F EATURES
http://www.vtsociety.org
Vehicular Technology Society News
Vol. 51, No. 4, issn 1068 5731
November 2004

4
10
20

Multi-carrier techniques for future mobile radio(I) - Background and history
Multi-carrier techniques for future mobile radio(II) - Performance and comparison
42 Volts—The View from Today

Contents
2 VTS Directory
3 Foreword
19 VTS Board of Governors Meeting
25 Land Transportation
28 Automotive Electronics
30 Mobile Radio
39 Standards
42 News
44 Calls for Papers: VPP Conference
44 Calendar of Events

Vehicular Technology Society Directory
Executive Committee

President, Charles Backof
Executive Vice President,
Dennis Bodson
Vice President Mobile Radio,
Eric J. Schimmel
Vice President Motor Vehicles,
Robert A. Mazzola
Vice President Land
Transportation,
Harvey M. Glickenstein
Treasurer, George F. McClure

Board of Governors

Charles Backof (’04)
President
Motorola
8000 W. Sunrise Blvd.
Fort Lauderdale, FL 33322
Tel: 1 954 723 6152
Fax: 1 954 723 6957
EPOR16@email.mot.com
Dennis Bodson (’04)
Executive VP, Standards
Committee
233 N. Columbus St.
Arlington, VA 22203
Tel: 1 703 243 3743
Fax: 1 703 522 4342
bodsond@worldnet.att.com

Secretary, Tracy Fulghum
Ericsson, Inc.
7001 Development Drive
Post Office Box 13969
Research Triangle ParkNC 27709
Tel: 1 919 472 6747
Fax: 1 919 472 6988
tracy.fulghum@ericsson.com

J. R. Cruz (A), Past President
The University of Oklahoma
School of Elec & Comp Eng
202 West Boyd, Room 219
Norman, OK 73019-0631
Tel: 1 405 325 4280
Fax: 1 405 325 3836
jcruz@ou.edu

Transactions
Tan F. Wang
Dept. of Electrical &Computer Engineering
P.O. Box 116130
Gainesville, FL 32611-6130
transactions@vtsociety.org

Mark Ehsani (’05)
Electric Vehicles, Convergence
Fellowship
Texas A&M University
College Station, TX 77843
Tel: 1 979 845 7582
Fax: 1 979 862 1976
ehsani@ee.tamu.edu

Propagation Committee
David Michelson
University of British
Columbia
EL Department
30500 Mound Rd
Warren, MI 48090-9055
Tel: 1 604 985 0214
Fax: 1 604 985 0268
dmichelson@ieee.org
Conference Coordinator
Glenda McClure
1730 Shiloh Lane
Winter Park, FL 32789
Tel: 1 407 657 6419
gmcclure@cfl.rr.com

VTS News Staff
Editor-in-Chief
James M. Irvine
Mobile Comms Group, EEEStrathclyde University
George Street
Glasgow G1 1XW SCOTLAND
Tel: +44 141 548 4072
Fax: +44 141 552 4968
j.m.irvine@ieee.org
Senior Editors
Standards
Dennis Bodson
Executive Vice President

2Tracy Fulghum (’06)
Secretary
Contact details at left
Harvey M. Glickenstein (A)VP Land Transportation
PB Transit & Rail Sys., Inc.
3334 Adams Court
Bensalem, PA 19020
Tel: 1 973 565 4820
Fax: 1 973 824 3140
h.glickenstein@ieee.org
James M. Irvine (’05)
VTS News Editor
Contact details below

Automotive Electronics
William J. Fleming
TRW Vehicle Safety Sys., Inc.
4505 West 26 Mile Road
Washington, MI 48094
Tel: 1 586 781 7394
Fax: 1 586 781 7274
william.fleming@trw.com
Mobile Radio
Javier Gozalvez
C/ San Juan Bosco, nº 14-B 3F
03005 Alicante
SPAIN
j.gozalvez@ieee.org

A. Kent Johnson (A)Past President
Brigham Young University
1225 East Cambridge Court
Provo, UT 84602
Tel: 1 801 378 3726
Fax: 1 801 378 7575
a.k.johnson@ieee.org
Mel Lewis (A)Fairleigh Dickinson
University
1000 River Rd
Teaneck NJ 07666
Tel: 1 201 692 2348
m.lewis@ieee.org
Roger Madden (’05)
PB Farradyne
605 Suwannee Street MS 90
Tallahassee, FL 32399-0450
Tel: 1 850 410 5610
Fax: 1 850 410 5501
r.madden@ieee.org
Tadashi Matsumoto (’04)
Center for WirelessCommunications
University of Oulu
Tutkijantie 2E, FIN-90014,
FinlandTel: 358 400 697 1682
Fax: 358 8 553 2845
tadashi.matsumoto@ee.oulu.fi
Robert A. Mazzola (’06) VP
Motor Vehicles, Convergence
Conference, SAE Liaison,Long Range Planning
6101 Pelican Bay Blvd.
#1602
Naples,Florida 34108.
Tel: 1 231 378 4722
robertmazzola@comcast.net
George F. McClure (’06)
Treasurer, Public Relations/Publicity Committee Chair
1730 Shiloh Lane
Winter Park, FL 32789
Tel: 1 407 647 5092
Fax: 1 407 644 4076
g.mcclure@ieee.org

Transportation Systems
Harvey M. Glickenstein
VP Land Transportation
Tel: 1 973 565 4820
Fax: 1 973 824 3140
h.glickenstein@ieee.org
Professional Activities
Frank E. Lord
35 Hartford Ave.
San Carlos, CA 94070
Tel: 1 650 594 0512
Fax: 1 650 594 0512

Samuel R. McConoughey (’04)
Past President
Mobile Communications
Consulting
13017 Chestnut Oak Drive
Gaithersburg
MD 20878-3556
Tel: 1 301 926 2837
Fax: 1 301 926 2506
mccon@compuserve.com
Tom Rubinstein (’05)
Webmaster,
New member liaison
Motorola
9980 Carroll Canyon Road
P. O. Box 85036
San Diego, CA 92186-9130
Tel: 1 858 530 8432
Fax: 1 858 530 8313
cegr01@email.mot.com
Eric J. Schimmel (’04)
Vice President Mobile Radio
6216 Hollins Drive
Bethesda, MD 20817
Tel: 1 301 530 7987
e.schimmel@ieee.org
Gordon L. Stüber (’06)
Fellows Committee
Georgia Institute of Technology
School of Electrical andComputer Engineering
Atlanta, GA 30332
Tel: 1 404 894 2923
Fax: 1 404 894 7883
stuber@ece.gatech.edu
Raymond C. Trott (’06)
Awards Committees
Trott Communications Group,Inc.
1425 Greenway Drive, # 350
Irving, TX 75038
Tel: 1 972 580 1911
Fax: 1 972 580 0641
ray.trott@trottgroup.com
James A.Worsham, Jr. (’05)
Past Conferences
BellSouth, Room 42U85,
675 W Peachtree Street NE,
Atlanta, GA, 30375
Tel: 1 404 330 0381
Fax: 1 404 330 038

Chapter News & Meetings
Gaspar Messina
9800 Marquetta Drive
Bethesda, MD 20817
Tel: 1 202 418 1348
Fax: 1 202 418 1412
GMESSINA@fcc.gov
Book Reviews
Dirk Pesch
Cork Institute of Technology
Cork
IRELAND
dpesch@cit.ie

November 2004 ❖ IEEE Vehicular Technology Society News

Foreword
James Irvine, Editor

This issue of the VTS News is a little
unusual in that the mobile radio feature articles are two complementary
articles giving more comprehensive
coverage of a significant topic, in thiscase OFDM. The first part offers an
introduction to OFDM and its history,
and is of the normal tutorial nature
the VTS News currently publishes.
The second takes a more detailed lookat the performance of OFDM in comparison to other systems, and is morein-depth than our usual articles. The
articles also feature a very comprehensive list of references covering
OFDM, its development and history.
Tutorial articles are popular, butthere is currently a gap between theoverview articles we publish and thehighly academic papers published in
the Transactions on VehicularTechnology. Feedback from members
is that the Society should be doing

more in the area of relevant information for practising engineers. The
Board has committed more resources
to the VTS News in 2005 to allow forenhanced content, particularly forgraphical work, which allows us totackle more complex articles than
before. I would welcome your feedbackon the types of article we should besoliciting.
The most significant change which
will affect this publication is theplanned transition to a magazine,
which will hopefully take place from2006. A magazine format will allow us
to publish more articles, with some
30% more pages, as well as making ourcontent more accessible through media
such as IEEE XploreTM. While it will
be significant cost to the Society, it is
one that it can afford, and one that will
improve the value of membership in
the Society. In an increasingly elec-

tronic age, there is still a need for quality publications to distil the vast quantities of information our technical area
develops, as well as to report andexplain developments in the field.
The overall aim is to build on thestrengths of the VTS News, retaining
its columns on industry developments
and overview articles accessible tomembers of all technical areas, and toenhance this with more specialist articles of a practical nature. 2005 will seechanges to the administrative structure of the newsletter to match the
new content. We would like to see
more membership involvement in theprocess, so if you have ideas on what
you would like to see in the expanded
content, or would like to get involved
in helping run the VTS News, or simply want to know more about what isplanned, please get in touch with meat the address overleaf.

