf |       |      |   | able |               |
| (     |       | ){wid |       |      |   |  A‑1 |               |
| IMBE) |       | th="0 |       |      |   |      |               |
| TDMA  |       | .2777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 78in" |       |      |   |      |               |
|       |       | h     |       |      |   |      |               |
|       |       | eight |       |      |   |      |               |
|       |       | ="0.2 |       |      |   |      |               |
|       |       | 5in"} |       |      |   |      |               |
|       |       | ≥15.2 |       |      |   |      |               |
|       |       | dB    |       |      |   |      |               |
|       |       | ^II^  |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| EDACS | VHF,  | ![](m | N/S   | 12.5 | N | TSB  |               |
| ®^V^\ | UHF   | edia/ |       |  kHz | / | 88‑A |               |
| (     |       | image |       |      | S | T    |               |
| IMBE) |       | 6.wmf |       |      |   | able |               |
|       |       | ){wid |       |      |   |  A‑1 |               |
|       |       | th="0 |       |      |   |      |               |
|       |       | .2777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 78in" |       |      |   |      |               |
|       |       | h     |       |      |   |      |               |
|       |       | eight |       |      |   |      |               |
|       |       | ="0.2 |       |      |   |      |               |
|       |       | 5in"} |       |      |   |      |               |
|       |       | ≥16.7 |       |      |   |      |               |
|       |       | dB    |       |      |   |      |               |
|       |       | ^VI^  |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| CVSD  | VHF,  | ![](m | N/S   | 25   | N | TSB  |               |
| "XL"^ | UHF   | edia/ |       | kHz  | / | 88‑A |               |
| VII^  |       | image |       |      | S | T    |               |
|       |       | 6.wmf |       |      |   | able |               |
|       |       | ){wid |       |      |   |  A‑1 |               |
|       |       | th="0 |       |      |   |      |               |
|       |       | .2777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 78in" |       |      |   |      |               |
|       |       | h     |       |      |   |      |               |
|       |       | eight |       |      |   |      |               |
|       |       | ="0.2 |       |      |   |      |               |
|       |       | 5in"} |       |      |   |      |               |
|       |       | ≥ 12  |       |      |   |      |               |
|       |       | dB    |       |      |   |      |               |
|       |       | ^     |       |      |   |      |               |
|       |       | VIII^ |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| C4FM  | VHF,  | ![](m | N/S   | 12.5 | N | TSB  |               |
| ^IX^\ | UHF   | edia/ |       |  kHz | / | 88‑A |               |
| (V    |       | image |       |      | S | T    |               |
| SELP) |       | 6.wmf |       |      |   | able |               |
|       |       | ){wid |       |      |   |  A‑1 |               |
|       |       | th="0 |       |      |   |      |               |
|       |       | .2777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 77777 |       |      |   |      |               |
|       |       | 78in" |       |      |   |      |               |
|       |       | h     |       |      |   |      |               |
|       |       | eight |       |      |   |      |               |
|       |       | ="0.2 |       |      |   |      |               |
|       |       | 5in"} |       |      |   |      |               |
|       |       | ≥17.4 |       |      |   |      |               |
|       |       | dB    |       |      |   |      |               |
|       |       | ^X^   |       |      |   |      |               |
+-------+-------+-------+-------+------+---+------+---------------+
| Cel   | 800,  | C/I≥9 | N/S   | N/S  | N | Rec. | N/S           |
| lular | 900,  | dB    |       |      | / | I    |               |
|       | 1800, |       |       |      | S | TU-R |               |
|       | 1900  |       |       |      |   | M.   |               |
|       |       |       |       |      |   | 1073 |               |
+-------+-------+-------+-------+------+---+------+---------------+
| Di    | 1452  | pfd ≤ | N/S   | N/S  | N | Rec. | Rec. notes    |
| gital | -1492 | --150 |       |      | / | I    | that further  |
| LMS   |       | W/m   |       |      | S | TU-R | IPC           |
|       |       | ^2^/4 |       |      |   | M.   | development   |
|       |       | kHz   |       |      |   | 1388 | is needed.    |
+-------+-------+-------+-------+------+---+------+---------------+

+-------+-------+-------+-------+------+----+------+---------------+
| Sys   | Freq  | **In  |       | R    | \% | So   | Comments      |
| tems/ | uency | terfe |       | efer | Ti | urce |               |
|       | Bands | rence |       | ence | me | Docu |               |
| Ser   |       | Pr    |       | b    |    | ment |               |
| vices |       | otect |       | andw |    |      |               |
|       |       | ion** |       | idth |    |      |               |
+=======+=======+=======+=======+======+====+======+===============+
|       |       | CW/   | P     |      |    |      |               |
|       |       | Noise | ulse/ |      |    |      |               |
|       |       |       |       |      |    |      |               |
|       |       |       | Other |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| A     | VHF,  | C/I ≥ | N/S   | N/S  | N  | Rec. | For           |
| nalog | UHF   | 10 dB |       |      | /S | I    | protection    |
| sp    |       |       |       |      |    | TU-R | against       |
| eech, |       |       |       |      |    | SM.8 | analog AM     |
| 12    |       |       |       |      |    | 51-1 | vestigial     |
| .5-25 |       |       |       |      |    |      | sideband TV   |
| kHz   |       |       |       |      |    | (    | and FM sound  |
| cha   |       |       |       |      |    | prov | broadcasting  |
| nnels |       |       |       |      |    | ides |               |
|       |       |       |       |      |    | ad   |               |
|       |       |       |       |      |    | diti |               |
|       |       |       |       |      |    | onal |               |
|       |       |       |       |      |    | IPC  |               |
|       |       |       |       |      |    | for  |               |
|       |       |       |       |      |    | no   |               |
|       |       |       |       |      |    | n-co |               |
|       |       |       |       |      |    | -cha |               |
|       |       |       |       |      |    | nnel |               |
|       |       |       |       |      |    | op   |               |
|       |       |       |       |      |    | erat |               |
|       |       |       |       |      |    | ion) |               |
+-------+-------+-------+-------+------+----+------+---------------+
| π/4   | VHF,  | C/I ≥ | N/S   | N/S  | N  |      | For           |
| QPSK, | UHF   | 11 dB |       |      | /S |      | protection    |
| 50    |       |       |       |      |    |      | against       |
| kHz   |       |       |       |      |    |      | analog AM     |
| chan  |       |       |       |      |    |      | vestigial     |
| nels, |       |       |       |      |    |      | sideband TV   |
| 3 x   |       |       |       |      |    |      | and FM sound  |
| 1     |       |       |       |      |    |      | broadcasting. |
| 0^-2^ |       |       |       |      |    |      | For C/N       |
| BER   |       |       |       |      |    |      | including     |
|       |       |       |       |      |    |      | margin        |
+-------+-------+-------+-------+------+----+------+---------------+
|       |       | C/I ≥ | N/S   | N/S  | N  |      | For           |
|       |       | 17 dB |       |      | /S |      | protection    |
|       |       |       |       |      |    |      | against       |
|       |       |       |       |      |    |      | analog AM     |
|       |       |       |       |      |    |      | vestigial     |
|       |       |       |       |      |    |      | sideband TV   |
|       |       |       |       |      |    |      | and FM sound  |
|       |       |       |       |      |    |      | broadcasting. |
|       |       |       |       |      |    |      | For faded C/N |
+-------+-------+-------+-------+------+----+------+---------------+
| GMSK, | VHF,  | C/I ≥ | N/S   | N/S  | N  |      | For           |
| BT =  | UHF   | 9 dB  |       |      | /S |      | protection    |
| 0.3,  |       |       |       |      |    |      | against       |
| 200   |       |       |       |      |    |      | analog AM     |
| kHz   |       |       |       |      |    |      | vestigial     |
| cha   |       |       |       |      |    |      | sideband TV   |
| nnels |       |       |       |      |    |      | and FM sound  |
|       |       |       |       |      |    |      | broadcasting. |
+-------+-------+-------+-------+------+----+------+---------------+
| P     | VHF   | N/S   | I/S   | N/S  | N  | NTIA | Further       |
| ublic |       |       | V     |      | /S | Re   | analysis is   |
| Corre |       |       | alues |      |    | port | required to   |
| spond |       |       |       |      |    | 00   | determine if  |
| -ence |       |       |       |      |    | -376 | IPC can be    |
| and   |       |       |       |      |    |      | developed.    |
| Auto  |       |       |       |      |    |      |               |
| matic |       |       |       |      |    |      |               |
| Iden  |       |       |       |      |    |      |               |
| tific |       |       |       |      |    |      |               |
| ation |       |       |       |      |    |      |               |
| Sy    |       |       |       |      |    |      |               |
| stems |       |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+

+-------+-------+-------+-------+------+----+------+---------------+
| Sys   | Freq  | **In  |       | R    | \% | So   | Comments      |
| tems/ | uency | terfe |       | efer | Ti | urce |               |
|       | Bands | rence |       | ence | me | Docu |               |
| Ser   |       | Pr    |       | b    |    | ment |               |
| vices |       | otect |       | andw |    |      |               |
|       |       | ion** |       | idth |    |      |               |
+=======+=======+=======+=======+======+====+======+===============+
|       |       | CW/   | P     |      |    |      |               |
|       |       | Noise | ulse/ |      |    |      |               |
|       |       |       |       |      |    |      |               |
|       |       |       | Other |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| 25    | VHF   | N/S   | S/I   | N/S  | N  | NTIA | Further       |
| kHz   |       |       | V     |      | /S | Re   | analysis is   |
| /12.5 |       |       | alues |      |    | port | required to   |
| kHz   |       |       |       |      |    | 97   | determine if  |
|       |       |       |       |      |    | -343 | IPC can be    |
| VHF   |       |       |       |      |    |      | developed.    |
| R     |       |       |       |      |    |      |               |
| adios |       |       |       |      |    |      |               |
+-------+-------+-------+-------+------+----+------+---------------+
| 25    | VHF   | N/S   | S/I   | N/S  | N  | NTIA | Further       |
| kHz   |       |       | V     |      | /S | Re   | analysis is   |
| R     |       |       | alues |      |    | port | required to   |
| adios |       |       |       |      |    | 99   | determine if  |
|       |       |       |       |      |    | -363 | IPC can be    |
|       |       |       |       |      |    |      | developed.    |
+-------+-------+-------+-------+------+----+------+---------------+
| P     | VHF   | N/S   | C/I ≥ | N/S  | N  | 47   | This applies  |
| ublic |       |       | 12 dB |      | /S | CFR  | to a          |
| coast |       |       |       |      |    | 80.  | subsequent    |
| st    |       |       |       |      |    | 773a | coast         |
| ation |       |       |       |      |    |      | station's     |
|       |       |       |       |      |    |      | allowable     |
|       |       |       |       |      |    |      | signal level  |
|       |       |       |       |      |    |      | within the    |
|       |       |       |       |      |    |      | service area  |
|       |       |       |       |      |    |      | of the        |
|       |       |       |       |      |    |      | incumbent     |
|       |       |       |       |      |    |      | \[may not be  |
|       |       |       |       |      |    |      | true IPC\].   |
+-------+-------+-------+-------+------+----+------+---------------+
| AMS   | 17.97 | N/S   | D/U ≥ | N/S  | N  | ICAO | Intended to   |
|       | 5‑137 |       | 14 dB |      | /S |      | establish     |
|       | MHz   |       |       |      |    | A    | distance      |
|       |       |       |       |      |    | nnex | separation    |
|       |       |       |       |      |    | 10,  | between       |
|       |       |       |       |      |    | Vol. | aeronautical  |
|       |       |       |       |      |    | 5,   | facilities.   |
|       |       |       |       |      |    | 4.1. |               |
|       |       |       |       |      |    | 5.1, |               |
|       |       |       |       |      |    |      |               |
|       |       |       |       |      |    | page |               |
|       |       |       |       |      |    | 8    |               |
+-------+-------+-------+-------+------+----+------+---------------+

+-----------------------------------------------------------------------+
| D= Digital; A=Analog                                                  |
|                                                                       |
| \* UWC refers to the IMT-2000 Radio Interface "UWC-136".              |
|                                                                       |
| ^I^ C4FM/IMBE/VSELP = A 4-ary FM modulation technique that produces   |
| the same phase shift as a compatible CQPSK modulation technique.      |
| Consequently, the same receiver may receive either modulation.        |
| IMBE-The acronym for Improved Multi Band Excitation, the project 25   |
| standard vocoder per ANSI/TIA/EIA-102.BABA. "A voice coding technique |
| based on Sinusoidal Transform Coding (analog to digital voice         |
| conversion)."                                                         |
|                                                                       |
| ^II^ BER = 2%                                                         |
|                                                                       |
| ^III^ CQPSK: = The acronym for Compatible, Quadrature Phase Shift Key |
| (QPSK) AM. An emitter that uses QPSK-c modulation that allows         |
| compatibility with a frequency discriminator detection receiver.      |
|                                                                       |
| ^IV^ π/4 DQPSK = The acronym for "Differential Quadrature Phase Shift |
| Keying", "Quadrature" indicates that the phase shift of the           |
| modulation is a multiple of 90 degrees. Differential indicates that   |
| consecutive symbols are phase shifted 45 degrees (π/4) from each      |
| other.                                                                |
|                                                                       |
| ^V^ EDACS = Enhanced Digital Access Communication System              |
|                                                                       |
| ^VI^ BER = 2.8 %                                                      |
|                                                                       |
| ^VII^ CVSD = Continuously variable slope delta modulation: A type of  |
| delta modulation in which the size of the steps of the approximated   |
| signal is progressively increased or decreased as required to make    |
| the approximated signal closely match the input analog wave.          |
|                                                                       |
| ^VIII^ BER = 3%                                                       |
|                                                                       |
| ^IX^ VSELP -Vector-Sum-Excited Linear Prediction                      |
|                                                                       |
| ^X^ BER = 1.4%                                                        |
+-----------------------------------------------------------------------+

+-----------+-------+--------+-----+-------+----+------+-----------+
| Services  | Freq  | Interf |     | Refe  | \% | So   | Comments  |
| /Systems  | uency | erence |     | rence | Ti | urce |           |
|           | Bands | Prot   |     | Band  | me | Docu |           |
|           |       | ection |     | width |    | ment |           |
+===========+=======+========+=====+=======+====+======+===========+
|           |       | CW/    | Pul |       |    |      |           |
|           |       |        | se/ |       |    |      |           |
|           |       | Nois   |     |       |    |      |           |
|           |       | e-like | Ot  |       |    |      |           |
|           |       |        | her |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
| GSO/MSS,  | 1-3   | I~ag   | N/S | N/S   | N  | R    | MSS       |
| GS        | GHz   | g~/N~B |     |       | /S | ecs. | system    |
| O/AMS(R)S |       | ER~^i^ |     |       |    | I    | without   |
|           |       | ≤      |     |       |    | TU-R | frequency |
|           |       |        |     |       |    | M.1  | reuse.    |
|           |       | --6.2  |     |       |    | 183, | I~agg~    |
|           |       | dB     |     |       |    | M.   | from      |
|           |       |        |     |       |    | 1234 | other MSS |
|           |       |        |     |       |    |      | systems   |
|           |       |        |     |       |    |      | and FSS   |
|           |       |        |     |       |    |      | systems.  |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I      |     |       |    |      | Victim    |
|           |       | ~agg~/ |     |       |    |      | system    |
|           |       | N~BER~ |     |       |    |      | with      |
|           |       | ≤      |     |       |    |      | frequency |
|           |       |        |     |       |    |      | reuse.    |
|           |       | --7 dB |     |       |    |      | I~agg~    |
|           |       |        |     |       |    |      | from      |
|           |       |        |     |       |    |      | other MSS |
|           |       |        |     |       |    |      | systems   |
|           |       |        |     |       |    |      | and FSS   |
|           |       |        |     |       |    |      | systems.  |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~se~/ |     |       |    |      | I~se~     |
|           |       | N~BER~ |     |       |    |      | from      |
|           |       | ≤      |     |       |    |      | another   |
|           |       |        |     |       |    |      | MSS       |
|           |       | --12.2 |     |       |    |      | system or |
|           |       | dB     |     |       |    |      | FSS       |
|           |       |        |     |       |    |      | system.   |
+-----------+-------+--------+-----+-------+----+------+-----------+
| GS        | 1545  | I      | N/S | N/S   | N  | Rec. | I~agg~    |
| O/AMS(R)S | -1555 | ~agg~/ |     |       | /S | I    | and I~se~ |
|           | and   | N~BER~ |     |       |    | TU-R | from      |
|           | 16    | ≤      |     |       |    | M.   | other     |
|           | 46.5- |        |     |       |    | 1234 | AMS(R)S,  |
|           | 1     | --7    |     |       |    |      | AMSS, and |
|           | 656.5 | dB,    |     |       |    |      | FSS.      |
|           | MHz   |        |     |       |    |      |           |
|           |       | I~se~/ |     |       |    |      |           |
|           |       | N~BER~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | --12.2 |     |       |    |      |           |
|           |       | dB     |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
| NGSO/MSS  | 13    | I~agg~ | N/S | 44    | 20 | R    | Victim    |
| downlink  | 7-138 | ≤      |     | kHz   |    | ecs. | system A  |
|           | MHz   |        |     |       |    | I    | ^iv^      |
|           |       | -      |     |       |    | TU-R |           |
|           |       | -142.1 |     |       |    | M.1  |           |
|           |       | dBW    |     |       |    | 231, |           |
|           |       |        |     |       |    |      |           |
|           |       |        |     |       |    | M.   |           |
|           |       |        |     |       |    | 1232 |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~     |     |       |    |      |           |
|           |       | se,\ N |     |       |    |      |           |
|           |       | GSO/MS |     |       |    |      |           |
|           |       | S~^ii^ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -146.2 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I      |     |       |    |      |           |
|           |       | ~se,\  |     |       |    |      |           |
|           |       | terres |     |       |    |      |           |
|           |       | trial~ |     |       |    |      |           |
|           |       | ^iii^  |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -147.3 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+

