The Second Wireless
Revolution
March 10th, 2005
Koichiro Hayashi, Ph.D., LL.D
Vice President and Professor, Institute ofInformation Security
Visiting Professor, Institute for Media andCommunications Research, Keio University
e-mail hayashi@iisec.ac.jp
URL http://lab.iisec.ac.jp

Tragedy of the Titanic in 1912
 Physical defects in the structure of theship Communication failure to understandignition signals
 Communication failure to understand SOS
signals About ５０％ capacity of lifeboats to thecapable passengers

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The Titanic Syndrome
Domestic U.S. spectrum policy and regulation began
90 years ago. Largely as a consequence of thecommunications failures associated with the sinkingof the Titanic, the Federal government establishedcontrol of the electromagnetic spectrum.
The first international radio conference took place in
1903, followed by another in 1906. The second
conference adopted a convention requiring receipt ofpriority distress calls from ships and created the firsttwo radio frequency service categories: general public
service in the 187-500 kHz band and long-range orother services for assignment in other frequencies.
Source: FCC-SPTF [2002]

3Three Different Histories?
Yochai Benkler refers to this history of radio
regulation, which justifies governmental control ofspectrum as the necessary response to conflicting uses,
as the "official history." He contrasts this with therevisionist history told by the private property rights
theorists. This revision attributes government control
not to necessity, but to the coinciding interests ofgovernment, which wanted control, and incumbent
broadcasters, who wanted protection from competition.
A third history, which Benkler himself tells, is a story
not of technical or political necessity, but of networkarchitecture. According to Benkler, it was theparticular and historically contingent businessarrangements of broadcasters and equipment
manufacturers that necessitated the regulatory
structure Congress adopted in 1927 and 1934.
4Source: Goodman[2004]

Four Parameters
The Commission must clearly define the following
basic spectrum rights parameters for all licensed
and unlicensed spectrum uses:

Designated frequency range and bandwidth;
Geographic scope of right to operate;
Maximum RF output, both in-band and out-of-band;
andInterference protection, i.e. the maximum level ofnoise/interference that the spectrum user must
accept from other RF sources.
Source: FCC-SPTF [2002]

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Three Spectrum Usage Models
“Command-and-control” model. The traditional process of spectrum managementin the United States, currently used for most spectrum within the Commission’s
jurisdiction, allocates and assigns frequencies to limited categories of spectrum
users for specific government-defined uses. Service rules for the band specify
eligibility and service restrictions, power limits, build-out requirements, andother rules.

“Exclusive use” model. A licensing model in which a licensee has exclusive andtransferable rights to the use of specified spectrum within a defined geographic
area, with flexible use rights that are governed primarily by technical rules toprotect spectrum users against interference. Under this model, exclusive rights
resemble property rights in spectrum, but this model does not imply or require
creation of “full” private property rights in spectrum.

“Commons” or “open access” model. Allows unlimited numbers of unlicensed
users to share frequencies, with usage rights that are governed by technicalstandards or etiquettes but with no right to protection from interference.
Spectrum is available to all users that comply with established technical“etiquettes” or standards that set power limits and other criteria for operation ofunlicensed devices to mitigate potential interference.

6Source: FCC-SPTF [2002]

The 3rd or 4th Way?
1.

The holders of frequency licences can use their spectrum forall purposes, and lease it to others. In some cases, apayment or auction might be required first. This should
satisfy the property rights proponents. （Property Right)

2.

Unused spectrum can be utilised without a licence, subject tolimitations of transmission power and time. (Commons)3.

Unlicensed users must pay a usage fee.
Low-power devices would not be included. But for thoseradiating a stronger signal, usage could be metered by a chipin the transmission equipment, and monthly totals
transmitted to sites run by credit card companies, which
would take care of the payment. The allocation of thecollected revenues would be set according to the sampledusage of different frequency bands and distributed to thelicence holders. (Right of Way)

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* “Command and Control” is out of question.
Source: Noam [2003]7

Broadcasting v. Interactive Comm.

High Power

Receive only

High PowerHigh Power

Trunk Line only
＜Broadcasting ＞＜Interactive Comm.＞

Wireless Dominant

Wireline Dominant8Negroponte Switch＜Past＞＜Future>Broadcasting＝WirelessBroadcasting＝Wireline

Telecommunications＝Wireline

Telecommunications＝Wireless9

Source: Negroponte[1995]

Cell Phones: The First Revolution<Big Zone><Cell>All available spectrum
used within a big zone

All available spectrum repeatedlyused among many cells
10Enabler of Negroponte Switch
 Space Segmentation : cell, etc.
 Time Division : TDMA, packet, etc.

And more to come!!

11More to comeSmart Terminal: Carrier Sense(1) SDR (Software Defined Radio): Smart
radio, agile radio, cognitive radio(2) Mesh Network
Spread Spectrum(1) Direct sequence: IEEE 802.11 series(2) Frequency hopping : Bluetooth(3) CDMA(4) UWB (Ultra Wide Band)
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Smart Terminal
Smart Sender

Dumb Sender

DumbTerminal
SmartTerminal＜Tradition＞＜Revolution>13

Spread Spectrum (1)14

Source:Werbach[2002]

Spread Spectrum (2)Traditional
Transmission
Spread Spectrum
such as Wireless LANPowerUWB（Ultra Wide Band)
Noise Ceiling

Spectrum15Source: Yamada & Fujii[2004]