Copy for upcoming issues of VTS Newsshould reach Dr. James Irvine by:Issue
Due Date
February 2005 December 4, 2004
May 2005
March 5, 2005
August 2005
June 5, 2005
November 2005 September 4, 2005

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at Mobile Communications Group,
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3

A Stroll along Multi-carrier Boulevard to
Next-Generation Plaza (I)—OFDM Background and History
Lajos Hanzo, Byoung-Jo Choi, and Matthias Münster, School of ECS, University of Southampton
In this introductory part of a two part series of articles on
multi-carrier techniques, a background to Orthogonal
Frequency Division Multiplex (OFDM) is provided, complemented by a detailed historical perspective of multicarrier systems, identifying their most critical design
aspects. These systems exhibit numerous attractive features, rendering them eminently eligible for employment
in next-generation wireless systems. It is argued thatsymbol-by-symbol adaptive Orthogonal Frequency
Division Multiplex (OFDM) modems counteract the near
instantaneous channel quality variations and hence
attain an increased throughput in comparison to their
fixed-mode counterparts. By contrast, various diversity
techniques, such as Rake receivers and space-time coding, mitigate the channel quality variations in their effort
to obtain a reduced BER.

Motivation

Although the roll-out of the third-generation (3G) systems [1] has been somewhat delayed, the research community turned its attention to the investigation of nextgeneration multi-carrier transceiver techniques [2, 3, 4].
The next-generation wireless systems are expected tosupport both variable-rate as well as extremely highbitrate services in a wide range of different propagation
environments. Under these propagation conditions it isunrealistic to expect that conventional fixed-mode transceivers might be capable of supporting a time-invariant
wireline-like quality of service and hence near-instantaneously adaptive transceiver techniques [5, 6] havefound their way into the High-Speed Downlink Packet
Access (HSDPA) mode of the 3G systems. Multi-standard
operation is also a salient requirement. As it was argued
in the context of the generic futureproof system design
framework outlined in Chapter 1 of [2], Multi-Carrier(MC) transmission techniques [2, 3, 7], such as
Orthogonal Frequency Division Multiplexing (OFDM)[3] and its frequency domain spreading aided version,
namely MC Code Division Multiple Access (MC-CDMA)
exhibit the highest number of reconfigurable parameters
amongst all potential transceivers schemes that may bereconfigured in an effort to satisfy the aforementioned
challenging system requirements. Another attractive
relative of this MC transceiver family is constituted by
Direct Sequence (DS) MC-CDMA as well as its time-, frequency- and space-time-spreading assisted relatives [2,8, 9]. Since DS MC-CDMA was documented in [2, 8, 9],4following a rudimentary introduction to the subject anda brief tour of the MC transceiver history, this overview
article will consider a number of design aspects pertaining to OFDM and frequency-domain spreading aided MC
communications.

OFDM Basics

In this introductory section we examine OFDM as a meansof counteracting the channel-induced linear distortions
encountered, when transmitting over a dispersive radio
channel. The fundamental principle of orthogonal multiplexing originates from Chang [10], and over the years a
number of researchers have investigated this technique[11–22]. Despite its conceptual elegance, until recently its
employment has been mostly limited to military applications due to implementational difficulties. However, it has
recently been adopted as the new European Digital Audio
Broadcasting (DAB) standard, and this consumer electronics application underlines its significance as a broadcasting
technique [23–27].
In the OFDM scheme of Figure 1, the serial data
stream of a channel is passed through a serial-to-parallel converter, which splits the data into a number of parallel channels. The data in each channel is applied to amodulator, such that for n channels there are n modulators whose carrier frequencies are f0, f1, ..., fn – 1. The frequency difference between adjacent channels is ∆f andthe overall bandwidth w of the N modulated subcarriers
is n∆f.

Figure 1 Simplified block diagram of the orthogonal
parallel modem
November 2004 ❖ IEEE Vehicular Technology Society News

November 2004 ❖ IEEE Vehicular Technology Society News

Adaptive OFDM Basics©Wiley-IEEE Press, Hanzo, Ng, Keller, Webb [4].

As mentioned above, a particularly attractive feature of
OFDM systems is that they are capable of operating without a classic channel equaliser, when communicating overdispersive transmission media, such as wireless channels,
while conveniently accommodating the time- and frequencydomain channel quality fluctuations of the wireless channel.

Figure 2 Instantaneous channel SNR for the 512 OFDM
subcarriers versus time, for an average channel SNR of
16 dB over the channel characterised by the Channel
Impulse Response (CIR) of Figure 3
Time Delay [ns]
0

25

50

75

100 125 150 175 200 225 250 275 300

1.0
0.9
0.8
0.7

Amplitude

These n modulated carriers are then combined togive an OFDM signal. We may view the serial-to-parallel converter as applying every nth symbol to a modulator. This has the effect of interleaving the symbols
entered into each modulator, e.g. symbols S0, Sn, S2n, ...
are applied to the modulator whose carrier frequency is
f1. At the receiver the received OFDM signal is demultiplexed into n frequency bands, and the n modulated signals are demodulated. The baseband signals are thenrecombined using a parallel-to-serial converter. The
plausible benefit of expanding the duration of each subcarrier symbol is that at a given maximum channelinduced dispersion the relative fraction of a subcarrier
symbol that is contaminated by dispersion is reduced bya factor of n.
In the more conventional serial transmission
approach [4], the data is applied directly to the modulator transmitting at a carrier frequency positioned at thecentre of the transmission band. The modulated signal
occupies the entire bandwidth w. When the data istransmitted serially, a deep fade imposed by a mobile
channel inflicts a burst of transmission errors, when thefade extends over the duration of several bits. By contrast, during an n-symbol transmission burst of the conventional serial system, each of the n number of OFDM
subchannel modulators carries only one symbol, each ofwhich has an n times longer duration. Hence, again, afixed duration channel fade would only affect a fractionof the duration of each of the extended-length subcarrier
symbols transmitted in parallel. Therefore the OFDM
system may be able to recover all of the partially fadingcontaminated n subcarrier symbols without transmission errors. Thus, while the serial system exhibits anerror burst, no errors or only few errors may occur using
the OFDM approach.
A further advantage of OFDM is that because the symbol
period has been increased, the channel’s delay spread
becomes a significantly shorter fraction of an OFDM symbol
period than in the serial system, potentially rendering thesystem less sensitive to channel-induced dispersion, thanthe conventional serial system.
A disadvantage of the OFDM approach portrayed in
Figure 1 is its increased complexity in comparison to a conventional serial modem, which is a consequence of employing n subcarrier modulators and transmit filters at thetransmitter as well as n demodulators and receive filters at
the receiver.
However, as it was shown in Chapter 2 of [3], the associated complexity can be substantially reduced by employing
the Discrete Fourier Transform (DFT) for modulating all
subcarriers in a single step. From a tangible physical perspective this may be explained by arguing that all the
OFDM subcarriers are orthogonal complex-valued exponential functions, which have a frequency that is an integer
multiple of the basis frequency f0, exactly as in case of thecomplex-valued exponential basis functions of the
DFT/IDFT. Hence instead of multiplying each subcarrier
individually for example by ±1 as in BPSK modulation, themodulation process implies ‘transforming’ a block of n BPSK
modulated subcarrier symbols in a single step using the
IDFT/DFT, yielding a block of n modulated samples, as illustrated mathematically in [3].
When the number of subcarriers is high, the system’s
complexity may be further reduced by implementing the
DFT with the aid of the Fast Fourier transform (FFT),
again, as it was shown mathematically in [3].