+-----------+-------+--------+-----+-------+----+------+-----------+
| Services  | Freq  | Interf |     | Refe  | \% | So   | Comments  |
| /Systems  | uency | erence |     | rence | Ti | urce |           |
|           | Bands | Prot   |     | Band  | me | Docu |           |
|           |       | ection |     | width |    | ment |           |
+===========+=======+========+=====+=======+====+======+===========+
|           |       | CW/    | Pul |       |    |      |           |
|           |       |        | se/ |       |    |      |           |
|           |       | Nois   |     |       |    |      |           |
|           |       | e-like | Ot  |       |    |      |           |
|           |       |        | her |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
| NGSO/MSS  | 13    | I~agg~ | N/S | 44    | 0. | R    | Victim    |
| downlink  | 7-138 | ≤-     |     | kHz   | 25 | ecs. | system A  |
|           | MHz   | -133.4 |     |       |    | I    |           |
|           |       | dBW    |     |       |    | TU-R |           |
|           |       |        |     |       |    | M.1  |           |
|           |       |        |     |       |    | 231, |           |
|           |       |        |     |       |    |      |           |
|           |       |        |     |       |    | M.   |           |
|           |       |        |     |       |    | 1232 |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~se   |     |       | 0. |      |           |
|           |       | ,\ NGS |     |       | 06 |      |           |
|           |       | O/MSS~ |     |       | 25 |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -133.8 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I      |     |       | 0  |      |           |
|           |       | ~se,\  |     |       | .1 |      |           |
|           |       | terres |     |       | 25 |      |           |
|           |       | trial~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -133.8 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~agg~ | N/S | 19.2  | 20 |      | Victim    |
|           |       | ≤      |     | kHz   |    |      | system B  |
|           |       |        |     |       |    |      | ^v^       |
|           |       | -      |     |       |    |      |           |
|           |       | -155.3 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~se   |     |       |    |      |           |
|           |       | ,\ NGS |     |       |    |      |           |
|           |       | O/MSS~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -159.9 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I      |     |       |    |      |           |
|           |       | ~se,\  |     |       |    |      |           |
|           |       | terres |     |       |    |      |           |
|           |       | trial~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -160.6 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~agg~ |     |       | 0. |      |           |
|           |       | ≤      |     |       | 25 |      |           |
|           |       |        |     |       |    |      |           |
|           |       | --144. |     |       |    |      |           |
|           |       | 5 dBW  |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~se   |     |       | 0. |      |           |
|           |       | ,\ NGS |     |       | 06 |      |           |
|           |       | O/MSS~ |     |       | 25 |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -144.7 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I      |     |       | 0  |      |           |
|           |       | ~se,\  |     |       | .1 |      |           |
|           |       | terres |     |       | 25 |      |           |
|           |       | trial~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -144.8 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~agg~ | N/S | 885   | 20 |      | Victim    |
|           |       | ≤      |     | kHz   |    |      | system C  |
|           |       |        |     |       |    |      | ^vi^      |
|           |       | -      |     |       |    |      |           |
|           |       | -134.5 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~se   |     |       |    |      |           |
|           |       | ,\ NGS |     |       |    |      |           |
|           |       | O/MSS~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -138.5 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I      |     |       |    |      |           |
|           |       | ~se,\  |     |       |    |      |           |
|           |       | terres |     |       |    |      |           |
|           |       | trial~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -141.5 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I~agg~ |     |       | 0. |      |           |
|           |       | ≤      |     |       | 25 |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -128.5 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+

+-----------+-------+--------+-----+-------+----+------+-----------+
| Services  | Freq  | Interf |     | Refe  | \% | So   | Comments  |
| /Systems  | uency | erence |     | rence | Ti | urce |           |
|           | Bands | Prot   |     | Band  | me | Docu |           |
|           |       | ection |     | width |    | ment |           |
+===========+=======+========+=====+=======+====+======+===========+
|           |       | CW/    | Pul |       |    |      |           |
|           |       |        | se/ |       |    |      |           |
|           |       | Nois   |     |       |    |      |           |
|           |       | e-like | Ot  |       |    |      |           |
|           |       |        | her |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
| NGSO/MSS  | 13    | I~se   | N/S | 885   | 0. | R    | Victim    |
| downlink  | 7-138 | ,\ NGS |     | kHz   | 06 | ecs. | system C  |
|           | MHz   | O/MSS~ |     |       | 25 | I    |           |
|           |       | ≤      |     |       |    | TU-R |           |
|           |       |        |     |       |    | M.1  |           |
|           |       | --129  |     |       |    | 231, |           |
|           |       | dBW    |     |       |    |      |           |
|           |       |        |     |       |    | M.   |           |
|           |       |        |     |       |    | 1232 |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | I      |     |       | 0  |      |           |
|           |       | ~se,\  |     |       | .1 |      |           |
|           |       | terres |     |       | 25 |      |           |
|           |       | trial~ |     |       |    |      |           |
|           |       | ≤      |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|           |       | -      |     |       |    |      |           |
|           |       | -129.5 |     |       |    |      |           |
|           |       | dBW    |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
| COSP      | 406-  | Max    | N/S | N/A   | N  | Rec. | In        |
| AS/SARSAT | 406.1 | spfd ≤ |     |       | /S | I    | terfering |
|           | MHz   |        |     |       |    | TU-R | system A  |
|           |       | -      |     |       |    | M.   | ^vii^     |
|           |       | -198.6 |     |       |    | 1478 |           |
|           |       | d      |     |       |    |      |           |
|           |       | BW/(m^ |     |       |    |      |           |
|           |       | 2^·Hz) |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | Max    |     | 19 Hz |    |      | In        |
|           |       | pfd =  |     |       |    |      | terfering |
|           |       |        |     |       |    |      | system B  |
|           |       | -      |     |       |    |      | ^viii^    |
|           |       | -185.8 |     |       |    |      |           |
|           |       | dB     |     |       |    |      |           |
|           |       | W/m^2^ |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
| COSP      |       | Max    |     | N/A   |    |      | In        |
| AS/SARSAT |       | spfd = |     |       |    |      | terfering |
|           |       |        |     |       |    |      | system A  |
|           |       | -      |     |       |    |      |           |
|           |       | -200.8 |     |       |    |      |           |
|           |       | d      |     |       |    |      |           |
|           |       | BW/(m^ |     |       |    |      |           |
|           |       | 2^·Hz) |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
|           |       | Max    |     | 40 Hz |    |      | In        |
|           |       | pfd =  |     |       |    |      | terfering |
|           |       |        |     |       |    |      | system B  |
|           |       | -      |     |       |    |      |           |
|           |       | -176.6 |     |       |    |      |           |
|           |       | dB     |     |       |    |      |           |
|           |       | W/m^2^ |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+
| i.        |       |        |     |       |    |      |           |
|   I~agg~: |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
| aggregate |       |        |     |       |    |      |           |
|     in    |       |        |     |       |    |      |           |
| terfering |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|    signal |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|    power; |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|   N~BER~: |       |        |     |       |    |      |           |
|     total |       |        |     |       |    |      |           |
|     noise |       |        |     |       |    |      |           |
|     power |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|    giving |       |        |     |       |    |      |           |
|     rise  |       |        |     |       |    |      |           |
|     to    |       |        |     |       |    |      |           |
|     the   |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
| objective |       |        |     |       |    |      |           |
|     BER;  |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|    I~se~: |       |        |     |       |    |      |           |
|     sin   |       |        |     |       |    |      |           |
| gle-entry |       |        |     |       |    |      |           |
|     in    |       |        |     |       |    |      |           |
| terfering |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|    signal |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
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|           |       |        |     |       |    |      |           |
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|           |       |        |     |       |    |      |           |
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|           |       |        |     |       |    |      |           |
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|           |       |        |     |       |    |      |           |
|     below |       |        |     |       |    |      |           |
|       406 |       |        |     |       |    |      |           |
|           |       |        |     |       |    |      |           |
|      MHz. |       |        |     |       |    |      |           |
+-----------+-------+--------+-----+-------+----+------+-----------+

**REFERENCES**

#  SCIENCE SERVICES

## INTRODUCTION

Science services include the space research service, inter-satellite
service, space operations service, meteorological aids service, Earth
exploration-satellite (EES) and meteorological-satellite (METSAT)
services, and radio astronomy service. Space research services include
deep space, near earth and data relay satellite (DRS) satellite
services. EES and METSAT services include command and data,
space-to-Earth data, data dissemination and direct readout, and passive
and active sensors. Various ITU-R Recommendations specify IPC for these
services for noise-like or CW-type interfering signals in a specified
reference bandwidth. No IPC were found for pulse or impulse type
interfering signals.

## SPACE RESEARCH SERVICE

The space research service supports diverse scientific and technology
programs that provide information about the solar system, the nature and
structure of the universe, and the origin and fate of matter. The
systems include manned and unmanned spacecraft, communication networks
on the surface of the Earth, and spacecraft in various orbits or
trajectories. Spacecraft further than 2 X 10^6^ km from the Earth are
referred to as "deep space" spacecraft.

The phases of space research missions potentially having different
requirements include pre-launch checkout, launch operations, transfer
operations, on-orbit operations and landing operations. Communication
links for command, telemetry and tracking data are variously required
between co-orbiting spacecraft and between the spacecraft and earth
stations either directly or through Data Relay Satellites (DRS).

Phase-lock loops are extensively used in space research communication
systems. Because a strong interfering signal component can cause the
receiver to lock to the interfering signal rather than the desired
signal, narrow reference bandwidths are specified in the IPC. Protection
criteria for space research services are given in Recs. ITU-R SA.363,
SA.609, SA.1155, SA.1157, and SA.1396.[^138]

### Deep-Space Research

IPC for deep-space research systems are given in Rec. ITU-R SA.1157.
There are four receiver subsystems in deep-space earth stations that are
particularly sensitive to interfering signals: maser pre-amplifier,
carrier tracking loop, telemetering subsystem and ranging subsystem. To
ensure proper operation, each of the four subsystems must be protected
against interference. The IPC specifies the amount of interfering signal
power that will result in a maximum acceptable degradation of
performance.

The gain of maser pre-amplifiers typically used in deep space earth
station receivers is reduced by strong interfering signals, which also
results in non-linear operation. The response of the carrier tracking
loop is an increase in phase error and jitter that can cause loss of
lock. The degradation of telemetry bit error performance and ranging
accuracy as a result of interfering signals can be expressed in terms of
a reduction in signal-to-noise ratio. Table 8-1 summarizes the maximum
acceptable performance degradation.

**Table 8-1**

Maximum Acceptable Degradation of Receiver Subsystems

+-----------------------------------+----------------------------------+
| Receiving Subsystem               | Maximum Acceptable Degradation   |
+-----------------------------------+----------------------------------+
| Maser pre-amplifier               | 1 dB gain compression            |
|                                   |                                  |
| Carrier tracking                  | 10^o^ loop static phase error or |
|                                   | peak phase jitter                |
+-----------------------------------+----------------------------------+
| Telemetry                         | 1 dB equivalent reduction in     |
|                                   | symbol energy to noise spectral  |
|                                   | density increase (ΔE/N~o~ = --1  |
|                                   | dB)                              |
+-----------------------------------+----------------------------------+
| Ranging                           | 1 dB equivalent reduction in     |
|                                   | symbol energy to noise spectral  |
|                                   | density                          |
|                                   |                                  |
|                                   | increase (ΔE/N~o~ = --1 dB)      |
+-----------------------------------+----------------------------------+

The amount of interfering signal power that can cause the degradation
shown in Table 8-1 is given in Annex 2 of Rec. ITU-R SA.1157 for CW and
noise-like interfering signals. Table 8-2 shows the maximum allowable
interference-to-carrier ratio (I/C), interference-to-signal ratio (I/S)
or interference-to-noise ratio (I/N) that corresponds to maximum
acceptable degradation of carrier tracking, telemetry and ranging
subsystems. From Table 8-2, the maximum allowable CW interfering signal
power is dictated by the carrier tracking loop. For carrier tracking,
the maximum permissible power of noise-like interfering signals have
been calculated from maximum I/C, receiver noise spectral density,
carrier tracking loop bandwidth and minimum C/N ratio required for
carrier tracking. The resulting IPC are summarized in Table 8-3.

**Table 8-2**

Basis for IPC for CW and Noise-like Interfering Signals

at Deep Space Earth Stations

+------------------------+----------------------+----------------------+
| Subsystem (criterion)  | Interfering Signal   | IPC                  |
|                        | Type                 |                      |
+------------------------+----------------------+----------------------+
| Carrier tracking       | CW                   | I/C ≤ -- 15 dB       |
|                        |                      |                      |
| (10^o^ added peak      | Noise-like           | I/N ≤ + 2.3 dB       |
| phase jitter)          |                      |                      |
+------------------------+----------------------+----------------------+
| Telemetry              | CW                   | I/C ≤ -- 1.5 dB      |
|                        |                      |                      |
| (1 dB reduction in     |                      |                      |
| E/N~o~ from            |                      |                      |
| interfering signal in  |                      |                      |
| carrier tracking loop) |                      |                      |
+------------------------+----------------------+----------------------+
| Telemetry              | CW                   | I/S ≤ --11 dB        |
|                        |                      |                      |
| (1 dB reduction in     | Noise-like           | I/N ≤ -- 5.9 dB      |
| E/N~o~ from            |                      |                      |
| interfering signal in  |                      |                      |
| telemetry detection    |                      |                      |
| bandwidth)             |                      |                      |
+------------------------+----------------------+----------------------+
| Ranging                | CW                   | I/C ≤ -- 5 dB        |
|                        |                      |                      |
| (1 dB reduction in     |                      |                      |
| E/N~o~ from            |                      |                      |
| interfering signal in  |                      |                      |
| carrier tracking loop) |                      |                      |
+------------------------+----------------------+----------------------+
| Ranging                | CW                   | I/S ≤ -- 7.1 dB      |
|                        |                      |                      |
| (1 dB reduction in     | Noise-like           | I/N ≤ -- 5.9 dB      |
| E/N~o~ from            |                      |                      |
| interfering signal in  |                      |                      |
| range estimator        |                      |                      |
| bandwidth)             |                      |                      |
+------------------------+----------------------+----------------------+

The IPC for deep-space station receivers are based on an I/N of 0 dB.
Unlike for the space-to-Earth links, substantial power margins are
available on the Earth-to-space links.