Interference still matters:“Interference” is defined as follows, according to theCommission’s rules: “The effect of unwanted energy due toone or a combination of emissions, radiations, or inductions
upon reception in a radio-communication system,
manifested by any performance degradation,
misinterpretation, or loss of information which could beextracted in the absence of such unwanted energy.” 47
C.F.R. § 2.1.
 “Harmful interference” is defined as follows: “Interferencewhich endangers the functioning of a radionavigation
service or other safety services or seriously degrades,
obstructs, or repeatedly interrupts a radiocommunication
service operating in accordance with these [international]
Radio Regulations.” 47 C.F.R. § 2.1.
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New Methodology
Interference temperature, expressed in units of degrees Kelvin,can be calculated as the power received by an antenna in watts
divided by the associated RF bandwidth in Hertz and a term
known as Boltzman’s Constant (equal to 1.3807 watt-sec/ºKelvin).
Alternatively, interference temperature can be calculated as thepower flux density available at an antenna in watts per metersquared multiplied by the effective capture area of the receiving
antenna in meters squared divided by both the associated RF
bandwidth in Hertz and Boltzman’s constant. An “interferencetemperature density” can also be defined as the interference
temperature per unit area, expressed in units of ºKelvin permeter squared, and calculated as the interference temperature
divided by the effective capture area of the receiving antenna.
This quantity could be measured for particular frequencies usinga reference antenna and, thereafter, would be independent ofreceiving antenna characteristics.
Source : FCC-SPTF[2002]17

Too PoliticalGiven the substantial agreement on policy direction,
the greatest obstacles to reform are likely to arise
from incumbents deploying political pressure toresist change in the status quo. In recognition of thisreality, many of the policy ideas floated at theconference creatively combine mechanisms thatshould enhance effectiveness in spectrum
management and ease the political pathway towardreform. Participants hoped that political leaders willfind the will to seize on the considerable agreementthat exists among policy specialists across thepolitical spectrum to bring about reform inmanaging across the electromagnetic spectrum.
Source: Aspen Institute[2004]

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How to measure Efficiency (1)The Task Force identified three variations on anddefinitions for the term “efficiency,” as applicable tospectrum management: spectrum efficiency, technicalefficiency, and economic efficiency. Spectrum efficiency
occurs when the maximum amount of information istransmitted within the least amount of spectrum.
Technical efficiency occurs when inputs, such as spectrum,equipment, capital, and labor, are deployed in a mannerthat generates the most output for the least cost. Economicefficiency occurs when all inputs are deployed in a mannerthat generates the most value for consumers. The Task
Force found that spectrum and technical efficiency arecomponents of economic efficiency, but that measuring
spectrum and technical efficiency does not necessarily
provide any meaningful information with respect toeconomic efficiency.
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Source:FCC-SPTF [2002]

How to measure Efficiency (2)The Task Force concluded that the Commission canbest promote economic efficiency by providing
spectrum users with flexibility of spectrum use andease of transferability in order to allow maximizationof the value of the services provided. Flexibility
provides incentives for economically efficient use anddiscourages economically inefficient use by ensuringthat spectrum users will face the opportunity cost of
their spectrum use. In most instances, the applicationof flexible service rules and efficient secondary market
mechanisms are the best means of achieving this goal.
20Source:FCC-SPTF [2002]

Immediately applicable・・・ Mandatory for (at will of or unconscious of) theIncumbent（1）Secondary Market（2）Easement（3）Underlay/Overlay
 Narrowing the Guardband
 Digitization with less Bandwidth Expansion of unlicensed Spectrum
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Underlay Sharing

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Source:Werbach[2002]

Gimme some spectrum says Son
Softbank in Japanese mobile row
By Tony Dennis


AN UNCHARACTERISTIC PUBLIC row has broken out in Japan overspectrum allocated for mobile phone networks. Masayoshi Son, Softbank's
president, has effectively accused the Japanese telecoms regulator of bias.
The Japanese telecoms ministry has just allocated more bandwidth at 800
MHz to two existing operators - NTT DoCoMo and KDDI. But Softbank was
hoping that new entrants would get the allocation when bandwidth became
available.
Softbank has already shaken up the Japanese broadband market and ishoping to do the same thing with wireless. Significantly Softbank wasinterested in using TD-CDMA (sometimes known as Wideband TDD) for
deploying a wireless IP network. While TD-CDMA fits nicely alongside other3G technologies – such as W-CDMA and CDMA2000 – it doesn't easily lend
itself to voice. Hence Softbank's interest in 800 MHz which is ideal for voice.
The Japanese ministry's attitude seems to be that DoCoMo and KDDIalready had 800 MHz base stations so they might as well have the newbandwidth.
Although there are already four Japanese mobile operators – DoCoMo,KDDI, Tu-Ka and Vodafone – Japanese mobile calls are still relatively
expensive. NTT in particular would be loathe to see a low cost mobile phone
operator since around 70 per cent of its profits come from DoCoMo – its
mobile arm.

Source: “the Inquirer” September 7, 2004
http://www.theinquirer.net/?article=1829423References
Aspen Institute[2004] “Spectrum and Network Policy for Next
Generation Telecommunications” Aspen Institute Benkler, Yochai ‘Overcoming Agoraphobia: Building theCommons of the Digitally Networked Environment,’ 11 Harv.
J.L. & Tech. 287, 298 (1998)
 FCC（Federal Communications Commission） Spectrum Policy
Task Force [2002] “Report” ET Docket No. 02-135, FCC
 Goodman, Ellen P.[2004] ‘Spectrum Rights in the Telecosm tocome’ “ San Diego Law Review” Winter 2004
 Negroponte, Nicholas[1995] “Being Digital” Alfred A. Knopf. Inc.
 Noam, Eli[2003] ‘The Third Way for Spectrum’ ‘The Fourth Wayfor Spectrum’ “FT.com” March 13, 2003 and May 29, 2003
 Werback, Kevin[2002] ‘Radio Revolution’ New AmericaFoundation

http://werbach.com/docs/RadioRevolution.pdf
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