0.6
0.5
0.4
0.3
0.2
0.1
0.0
0

10

20

30

40

50

60

70

80

90

Path-Length Difference [m]Figure 3 Indoor three-path Wireless AsynchronousTransfer Mode (WATM) CIR.
Explicitly, the channel SNR variation versus both time andfrequency of an indoor wireless channel is shown in a threedimensional form in Figure 2 versus both time and frequency, which suggests that OFDM constitutes a convenient
framework for accommodating the channel quality fluctuations of the wireless channel, as will be briefly augmented
below. This channel transfer function was recorded for the5©John Wiley and IEEE Press 2003, Hanzo, Münster, Choi and Keller [3, 28].

ity. The average throughput of each OFDM symbol
constituted by a column of 16 stacked 32-subcarrier subbands was 1 bit per symbol (BPS) in thisexample, as in conventional Binary Phase Shift
Keying (BPSK).
More explicitly, in the centre and bottom subfigures of Figure 4 the modulation mode chosen foreach 32-subcarrier sub-band is shown versus time
for two different high-speed wireless modems communicating at either 3.4 or 7.0 Mbps, respectively,
again, corresponding to an average throughput ofeither 1 or 2 BPS.
However, these adaptive transceiver principles
are not limited to employment in OFDM transmissions. In recent years the concept of intelligent
multi-mode, multimedia transceivers (IMMT) has
emerged in the context of a variety of wireless systems [2, 4, 5, 28–32]. The range of various existing
solutions that have found favour in already operational standard systems has been summarised in
the excellent overview by Nanda et al [31].
The aim of these adaptive transceivers is to provide mobile users with the best possible compromise amongst a number of contradicting design factors, such as the power consumption of the handheld portable station (PS), robustness against
transmission errors, spectral efficiency, teletraffic
capacity, audio/video quality, and so forth [30].
Another design alternative applicable in thecontext of OFDM systems is that the channel quality fluctuations observed, for example, in Figure 2
are averaged out with the aid of frequency-domain
spreading codes, which leads to the concept of freFigure 4 The micro-adaptive nature of the sub-band-adaptive quency-domain spreading aided MC-CDMA [3]. In
OFDM modem. The top graph is a contour plot of the channel SNR this scenario typically only a few chips of thefor all 512 subcarriers versus time. The bottom two graphs show spreading code are obliterated by the frequencythe modulation modes chosen for all 16 32-subcarrier subbands for selective fading, hence the chances are that thethe same period of time. The middle graph shows the performance spreading code and its conveyed subcarrier dataof the 3.4 Mbps sub-band-adaptive modem, which operates at the symbol may still be recoverable. The advantage ofsame bit rate as a fixed BPSK modem. The bottom graph repre- this approach is that in contrast to AOFDM-based
sents the 7.0 Mbps sub-band-adaptive modem, which operated at communications, in MC-CDMA no channel quality
the same bit rate as a fixed QPSK modem. The average channel estimation and signalling are required. Therefore,
SNR was 16 dB
based on the more detailed exposures in [3], OFDM©John Wiley and IEEE Press 2003, Hanzo, Münster, Choi and and MC-CDMA will be comparatively studied in
Keller [3, 28].
the Uncoded Adaptive System, Turbo-Coded Fixed
Modem, and Turbo Coded Adaptive System secchannel impulse response of Figure 3, by simply transformtions of this contribution. We will also consider the employing the impulse response to the frequency domain at regument of Walsh-Hadamard code-based spreading of each sublar time intervals, while its taps fluctuated according to thecarrier’s signal across the entire OFDM bandwidth, which
Rayleigh distribution.
was found to be an efficient frequency-domain fading countThese channel quality fluctuations may be readily
er-measure capable of operating without the employment ofaccommodated with the aid of sub-band-adaptive modulaadaptive modulation [5].
tion as follows. Such an adaptive OFDM (AOFDM) modem
A further technique capable of mitigating the channel qualis characterised by Figure 4, portraying at the top a contour
ity fluctuations of wireless channels is constituted by spaceplot of the aforementioned wireless channel’s signal-to-noisetime coding [6], which will also be considered as an attracratio (SNR) fluctuation versus both time and frequency fortive anti-fading design option capable of attaining a higheach OFDM subcarrier. We note at this early stage thatdiversity gain. Space-time coding employs several transmit
these channel quality fluctuations may be mitigated withand receive antennas for the sake of achieving diversity gain
the aid of frequency-domain channel equalisation, as it wasand hence results in an improved performance.
illustrated both graphically as well as mathematically in [3].
By contrast, in Part 2 of [3] multiple antennas wereWe will briefly revisit this topic also in this contribution at
employed at the base-station for a different reason, namely
a later stage.
for the sake of supporting multiple users, rather than forMore specifically, as seen in Figures 2 and 4, when theachieving transmit diversity gain. This is possible, since thechannel is of high quality—as for example in the vicinity ofusers’ channel impulse responses (CIR) or channel transfer
the OFDM symbol index of 1080—a higher throughout may
functions are accurately estimated and hence these channelbe achieved, than during the periods of lower channel qualtransfer functions may be viewed as unique user-specific6

November 2004 ❖ IEEE Vehicular Technology Society Newssignature sequences, which allow us to both recognise andto demultiplex the simultaneous transmissions of the individual users, in a similar fashion to the unique user-specific spreading codes employed in CDMA systems. We note,however, that this technique is only capable of reliably separating the users communicating within the same bandwidth, if their CIRs are sufficiently different. This assumption is typically valid for the uplink, although it may have alimited validity, when the base station receives from mobile
stations having a similar CIR in its immediate vicinity. By
contrast, different techniques have to be invoked for downlink multi-user transmissions. For reasons of space economy, here we restrict our discourse on SDMA schemes to a
rudimentary discussion of the related research aspects inthe Decision-Directed Channel Estimation and Uplink
Detection Techniques for Multi-User SDMA-OFDM sections.
Having reviewed some of the basic OFDM-related transceiver functions, let us now provide a historical perspective
embedded in to a rudimentary overview of the more specificsystem design aspects in the next section.