### Near Earth Space Research

The permissible I/N ratio in a near-earth space research communication
link is determined by the portion of the link margin allocated to
interfering signals. Typical link margins range from 3 to 6 dB for
frequencies below 10 GHz and larger margins are used at higher
frequencies. Interference can be harmful if the link power margin is
decreased by more than 1 dB. This corresponds to an I/N of --6 dB. The
reference bandwidth for the IPC depends upon the smallest bandwidth
likely to be employed. For manned space missions, a loss of more than 5
minutes of communication during critical periods of the mission would
seriously affect the mission. To prevent interference for longer than 5
minutes per day, it is necessary not only to consider the worst hour in
the year, but the worst 5 minutes within that hour. This corresponds to
0.001% of the time for manned space missions, whereas, for unmanned
space missions up to 0.1% of outage can be tolerated.

In the 1-20 GHz range, the system noise temperature of receiving earth
stations is typically as low as 70 K. Below about 1 GHz, cosmic noise
increases the operating noise temperature of the system at a rate of
about 20 dB per decade of decreasing frequency. The system noise
temperature of a permissible space-station receiver is usually 600 K or
more, partly due to the fact that the spacecraft antenna points at the
Earth (290 K). The resulting IPC for near-earth research are given in
Rec. ITU-R SA.609 and summarized in Table 8-3.

### Data Relay Satellites

Data relay satellites operate in the space research, space operation,
Earth exploration-satellite (EES) and the fixed-satellite (FSS)
services. A link margin reduction of 0.4 dB has been used as a basis for
the IPC. This corresponds to an I/N within the reference bandwidth of
--10 dB. The IPC for data relay satellite systems are given in Rec.
ITU-R SA.1155, and summarized in Table 8-3.

### Telecommunication Links in the 37-40 GHz Bands

The frequency bands 37-38 GHz and 40-40.5 GHz have been allocated to the
space research service on a primary basis worldwide. These bands are
intended to be used for high-rate digital data transfer of telemetry,
voice, and video between the Earth and other planetary bodies such as
the Moon and Mars to support manned exploration. Further, the 37-38 GHz
band is to be used for high-rate data transfer from an earth-orbiting
S-VLBI station. Data rates of the order of 100 Mbits/s from planetary
ranges, 500 Mbits/s for lunar ranges and 1000 Mbits/s from S-VLBI
station to earth are expected.

For space-to-Earth links, typical link power margins are 2 to 4 dB.
Therefore, during desired signal fading, interference can be severe if
the link margin is lowered by more than 1 dB. This corresponds to an I/N
ratio of about

-6 dB. For Earth-to-space links, which are not power limited, up to 3 dB
degradation may be tolerated (I/N of 0 dB). The reference bandwidths for
earth-station and space-station receivers are 1 Hz and 20 Hz
respectively. The percentage of time during which these thresholds may
be exceeded are 0.001% of time for manned missions and 0.1% of time for
unmanned missions.

In the 37-38 GHz region, the IPC are based on a 60 K system noise
temperature for receiving earth stations. In the 40-40.5 GHz range, the
IPC for space research space station are derived from a noise
temperature of 200 K and an I/N ratio of 0 dB. The IPC for space
research service in the 37-40 GHz range are given in Rec. ITU-R SA.1396
and are summarized in Table 8-3.

## SPACE OPERATION SERVICE

The space operation service is a radiocommunication service concerned
exclusively with the operation of spacecraft, in particular tracking,
telemetry and telecommand. These functions are normally provided within
the frequency allocations for the services in which the space station is
operating. The preferred frequency bands for space operations lie
approximately between 1 and 8 GHz. Lower frequencies are sometimes used
for spacecraft that do not require high precision tracking. Frequencies
above 10 GHz are suitable for space operation services during the
re-entry of spacecraft into the atmosphere of the Earth.

The reference bandwidth is based on phase-locked loop receivers having
equivalent noise bandwidths of between a few hundred Hz and a few
kilohertz. A value of 1 kHz has been adopted for the reference
bandwidth. Generally, the percentage of time during which space
operation links can tolerate interfering signal power above the
protection level is fixed at 1% per day, approximately equivalent to 15
minutes per day. However, interference lasting for 15 consecutive
minutes may be intolerable during critical stages.

Above 1 GHz, the total noise temperature of earth stations is 100 K. The
IPC are based on that noise temperature and an I/N of --5 dB. Since the
power of earth station transmitters can generally be increased within
limits imposed by the Radio Regulations on-board receivers do not always
operate at maximum sensitivity. The protection of space station
receivers is therefore expressed in terms of protection ratios and the
IPC are based on an S/I ratio of 20 dB. IPC for space operation systems
are given in Rec. ITU-R SA.363 and are summarized in Table 8-3.

## METEOROLOGICAL AIDS

The term MetAids is used to describe a variety of meteorological
equipment, such as, radiosondes, dropsondes, rocketsondes and weather
radars. IPC for weather radars are discussed separately in Section 5 due
to their similarity to radiodetermination service radars. Other MetAids
are flown worldwide for the collection of upper atmosphere
meteorological data for weather forecasts, ozone monitoring, and other
applications.

IPC for MetAids are based on the link margin at the maximum slant range.
The first level of interfering signal power is the level associated with
loss of receiver lock, which may be exceeded only for 0.02% of time. The
second level of interfering signal power is the level at which loss of
data will occur. The percentage of time for this occurrence may be
obtained from the user's data availability objectives, typically 1.25%
of time for radiosondes and 0.03% for dropsondes. The third interfering
signal level will be the long-term level, at 20% of the time, which may
result in data loss during desired signal fading. The IPC and underlying
calculation methodology are given in Rec. ITU-R SA.1263.[^139]

## EARTH EXPLORATION-SATELLITE AND METEOROLOGICAL SATELLITE SERVICES 

Systems in earth exploration-satellite service (EES) and meteorological
satellite service (METSAT) utilize transmission systems having various
Earth-to-space, space-to-space, and space-to-Earth links. These services
support data collection, data dissemination, interrogation of data
collection platforms, passive sensing, active sensing, direct data
readout and recorded data acquisition. The methodology for determining
IPC is given in Rec. ITU-R SA.1022.[^140]

### Space-to-Earth Data Transmission Systems Using Low-Earth Orbit

Using the performance criteria for space-to-Earth data transmission
systems given in Rec. ITU-R SA.1025 and the methodology given in Rec.
ITU-R SA.1022, IPC have been developed for METSAT and EES in different
bands. [^141]

For METSAT service in the 137-138 MHz band, the automatic picture
transmission (APT) system uses analog modulation with a bandwidth of 50
kHz and is planned to be phased out in 2005. Its replacement is the low
resolution picture transmission (LRPT) system which uses digital
modulation with a nominal data rate of 72 kbit/s. Two types of earth
stations are used in this band, one with an unsteered low gain antenna
for reception of local data and the other with a steerable medium gain
antenna for reception of regional data.

For METSAT service in the 400.15-401 MHz band, data from spacecraft
sensors is multiplexed into a data stream at a rate of 88.75 kb/s. The
typical earth stations are mobile with 0 dBi antenna gain.

For METSAT service in the 1670-1710 MHz band and EES in the 1690-1710
MHz band, the high resolution picture transmission (HRPT) system and the
command and data acquisition system (CDA) use small and large earth
stations respectively. For the large station, a 2.667 Mbit/s data rate
is used and for the small station a data rate of 0.667 Mbit/s is used,
and higher data rates are planned.

In the 7450-7550 MHz a global recorded data (GRD) system expected to be
implemented around 2005. IPC are based on the system design parameters.

The EES service at 8025-8400 MHz uses two systems. For "System A," a
major data acquisition facility receives stored data and the low cost
facility receives real time regional data. For "System B," a major data
acquisition facility is also used to receive wideband (420 Mbit/s)
direct data readout.

The IPC for space-to-Earth data transmission systems operating in METSAT
and EES services using satellites in low-Earth orbits are given in Rec.
ITU-R SA.1026 and are summarized in Table 8-3.[^142]

### Data Dissemination and Direct Data Readout Systems Using Geostationary Satellites

For direct readout systems, all of the interfering signals enter the
receiving earth station directly. (The data originates at the satellite
and none is received via satellite retransmission.) Dissemination of
high-resolution processed data and lower resolution weather facsimile
(WEFAX) data is affected by the interfering signal power received at the
station via the satellite as well as directly by the earth station in
the 1670-1710 MHz band. These data are up-linked to the satellite in the
2025-2110 MHz band, and relayed, along with interfering signals entering
the satellite in the same band, to the earth station receivers via fixed
gain satellite transponders.

For links in the EES and MetSat services using geostationary orbits, the
performance objectives are given in Rec. ITU-R SA.1159.[^143] IPC have
been determined using the methodology given in Rec. ITU-R SA.1022. The
IPC for data dissemination and direct data readout systems in the EES
and METSAT services are given in Rec. ITU-R SA.1160-2 and are summarized
in Table 8-3.[^144]

### Service Links in Data Collection Systems

Systems for data collection and platform location in the EES and METSAT
services collect data for users needing information from a variety of
sources, which may be located anywhere in the world. Two types of orbits
are used: low earth orbits (LEO) and geostationary-satellite orbit
(GSO). The GSO systems provide data with a delivery delay of typically 5
minutes, but do not cover the polar region. The LEO systems offer
worldwide coverage as well as the platform location with a delivery
delay of up to 1 to 3 hours.

Telecommunication requirements and performance objectives for service
links in data collection and platform location are given in Rec. ITU-R
SA.1162.[^145] Using the methodology described in Rec. ITU-R SA.1022,
the IPC are given in Rec. ITU-R SA.1163 and are summarized in Table
8-3.[^146]

### Command and Data Transmission System

For all command and data transmission systems in bands other than those
treated in Recs. SA.1026, SA.1160 and SA.1163, the IPC for earth
receiving sites and for near-earth spacecraft are given in Rec. ITU-R
SA.514 and are summarized in Table 8-3.[^147]

### Satellite Passive Remote Sensing 

Passive sensing is the measurement of natural emissions from the Earth
and its atmosphere. Certain frequency bands coinciding with these
emissions have been allocated for spaceborne passive microwave remote
sensing. These include some absorption bands for atmospheric gases (O~2~
and H~2~O). Measurements in the absorption band are extremely vulnerable
to interference because there is very little possibility to detect and
reject data that are contaminated by interference. The use of
contaminated data in numerical weather prediction (NWP) would have an
adverse effect on the quality of weather forecasting.

The sensitivities of radiometric passive sensors are generally expressed
as a temperature differential, ΔT~e~. The minimum discernable power
change is given by:

> ΔP = k ΔT~e~ B Watts (8-3)

Where, k is the Boltzmann's constant and B is the receiver bandwidth in
Hz. Harmful interference to passive sensors may occur when unwanted
signal levels exceed 20% of ΔP, which is a basis for the IPC.
Measurement sensitivities suitable for passive sensing of land, oceans
and atmosphere within their allocated bands are given in Rec. ITU-R
SA.1028.[^148] The permissible interference levels and reference
bandwidths are given in Rec. ITU-R SA.1029, and are summarized in Table
8-3.[^149]

### Spaceborne Active Microwave Remote Sensors 

The performance requirements for active sensors can be stated in terms
of measurement precision and availability. The performance criteria for
various active sensors are as follows.

Synthetic Aperture Radars (SAR): near 400 MHz, a performance criterion
for SARs is to collect SAR imagery with a minimum reflectivity of --39
dB.

Altimeters: near 5.3 GHz, 13-14 GHz and 35.5-36.0 GHz, a performance
criterion for altimeters is to measure the sea level with a precision of
at least 3 cm. An increase in height noise of 0.1 cm, corresponding to
4% degradation in height noise in the presence of a systematic height
noise of 2-2.4 cm, would be consistent with mission objectives.

Scatterometers: near 5.3 GHz, 13-14 GHz and 35.5-36.0 GHz, the
performance criterion for scatterometers is measurement of wind speeds
greater than or equal to 3 m/s.

Precipitation radars: the science requirement for precipitation radars
is to achieve, after data processing, measurement of rain rates equal to
or greater than 0.7 mm/h in the 13-14 GHz band and 0.15 mm/h in the
35.5-36.0 GHz band. An increase in measurable rain rate to 0.75 mm/h in
the 13-14 GHz band and 0.2 mm/h in the 35.5-36.0 GHz band would not
materially affect the data and would be acceptable as a basis for IPC.

Cloud profiling radars: at 35.5-36.0 GHz and 94-94.1 GHz, the
performance criterion for cloud profiling radars is to measure the
reflectivity profile for all clouds within the field of view with a
minimum reflectivity of

-30 dBZ. A degradation of minimum measurable reflectivity (*Z*~min~) by
less than 10% due to interference would be consistent with mission
objectives.

IPC for active sensors and their technical bases are given in Rec. ITU-R
SA.1166-2.[^150] The IPC are given in Table 8-3.

## RADIO ASTRONOMY

Radio astronomical measurements are made from the Earth's surface from 2
MHz to 800 GHz and from space platforms at frequencies which extend down
to lower than 10 kHz.

The sensitivity of the receivers used for radio astronomy greatly
exceeds the sensitivity of typical communications and radar equipment.
The sensitivity is defined by the smallest power level change ΔP at the
input which can be detected and measured. The interfering signal
threshold levels are defined as the interfering signal level which
introduces an error of 10% in the measurement of ΔP. The IPC are based
on assumed integration time of 2000 seconds and 0 dBi antenna gain
toward the interferer. Integration times actually used in astronomical
observations cover a wide range of values. The IPC for radio
astronomical measurements are given in Rec. ITU-R RA.769.[^151]

Interfering signals received by widely-spaced antennas used for Very
Long Baseline Interferometry (VLBI) will undergo different relative time
delays before they are recombined. Compared to a single antenna radio
telescope, the interferometer has a greater degree of immunity, which
increases with the size of the array in wavelengths. In VLBI, the
separation of antennas is such that the chance of occurrence of
correlated interfering signals is very small. The tolerable interfering
signal level is determined by the requirement that the power level of
the interfering signals should be less than 1% of the receiver noise
power to prevent serious errors. Large interferometers and arrays are
generally used to study discrete high brightness sources, with angular
dimensions no more than a few tenths of a second of arc for VLBI. The
IPC for VLBI are given in Rec. ITU-R RA.769.

## SUMMARY

Table 8-3 provides a summary of the IPC for the science services.