Orthogonal Frequency Division
Multiplexing History
Early Classic Contributions
The first OFDM scheme was proposed by Chang in 1966[10] for inter-symbol interference-free (ISI) transmissions
over dispersive fading channels. During the early years of
the evolution of OFDM research various contributions dueto the efforts of Weinstein, Peled, Ruiz, Hirosaki, Kolb,
Cimini, Schüssler, Preuss, Rückriem, Kalet et al [10, 11,
15, 20, 25, 26, 16, 17, 18, 19, 21, 22, 27, 33] have to be mentioned. As unquestionable proof of its maturity, OFDM wasstandardised as the European DAB as well as DigitalVideo Broadcast (DVB) scheme. It constituted also a credible proposal for the recent third-generation mobile radio
standard competition in Europe. Finally, OFDM was also
selected as the European High Performance Local Area
Network’s (HIPERLAN) transmission technique as well aspart of the IEEE 802.11 Wireless Local Area Network(WLAN) standard.
As it was portrayed in Figure 1, the system’s operational
principle is that the original bandwidth is divided into ahigh number of narrow sub-bands, in which the mobile
channel can be considered non-dispersive. Hence no channel
equaliser is required and instead of implementing a bank of
sub-channel modems, they can be conveniently implemented with the aid of a single FFT operation by transforming or
modulating a block of n subcarrier symbols in a single step,
as was shown mathematically in Chapter 2 of [3].
These OFDM systems—often also termed frequency division multiplexing (FDM) or multi-tone systems—have been
employed in military applications since the 1960s, for example by Bello [34], Zimmermann [11], Powers andZimmerman [12], Chang and Gibby [14] and others.
Saltzberg [13] studied a multi-carrier system employing
orthogonal time-staggered quadrature amplitude modulation (O-QAM) of the carriers.
The employment of the DFT for replacing the banks ofsinusoidal modulators and demodulators was suggested by
Weinstein and Ebert [15] in 1971, which significantly
reduces the implementation complexity of OFDM modems.
In 1980, Hirosaki [33] suggested an equalisation algorithm
in order to suppress both intersymbol and intersubcarrierinterference caused by the channel impulse response or by
November 2004 ❖ IEEE Vehicular Technology Society Newstiming and frequency errors. Simplified OFDM modem
implementations were studied by Peled [16] in 1980, while
Hirosaki [17] introduced the DFT-based implementation ofSaltzberg’s O-QAM OFDM system. From Erlangen
University, Kolb [18], Schüssler [19], Preuss [21] andRückriem [22] conducted further research into the application of OFDM. Cimini [20] and Kalet [27] published analytical and early seminal experimental results on the performance of OFDM modems in mobile communications channels.
More recent advances in OFDM transmission were presented in the impressive state-of-the-art collection of works edited by Fazel and Fettweis [35], including the research by
Fettweis et al at Dresden University, Rohling et al at
University of Hong Kong, Vandendorp at Loeven University,
Huber et al at Erlangen University, Lindner et al at Ulm
University, Kammeyer et al at Bremen University and Meyret al [36, 37] at Aachen University, but the individual contributions are too numerous to mention. Important recent
references are the books by van Nee and Prasad [38] as well
as by Vandenameele, van der Perre and Engels [39].
While OFDM transmission over mobile communications
channels can alleviate the problem of multipath propagation, it is by no means flawless. Hence, recent research
efforts have been focused on solving a set of inherent difficulties regarding OFDM, namely the peak-to-mean power
ratio, time and frequency synchronisation, and on mitigating the effects of the frequency selective fading channel.
These issues are addressed below with reference to the literature, while a more in-depth treatment is given throughout the book [3].
Peak-to-mean Power Ratio
It is plausible that the OFDM signal—which is the superposition of a high number of modulated sub-channel signals—may exhibit a high instantaneous signal peak withrespect to the average signal level. Furthermore, large signal amplitude swings are encountered, when the time
domain signal traverses from a low instantaneous power
waveform to a high-power waveform, which may results ina high out-of-band (OOB) harmonic distortion power, unlessthe transmitter’s power amplifier exhibits an extremely
high linearity across the entire signal magnitude range.
This then potentially contaminates the adjacent channels
with adjacent channel interference. Practical amplifiers
exhibit a finite amplitude range, in which they can be considered almost linear. In order to prevent severe clipping of
the high OFDM signal peaks—which is the main source of
OOB emissions—the power amplifier must not be driven tosaturation and hence the amplifiers are typically operated
with a certain so-called back-off, creating a certain ”headroom” for the signal peaks, which reduces the risk of amplifier saturation and OOB emission. Two different families ofsolutions have been suggested in the literature, in order tomitigate these problems, either reducing the peak-to-mean
power ratio, or improving the amplification stage of thetransmitter.
More explicitly, Shepherd [40], Jones [41], and Wulich[42] have suggested the employment of techniques which
aim for minimising the peak power of the OFDM signal by
employing different data encoding schemes before modulation. The philosophy of these data encoding schemes is thatthey employ specific block codes for encoding the modulating data symbols by concatenating appropriate redundantsymbols, which mitigate the associated peak of the modulated signal. In other words, the legitimate crest-factor
reduction code words exhibit low crest factors or peak-to-7

mean power envelope fluctuation. Müller [43], Pauli [44],May [45] and Wulich [46] suggested different algorithms forpost-processing the time domain OFDM signal prior toamplification, while Schmidt and Kammeyer [47] employedadaptive subcarrier allocation in the spirit of [3], where theallocation of modulating bits was also minimising theresultant crest factor. Dinis and Gusmao [48, 49, 50]
researched the employment of two-branch amplifiers, where
each amplifier was fed with a near-constant-envelope signal, while the clustered OFDM technique introduced byDaneshrad, Cimini and Carloni [51] employs a set of parallel partial FFT processors in conjunction with separate associated transmitting chains. OFDM systems with increased
robustness to non-linear distortion have also been proposedby Okada, Nishijima and Komaki [52] as well as by Dinis
and Gusmao [53]. These as well as range of other crest-factor related aspects of OFDM transmissions were treated in
substantial depth in Part 2 of [3].
Synchronisation
Time and frequency synchronisation between the transmitter and receiver are of crucial importance as regards to theperformance of an OFDM link [54, 55]. A wide variety oftechniques have been proposed for estimating and correcting both timing and carrier frequency offsets at the OFDM
receiver. Rough timing and frequency acquisition algorithms relying on known pilot symbols or pilot tones embedded into the OFDM symbols have been suggested for example by Classen [36], Warner [56], Sari [57], Moose [58], as
well as by Brüninghaus and Rohling [59]. The philosophy ofthese pilot-based methods is that they allow the receiver toestimate the associated change of phase imposed by thechannel as well as by the timing- and frequency-differencesof the transmitter’s and receiver’s oscillators. Once the composite mis-adjustment has been estimated, it may also bereadily compensated. Frequency and timing fine-tracking
algorithms exploiting the OFDM signal’s cyclic extension
were published by Moose [58], Daffara [60] and Sandell [61],where it was exploited that the phase-change across the
OFDM symbol’s duration imposed by the time-delay alone isknow. If the actual phase difference deviates from theexpected difference, this may be deemed to be the consequence of oscillator frequency- or phase errors and hence
may be compensated. A range of OFDM synchronisation
issues constitutes the subject of Chapter 5 in [3].
Hybrid OFDM, CDMA and MC-CDMA Systems
Combining multi-carrier OFDM transmissions with CodeDivision Multiple Access (CDMA) allows us to exploit the
wideband channel’s inherent frequency diversity by spreading each subcarrier’s modulating symbol across multiple
subcarriers. As mentioned before, the attraction of this operation is that even if a subcarrier and the corresponding chipof the spreading code mapped to it is obliterated, the spreading code and the corresponding original unspread symbol
may still be recoverable. Furthermore, upon using uniqueuser-specific spreading codes the system is also capable ofsupporting multiple users. This technique has been pioneered by Yee, Linnartz and Fettweis [62]; by Chouly, Brajal
and Jourdan [63]; as well as by Fettweis, Bahai and Anvari[64]. Fazel and Papke [65] investigated convolutional coding
in conjunction with OFDM/CDMA. Prasad and Hara [66]compared various methods of combining the two techniques,
identifying three different structures, namely MC-CDMA[3], Multi-carrier Direct Sequence CDMA (MC-DSCDMA)[3] and Multi-tone CDMA (MT-CDMA). Like classic

8

unspread OFDM transmission, the various OFDM/CDMA
methods also suffer from high peak-to-mean power ratios,
which are dependent on the specific choice of the specific frequency domain spreading scheme employed, as investigatedby Choi, Kuan and Hanzo [67] and in Part 2 of [3].
Pilot-Aided Channel Estimation
The effects of the transmission channel manifest themselvesin that the transmitted OFDM signal is convolved with the
CIR, or when interpreted in the frequency-domain, it is multiplied by the frequency-domain channel transfer function(FDCHTF). At the receiver these channel-induced linear
distortions have to be removed, which is typically carriedout by estimating the FDCHTF and then multiplying thereceived signal with the inverse of the FDCHTF.
In recent years numerous research contributions haveappeared on the topic of channel transfer function estimation techniques designed for employment in single-user, single transmit antenna-assisted OFDM scenarios, since theavailability of an accurate channel transfer function estimate is one of the prerequisites for coherent symbol detection with an OFDM receiver. The techniques proposed in theliterature can be classified as pilot-assisted, decision-directed (DD) and blind channel estimation (CE) methods.
The simple philosophy of pilot-assisted frequencydomain channel estimation is that known pilot-symbols areallocated to the OFDM subcarriers at regular frequency
spacing. The pilot-spacing required for FDCHTF estimation
is determined by the rate of FDCHTF fluctuation versus thefrequency axis. More explicitly, these pilot subcarriers haveto facilitate adequate sampling of the FDCHTF H(n),requiring that the corresponding sampling frequency ishigher than the Nyquist frequency necessitated for thealiasing-free representation of the FDCHTF, as well as for
its recovery from these pilot-aided “Nyquist-rate samples” ofthe FDCHTF [3]. The frequency-separation between the
FDCHTF fades observed in Figure 2 depends on the maximum CIR duration observed for example in Figure 3, since
the CIR duration and the frequency-domain spacing of the
deep fades constitutes Fourier transform pairs. More explicitly, the longer the CIR, the more frequent are the FDCHTF
fades and vice versa.
The aforementioned OFDM symbol-by-symbol based
FDCHTF estimation approach may be rendered more efficient, potentially requiring a lower pilot overhead, if the
FDCHTF of consecutive OFDM symbols is predicted also as
a function of time, resulting in two-dimensional (2D) pilotaided FDCHTF estimation, as detailed in [3]. As in the context of the FDCHTF estimation versus frequency, therequired time-direction pilot-density is also determined by
the Nyquist theorem, this time obeying twice the Doppler
frequency encountered by the CIR taps, as it is illustrated
both graphically as well as mathematically in [3]. The family of pilot-assisted channel estimation techniques was also
investigated for example by Chang and Su [68], Höher[69–71], Itami et al [72], Li [73], Tufvesson and Maseng [74],Wang and Liu [75], as well as Yang et al [76–8]. Let us now
briefly consider the family of Decision-Directed Channel
Estimation (DDCE) schemes.
Decision-Directed Channel Estimation
By contrast, in the context of DDCE all the sliced andremodulated subcarrier data symbols are considered aspilots. Provided that there are no subcarrier decision errors,
the performance of DDCE may approach that of the perfectchannel estimation scenario. Phrased in more practical
November 2004 ❖ IEEE Vehicular Technology Society Newsterms, in the absence of subcarrier symbol errors and also
depending on the Doppler frequency-related rate of channel
fluctuation, it was found that accurate channel transfer
function estimates can be obtained, which may be of better
quality in terms of the channel transfer function estimator’smean-square error (MSE), than the estimates offered bypilot-assisted schemes. This is because the latter arrangements usually invoke relatively sparse pilot patterns.
More explicitly, the family of decision-directed channel
estimation techniques was investigated for example by van
de Beek et al [79], Edfors et al [80, 81], Li et al [82], Li [83],Mignone and Morello [84], Al-Susa and Ormondroyd [85],Frenger and Svensson [86], as well as Wilson et al [87].
Furthermore, the family of blind channel estimation techniques using no channel sounding pilots was studied by Lu
and Wang [88], Necker and Stüber [89], as well as by Zhou
and Giannakis [90].
In order to render the various DDCE techniques moreamenable to employment in scenarios associated with a relatively high rate of FDCHTF variation expressed in termsof the OFDM symbol normalised Doppler frequency, linear
prediction techniques well known from the speech coding literature [91, 92] can be invoked. To elaborate a little further,every FDCHTF sample may be predicted from a number ofconsecutive previous FDCHTF samples positioned at the
specific subcarrier frequency considered. However, in caseof, for example, 512 subcarriers, the same number of predictors would be required, which results in a high complexity. A computationally more efficient solution is to transformthe FDCHTF to the time-domain, yielding the CIR. Since
the CIR typically has only a low number of significant taps,
their prediction is computationally less demanding, even,when taking into account the complexity of the IFFT/FFT
operation required for generating the CIR and transforming
it back to the frequency-domain [82]. The general concepts
described by Duel-Hallen et al [93] and the ideas presented
by Frenger and Svensson [86], where a frequency domain
prediction filter-assisted DDCE was proposed, also contributed substantially to the literature of DDCE.
Furthermore, we should mention the contributions ofTufvesson et al [94, 95], where a prediction filter-assisted
frequency domain pre-equalisation scheme was discussed in
the context of OFDM. In a further contribution by Al-Susa
and Ormondroyd [85], adaptive prediction filter-assisted
DDCE designed for OFDM has been proposed upon invoking techniques known from speech coding, such as the
Levinson-Durbin algorithm or the Burg algorithm [91, 96,97] in order to determine the DDCE’s predictor coefficients.
Uplink Detection Techniques for Multi-user SDMAOFDM
Combining adaptive antenna-aided techniques with OFDM
transmissions was shown to be advantageous [3], for example in the context of suppressing co-channel interference incellular communications systems. Amongst others, Li,
Cimini and Sollenberger [98, 99, 100], Kim, Choi and Cho[101], Lin, Cimini and Chuang [102] as well as Münster etal [103] have investigated algorithms designed for multiuser channel estimation and interference suppression.
The related family of Space-Division-Multiple-Access(SDMA) communication systems has recently drawn wide
research interests [3]. In these systems the L different users’transmitted signals are separated at the Base-Station (BS)with the aid of their unique, user-specific spatial signature,
which is constituted by the P-element vector of channeltransfer factors between the users’ single transmit antenna
November 2004 ❖ IEEE Vehicular Technology Society Newsand the P different receiver antenna elements at the BS,
upon assuming flat-fading channel conditions such as thoseoften experienced in the context of each of the OFDM subcarriers. A whole host of Multi-user Detection (MUD) techniques known from the literature of CDMA communications
lend themselves also to employment in the context ofSDMA-OFDM on a per-subcarrier basis [3]. Some of thesetechniques are the Least-Squares (LS) [104–7], Minimum
Mean-Square Error (MMSE) [104, 105, 108–116],
Successive Interference Cancellation (SIC) [104–6, 111, 115,
117–121], Parallel Interference Cancellation (PIC) [104,122], and Maximum Likelihood (ML) MUD arrangements[104, 111, 115, 123–9].
Channel Estimation for Multi-user SDMA-OFDM
In contrast to the aforementioned single-user OFDM scenarios, in a multi-user OFDM scenario the signal received by eachantenna is constituted by the superposition of the signal contributions associated with the different users or transmit
antennas. Note that in terms of the multiple-input multipleoutput (MIMO) structure of the channel the multi-user singletransmit antenna scenario is equivalent; for example, to a single-user space-time coded (STC) scenario by using multiple
transmit antennas. For the latter a Least-Squares (LS) error
channel estimator was proposed by Li et al [130], which aims
at recovering the different transmit antennas’ channel transfer functions on the basis of the output signal of a specificreception antenna element and by also capitalising on theremodulated received symbols associated with the different
users. The performance of this estimator was found to be limited in terms of the mean-square estimation error in scenarios
where the product of the number of transmit antennas and thenumber of CIR taps to be estimated per transmit antenna
approached the total number of subcarriers hosted by an
OFDM symbol. As a design alternative, in [131] a DDCE wasproposed by Jeon et al for a space-time coded OFDM scenarioof two transmit antennas and two receive antennas.
Specifically, the channel transfer function1 associatedwith each transmit-receive antenna pair was estimated on
the basis of the output signal of the specific receive antenna
upon subtracting the interfering signal contributions associated with the remaining transmit antennas. These interference contributions were estimated by capitalising on theknowledge of the channel transfer functions of all interfering transmit antennas predicted during the (n – 1)-th
OFDM symbol period for the n-th OFDM symbol, also invoking the corresponding remodulated symbols associated with
the n-th OFDM symbol. To elaborate further, the difference
between the subtraction-based channel transfer function
estimator of [131] and the LS estimator proposed by Li et al
in [130] is that in the former the channel transfer functions
predicted during the previous, i.e. the (n – 1)-th OFDM symbol period for the current, i.e. the n-th OFDM symbol areemployed for both symbol detection as well as for obtaining
an updated channel estimate for employment during the (n+ 1)-th OFDM symbol period. In the approach advocated in[131] the subtraction of the different transmit antennas’
interfering signals is performed in the frequency domain.
By contrast, in [132] a similar technique was proposed by Li
with the aim of simplifying the DDCE approach of [130],
which operates in the time domain. A prerequisite for theoperation of this parallel interference cancellation (PIC)assisted DDCE is the availability of a reliable estimate of the
In the context of the OFDM system the set of K different subcarriers* channel transfer factors is referred to as the channel transfer function, or simply as the channel.

9various channel transfer functions for the current OFDM
symbol, which are employed in the cancellation process inorder to obtain updated channel transfer function estimates
for the demodulation of the next OFDM symbol. In order tocompensate for the channel’s variation as a function of the
OFDM symbol index, linear prediction techniques can be
employed, as it was also proposed for example in [132].
However, due to the estimator’s recursive structure, determining the optimum predictor coefficients is not as straightforward as for the transversal FIR filter-assisted predictor of
single-user DDCE, both of which are detailed in [3].
OFDM Applications
Owing to their relatively high implementational complexity
and crest-factor problems, OFDM applications have been
scarce until quite recently. During the late 1990s, however,
OFDM has been adopted as the new European DAB standard[23–6, 133] as well as for the terrestrial DVB system [57, 134].
For fixed-wire applications, OFDM is employed in the
Asynchronous Digital Subscriber Loop (ADSL) and Highbit-rate Digital Subscriber Loop (HDSL) [135–8] and it has
also been suggested for employment in power line communications systems [139, 140] owing to its resilience to bothtime dispersive channels and narrow band interferers.
Various OFDM applications were also studied within the

4th-6th European Framework Programme [141]. For example, an OFDM-based 155 Mbps WATM network was
designed by the so-called MEDIAN project in [142–5], while
the MagicWAND research consortium [146, 147] developed a
WLAN. Hallmann and Rohling [148] presented a range ofdifferent OFDM systems that were applicable to theEuropean Telecommunications Standardisation Institute’s(ETSI) recent personal communications oriented air interface concept [149].