+---------+-------+--------+-----+------+-----+-------+-----------+
| S       | Freq  | Interf |     | R    | \%  | S     | Comments  |
| ervices | uency | erence |     | efer |     | ource |           |
|         |       | P      |     | ence | T   | Doc   |           |
| Systems | Bands | rotect |     | BW   | ime | ument |           |
|         |       | ion^i^ |     |      |     |       |           |
+=========+=======+========+=====+======+=====+=======+===========+
|         |       | CW &   | Pu  |      |     |       |           |
|         |       | Noi    | lse |      |     |       |           |
|         |       | selike |     |      |     |       |           |
|         |       |        | Ot  |      |     |       |           |
|         |       |        | her |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
| SPACE   |       |        |     |      |     |       |           |
| R       |       |        |     |      |     |       |           |
| ESEARCH |       |        |     |      |     |       |           |
| SERVICE |       |        |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
| Deep    | 2.3   | I ≤    | N/S | 1 Hz | 0.  | Rec.  | None      |
| Space   | GHz   | --222  |     |      | 001 | ITU-R |           |
| R       |       | dBW    |     |      |     |       |           |
| esearch |       |        |     |      |     | SA    |           |
|         |       |        |     |      |     | .1157 |           |
| Earth   |       |        |     |      |     |       |           |
| S       |       |        |     |      |     |       |           |
| tations |       |        |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
|         | 8.4   | I ≤    | N/S |      |     |       |           |
|         | GHz   | --220  |     |      |     |       |           |
|         |       | dBW    |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
|         | 13.0  | I ≤    | N/S |      |     |       |           |
|         | GHz   | --220  |     |      |     |       |           |
|         |       | dBW    |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
|         | 32.0  | I ≤    | N/S |      |     |       |           |
|         | GHz   | --216  |     |      |     |       |           |
|         |       | dBW    |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
| Deep    | 2.1   | I ≤    | N/S | 20   | 0.  | Rec.  | None      |
| Space   | GHz   | --191  |     | Hz   | 001 | ITU-R |           |
| R       |       | dBW    |     |      |     |       |           |
| esearch |       |        |     |      |     | SA    |           |
|         |       |        |     |      |     | .1157 |           |
| Space   |       |        |     |      |     |       |           |
| S       |       |        |     |      |     |       |           |
| tations |       |        |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
|         | 7.2   | I ≤    | N/S |      |     |       |           |
|         | GHz   | --189  |     |      |     |       |           |
|         |       | dBW    |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
|         | 17.0  | I ≤    | N/S |      |     |       |           |
|         | GHz   | --186  |     |      |     |       |           |
|         |       | dBW    |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
|         | 34.5  | I ≤    | N/S |      |     |       |           |
|         | GHz   | --184  |     |      |     |       |           |
|         |       | dBW    |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
| Near    | 1-20  | I ≤    | N/S | 1 Hz | 0.  | Rec.  | I         |
| Earth   | GHz   | --216  |     |      | 001 | ITU-R | increases |
|         |       | dBW    |     |      | Man |       | 20 dB per |
| R       |       |        |     |      | ned | SA    | d         |
| esearch |       |        |     |      |     | .609I | ecreasing |
|         |       |        |     |      | 0.1 |       | frequency |
| Earth   |       |        |     |      | Un- |       | decade    |
| S       |       |        |     |      | man |       | below 1   |
| tations |       |        |     |      | ned |       | GHz       |
+---------+-------+--------+-----+------+-----+-------+-----------+
|         | Below | See    | N/S |      |     |       |           |
|         | 1 GHz | co     |     |      |     |       |           |
|         |       | mments |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+
| Near    | 100   | I ≤    | N/S | 1    | 0.1 | Rec.  | None      |
| Earth   | MHz-  | --177  |     | kHz  |     | ITU-R |           |
| Re      |       | dBW    |     |      |     |       |           |
| search\ | 30    |        |     |      |     | S     |           |
| Space   | GHz   |        |     |      |     | A.609 |           |
| S       |       |        |     |      |     |       |           |
| tations |       |        |     |      |     |       |           |
+---------+-------+--------+-----+------+-----+-------+-----------+

^i^ Unless otherwise indicated, IPC represents maximum allowable power
density at the receiver terminals.

+---------+----------+--------+-----+------+-----+-------+---------+
| S       | F        | Interf |     | R    | \%  | S     | **Com   |
| ervices | requency | erence |     | efer |     | ource | ments** |
|         |          | Prot   |     | ence | T   | Doc   |         |
| Systems | Bands    | ection |     | BW   | ime | ument |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         |          | CW &   | Pu  |      |     |       |         |
|         |          | Noi    | lse |      |     |       |         |
|         |          | selike |     |      |     |       |         |
|         |          |        | Ot  |      |     |       |         |
|         |          |        | her |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
| Data    | 2.0      | I ≤    | N/S | 1    | 0.1 | Rec.  | None    |
| Relay   | 25-2.110 | --181  |     | kHz  |     | ITU-R |         |
|         | GHz      | dBW    |     |      |     |       |         |
| Sa      |          |        |     |      |     | SA    |         |
| tellite |          |        |     |      |     | .1155 |         |
| Forward |          |        |     |      |     |       |         |
|         |          |        |     |      |     |       |         |
| Inte    |          |        |     |      |     |       |         |
| r-Orbit |          |        |     |      |     |       |         |
| Link    |          |        |     |      |     |       |         |
|         |          |        |     |      |     |       |         |
| User    |          |        |     |      |     |       |         |
| Spa     |          |        |     |      |     |       |         |
| cecraft |          |        |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         | 1        | I ≤    | N/S |      |     |       |         |
|         | 3.5-13.8 | --178  |     |      |     |       |         |
|         | GHz      | dBW    |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         | 22.      | I ≤    | N/S |      |     |       |         |
|         | 55-23.55 | --178  |     |      |     |       |         |
|         | GHz      | dBW    |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
| Data    | 2.2      | I ≤    | N/S | 1    | 0.1 | Rec.  | None    |
| Relay   | 00-2.290 | --181  |     | kHz  |     | ITU-R |         |
| Sa      | GHz      | dBW    |     |      |     |       |         |
| tellite |          |        |     |      |     | SA    |         |
| Return  |          |        |     |      |     | .1155 |         |
| In      |          |        |     |      |     |       |         |
| ter-Orb |          |        |     |      |     |       |         |
| it-Link |          |        |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         | 14.      | I ≤    | N/S |      |     |       |         |
|         | 89-15.18 | --178  |     |      |     |       |         |
|         | GHz      | dBW    |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         | 25       | I ≤    | N/S |      |     |       |         |
|         | .25-27.5 | --178  |     |      |     |       |         |
|         | GHz      | dBW    |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
| Data    | 14.      | I ≤    | N/S | 1    | 0.1 | Rec.  | None    |
| Relay   | 35-15.35 | --167  |     | kHz  |     | ITU-R |         |
| Sa      | GHz      | dBW    |     |      |     |       |         |
| tellite |          |        |     |      |     | SA    |         |
|         |          |        |     |      |     | .1155 |         |
| Forward |          |        |     |      |     |       |         |
| Feeder  |          |        |     |      |     |       |         |
| Link    |          |        |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         | 2        | I ≤    | N/S |      |     |       |         |
|         | 7.0-30.0 | --169  |     |      |     |       |         |
|         | GHz      | dBW    |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
| Data    | 10.      | I ≤    | N/S | 1    | 0.1 | Rec.  | None    |
| Relay   | 81-10.86 | --176  |     | kHz  |     | ITU-R |         |
|         | GHz      | dBW    |     |      |     |       |         |
| Sa      |          |        |     |      |     | SA    |         |
| tellite |          |        |     |      |     | .1155 |         |
| Return  |          |        |     |      |     |       |         |
| Feeder  |          |        |     |      |     |       |         |
| Link    |          |        |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         | 13       | I ≤    | N/S |      |     |       |         |
|         | .4-14.05 | --176  |     |      |     |       |         |
|         | GHz      | dBW    |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
|         | 1        | I ≤    | N/S |      |     |       |         |
|         | 7.2-21.2 | --172  |     |      |     |       |         |
|         | GHz      | dBW    |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
| Space   | 37-38    | I ≤    | N/S | 1 Hz | 0.1 | Rec.  | None    |
| R       | GHz      | --217  |     |      | Un- | ITU-R |         |
| esearch |          | dBW    |     |      | man |       |         |
|         |          |        |     |      | ned | SA    |         |
| Earth   |          |        |     |      |     | .1396 |         |
| Station |          |        |     |      | 0.  |       |         |
|         |          |        |     |      | 001 |       |         |
|         |          |        |     |      | Man |       |         |
|         |          |        |     |      | ned |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+
| Space   | 40-40.5  | I ≤    | N/S | 20   | 0.1 | Rec.  | None    |
| R       | GHz      | --193  |     | Hz   |     | ITU-R |         |
| esearch |          | dBW    |     |      |     |       |         |
|         |          |        |     |      |     | SA    |         |
| Space   |          |        |     |      |     | 1396  |         |
| Station |          |        |     |      |     |       |         |
+---------+----------+--------+-----+------+-----+-------+---------+

+---------+---------+---------+-----+------+----+-------+----------+
| S       | Fr      | Inter   |     | R    | \% | S     | Comments |
| ervices | equency | ference |     | efer |    | ource |          |
|         |         | Pro     |     | ence | Ti | Doc   |          |
| Systems | Bands   | tection |     | BW   | me | ument |          |
+---------+---------+---------+-----+------+----+-------+----------+
|         |         | CW &    | Pu  |      |    |       |          |
|         |         | No      | lse |      |    |       |          |
|         |         | iselike |     |      |    |       |          |
|         |         |         | Ot  |      |    |       |          |
|         |         |         | her |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
| SPACE   |         |         |     |      |    |       |          |
| OPE     |         |         |     |      |    |       |          |
| RATIONS |         |         |     |      |    |       |          |
| SERVICE |         |         |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
| Earth   | 1-30    | I ≤     | N/S | 1    | 1  | Rec.  | I        |
| Station | GHz     | -184    |     | kHz  |    | ITU-R | i        |
|         |         | dBW     |     |      |    |       | ncreases |
|         |         |         |     |      |    | SA    | 20 dB    |
|         |         |         |     |      |    | .1263 | per      |
|         |         |         |     |      |    |       | de       |
|         |         |         |     |      |    |       | creasing |
|         |         |         |     |      |    |       | f        |
|         |         |         |     |      |    |       | requency |
|         |         |         |     |      |    |       | decade   |
|         |         |         |     |      |    |       |          |
|         |         |         |     |      |    |       | below 1  |
|         |         |         |     |      |    |       | GHz      |
+---------+---------+---------+-----+------+----+-------+----------+
|         | 0.1-1   | See     | N/S |      |    |       |          |
|         | GHz     | C       |     |      |    |       |          |
|         |         | omments |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
| Space   | 100     | S/I ≥   | N/S | 1    | 1  | Rec.  | None     |
| Station | MHz-30  | 20 dB   |     | kHz  |    | ITU-R |          |
|         | GHz     |         |     |      |    |       |          |
|         |         |         |     |      |    | SA.   |          |
|         |         |         |     |      |    | 363-5 |          |
+---------+---------+---------+-----+------+----+-------+----------+
| METEORO |         |         |     |      |    |       |          |
| LOGICAL |         |         |     |      |    |       |          |
| AIDS    |         |         |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
| Radio   | 1669    | I ≤     | N/S | 1.3  | 0. | Rec.  | None     |
| Di      | .4-1700 | --135.3 |     | MHz  | 02 | ITU-R |          |
| rection | MHz     | dBW     |     |      |    |       |          |
|         |         |         |     |      |    | SA    |          |
| Finding |         |         |     |      |    | .1263 |          |
|         |         |         |     |      |    |       |          |
| Rad     |         |         |     |      |    |       |          |
| iosonde |         |         |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
|         | 1669    | I ≤     | N/S |      | 1. |       |          |
|         | .4-1700 | --148.5 |     |      | 25 |       |          |
|         | MHz     | dBW     |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
|         | 1669    | I ≤     | N/S |      | 20 |       |          |
|         | .4-1700 | --149.4 |     |      |    |       |          |
|         | MHz     | dBW     |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
| NAVAID  | 400     | I ≤     | N/S | 300  | 0. | Rec.  | None     |
|         | .15-406 | --140.6 |     | kHz  | 02 | ITU-R |          |
| Rad     | MHz     | dBW     |     |      |    |       |          |
| iosonde |         |         |     |      |    | SA    |          |
|         |         |         |     |      |    | .1263 |          |
| Dire    |         |         |     |      |    |       |          |
| ctional |         |         |     |      |    |       |          |
| R       |         |         |     |      |    |       |          |
| eceiver |         |         |     |      |    |       |          |
|         |         |         |     |      |    |       |          |
| Antenna |         |         |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
|         | 400     | I ≤     | N/S |      | 1. |       |          |
|         | .15-406 | --149.6 |     |      | 25 |       |          |
|         | MHz     | dBW     |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
|         | 400     | I ≤     | N/S |      | 20 |       |          |
|         | .15-406 | --154.9 |     |      |    |       |          |
|         | MHz     | dBW     |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
| Om      | 400     | I ≤     | N/S | 300  | 0. | Rec.  | None     |
| ni-Dire | .15-406 | --141.9 |     | kHz  | 02 | ITU-R |          |
| ctional | MHz     | dBW     |     |      |    |       |          |
| R       |         |         |     |      |    | SA    |          |
| eceiver |         |         |     |      |    | .1263 |          |
| Antenna |         |         |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
|         | 400     | I ≤     | N/S |      | 1. |       |          |
|         | .15-406 | --154.4 |     |      | 25 |       |          |
|         | MHz     | dBW     |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+
|         | 400     | I ≤     | N/S |      | 20 |       |          |
|         | .15-406 | --156.1 |     |      |    |       |          |
|         | MHz     | dBW     |     |      |    |       |          |
+---------+---------+---------+-----+------+----+-------+----------+

+---------+---------+-------+------+------+------+-------+----------+
| S       | Fr      | In    |      | R    | \%   | S     | Comments |
| ervices | equency | terfe |      | efer |      | ource |          |
| Systems | Bands   | rence |      | ence | Time | Doc   |          |
|         |         | Prote |      | BW   |      | ument |          |
|         |         | ction |      |      |      |       |          |
+=========+=========+=======+======+======+======+=======+==========+
|         |         | CW &  | P    |      |      |       |          |
|         |         | Nois  | ulse |      |      |       |          |
|         |         | elike |      |      |      |       |          |
|         |         |       | O    |      |      |       |          |
|         |         |       | ther |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+
| A       | 400     | I ≤   | N/S  | 20   | 0.02 | Rec.  | None     |
| irborne | .15-406 | --    |      | kHz  |      | ITU-R |          |
| Dr      | MHz     | 153.3 |      |      |      |       |          |
| opsonde |         | dBW   |      |      |      | SA    |          |
|         |         |       |      |      |      | .1263 |          |
+---------+---------+-------+------+------+------+-------+----------+
|         | 400     | I ≤   | N/S  |      | 0.03 |       |          |
|         | .15-406 | --    |      |      |      |       |          |
|         | MHz     | 161.5 |      |      |      |       |          |
|         |         | dBW   |      |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+
|         | 400     | I ≤   | N/S  |      | 20   |       |          |
|         | .15-406 | --    |      |      |      |       |          |
|         | MHz     | 167.1 |      |      |      |       |          |
|         |         | dBW   |      |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+
| Rock    | 400     | I     | N/S  | 3    | 0.02 | Rec.  | None     |
| etsonde | .15-406 | ≤--   |      | MHz  |      | ITU-R |          |
|         | MHz     | 124.9 |      |      |      |       |          |
|         |         | dBW   |      |      |      | SA    |          |
|         |         |       |      |      |      | .1263 |          |
+---------+---------+-------+------+------+------+-------+----------+
|         | 400     | I ≤   | N/S  |      | 0.03 |       |          |
|         | .15-406 | --    |      |      |      |       |          |
|         | MHz     | 125.5 |      |      |      |       |          |
|         |         | dBW   |      |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+
|         | 400     | I ≤   | N/S  |      | 20   |       |          |
|         | .15-406 | --    |      |      |      |       |          |
|         | MHz     | 134.7 |      |      |      |       |          |
|         |         | dBW   |      |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+
| EARTH   |         |       |      |      |      |       |          |
| EXPL    |         |       |      |      |      |       |          |
| ORATION |         |       |      |      |      |       |          |
| AND     |         |       |      |      |      |       |          |
| METEORO |         |       |      |      |      |       |          |
| LOGICAL |         |       |      |      |      |       |          |
| SA      |         |       |      |      |      |       |          |
| TELLITE |         |       |      |      |      |       |          |
| S       |         |       |      |      |      |       |          |
| ERVICES |         |       |      |      |      |       |          |
| (EES/   |         |       |      |      |      |       |          |
| METSAT) |         |       |      |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+
| Command | 1-10    | I ≤   | N/S  | 1    | 1    | Rec.  | I        |
| Data    | GHz     | --154 |      | MHz  |      | ITU-R | i        |
|         |         | dBW   |      |      |      |       | ncreases |
| Earth   |         |       |      |      |      | S     | 20 dB    |
| Station |         |       |      |      |      | A.514 | per      |
|         |         |       |      |      |      |       | de       |
|         |         |       |      |      |      |       | creasing |
|         |         |       |      |      |      |       | f        |
|         |         |       |      |      |      |       | requency |
|         |         |       |      |      |      |       | decade   |
|         |         |       |      |      |      |       | below 1  |
|         |         |       |      |      |      |       | GHz      |
+---------+---------+-------+------+------+------+-------+----------+
|         | Below 1 | See   | N/S  |      |      |       |          |
|         | GHz     | Com   |      |      |      |       |          |
|         |         | ments |      |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+
| Command | 0.3-10  | I ≤   | N/S  | 1    | 0.1  | Rec.  | I        |
| Data    | GHz     | --161 |      | kHz  |      | ITU-R | i        |
|         |         | dBW   |      |      |      |       | ncreases |
| Near    |         |       |      |      |      | S     | 20 dB    |
| Earth   |         |       |      |      |      | A.514 | per      |
|         |         |       |      |      |      |       | de       |
| Spa     |         |       |      |      |      |       | creasing |
| cecraft |         |       |      |      |      |       | f        |
|         |         |       |      |      |      |       | requency |
|         |         |       |      |      |      |       | decade   |
|         |         |       |      |      |      |       | below    |
|         |         |       |      |      |      |       | 0.3 GHz. |
+---------+---------+-------+------+------+------+-------+----------+
|         | Below   | See   | N/S  |      |      |       |          |
|         | 0.3 GHz | com   |      |      |      |       |          |
|         |         | ments |      |      |      |       |          |
+---------+---------+-------+------+------+------+-------+----------+