Conclusion

This first article has provided a historical perspective of
OFDM/MC-CDMA multicarrier systems, identifying theirmost critical design aspects. These systems exhibit numerous attractive features, rendering them eminently eligible
for employment in next-generation wireless systems.The
following article will now focus on an OFDM/MCCDMA system design study, in an effort to contribute towards theresearch of next-generation systems.

References

References for this article are combined with references forPart II, and can be found starting on Page 15.
Author biographies can be found on Page 17

A Stroll along Multi-carrier Boulevard to Next-Generation
Plaza (II)—Space-Time Coded Adaptive OFDM & MCCDMA Performance Comparison
Lajos Hanzo, Byoung-Jo Choi, and Matthias Münster, School of ECS, University of Southampton
This companion article investigates a combined system constituted by a constant power adaptive modem employing spacetime coded diversity techniques in the context of both OFDM
and MC-CDMA. The combined system is configured to produce
a constant uncoded BER and exhibits virtually error-free performance when a turbo convolutional code is concatenated witha space-time block code. It was found that the advantage ofrendering the modem adaptive erodes when the affordable system complexity is less limited and hence the overall diversityorder may be increased.

Adaptive OFDM versus Multi-carrier CDMA

System Model and AOFDM Switching Levels
The family of OFDM-based multi-carrier systems [3, 4]
approach the theoretically highest possible 2Bd/Hz bandwidth efficiency quantified by Shannon, since they typicallyrequire only a small raised-cosine excess bandwidth for

10

Nyquist-filtering. Hence, they are considered attractive fordownlink wireless Internet services in future fourth generation (4G) systems as well as in high-speed Wireless Local
Area Networks (WLAN). However, OFDM in its basic formcannot fully benefit from the multi-path diversity potential of
wideband channels.
It was reported in the literature that the synchronisation requirement of MC-CDMA is within 10% of theframe length [150]. Thus, an MC-CDMA system having
the appropriate modem parameters constitutes an attractive downlink multiple access scheme for both fixed andslowly moving mobile terminals, where maintaining
near-synchronous operation is feasible. Since MC-CDMA
facilitates diversity reception similarly to a Rake receiver, the performance of single-user MC-CDMA is characterised by that of an ideal Rake receiver. In a multi-user
scenario joint-detection assisted MC-CDMA employing©IEEE

November 2004 ❖ IEEE Vehicular Technology Society News

transmission, BPSK, QPSK, 16-QAM and 64-QAM modes,
depending on the instantaneous channel quality perceived by
the receiver, according to the predetermined SNR-dependent
switching thresholds. It is assumed that the perfectly estimated channel quality experienced by receiver A is fed back totransmitter B superimposed on the next burst transmitted toreceiver B. The modulation mode switching levels of our
AQAM scheme determine the average BER as well as theaverage throughput. A set of optimum switching thresholds
was derived in [158] for transmission over flat Rayleigh fading
channels. However, AQAM modems employing these switching thresholds inevitably exhibit a variable average BER
across the SNR range, despite aiming for a given fixed target
BER, namely Bt. In order to achieve a constant target BER,
while maintaining the maximum possible throughput, a new
set of SNR-dependent switching thresholds was devised fortransmission over wideband channels [159, 160].
Figure 6 illustrates the switching levels optimised for both
adaptive OFDM and adaptive MC-CDMA for the target BER
of Bt = 10-3. The optimum switching levels decrease, as theaverage channel SNR increases and hence higher-throughput
modulation modes can be invoked more frequently. Figure 6
also shows the “avalanche” SNR, beyond which adaptive modeswitching is abandoned in favour of the fixed highest-ordermodulation mode, namely 64-QAM, since the BER of 64-QAM
satisfies the target BER requirement. The modulated symbol
is now space-time encoded. As seen at the bottom of Figure 5,
Alamouti’s space-time block code [161, 6] is applied across thefrequency domain. A pair of the adjacent subcarriers belonging
to the same space-time encoding block is assumed to have thesame channel quality. We employed the WATM channel modelof Figure 3 [4, p.476] transmitting at a carrier frequency of
60GHz, at a sampling rate of 225MHz and employing 512 subcarriers. Specifically, we used a 3-path fading channel model,©Wiley-IEEE Press, Hanzo, Münster, Choi, Keller [3].

the MMSE-BDFE [151] receiver approaches the singleuser performance.
When channel coding is employed in conjunction with frequency domain interleaving, OFDM substantially benefits
from the frequency domain diversity. However, OFDM may
not be capable of exploiting the diversity potential of the channel to the same extent as MC-CDMA, since in OFDM thechannel error statistics are more bursty than in MC-CDMA.
Hence, it is interesting to compare the coded BERs of OFDM
and MMSE-BDFE aided MC-CDMA in conjunction with concatenated turbo codes and space-time block codes over wideband Rayleigh channels.
Various combinations of Space-Time (ST) codes and channel codes can be used for transmission over wideband fading
channels [6, 152]. An attractive option is to use a half-rateturbo convolutional code concatenated to a space-time blockcode using two transmit antennas and to expand the signal
constellation to a higher order modulation mode in order tomatch the throughput of the system using no channel coding.
Another approach to maintaining a high effective throughput
is to use a high-rate turbo BCH code in conjunction with a ST
trellis code or ST block code and a lower order modulationmode, than in case of the half-rate FEC scheme. It was reported in [6, 152] that the former approach gives a lower BER,
than the latter. Hence, we will employ a half-rate turbo convolutional code in our comparative study.
As argued in the context of Figure 2 in Part 1 (This issue,
Page 4), wideband fading channels exhibit two-dimensional
channel quality variations, namely both time domain variation and frequency domain variation, and OFDM lends itself
to exploiting these two-dimensional channel quality variations[3, 153, 154]. In other words, both time- and frequency-domain
adaptivity can be simultaneously exploited in OFDM. By contrast, although capable of providing frequency domain diversity with the aid of averaging the channel qualities of several
subcarriers, MC-CDMA is less amenable to frequency domain
adaptation, than to time domain adaptation.
In order to contribute towards the next-generation system
studies, the aim of this second part is to compare the performances of space-time as well as turbo-coded adaptive
OFDM and MC-CDMA modems. Although adaptive coded
multi-carrier modulation systems have been extensively
studied [153, 155, 156], the effect of transmit diversity has notbeen considered.
Figure 5 portrays the stylised transmitter structure of our
prototype system. The source bits are channel coded by a halfrate turbo convolutional encoder [6, 157] using a constraint
length of K = 3 as well as an interleaver size of L = 3072 bits
and interleaved by a random block interleaver. Then, the
AQAM block selects a modulation mode from the set of no
Transmitter Chain

Source Bits

ChannelInterleaver

Turbo Conv.
Encoder

Adaptive
QAM

Multi-carrier
Modem 1

Tx 1

Multi-carrier
Modem 2Tx 2Space-Time
EncoderSpace-Time Block Coding over Subcarriers
Tx 1
x1

x2

x3

x4

x5

x6

x2

x1

x4

x3

x6

x5

2

3

4

5

Tx 2
1
block 1

block 26

7frequency domain
subcarrier index

block 3Figure 5 Transmitter structure and space-time block
encoding scheme
November 2004 ❖ IEEE Vehicular Technology Society News