+---------+---------+-------+------+-------+-----+-------+--------+
| S       | Fr      | In    |      | Refe  | \%  | S     | Co     |
| ervices | equency | terfe |      | rence |     | ource | mments |
|         |         | rence |      |       | T   |       |        |
| Systems | Bands   | Prote |      | BW    | ime | Doc   |        |
|         |         | ction |      |       |     | ument |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         |         | CW &  | P    |       |     |       |        |
|         |         | Nois  | ulse |       |     |       |        |
|         |         | elike |      |       |     |       |        |
|         |         |       | O    |       |     |       |        |
|         |         |       | ther |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Space   | 137-138 | I ≤   | N/S  | 50    | 20  | Rec.  | Analog |
| to      | MHz     | --151 |      | kHz   |     | ITU-R | re     |
| Earth   |         | dBW   |      |       |     |       | ceiver |
| Data    |         |       |      |       |     | SA    |        |
|         |         |       |      |       |     | .1026 | 2 dBic |
| Earth   |         |       |      |       |     |       | a      |
| S       |         |       |      |       |     |       | ntenna |
| tations |         |       |      |       |     |       | ga     |
|         |         |       |      |       |     |       | in^ii^ |
| Direct  |         |       |      |       |     |       |        |
| Data    |         |       |      |       |     |       |        |
| Readout |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 137-138 | I ≤   | N/S  |       | 0.  |       |        |
|         | MHz     | --145 |      |       | 025 |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 137-138 | I ≤   | N/S  | 150   | 20  |       | D      |
|         | MHz     | --141 |      | kHz   |     |       | igital |
|         |         | dBW   |      |       |     |       | re     |
|         |         |       |      |       |     |       | ceiver |
|         |         |       |      |       |     |       | 10     |
|         |         |       |      |       |     |       | dBic   |
|         |         |       |      |       |     |       | a      |
|         |         |       |      |       |     |       | ntenna |
|         |         |       |      |       |     |       | gain   |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 137-138 | I ≤   | N/S  |       | 0   |       |        |
|         | MHz     | --133 |      |       | .25 |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 137-138 | I ≤   | N/S  |       | 20  |       | D      |
|         | MHz     | --142 |      |       |     |       | igital |
|         |         | dBW   |      |       |     |       | re     |
|         |         |       |      |       |     |       | ceiver |
|         |         |       |      |       |     |       | 2 dBic |
|         |         |       |      |       |     |       | a      |
|         |         |       |      |       |     |       | ntenna |
|         |         |       |      |       |     |       | gain   |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 137-138 | I ≤   | N/S  |       | 0.  |       |        |
|         | MHz     | --136 |      |       | 025 |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 400.15  | I ≤   | N/S  | 177.5 | 20  |       | D      |
|         | -401.00 | --158 |      | kHz   |     |       | igital |
|         | MHz     | dBW   |      |       |     |       | re     |
|         |         |       |      |       |     |       | ceiver |
|         |         |       |      |       |     |       | 0 dBic |
|         |         |       |      |       |     |       | a      |
|         |         |       |      |       |     |       | ntenna |
|         |         |       |      |       |     |       | gain   |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 400.15  | I ≤   | N/S  |       | 0.  |       |        |
|         | -401.00 | --147 |      |       | 025 |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  | 2668  | 20  |       | 29.8   |
|         | 96-1710 | --147 |      | kHz   |     |       | dBic   |
|         | MHz     | dBW   |      |       |     |       |        |
|         |         |       |      |       |     |       | a      |
|         |         |       |      |       |     |       | ntenna |
|         |         |       |      |       |     |       | gain   |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  |       | 0.  |       |        |
|         | 96-1710 | --138 |      |       | 025 |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 80      | I ≤   | N/S  | 40    | 20  |       | 42.5   |
|         | 25-8400 | --136 |      | MHz   |     |       | dBic   |
|         | MHz     | dBW   |      |       |     |       |        |
|         |         |       |      |       |     |       | a      |
|         |         |       |      |       |     |       | ntenna |
|         |         |       |      |       |     |       | gain   |
|         |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       | System |
|         |         |       |      |       |     |       | A      |
+---------+---------+-------+------+-------+-----+-------+--------+

^ii^ For analog and digital receivers with 2 dBic antenna gain, the
interfering signal power levels (dBW) in the reference bandwidths are
specified for reception at elevation angles greater than or equal to
25^o^.

+---------+---------+--------+------+-------+-----+-------+--------+
| S       | Fr      | Interf |      | Refe  | \%  | S     | Co     |
| ervices | equency | erence |      | rence |     | ource | mments |
|         |         | Prot   |      |       | T   |       |        |
| Systems | Bands   | ection |      | BW    | ime | Doc   |        |
|         |         |        |      |       |     | ument |        |
+---------+---------+--------+------+-------+-----+-------+--------+
|         |         | CW &   | P    |       |     |       |        |
|         |         | Noi    | ulse |       |     |       |        |
|         |         | selike |      |       |     |       |        |
|         |         |        | O    |       |     |       |        |
|         |         |        | ther |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
| Space   | 80      | I ≤    | N/S  | 40    | 0   | Rec.  | 56.3   |
| to      | 25-8400 | --125  |      | MHz   | .25 | ITU-R | dBic   |
| Earth   | MHz     | dBW    |      |       |     |       | a      |
| Data    |         |        |      |       |     | SA.   | ntenna |
|         |         |        |      |       |     | 1026  |        |
| Earth   |         |        |      |       |     |       | System |
| S       |         |        |      |       |     |       | B      |
| tations |         |        |      |       |     |       |        |
|         |         |        |      |       |     |       |        |
| Direct  |         |        |      |       |     |       |        |
| Data    |         |        |      |       |     |       |        |
| Readout |         |        |      |       |     |       |        |
|         |         |        |      |       |     |       |        |
| (cont.) |         |        |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 80      | I ≤    | N/S  |       | 20  |       |        |
|         | 25-8400 | --125  |      |       |     |       |        |
|         | MHz     | dBW    |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 80      | I ≤    | N/S  |       | 0   |       |        |
|         | 25-8400 | --116  |      |       | .25 |       |        |
|         | MHz     | dBW    |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 25      | I ≤    | N/S  | 10    | 20  |       | 42.5   |
|         | .5-27.0 | --137  |      | MHz   |     |       | dBic   |
|         | GHz     | dBW    |      |       |     |       |        |
|         |         |        |      |       |     |       | a      |
|         |         |        |      |       |     |       | ntenna |
|         |         |        |      |       |     |       | gain   |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 25      | I ≤    | N/S  |       | 0   |       |        |
|         | .5-27.0 | --120  |      |       | .25 |       |        |
|         | GHz     | dBW    |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
| Hig     | 25      | I ≤    | N/S  | 10    | 20  | Rec.  | 42.5   |
| h-speed | .5-27.0 | --136  |      | MHz   |     | ITU-R | dBic   |
| Direct  | GHz     | dBW    |      |       |     |       |        |
|         |         |        |      |       |     | SA.   | a      |
| Data    |         |        |      |       |     | 1026  | ntenna |
| Readout |         |        |      |       |     |       | gain   |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 25      | I ≤    | N/S  |       | 0   |       |        |
|         | .5-27.0 | --122  |      |       | .25 |       |        |
|         | GHz     | dBW    |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
| R       | 16      | I ≤    | N/S  | 5334  | 20  | Rec.  | 46.8   |
| ecorded | 96-1710 | --128  |      | kHz   |     | ITU-R | dBic   |
| Data    | MHz     | dBW    |      |       |     |       |        |
|         |         |        |      |       |     | SA.   | a      |
| Acqu    |         |        |      |       |     | 1026  | ntenna |
| isition |         |        |      |       |     |       | gain   |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 16      | I ≤    | N/S  |       | 0.  |       |        |
|         | 96-1710 | --121  |      |       | 025 |       |        |
|         | MHz     | dBW    |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 77      | I ≤    | N/S  | 100   | 20  |       | 54.0   |
|         | 50-7850 | --128  |      | MHz   |     |       | dBic   |
|         | MHz     | dBW    |      |       |     |       |        |
|         |         |        |      |       |     |       | a      |
|         |         |        |      |       |     |       | ntenna |
|         |         |        |      |       |     |       | gain   |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 77      | I ≤    | N/S  |       | 0.  |       |        |
|         | 50-7850 | --115  |      |       | 025 |       |        |
|         | MHz     | dBW    |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 80      | I ≤    | N/S  |       | 20  |       | 55.2   |
|         | 25-8400 | --131  |      |       |     |       | dBic   |
|         | MHz     | dBW    |      |       |     |       |        |
|         |         |        |      |       |     |       | a      |
|         |         |        |      |       |     |       | ntenna |
|         |         |        |      |       |     |       | gain   |
+---------+---------+--------+------+-------+-----+-------+--------+
|         | 80      | I ≤    | N/S  |       | 0.  |       |        |
|         | 25-8400 | --117  |      |       | 025 |       |        |
|         | MHz     | dBW    |      |       |     |       |        |
+---------+---------+--------+------+-------+-----+-------+--------+

+---------+---------+-------+------+-------+-----+-------+--------+
| S       | Fr      | In    |      | Refe  | \%  | S     | Co     |
| ervices | equency | terfe |      | rence |     | ource | mments |
|         |         | rence |      |       | T   |       |        |
| Systems | Bands   | Prote |      | BW    | ime | Doc   |        |
|         |         | ction |      |       |     | ument |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         |         | CW &  | P    |       |     |       |        |
|         |         | Nois  | ulse |       |     |       |        |
|         |         | elike |      |       |     |       |        |
|         |         |       | O    |       |     |       |        |
|         |         |       | ther |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| R       | 25      | I ≤   | N/S  | 10    | 20  | Rec.  | 55.2   |
| ecorded | .5-27.0 | --134 |      | MHz   |     | ITU-R | dBic   |
| Data    | GHz     | dBW   |      |       |     |       |        |
|         |         |       |      |       |     | SA.   | a      |
| Acqu    |         |       |      |       |     | 1026  | ntenna |
| isition |         |       |      |       |     |       | gain   |
|         |         |       |      |       |     |       |        |
| (cont.) |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 25      | I ≤   | N/S  |       | 0   |       |        |
|         | .5-27.0 | --118 |      |       | .25 |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Direct  | 16      | I ≤   | N/S  | 2.6   | 20  | Rec.  | High   |
| Data    | 70-1710 | --    |      | MHz   |     | ITU-R | gain   |
| Readout | MHz     | 153.8 |      |       |     |       | a      |
|         |         | dBW   |      |       |     | SA.   | ntenna |
| Space-t |         |       |      |       |     | 1160  |        |
| o-earth |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  |       | 0.  |       |        |
|         | 70-1710 | --    |      |       | 025 |       |        |
|         | MHz     | 148.6 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 25      | I ≤   | N/S  | 10    | 20  |       |        |
|         | .5-27.0 | --    |      | MHz   |     |       |        |
|         | GHz     | 131.7 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 25      | I ≤   | N/S  |       | 0   |       |        |
|         | .5-27.0 | --    |      |       | .25 |       |        |
|         | GHz     | 116.3 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Data    | 16      | I ≤   | N/S  | 4 kHz | 20  | Rec.  | Low    |
| Dissem  | 70-1710 | --    |      |       |     | ITU-R | gain   |
| ination | MHz     | 167.5 |      |       |     |       | a      |
|         |         | dBW   |      |       |     | SA.   | ntenna |
| Space-t |         |       |      |       |     | 1160  |        |
| o-earth |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  |       | 0.  |       |        |
|         | 70-1710 | --    |      |       | 025 |       |        |
|         | MHz     | 160.4 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  | 2.11  | 20  |       | High   |
|         | 70-1710 | --    |      | MHz   |     |       | gain   |
|         | MHz     | 153.4 |      |       |     |       | a      |
|         |         | dBW   |      |       |     |       | ntenna |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  |       | 0.  |       |        |
|         | 70-1710 | --    |      |       | 025 |       |        |
|         | MHz     | 148.1 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Command | 20      | I ≤   | N/S  | 2.11  | 20  | Rec.  | High   |
| Data    | 25-2110 | --    |      | MHz   |     | ITU-R | reso   |
|         | MHz     | 136.7 |      |       |     |       | lution |
| Acqu    |         | dBW   |      |       |     | SA.   |        |
| isition |         |       |      |       |     | 1160  | data   |
|         |         |       |      |       |     |       |        |
| (CDA)   |         |       |      |       |     |       |        |
| Station |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| Earth-t |         |       |      |       |     |       |        |
| o-space |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 20      | I ≤   | N/S  |       | 0.  |       |        |
|         | 25-2110 | --    |      |       | 025 |       |        |
|         | MHz     | 133.4 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+