Figure 6 The optimum switching levels devised for thetarget BER of Bt = 10-3, when using 1 Tx antenna and 1
Rx antenna. The WATM channel model [4, p.476] isassumed for MC-CDMA. The switching levels for OFDM
were obtained for narrow-band Rayleigh channels,
which can be used for any multi-path profile, since
OFDM renders the dispersive channel non-dispersive
11©Wiley-IEEE Press, Hanzo, Münster, Choi, Keller [3].
Figure 7 Performance of uncoded five-mode AOFDM and AMC-CDMA. The target BER is Bt = 10-3 transmitting over
the WATM channel [4, p.476]. (a) The constant average BER is maintained for AOFDM and single user AMC-CDMA,
while “full-user” AMC-CDMA exhibits a slightly higher average BER due to the residual MUI. (b) The SNR gain of adaptive modems decreases as ST coding increases the diversity order. The BPS curves appear in pairs, corresponding
to AOFDM and AMC-CDMA—indicated by the thin and thick lines, respectively—for each of the four different ST code
configurations. The markers represent the SNRs required by the fixed-mode OFDM and MC-CDMA schemes formaintaining the target BER of 10-3 in conjunction with the four ST-coded schemes
where the average SNR of each path is given by, and eachchannel associated with a different pair of transmit andreceive antennas was assumed to exhibit independent fading.
Uncoded Adaptive System
The simulation results characterising our uncoded adaptive
modems are presented in Figure 7. Since we employed the
optimum switching levels of Figure 6, both our adaptive
OFDM (AOFDM) and the adaptive single-user MC-CDMA(AMC-CDMA) modems maintain the constant target BER of
10-3 up to the “avalanche” SNR value seen in Figure 6 andthen follow the BER curve of the 64-QAM mode. However,“full-user” AMC-CDMA supporting U = 16 users with theaid of a spreading factor of G = 16 and employing the
MMSE-BDFE Joint Detection (JD) receiver [151] exhibits aslightly higher average BER, than the target of Bt = 10-3
due to the residual Multi-User Interference (MUI) of theimperfect joint detector. Since we derived the optimum
switching levels based on a single-user system, the switching levels are no longer optimum, when residual MUI ispresent. The average throughputs expressed in terms ofBits Per Symbol (BPS) steadily increase and reach thethroughput of 64-QAM, namely 6 BPS. The throughput
degradation of “full” user MC-CDMA in comparison to thesingle-user scenario was within a fraction of one dB.

12

Observe in Figure 7(a) that the analytical and simulation
results are in good agreement, which we denoted by thelines and distinct symbols, respectively.
The effects of ST coding on the average BPS throughput are
displayed in Figure 7(b). Specifically, the thick lines represent
the average BPS throughput of our AMC-CDMA scheme,
while the thin lines represent those of our AOFDM modem.
The four pairs of hollow and filled markers associated withfour different ST-coded scenarios represent the BPS throughput versus SNR values associated with fixed-mode OFDM and
fixed-mode MMSE-BDFE JD assisted MC-CDMA.
Specifically, the right-most markers correspond to the 1-Tx / 1Rx, the second to the 2-Tx / 1-Rx, the third to the 1-Tx / 2-Rx
and the leftmost to the 2-Tx / 2-Rx scenarios. First of all, we
can observe that the BPS throughput curves of OFDM andsingle-user MC-CDMA are close to each other, namely within
1 dB for most of the SNR range. This is surprising, considering that the fixed-mode MMSE-BDFE JD assisted MC-CDMA
scheme was reported to exhibit around 10dB SNR gain at a
BER of 10-3 and 30dB gain at a BER of 10-6 over OFDM [3,67]. This is confirmed in Figure 7(b) by observing that the SNR
difference between the and markers is around 10dB, regardless whether the 4, 2 or 1 BPS scenario is concerned.
Let us now compare the SNR gains of the adaptive
modems over the fixed modems. The SNR difference between
November 2004 ❖ IEEE Vehicular Technology Society News

Turbo-Coded Fixed Modem
When channel coding is employed in the fixed-mode multi-carrier systems, it is expected that OFDM benefits more substantially from the frequency domain diversity than MCCDMA, which benefited more than OFDM without channel
coding. The simulation results depicted in Figure 8 show thatthe various turbo-coded fixed-mode MC-CDMA systems consistently outperform OFDM. However, the SNR differences
between the turbo-coded BER curves of OFDM and MCCDMA are reduced considerably.
Turbo Coded Adaptive System
The performance of the concatenated ST block coded andturbo convolutional coded adaptive modems is depicted in
Figure 9. We now applied a different set of switching levels,
namely the optimum set of switching levels designed for the
relatively high uncoded BER of 3 x 10-2, rather than 10-3,
which was then further reduced by turbo coding. More explicitly, this uncoded target BER was obtained from the relationship of the uncoded and the turbo coded BPSK modems
employing the same coding parameters over AWGN channels,
with the ultimate objective of obtaining a coded BER of lessthan 10-7 for our adaptive modems. However, our simulation
results yielded zero bit errors when transmitting 109 bits,
except for some SNRs, when employing only a single antenna.
Figure 9(a) shows the BER of our turbo coded adaptive
modems, when a single antenna is used. We observe in the figNovember 2004 ❖ IEEE Vehicular Technology Society News

©Wiley-IEEE Press, Hanzo, Ng, Keller, Webb [4].

the BPS curve of AOFDM and the fixed-mode OFDM represented by the symbol at the same throughput is around
15dB. The corresponding SNR difference between the adaptive and fixed-mode 4, 2 or 1 BPS MC-CDMA modem isaround 5dB. More explicitly, since in the context of the WATM
channel model [4, pp.476] fixed-mode MC-CDMA appears to
exhibit a 10dB SNR gain over fixed-mode OFDM, the additional 5dB SNR gain of AMC-CDMA over its fixed-mode counterpart results in a total SNR gain of 15dB over fixed-mode
OFDM. Hence ultimately the performance of AOFDM and
AMC-CDMA becomes similar.
Let us now examine the effect of ST block coding. The SNR
gain of the fixed-mode scheme due to the introduction of a 2Tx / 1-Rx ST block code is represented as the SNR difference
between the two right most markers. These gains are nearly
10dB for fixed-mode OFDM, while they are only 3dB for fixedmode MC-CDMA modems. However, the corresponding gains
are less than 1dB for both adaptive modems. Since the transmitter power is halved due to using two Tx antennas in the ST
codec, a 3dB channel SNR penalty was already applied to thecurves in Figure 7(b). The introduction of the second receive
antenna instead of the second transmit antenna eliminates
this 3dB penalty. Finally, the 2-Tx / 2-Rx system gives around
3-4dB SNR gain in the context of fixed-mode OFDM and a 23dB SNR gain for MC-CDMA, in both cases over the 1-Tx / 2Rx system. By contrast, the gain of the 2-Tx / 2-Rx scheme overthe 1-Tx / 2-Rx based adaptive modems was, again, less than
1dB in Figure 7(b). More importantly, for the 2-Tx / 2-Rx scenario the advantage of employing adaptive modulation vanishes, since the fixed-mode MC-CDMA modem performs aswell as the AMCCDMA modem in this scenario. Moreover, thefixed-mode MCCDMA modem still outperforms the fixedmode OFDM modem by about 2dB. We conclude that since thediversity-order increases with the introduction of ST block
codes, the channel quality variation becomes sufficiently low
for the performance advantage of adaptive modems to vanish.
This is achieved at the price of a higher complexity due toemploying two transmitters and two receivers.

Figure 8 Performance of turbo convolutional coded
fixed-mode OFDM and MC-CDMA over the WATM
channel of [4, pp.476]. JD MC-CDMA still outperforms
OFDM. However, the SNR gain of JD MC-CDMA over
OFDM is reduced to 1-2dB at a BER of 10-4
ure that the BER reaches its highest value around the “avalanche” SNR point, where the adaptive modulation scheme
consistently activates 64-QAM. The system is most vulnerable
around this point. In order to interpret this phenomenon, let
us briefly consider the associated interleaving aspects. For
practical reasons we have used a fixed interleaver length of L
= 3072 bits. When the instantaneous channel quality was
high, the L = 3072 bits were spanning a shorter time duration
during their passage over the fading channel, because they
were delivered by a six times lower number 64-QAM symbols,
than in case of BPSK symbols. Hence the channel errors
appeared more bursty, than in the lower-throughput AQAM
modes, which transmitted the L = 3072 bits over a longer
duration, hence dispersing the error bursts over a longer duration of time. The associated more random dispersion of erroneous bits enhances the coding power of the turbo code. On theother hand, in the SNR region beyond the ‘avalanche’ SNR
point the system exhibited a lower uncoded BER, reducing thecoded BER even further. This observation suggests that further research ought to determine the set of switching thresholds specifically and directly for a coded adaptive system.
Alternatively, adaptive threshold-learning techniques, such asthat proposed by Tang [162] have to be designed.
We can also observe that the turbo coded BER of AOFDM
is higher than that of AMC-CDMA in the SNR rage of 1020dB, even though the uncoded BER is the same. Thisappears to be the effect of the limited exploitation of frequency domain diversity in coded OFDM, compared to MC-CDMA,
which leads to a more bursty uncoded error distribution, hence
degrading the turbo coded performance. The fact that ST block
coding aided multiple antenna systems show virtually error
free performance corroborates our argument.
Figure 9(b) compares the throughputs of the coded adaptive modems and the uncoded adaptive modems exhibiting a