+---------+---------+-------+------+-------+-----+-------+--------+
| S       | Fr      | In    |      | Refe  | \%  | S     | Co     |
| ervices | equency | terfe |      | rence |     | ource | mments |
|         |         | rence |      |       | T   |       |        |
| Systems | Bands   | Prote |      | BW    | ime | Doc   |        |
|         |         | ction |      |       |     | ument |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         |         | CW &  | P    |       |     |       |        |
|         |         | Nois  | ulse |       |     |       |        |
|         |         | elike |      |       |     |       |        |
|         |         |       | O    |       |     |       |        |
|         |         |       | ther |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Command | 20      | I ≤   | N/S  | 4 kHZ | 20  | Rec.  | WEFAX  |
| Data    | 25-2110 | --    |      |       |     | ITU-R | data   |
|         | MHz     | 147.8 |      |       |     |       |        |
| Acqu    |         | dBW   |      |       |     | SA.   |        |
| isition |         |       |      |       |     | 1160  |        |
|         |         |       |      |       |     |       |        |
| (CDA)   |         |       |      |       |     |       |        |
| Station |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| Earth-t |         |       |      |       |     |       |        |
| o-space |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| (cont.) |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 20      | I ≤   | N/S  |       | 0.  |       |        |
|         | 25-2110 | --    |      |       | 025 |       |        |
|         | MHz     | 140.7 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Service | 401-403 | I ≤-- | N/S  | 1.6   | 20  | Rec.  | Lo     |
| Data    | MHz     | 178.8 |      | kHZ   |     | ITU-R | w-gain |
| Col     |         | dBW   |      |       |     |       | a      |
| lection |         |       |      |       |     | SA    | ntenna |
| Links   |         |       |      |       |     | .1160 |        |
| Non-GSO |         |       |      |       |     |       |        |
| Space   |         |       |      |       |     |       |        |
| Station |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 401-403 | I ≤   | N/S  |       | 0.1 |       |        |
|         | MHz     | --    |      |       |     |       |        |
|         |         | 174.7 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Service | 401-403 | I ≤   | N/S  | 100   | 20  | Rec.  |        |
| Data    | MHz     | --    |      | Hz    |     | I     |        |
| Col     |         | 187.4 |      |       |     | TU-R. |        |
| lection |         | dBW   |      |       |     |       |        |
| Links   |         |       |      |       |     | SA    |        |
| GSO     |         |       |      |       |     | .1163 |        |
| Space   |         |       |      |       |     |       |        |
| Station |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 401-403 | I ≤   | N/S  | 4 kHz | 0.1 |       |        |
|         | MHz     | --    |      |       |     |       |        |
|         |         | 173.4 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Command | 20      | I ≤   | N/S  | 100   | 20  | Rec.  | None   |
| and     | 25-2110 | --    |      | Hz    |     | ITU-R |        |
|         | MHz     | 188.9 |      |       |     |       |        |
| Data    |         | dBW   |      |       |     | SA    |        |
| Acqu    |         |       |      |       |     | .1163 |        |
| isition |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| Station |         |       |      |       |     |       |        |
| (CDA)   |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 20      | I ≤   | N/S  |       | 0.  |       |        |
|         | 25-2110 | --    |      |       | 025 |       |        |
|         | MHz     | 183.7 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Service | 137-138 | I ≤   | N/S  | 8.32  | 20  | Rec.  | None   |
| Links   | MHz     | --    |      | kHz   |     | ITU-R |        |
|         |         | 158.3 |      |       |     |       |        |
| Earth   |         | dBW   |      |       |     | SA    |        |
| Station |         |       |      |       |     | .1163 |        |
|         |         |       |      |       |     |       |        |
| Non-GSO |         |       |      |       |     |       |        |
| Data    |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| Col     |         |       |      |       |     |       |        |
| lection |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| GSO     |         |       |      |       |     |       |        |
| Data    |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| Col     |         |       |      |       |     |       |        |
| lection |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| CDA     |         |       |      |       |     |       |        |
| Station |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 137-138 | I ≤   | N/S  |       | 0.1 |       |        |
|         | MHz     | --    |      |       |     |       |        |
|         |         | 151.1 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  | 100   | 20  |       |        |
|         | 70-1690 | --    |      | Hz    |     |       |        |
|         | MHz     | 194.0 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 16      | I ≤   | N/S  |       | 0.  |       |        |
|         | 70-1690 | --    |      |       | 025 |       |        |
|         | MHz     | 181.5 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+

+---------+---------+-------+------+-------+------+-------+-------+
| S       | Fr      | In    |      | Refe  | \%   | S     | Com   |
| ervices | equency | terfe |      | rence |      | ource | ments |
|         |         | rence |      |       | Time |       |       |
| Systems | Bands   | Prote |      | BW    |      | Doc   |       |
|         |         | ction |      |       |      | ument |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         |         | CW    | P    |       |      |       |       |
|         |         | and   | ulse |       |      |       |       |
|         |         | Nois  |      |       |      |       |       |
|         |         | elike | O    |       |      |       |       |
|         |         |       | ther |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
| GSO     | 460-470 | I ≤   | N/S  | 100   | 20   | Rec   | None  |
| Data    | MHz     | --    |      | Hz    |      | I     |       |
|         |         | 187.3 |      |       |      | TU-R. |       |
| P       |         | dBW   |      |       |      |       |       |
| latform |         |       |      |       |      | SA    |       |
| Col     |         |       |      |       |      | .1163 |       |
| lection |         |       |      |       |      |       |       |
| Inte    |         |       |      |       |      |       |       |
| gration |         |       |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | 460-470 | I ≤   | N/S  |       | 0.1  |       |       |
|         | MHz     | --    |      |       |      |       |       |
|         |         | 182.1 |      |       |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
| P       | Near    | I ≤   | N/S  | 27    | See  | Rec.  | None  |
| assive\ | 1.4 GHz | --171 |      | MHz   | F    | ITU-R |       |
| Sensor  |         | dBW   |      |       | ootn |       |       |
|         |         |       |      |       | ote^ | SA.   |       |
|         |         |       |      |       | iii^ | 1029  |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | Near    | I ≤   | N/S  | 10    |      |       |       |
|         | 2.7 GHz | --174 |      | MHz   |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | Near 4  | I ≤   | N/S  | 100   |      |       |       |
|         | GHz     | --161 |      | MHz   |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | Near 6  | I ≤   | N/S  |       |      |       |       |
|         | GHz     | --164 |      |       |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | Near 11 | I ≤   | N/S  | 20    |      |       |       |
|         | GHz     | --163 |      | MHz   |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | Near 15 | I ≤   | N/S  | 50    |      |       |       |
|         | GHz     | --166 |      | MHz   |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | Near 18 | I ≤   | N/S  | 100   |      |       |       |
|         | GHz     | --155 |      | MHz   |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | Near 21 | I ≤   | N/S  |       |      |       |       |
|         | GHz     | --163 |      |       |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+
|         | 22.235  | I ≤   | N/S  |       |      |       |       |
|         | GHz     | --160 |      |       |      |       |       |
|         |         | dBW   |      |       |      |       |       |
+---------+---------+-------+------+-------+------+-------+-------+

^iii^ In shared bands, the specified interfering signal power levels may
be exceeded for no more than 5% of all measurement cells where data loss
occurs randomly and for no more than 1% where loss occurs
systematically. The specified interfering signal levels may be exceeded
for no more than 0.001% time for three dimensional measurements of
atmospheric temperature or gas concentration.

+---------+---------+-------+-----+------+------+-------+---------+
| S       | Fr      | In    |     | R    | \%   | S     | C       |
| ervices | equency | terfe |     | efer |      | ource | omments |
|         |         | rence |     | ence | Time |       |         |
| Systems | Bands   | Prote |     |      |      | Doc   |         |
|         |         | ction |     | BW   |      | ument |         |
+---------+---------+-------+-----+------+------+-------+---------+
|         |         | CW &  | Pu  |      |      |       |         |
|         |         | Nois  | lse |      |      |       |         |
|         |         | elike |     |      |      |       |         |
|         |         |       | Ot  |      |      |       |         |
|         |         |       | her |      |      |       |         |
+---------+---------+-------+-----+------+------+-------+---------+
| P       | Near 24 | I ≤   | N/S | 100  | See  | Rec.  | None    |
| assive\ | GHz     | --163 |     | MHz  | Foot | ITU-R |         |
| Sensor  |         | dBW   |     |      | note |       |         |
|         |         |       |     |      | ^iv^ | SA.   |         |
| (cont). |         |       |     |      |      | 1029  |         |
+---------+---------+-------+-----+------+------+-------+---------+
|         | Near 31 | I ≤   | N/S |      |      |       |         |
|         | GHz     | --163 |     |      |      |       |         |
|         |         | dBW   |     |      |      |       |         |
+---------+---------+-------+-----+------+------+-------+---------+
|         | Near 37 | I ≤   | N/S | 100  | See  | Rec.  | N/S     |
|         | GHz     | --156 |     | MHz  |      | ITU-R |         |
|         |         | dBW   |     |      | Foot |       |         |
|         |         |       |     |      | note | SA.   |         |
|         |         |       |     |      | ^iv^ | 1029  |         |
+---------+---------+-------+-----+------+------+-------+---------+
|         | 50      | I ≤   | N/S | 100  | N/S  | N/S   | ≤--166  |
|         | .2-50.4 | --161 |     | MHz  |      |       | dBW for |
|         | GHz     | dBW   |     |      |      |       | p       |
|         |         |       |     |      |      |       | ushboom |
|         |         |       |     |      |      |       | sensors |
+---------+---------+-------+-----+------+------+-------+---------+
|         | 52      | I ≤   | N/S |      |      |       |         |
|         | .6-59.0 | --161 |     |      |      |       |         |
|         | GHz     | dBW   |     |      |      |       |         |
+---------+---------+-------+-----+------+------+-------+---------+
|         | 60      | I ≤   | N/S |      |      |       |         |
|         | .3-61.3 | --161 |     |      |      |       |         |
|         | GHz     | dBW   |     |      |      |       |         |
+---------+---------+-------+-----+------+------+-------+---------+
|         | Near 90 | I ≤   | N/S | 200  | See  | Rec.  | None    |
|         | GHz     | --153 |     | MHz  | Foot | ITU-R |         |
|         |         | dBW   |     |      | note |       |         |
|         |         |       |     |      | ^iv^ | SA.   |         |
|         |         |       |     |      |      | 1029  |         |
+---------+---------+-------+-----+------+------+-------+---------+
|         | 100.49  | I ≤   | N/S | 200  |      | Rec.  | Several |
|         | -380.20 | --160 |     | MHz  |      | ITU-R | d       |
|         | GHz     | dBW   |     |      |      | SA.   | iscrete |
|         |         |       |     |      |      | 1029  | fr      |
|         |         |       |     |      |      |       | equency |
|         |         |       |     |      |      |       | bands   |
+---------+---------+-------+-----+------+------+-------+---------+
| Active  | Near    | I ≤   | N/S | 10   | N/S  | Rec.  | None    |
| Sensors | 400 MHz | --138 |     | MHz  |      | ITU-R |         |
|         |         | dBW   |     |      |      |       |         |
| Sy      |         |       |     |      |      | SA    |         |
| nthetic |         |       |     |      |      | .1166 |         |
| A       |         |       |     |      |      |       |         |
| perture |         |       |     |      |      |       |         |
|         |         |       |     |      |      |       |         |
| Radar   |         |       |     |      |      |       |         |
| (SAR)   |         |       |     |      |      |       |         |
+---------+---------+-------+-----+------+------+-------+---------+

^iv^ In shared bands, the specified interfering signal levels may be
exceeded for no more than 5% of all measurement cells where data loss
occurs randomly and for no more than 1% where loss occurs
systematically. The specified interfering signal levels can be exceeded
for no more than 0.001% time for three dimensional measurements of
atmospheric temperature or gas concentration.

+---------+---------+-------+------+-------+-----+-------+--------+
| Service | Fr      | In    |      | Refe  | \%  | S     | Co     |
|         | equency | terfe |      | rence |     | ource | mments |
| Systems |         | rence |      |       | T   |       |        |
|         | Bands   | Prote |      | BW    | ime | Doc   |        |
|         |         | ction |      |       |     | ument |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         |         | CW &  | P    |       |     |       |        |
|         |         | Nois  | ulse |       |     |       |        |
|         |         | elike |      |       |     |       |        |
|         |         |       | O    |       |     |       |        |
|         |         |       | ther |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Alt     | Near    | I ≤   | N/S  | 100   | N/S | Rec.  | None   |
| imeters | 5.3 GHz | --123 |      | MHz   |     | ITU-R |        |
|         |         | dBW   |      |       |     | SA    |        |
|         |         |       |      |       |     | .1166 |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 13      | I ≤   | N/S  | 320   |     |       |        |
|         | .0-14.0 | --119 |      | MHz   |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 35      | I ≤   | N/S  | 450   |     |       |        |
|         | .5-36.0 | --112 |      | MHz   |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Scatter | Near    | I ≤   | N/S  | 10    | N/S | Rec.  | None   |
| ometers | 5.3 GHz | --155 |      | kHz   |     | ITU-R |        |
|         |         | dBW   |      |       |     | SA    |        |
| Sp      |         |       |      |       |     | .1166 |        |
| ot-beam |         |       |      |       |     |       |        |
| antenna |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 13      | I ≤   | N/S  |       |     |       |        |
|         | .0-14.0 | --155 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 35      | I ≤   | N/S  |       |     |       |        |
|         | .5-36.0 | --158 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Precip  | 13      | I ≤   | N/S  | 600   | N/S | Rec.  | None   |
| itation | .0-14.0 | --150 |      | kHz   |     | ITU-R |        |
| Radars  | GHz     | dBW   |      |       |     | SA    |        |
|         |         |       |      |       |     | .1166 |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 35      | I ≤   | N/S  |       |     |       |        |
|         | .0-36.0 | --152 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Cloud   | 35      | I ≤   | N/S  | 300   | N/S | Rec.  | None   |
| Pr      | .5-36.0 | --155 |      | kHz   |     | ITU-R |        |
| ofiling | GHz     | dBW   |      |       |     | SA    |        |
| Radars  |         |       |      |       |     | .1166 |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 94-94.1 | I ≤   | N/S  |       |     |       |        |
|         | GHz     | --155 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+

+---------+---------+-------+------+-------+-----+-------+--------+
| S       | Fr      | In    |      | Refe  | \%  | S     | Co     |
| ervices | equency | terfe |      | rence |     | ource | mments |
|         |         | rence |      |       | T   |       |        |
| Systems | Bands   | Prote |      | BW    | ime | Doc   |        |
|         |         | ction |      |       |     | ument |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         |         | CW &  | P    |       |     |       |        |
|         |         | Nois  | ulse |       |     |       |        |
|         |         | elike |      |       |     |       |        |
|         |         |       | O    |       |     |       |        |
|         |         |       | ther |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| RADIO   |         |       |      |       |     |       |        |
| ASTRO   |         |       |      |       |     |       |        |
| NOMICAL |         |       |      |       |     |       |        |
| MEASU   |         |       |      |       |     |       |        |
| REMENTS |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Radio   | 13.3    | I ≤   | N/S  | 1 Hz  | N/S | Rec.  | None   |
| As      | 6-13.41 | --248 |      |       |     | ITU-R |        |
| tronomy | MHz     | dBW   |      |       |     |       |        |
|         |         |       |      |       |     | R     |        |
|         |         |       |      |       |     | A.769 |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 25.5    | I ≤   | N/S  |       |     |       |        |
|         | 5-26.70 | --249 |      |       |     |       |        |
|         | MH      | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 73      | I ≤   | N/S  |       |     |       |        |
|         | .0-74.6 | --258 |      |       |     |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 150.0   | I ≤   | N/S  |       |     |       |        |
|         | 5-153.0 | --259 |      |       |     |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 322.    | I ≤   | N/S  |       |     |       |        |
|         | 0-328.6 | --258 |      |       |     |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 406.    | I ≤   | N/S  |       |     |       |        |
|         | 1-410.0 | --255 |      |       |     |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 608-614 | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --253 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 14      | I ≤   | N/S  |       |     |       |        |
|         | 00-1427 | --255 |      |       |     |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 1610.6  | I ≤   | N/S  |       |     |       |        |
|         | -1613.8 | --238 |      |       |     |       |        |
|         | MHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 1.      | I ≤   | N/S  |       |     |       |        |
|         | 66-1.67 | --251 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 2       | I ≤   | N/S  |       |     |       |        |
|         | .69-2.7 | --247 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 4       | I ≤   | N/S  |       |     |       |        |
|         | .99-5.0 | --241 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+

+---------+---------+-------+------+-------+-----+-------+--------+
| S       | Fr      | In    |      | Refe  | \%  | S     | Co     |
| ervices | equency | terfe |      | rence |     | ource | mments |
|         |         | rence |      |       | T   |       |        |
| Systems | Bands   | Prote |      | BW    | ime | Doc   |        |
|         |         | ction |      |       |     | ument |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         |         | CW &  | P    |       |     |       |        |
|         |         | Nois  | ulse |       |     |       |        |
|         |         | elike |      |       |     |       |        |
|         |         |       | O    |       |     |       |        |
|         |         |       | ther |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Radio   | 10      | I ≤   | N/S  | 1 Hz  | N/S | Rec.  | None   |
| As      | .6-10.7 | --240 |      |       |     | ITU-R |        |
| tronomy | GHz     | dBW   |      |       |     |       |        |
|         |         |       |      |       |     | R     |        |
| (cont.) |         |       |      |       |     | A.769 |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 15.     | I ≤   | N/S  |       |     |       |        |
|         | 35-15.4 | --233 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 22      | I ≤   | N/S  |       |     |       |        |
|         | .1-22.5 | --233 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 23      | I ≤   | N/S  |       |     |       |        |
|         | .6-24.0 | --233 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 31      | I ≤   | N/S  |       |     |       |        |
|         | .3-31.8 | --228 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 42      | I ≤   | N/S  |       |     |       |        |
|         | .5-43.5 | --227 |      |       |     |       |        |
|         | GHz     | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 86-92   | I ≤   | N/S  |       |     |       |        |
|         | GHz     | --222 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 105-116 | I ≤   | N/S  |       |     |       |        |
|         | GHz     | --222 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 182-185 | I ≤   | N/S  |       |     |       |        |
|         | GHz     | --216 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 217-231 | I ≤   | N/S  |       |     |       |        |
|         | GHz     | --215 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 265-275 | I ≤   | N/S  |       |     |       |        |
|         | GHz     | --213 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+

+---------+---------+-------+------+-------+-----+-------+--------+
| S       | Fr      | In    |      | Refe  | \%  | S     | Co     |
| ervices | equency | terfe |      | rence |     | ource | mments |
|         |         | rence |      |       | T   |       |        |
| Systems | Bands   | Prote |      | BW    | ime | Doc   |        |
|         |         | ction |      |       |     | ument |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         |         | CW &  | P    |       |     |       |        |
|         |         |       | ulse |       |     |       |        |
|         |         | Nois  |      |       |     |       |        |
|         |         | elike | O    |       |     |       |        |
|         |         |       | ther |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
| Very    | 325.3   | I ≤   | N/S  | 1 Hz  | N/S | Rec.  | None   |
| Long    | MHz     | --215 |      |       |     | ITU-R |        |
| B       |         | dBW   |      |       |     |       |        |
| aseline |         |       |      |       |     | R     |        |
|         |         |       |      |       |     | A.769 |        |
| Interfe |         |       |      |       |     |       |        |
| rometry |         |       |      |       |     |       |        |
|         |         |       |      |       |     |       |        |
| (VLBI)  |         |       |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 611 MHz | I ≤   | N/S  |       |     |       |        |
|         |         | --211 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 1413.5  | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --209 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 2695    | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --204 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 4995    | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --198 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 10650   | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --192 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 15375   | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --187 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 23800   | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --192 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 43000   | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --173 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+
|         | 86000   | I ≤   | N/S  |       |     |       |        |
|         | MHz     | --166 |      |       |     |       |        |
|         |         | dBW   |      |       |     |       |        |
+---------+---------+-------+------+-------+-----+-------+--------+

**REFERENCES:**

[^1]: *Spectrum Policy Task Force Seeks Public Comment on Issues Related
    to Commission's Spectrum Policies,* Public Notice*,* ET Docket No.
    02-135, DA-02-1311, 17 F.C.C. Rca. 10560, Federal Communications
    Commission (2002).

[^2]: *Spectrum Policy Task Force, Interference Protection Working Group
    Report* (Working Group Report), ET Docket No. 02-135, at
    [www.fcc.gov/sptf/](http://www.fcc.gov/sptf/), Federal
    Communications Commission ( 2002).

[^3]: *Spectrum Policy Task Force* *Report,* ET Docket No. 02-135,
    DOC-228542, Federal Communications Commission ( 2002).

[^4]: Working Group Report, at 5 (Remarks by Dr. Paul Steffes).

[^5]: *Protection Ratios for Spectrum Sharing Investigations,* Rec.
    ITU-R SM. 669-1, (1994).

[^6]: *Communications Receiver Performance Degradation Handbook*,
    Electromagnetic Compatibility Analysis Center, Annapolis, Maryland
    (1987).

[^7]: *Manual of Regulations & Procedures for Federal Radio Frequency
    Management* (Manual), National Telecommunications and Information
    Administration, at Chapter 6 (September 2003).

[^8]: ITU, Radio Radio Regulations, Geneva, Volume I, Article 1 (2001);
    Manual, at Chapter 6; 47 C.F.R. § 2.1.

[^9]: Radio Regulations, Appendix 7; Rec. ITU-R F.758, *Consideration in
    the development of criteria for sharing between the terrestrial
    fixed services and other services* (2003); Rec ITU-R F.1101,
    *Characteristics of digital fixed wireless systems below about 17
    GHz* (1994); Rec ITU-R F.1102-1, *Characteristics of fixed wireless
    systems operating in frequency bands above about 17 GHz* (2002); TIA
    TSB 10-F, *Interference Criteria for Microwave Systems* (TIA TSB
    10-F), Telecommunications Industry Association*,* Arlington,
    Virginia (1994).

[^10]: Rec. ITU-R F.1189-1, *Error performance objectives for constant
    bit rate digital paths at or above the primary rate carried by
    digital radio-relay systems which may form part or all of the
    national portion of a 27 500 km hypothetical reference path*
    (1997)*.*

[^11]: 47 CFR §101.105.

[^12]: Rec. ITU-R F.1094, *Maximum allowable error performance and
    availability degradations to digital radio-relay systems arising
    from interference from emissions and radiations from other sources*
    (1995)*.*

[^13]: Rec. ITU-R F.1108, *Determination of the criteria to protect
    fixed service receivers from the emissions of space stations
    operating in non-geostationary orbits in shared frequency bands*
    (2000)*.*

[^14]: Rec. ITU-R F.1495, *Interference criteria to protect the fixed
    service from time varying aggregate interference from other services
    sharing the 17.7-19.3 GHz band on a co-primary basis* (2000).

[^15]: Rec. ITU-R F.1190*,* *Protection criteria for digital radio-relay
    systems to ensure compatibility with radar systems in the
    radiodetermination service* (1995).

[^16]: NTIA, Report 02-393, *Measurements of Pulsed Co-Channel
    Interference in a 4-GHz Digital Earth Station Receiver* (2002)*.*

[^17]: TIA TSB 10-F, at Sec. 4.2.3.

[^18]: TIA TSB 10-F, at Sec. 2.5.5 & Appendix B.

[^19]: TIA TSB 10-F, at Annex F-3.5.

[^20]: TIA TSB 10-F, at Sec. 2.5.6.

[^21]: Rec. ITU-R S.1062-2, *Allowable error performance for a
    hypothetical reference digital path operating at or above the
    primary rate* (1999)*.*

[^22]: Rec. ITU-R S.1323-1, *Maximum permissible levels of interference
    in a satellite network (GSO/FSS; non-GSO/FSS; non-GSO/MSS feeder
    links) in the fixed-satellite service caused by other codirectional
    networks below 30 GHz* (2003)*.*

[^23]: Rec. ITU-R S.1429, *Error performance objectives due to
    internetwork interference between GSO and non-GSO FSS systems for
    hypothetical reference digital paths operating at or above the
    primary rate carried by systems using frequencies below 15 GHz*
    (2000)*.*

[^24]: Rec. ITU-R S.614-3, *Allowable error performance for a
    hypothetical reference digital path in the fixed-satellite service
    operating below 15 GHz when forming part of an international
    connection in an integrated services digital network* (1994)*.*

[^25]: Rec. ITU-R S.735-1, *Maximum permissible levels of interference
    in a geostationary-satellite network for an HRDP when forming part
    of the ISDN in the fixed-satellite service caused by other networks
    of this service below 15 GHz* (1995)*.*

[^26]: Rec. ITU-R S.522-5, *Allowable bit error ratios at the output of
    the hypothetical reference digital path for systems in the
    fixed-satellite service using pulse-code modulation for telephony*
    (1994)*.*

[^27]: Rec. ITU-R S.523-4, *Maximum permissible levels of interference
    in a geostationary-satellite network in the fixed-satellite service
    using 8-bit PCM encoded telephony, caused by other networks of this
    service,* (1992)*.*

[^28]: Rec. ITU-R S.671-3, *Necessary protection ratios for narrow-band
    single channel-per-carrier transmissions interfered with by analogue
    television carriers* (1994)*.*

[^29]: Rec. ITU-R S.1420, *Performance for broadband integrated services
    digital network asynchronous transfer mode via satellite* (1999)*.*

[^30]: Rec. ITU-T G.826, (*End-to-end error performance parameters and
    objectives for international, constant bit-rate digital paths and
    connections* (2002).

[^31]: Rec. ITU-T G.821, *Error performance of an international digital
    connection operating at a bit rate below the primary rate and
    forming part of an Integrated Services Digital Network* (2002).

[^32]: Rec. ITU-R S.1432, *Apportionment of the allowable error
    performance degradations to fixed satellite service (FSS)
    hypothetical reference digital paths arising from time invariant
    interference for systems operating below 15 GHz* (2000)*.*

[^33]: Rec. ITU-R S.738, *Procedure for determining if coordination is
    required between geostationary-satellite networks sharing the same
    frequency bands* (1992)*.*

[^34]: Rec. ITU-R SF.739, *Additional methods for determining if
    detailed coordination is necessary between geostationary-satellite
    networks in the fixed-satellite service sharing the same frequency
    bands,* (1992)*.*

    This page intentionally blank.

[^35]: Rec. ITU-R M. 1461, *Procedures for Determining the Potential for
    Interference Between Radars Operating in the Radiodetermination
    Service and Systems in Other Services* (2003)*.*

[^36]: Rec. ITU-R M. 1462, *Characteristics of and Protection Criteria
    for radars operating in the Radiolocation Service in the Frequency
    Range 420-450 MHz* (2000).

[^37]: Rec. ITU-R M. 1463, *Characteristics of and Protection Criteria
    for Radars Operating in the Radiodetermination Service in the
    Frequency Band 1215-1400 MHz* (2000)*.*

[^38]: Rec. ITU-R M. 1464, *Characteristics of and Protection Criteria
    for Radionavigation and Meteorological Radars Operating in the Band
    2700-2900 MHz* (2003).

[^39]: Rec. ITU-R M. 1313, *Technical and Operational Characteristics
    and Protection Criteria of Maritime Radionavigation Radars in the
    Band 2900-3100 MHz* (2000)

[^40]: Rec. ITU-R M. 1460, *Technical and Operational Characteristics
    and Protection Criteria of Radiodetermination and Meteorological
    Radars in the 2900-3100 MHz band* (2000)*.*

[^41]: Rec. ITU-R M. 1465, *Characteristics of, and Protection Criteria
    for Radars Operating in the Radiodetermination Service in the
    Frequency Band 3100-3700 MHz* (2000).

[^42]: Rec. ITU-R M. 1638, *Characteristics of and protection criteria
    for sharing studies for radiolocation, aeronautical radionavigation
    and meteorological radars operating in the frequency bands between
    5250 and 5850 MHz* (2003)*.*

[^43]: Rec. ITU-R M. 1644, *Technical and operational characteristics,
    and criteria for protecting the mission of radars in the
    radiolocation and radionavigation service operating in the frequency
    band 13.75-14 GHz* (2003)*.*

[^44]: Rec. ITU-R M. 1466, *Technical and Operational Characteristics of
    Radars Operating in the Radionavigation Service in the Frequency
    Band 31.8-33.4 GHz* (2003)*.*

[^45]: Rec. ITU-R M. 1640, *Characteristics of, and protection criteria
    for sharing studies for radars operating in the radiodetermination
    service in the frequency band 33.4-36 GHz* (2003)*.*

[^46]: Regulation 12, Chapter V of the *International Convention for the
    Safety of Life at Sea (SOLAS),* as amended (1974).

[^47]: SUR.ET1.ST01.1000-STD-01-01, *Standard Document for Radar
    Surveillance in en-Route Airspace and Major Terminal Areas*,
    Eurocontrol (March 1997).

[^48]: Report ITU-R M.2032, *Tests illustrating the Compatibility
    between Maritime Radionavigation radars and Emissions from
    radiolocation Radars in the Band 2900-3100 MHz* (2002).

[^49]: Rec. ITU-R M. 1372-2, *Efficient Use of the Radio Spectrum by
    Radar Stations in the Radiodetermination Service* (2003)*.*

[^50]: *Revision of Part 15 of Commission's Rules Regarding
    Ultra-Wide-Band Transmissions Systems, First Report and Order,* ET
    Docket No. 98-153, 17 F.C.C. Rcd. 7435 (2002)

[^51]: NTIA Special Publication 01-43, *Assessment of Compatibility
    Between Ultrawideband Devices and Selected Federal Systems,* (2001).

[^52]: FAA 6050.32A, *Spectrum Management Regulations and Procedures
    Manual,* Federal Aviation Administration (May 1998).

[^53]: Rec. ITU-R SM. 1009-1, *Compatibility between the
    Sound-Broadcasting Service in the Band 87-108 MHz and the
    Aeronautical Services in the Band 108-137 MHz* (1995)*.*

[^54]: Rec. ITU-R SM. 1140, *Test Procedures for Measuring Aeronautical
    Receiver Characteristics used for Determining Compatibility Between
    the Sound-Broadcasting Service in the Band of about 87-108 MHz and
    the Aeronautical Services in the Band 108-118 MHz* (1995)*.*

[^55]: RTCA/DO-143, *Minimum Operational Performance Standards Airborne
    Radio Marker Beacon Receiving Equipment Operating on 75 MHz,* RTCA,
    at 5 (1970)*.*

[^56]: RTCA DO-189, *Minimum Operational Performance Standards for
    Airborne Distance Measuring Equipment (DME) Operating within the
    Radio Frequency Range of 960-1215 MHz*, RTCA (1985).

[^57]: *International Standards and Recommended Practices Annex 10 to
    the Convention on International Civil Aviation,* Volume 1 (Radio
    Navigation Aids) Fifth Edition (1996).

[^58]: FAA-E-2716, Specification *for Mode Select Beacon System (Mode S)
    Sensor*, Federal Aviation Administration, Amendment 2 (1983).

[^59]: RTCA/DO-181A, *Minimum Operational Performance Standards for Air
    Traffic Control Radar Beacon System/ Mode Select (ATCRBS/Mode S)
    Airborne Equipment,* RTCA (January 1992).

[^60]: In the United States the SBAS is the Wide Area Augmentation
    System (WAAS) and the GBAS is the Local Area Augmentation System
    (LAAS). These augmentation systems are capable of supporting both
    GPS and GLONASS signal formats.

[^61]: Rec. ITU-R M. 1477, *Technical and Performance Characteristics of
    Current and Planned Radionavigation-Satellite Service
    (Space-to-Earth) and Aeronautical Radionavigation Service Receivers
    to be considered in Interference Studies in the Band 1559-1610 MHz*
    (2000).

[^62]: RTCA/DO-229B, *Minimum Operational Performance Standard for
    GPS/Wide area Augmentation System Airborne Equipment,* RTCA (January
    1996).

[^63]: Category I, II, and III approaches are required for different
    landing visibility conditions in terms of vertical visibility
    ceiling and runway visual ranges; the visibility decreasing with
    increasing category numbers.

[^64]: IEC 61108-1**,** *Global Navigation Satellite System (GNSS), Part
    1: Global Positioning System (GPS) Receiver Equipment Performance
    Standard, Methods of Testing and Required Results,* International
    Electrotechnical Commission (July 2003).

[^65]: Rec. ITU-R M.1479, *Technical Characteristics and Performance
    Requirements of Current and Planned Radionavigation-Satellite
    Service (Space-to-Space) Receivers to be Considered in Interference
    Studies in the Frequency Bands 1215-1260 MHz and 1559-1610 MHz*
    (2000).

[^66]: In addition to broadcasting, other types of transmissions are
    permissible including various data services under FCC regulations.

[^67]: All bands are exclusively for non-federal use.

[^68]: Television channels 60 through 69 are to be reallocated for
    commercial LMR and public safety use after the digital television
    transition date, which is no earlier than December 31, 2006.

[^69]: Rec. ITU-R BT.1368, *Planning criteria for digital terrestrial
    television services in the VHF/UHF bands* (2002).

[^70]: Rec. ITU-R BT.655, *Radio-frequency protection ratios for AM
    vestigial sideband terrestrial television systems interfered with by
    unwanted analog vision signals and their associated sound signals*
    (2000).

[^71]: Vision modulation may be either positive or negative. With
    positive modulation, the sync pulse tips are held at the
    zero-modulation level, whilst peak white is 100% and black level
    around 30%. With negative modulation, the sync tips are at 100%,
    black level around 77% and peak white 20%. This method has the
    advantage that there is a portion of the waveform that is always at
    100% modulation, so that the receiver can measure the carrier
    strength and adjust its automatic gain control accordingly.

[^72]: 47 CFR 73.525, *TV Channel 6 protection,* Federal Communications
    Commission (October 2002).

[^73]: Telecommunications, Part 73, Section 623, *DTV applications and
    changes to DTV allotments,* Federal Communications Commission
    (October 2002).

[^74]: 47 CFR 90.545, *tv/dtv interference protection criteria,* Federal
    Communications Commission (October 2002).

[^75]: Channel 200 (87.9 MHz) is available by certain Class D stations
    only on a non-interference basis to TV Channel 6 and adjacent
    channel non-commercial educational FM stations.

[^76]: Rec. ITU-R BS.412, *Planning standards for terrestrial FM sound
    broadcasting at VHF* (1998)*.*

[^77]: The 75 kHz maximum frequency deviation is specified under
    "Percentage modulation*"* in 47 CFR 73.310.

[^78]:
    > A site that does not meet the minimum separation requirement is
    > "short spaced".

[^79]: 47, CFR 73.213, Federal Communications Commission (2002); 47 CFR
    73.215, *Contour protection for short spaced assignments*, Federal
    Communications (2002).

[^80]: IPC for radio stations not meeting the distance separation
    requirements.

[^81]: All of these bands are allocated to the BSS for non-federal use
    only.

[^82]: According to allocation footnote US327, the band 2310-2360 MHz is
    allocated to the BSS (sound) and complemen­tary terrestrial BS on a
    primary basis. Such use is limited to digital audio broadcast­ing and
    is subject to the provisions of Resolution 528 of the ITU RR*.*

[^83]: According to allocation footnote NG101, the band 2310-2360 MHz is
    allocated to the BSS (sound) and complemen­tary terrestrial BS on a
    primary basis. Such use is limited to digital audio broadcast­ing and
    is subject to the provisions of Resolution 528 of the ITU RR*.*

[^84]: This allocation will come into effect in 2007 (see allocation
    footnote NG163).

[^85]: Rec. ITU-R BO.1293-1, *Protection Masks and Associated
    Calculation Methods for Interference into Broadcast-Satellite
    Systems Involving Digital Emissions* (2000).

[^86]: Rec. ITU-R BO.600-1, *Standardized set of test conditions and
    measurement procedures for the subjective and objective
    determination of protection ratios for television in the terrestrial
    broadcasting and the broadcasting-satellite services* (1986).

[^87]: Weighting refers to the practice of filtering prior to
    measurement to reduce certain noise frequency components in a manner
    corresponding to human audio perception. Without weighting, the true
    S/N would be underestimated, because humans cannot perceive all the
    noise entering the measurement equipment.

[^88]: Reports of the CCIR, Annex to Volumes X and XI -- Part 2, Report
    634-4, *Broadcasting-Satellite Service (Sound and Television)
    Measured interference protection ratios for planning television
    broadcasting systems* (1990).

[^89]: Recommendations and Reports of the CCIR, Volume X, Broadcasting
    Service (Sound), Report 796, *Determination of Radio-Frequency
    Protection Ratio for Frequency-Modulation Broadcasting Receivers*
    (1978).

[^90]: Appendix 30, of the ITU Radio Regulations, *Provisions for all
    services and associated Plans and List for the
    broadcasting-satellite service in the frequency bands 11.7-12.2 GHz
    (n Region 3), 11.7-12.5 GHz (in Region 1) and 12.2-12.7 GHz (in
    Region 2)* (2001)*.*

[^91]: Appendix 30 of the ITU Radio Regulations, Annex 3, *Method for
    determining the limiting interfering power flux-density at the edge
    of a broadcasting-satellite service area in the frequency bands
    11.7-12.2 GHz. (in Region 3), 11.7-12.5 GHz (in Region 1) and
    12.2-12.7 GHz (in Region 2) and for calculating the power
    flux-density produced there by a terrestrial station* (2001).

[^92]: Appendix 30 of the ITU Regulations, Annex 1, Section 3, *Limits
    to the change in power flux-density to protect the
    broadcasting-satellite service in Regions 1 and 2 in the band
    12.2-12.5 GHz and in Region 3 in the band 12.5-12.7 GHz* (2001).

[^93]: Rec. ITU-R BO.1297, *Protection Ratios to be Used for Planning
    Purposes in the Revision of the Appendices 30 (Orb-85) and 30A
    (Orb-88) Plans of the Radio Regulations in Regions 1 and 3* (1997).

[^94]: Rec. ITU-R BO.1444, *Protection of the BSS in the 12 GHz band and
    associated feeder links in the 17 GHz band from interference caused
    by non GSO FSS systems* (2000).

[^95]: *Authorizing Multi Video Distribution and Data Service in the
    Direct Broadcast Satellite Band at 12 Ghz, First Report and Order
    and Further Notice of Proposal Rule Making*, ET Docket No. 98-206,
    RM-9147, RM-9245, FCC 00-418, 16 F.C.C. Rcd 4096 (2000).

[^96]: MVDDS refers to Multi-channel Video Distribution and Data
    Service.

[^97]: *Amendments of parts 2 and 25 of the Commission 's Rules to
    permit operation of NGSO FSS systems co-frequency with GSO and
    terrestrial systems in the Ku-band frequency range*; For the
    Memorandum Opinion and Order, ET Docket No. 98-206. FCC, 03-97, 18
    F.C.C. Rcd.8428, 8435, n. 47 (2003).FCC 03-97 (FCC 03-97), page 7,
    footnote 47 for more information.

[^98]: Mitre Technical Report, *Analysis of Potential MVDDS Interference
    to DBS in the 12.2-12.7 GHz Band,* Mitre Corporation, McLean,
    Virginia (April 2001).

[^99]: FCC 03-97, §7.

[^100]: DBS earth stations were pointed toward the southern hemisphere,
    whereas MVDDS sites were assumed to be to the north, and possibly
    unaffected by the same rain fronts.

[^101]: Rain margin (A~Rm~) simply accounts for the decrease in C due to
    rain. A~eRm~ also accounts for the increase in I due to the presence
    of MVDDS.

[^102]: VSB refers to vestigial side-band.

[^103]: The R designation indicates communications relating to safety
    and regularity of flights primarily along national or international
    civil air routes.

[^104]: The (OR) designation indicates communications primarily outside
    national or international civil air routes.

[^105]: NTIA Manual, Annex I, (September 2003).

[^106]: This noise refers to the RF noise environment.

[^107]: Spectrum XXI is a program intended for use by all government
    agencies to aid in submitting systems for spectrum approval by NTIA.

[^108]: JSC-CR-96-016B, 1998, *JSMSW* *Interference Analysis Algorithms
    Consulting Report*, Department of Defense, Joint Spectrum Center,
    Annapolis, Maryland (April 1998).

[^109]: The FH signal was treated as a pulsed signal.

[^110]: CCIR Study Programme 18B/1, Report 826-1, "*Examples of Band by
    Employing Spread-Spectrum Techniques,"* Reports of the CCIR, 1990
    Annex to Volume 1, Printed in Geneva, Switzerland (1990).

[^111]: NTIA Special Publication 95-32, *Spectrum Reallocation Final
    Report, Response to Title VI - Omnibus Budget Reconciliation Act of
    1993* (February 1995).

[^112]: ITU-R Rec. M.687-2, 02, *International Mobile
    Telecommunications-2000,* Part 2 (1997)

[^113]: NTIA Special Publication 01‑46, *The Potential for Accommodating
    Third Generation Mobile Systems in the 1710-1850 MHz Band: Federal
    Operations, Relocation Costs and Operational Impacts*, Final Report
    (March 2001).

[^114]: NTIA Technical Memorandum 87-122, *Assessment of Digital Radio
    Voice Protection for Government Land-Mobile Use* (July 1987).

[^115]: TSB-88A, *Wireless Communications Systems - Performance in Noise
    and Interference-Limited Situations - Recommended Methods for
    Technology-Independent Modeling, Simulation, and Verification*,
    Telecommunications Industry Association, Arlington, Virginia (1999).

[^116]: CPC is a measure of the BER and vehicular Doppler fading rate
    required to deliver a specific mean opinion score (MOS) for the
    specific modulation.

[^117]: DAQ is a measure similar to Circuit Merit with additional
    definitions for digitized voice and a static SINAD equivalent
    intelligibility when subjected to multipath fading.

[^118]: Rec. ITU-R M.1073-1, *Digital Cellular Land Mobile
    Telecommunication Systems* (1997).

[^119]: Rec. ITU-R M.1388, *Threshold Levels to Determine the Need to
    Coordinate Between Space Stations in the Broadcasting-Satellite
    Service (Sound) and Particular Systems in the Land Mobile Service in
    the Band 1452-1492 MHz* (1999).

[^120]: Rec. ITU-R SM.851-1, *Sharing Between the Broadcasting Service
    and the Fixed and/or Mobile Services in the VHF and UHF Bands*
    (1993).

[^121]: NTIA Report 99-362, *Evaluation of Marine VHF Radios:
    Performance in the Savannah, Ga., and New Orleans, La., Port Areas*
    (April 1999).

[^122]: NTIA Report 00-376, *Electromagnetic Compatibility Between
    Marine Automatic Identification and Public Correspondence Systems in
    the Maritime Mobile VHF Band* (August 2000).

[^123]: NTIA Report 00-343, *Assessment of Compatibility Between 25 and
    12.5 kHz Channelized Marine VHF Radios* (August 1997).

[^124]: NTIA Report 99-363, *Evaluation of Marine VHF Radios: Compliance
    to IEC Receiver Standards* (April 1999); IEC 1097-7, *Global
    Maritime Distress and Safety System (GMDSS): Shipborne VHF
    radiotelephone transmitter and receiver Operational and performance
    requirements Methods of testing and required test results*,
    International Electrotechnical Commission (1996).

[^125]: ICAO Annex 10 Volume V Chapter 4 *Utilization of Frequencies
    Above 30 MHz,* International Civil Aviation Organization (July
    1996).

[^126]: Rec. ITU-R M.547, *Noise objectives in the hypothetical
    reference circuit for systems in the maritime mobile-satellite
    service* (1978).

[^127]: Rec. ITU-R M.552, *Quality objectives for 50-baud start-stop
    telegraph transmission in the maritime mobile-satellite service*
    (1978).

[^128]: Rec. ITU-R M.1229, *Performance objectives for the digital
    aeronautical mobile-satellite service (AMSS) channels operating in
    the bands 1 525 to 1 559 MHz and 1 626.5 to 1 660.5 MHz not forming
    part of the ISDN* (1997)*.*

[^129]: Rec. ITU-R M.1183, *Permissible levels of interference in a
    digital channel of a geostationary network in mobile-satellite
    service in 1-3 GHz caused by other networks of this service and
    fixed-satellite service* (1995).

[^130]: Rec. ITU-R M.1037, *Bit error performance objectives for
    aeronautical mobile-satellite (R) service (AMS(R)S) radio link*
    (1994).

[^131]: Rec. ITU-R M.1234, *Permissible level of interference in a
    digital channel of a geostationary satellite network in the
    aeronautical mobile-satellite (R) service (AMS(R)S) in the bands 1
    545 to 1 555 MHz and 1 646.5 to 1 656.5 MHz and its associated
    feeder links caused by other networks of this service and the
    fixed-satellite service* (1997).

[^132]: Rec. ITU-R M.1476, *Performance objectives for narrow-band
    digital channels using geostationary satellites to serve
    transportable and mobile Earth stations in the 1-3 GHz range forming
    part of the integrated services digital network* (2000).

[^133]: Rec. ITU-R M.1181*, Minimum performance objectives for
    narrow-band digital channels using geostationary satellites to serve
    transportable and vehicular mobile earth stations in the 1-3 GHz
    range, not forming part of the ISDN* (1995).

[^134]: Rec. ITU-R M.1230, *Performance objectives for space-to-Earth
    links operating in the mobile-satellite service with
    non-geostationary satellites in the 137-138 MHz band* (1997).

[^135]: Rec. ITU-R M.1231, *Interference criteria for space-to-Earth
    links operating in the mobile-satellite service with
    non-geostationary satellites in the 137-138 MHz band* (1997).

[^136]: Rec. ITU-R M.1232, *Sharing criteria for space-to-Earth links
    operating in the mobile-satellite service with non-geostationary
    satellites in the 137-138 MHz band* (1997).

[^137]: Rec. ITU-R M.1478, *Protection criteria for Cospas-Sarsat search
    and rescue processors in the band 406-406.1 MHz* (2004)*.*

[^138]: Rec. ITU-R SA.363-5, *Space Operation Systems: Frequencies,
    bandwidths and protection criteria* (1994); Rec. ITU-R SA.609-1,
    *Protection Criteria for Telecommunication Links for Manned and
    Unmanned Near-Earth Research Satellites* (1992); Rec. ITU-R SA.1155,
    *Protection Criteria Related to the Operation of Data Relay
    Satellite Systems* (1995)*;* Rec. ITU-R SA.1157, *Protection
    Criteria for Deep-Space Research* (1995)*,* Rec. ITU-R SA.1396,
    *Protection Criteria for the Space Research Service in the 37-38 GHz
    and 40-40.5 GHz bands* (1999)*.*

[^139]: Rec. ITU-R SA.1263, *Interference Criteria for Meteorological
    Aids Operated in the 400.15-406 MHz and 1668.4-1700 MHz Bands*
    (1997)*.*

[^140]: Rec. ITU-R SA.1022-1, *Methodology for Determining Interference
    Criteria for Systems in the Earth Exploration-Satellite and
    Meteorological-Satellite Services* (1999)*.*

[^141]: Rec. ITU-R SA.1025-3, *Performance Criteria for Space-to-Earth
    Data Transmission Systems Operating in the Earth
    Exploration-Satellite and Meteorological-Satellite Services using
    Satellite in Low-Earth Orbit* (1999)*.*

[^142]: Rec. ITU-R SA.1026-3, *Interference Criteria for Space-to-Earth
    Data Transmission Systems Operating in the Earth
    Exploration-Satellite and Meteorological-Satellite Services using
    Satellite in Low-Earth Orbit* (1999)*.*

[^143]: Rec. ITU-R SA.1159-2, *Performance Criteria for Data
    Transmission and Direct Data Readout Systems Operating in the Earth
    Exploration-Satellite and Meteorological-Satellite Services using
    Satellites in Geostationary Orbit* (1999)*.*

[^144]: Rec. ITU-R SA.1160-2, *Interference Criteria for Data
    Transmission and Direct Data Readout Systems Operating in the Earth
    Exploration-Satellite and Meteorological-Satellite Services using
    Satellites in Geostationary Orbit* (1999).

[^145]: Rec. ITU-R SA.1162-1, *Telecommunication Requirements and
    Performance Criteria for Service Links in Data Collection and
    Platform Location Systems in the Earth Exploration-Satellite and
    Meteorological-Satellite Services* (2003)*.*

[^146]: Rec. ITU-R SA.1163-2, *Interference Criteria for Service Links
    in Data Collection Systems in the Earth Exploration-Satellite and
    Meteorological-Satellite Services* (1999)*.*

[^147]: Rec. ITU-R SA.514-3, *Interference Criteria for Command and Data
    Transmission Systems Operating in the Earth Exploration-Satellite
    and Meteorological-Satellite Services* (1997)*.*

[^148]: Rec. ITU-R SA.1028-1, *Performance Criteria for Satellite
    Passive Remote Sensing* (2003)*.*

[^149]: Rec. ITU-R SA.1029-1, *Interference Criteria for Satellite
    Passive Remote Sensing* (2003)*.*

[^150]: Rec. ITU-R SA.1166-2, *Performance and Interference Criteria for
    Active Spaceborne Sensors* (1999)*.*

[^151]: Rec. ITU-R RA.769-1, *Protection Criteria Used for
    Radioastronomical Measurements* (2003)*.*