13

©Wiley-IEEE Press, Hanzo, Ng, Keller, Webb [4].
Figure 9 Performance of the concatenated ST block coded and turbo convolutional coded adaptive OFDM and MCCDMA systems over WATM channel of [4, pp.476]. The uncoded target BER is 3x10-2. The coded BER was less than
10-8 for most of the SNR range, resulting in virtually error free transmission. (a) The coded BER becomes higher nearthe ‘avalanche’ SNR point, when a single antenna was used. (b) The coded adaptive modems have SNR gains up to
7dB compared to their uncoded counterparts achieving a comparable average BER
comparable average BER. The SNR gains due to channel coding were in the range of 0dB to 8dB depending on the SNR
region and the employed scenarios. Each of the two distinctive
bundles of throughput curves corresponds to the scenarios of
1-Tx / 1-Rx OFDM, 1-Tx / 1-Rx MC-CDMA, 2-Tx / 1-Rx OFDM,
2-Tx / 1-Rx MC-CDMA, 1-Tx / 2-Rx OFDM, 1-Tx / 2-Rx MCCDMA, 2-Tx / 2-Rx OFDM and 2-Tx / 2-Rx MC-CDMA starting from the far right curve for the throughput values higher
than 0.5 BPS. The SNR difference between the throughput
curves of the ST-plus turbo-coded AOFDM and those of thecorresponding AMC-CDMA schemes was reduced compared tothe uncoded performance curves of Figure 7(b). The SNR gain
owing to ST block coding in the context of AOFDM and AMCCDMA was limited to about 1dB due to the halved transmitter power. Therefore, again, ST block coding provides limited
additional gains in the context of adaptive modems, sinceeither of these fading counter-measures is capable of mitigating the effects of fading.

target BER, whilst maximising the average throughput.
As expected, it was found that ST block coding reduces therelative performance advantage of adaptive modulation,
since it increases the diversity order and eventually
reduces the channel quality variations. When turbo convolutional coding was concatenated to the ST block codes,
near error-free transmission was achieved at the expenseof the halving the average throughput. Compared to theuncoded system, the turbo-coded system was capable ofachieving higher throughput in the low SNR region at thecost of higher complexity. The study of the relationshipbetween the uncoded BER and the corresponding coded
BER showed that adaptive modems obtain higher coding
gains, than that of fixed modems. This was due to the factthat the adaptive modem avoids burst errors even in deepchannel fades by reducing the number of bits per modulated symbol eventually to zero.

Conclusion[1]

This companion paper has provided a system design example
and characterised the achievable performance of OFDM/MCCDMA multicarrier systems.
Explicitly, the performance of ST block coded constantpower adaptive multi-carrier modems employing optimum
SNR-dependent modem mode switching levels were investigated. The adaptive modems maintained the constant14

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November 2004 ❖ IEEE Vehicular Technology Society News

Lajos Hanzo, FREng., received his first-class degree in electronics in 1976, his doctorate in 1983 and his DSc in 2004.
During his career in telecommunications he has held various
research and academic posts in Hungary, Germany and theUK. Since 1986 he has been with the School of ECS,
University of Southampton, UK, where he holds the chair intelecommunications. He co-authored 11 books totalling 8000
pages on mobile radio communications, published in excess of
500 research papers, organised and chaired conferences presented overview lectures and has been awarded a number ofdistinctions. Currently he heads an academic research team,working on a range of research projects in the field of wirelessmultimedia communications sponsored by industry, theEngineering and Physical Sciences Research Council(EPSRC) UK, the European IST Programme and the Mobile
Virtual Centre of Excellence (VCE), UK. He is an enthusiastic
supporter of industrial and academic liaison and he offers a
range of industrial courses. Lajos is also an IEEE
Distinguished Lecturer of both the Communications as wellas the Vehicular Technology Society and a Fellow of both the
IEE and IEEE (http://www-mobile.ecs.soton.ac.uk).
Matthias Münster was awarded the Dipl. Ing. degree by the
RWTH Aachen, Germany and after graduation he embarked

on postgraduate research at the University of Southampton,
where he completed his PhD in mobile communications on
2002. His areas of interest include adaptive multiuser OFDM
transmission, wideband channel estimation, multiuser detection and a range of related signal processing aspects. During
his PhD research he contributed over a dozen various research
papers and following the completion of his thesis he returned
to his native Germany, where he is currently involved in thedevelopment of sophisticated signal processing algorithms.
Byoung-Jo Choi received his BSc and MSc degrees inElectrical Engineering from KAIST, Korea, in 1990 and
1992, respectively. He has been working for LG Electronics,
Korea, since January 1992, where he was involved in developing the KoreaSat monitoring system, Digital DBS transmission system and W-CDMA based Wireless Local Loop
(WLL) system. He was awarded the PhD degree in Mobile
Communications at the University of Southampton, UK,
where he was a postdoctoral research assistant from 2001 to
2002. He is a recipient of the British Chevening Scholarshipawarded by the British Council, UK. His current researchinterests are related to mobile communication systems
design with emphasis on adaptive modulation aided OFDM,
MC-CDMA and W-CDMA.

VTS Board of Governors Meeting 17 May 2004
The VTS Board of Governors’ meeting met at VTC2004Spring in Milan, Italy, on 18 May 2004. Elected Board members Charlie Backof, Dennis Bodson, Tracy Fulghum James
Irvine, Tad Matsumoto, George McClure, Sam
McConoughey, Tom Rubinstein, Eric Schimmel, Gordon
Stüber, Ray Trott and Jim Worsham were present, alongwith J.R. Cruz (Jr. Past President), Harvey Glickenstein (VPLand Transportation), Jae Hong, Lee. Chair VTC 2003
Spring, Glenda McClure (Conference Coordinator), FotiniNiovi Pavlidou (Chair of the Greek Chapter), Tan F. Wong
(Editor of the Transactions on Vehicular Technology) and FuChun Zheng (Chair of VTC2006-Spring).
The minutes of the previous meeting of 7 February 2004
were approved.
Secretary’s Report: Tracy Fulghum reported that the electronic distribution of meeting handouts the week before themeeting, rather than copying over a hundred pages andsending it to the meeting venue, seems to have been successful and will continue.
Treasurer’s Report: George McClure reported that thesociety had approximately 4100 active members, with anadditional 1317 members in arrears. The IEEE is replacing
the Book Broker program with the Conference Publication
Program to take account of the fact that conference proceedings are now electronic. This will pay $25 per paper for solely IEEE conferences, or $12.50 for financially co-sponsoredconferences. Compared to the hard copy proceedings of VTC
the Book Broker programme used to purchase, the net effectwill be a reduction in conference revenue to the Society of
about $25k. The page budget for Transactions on VehicularTechnology is 2000 pages for 2005. The non-member subscription has been increased, but the number of subscriptions has fallen in line with the IEEE average, which meansthat overall income has fallen here too.
President’s Report: Charles Backof reported that theIEEE was currently conducting a survey of non-recurring
November 2004 ❖ IEEE Vehicular Technology Society News

society members (i.e., people who retained membership ofIEEE, but dropped society membership. The results would
be made available tot the society in due course. A request had
been received to technically co-sponsor the International
Symposium on Wireless System and Networks (ISWN) to beheld in April 2005 in Bahrain. The first symposium (thiswould be the second) had 70 papers. This was agreed.
After a review of verified roll calls for Board of Governors
meeting for the past three years, a Board member was identified as being in non-compliance with the requirements formeeting attendance as set out in the Society Bylaws. It was
decided that he will not be removed from the board, but will
be excluded from approval for the re-election slate.
Publications: Editor Tan F. Wong reported on Transactions
on Vehicular Technology. There has been a net gain of five
Associate Editors (6 have left their positions while 11 camein). The transactions will easily hit its budgeted 2000 pages,
with very few accepted papers in backlog. An effort is being
made to get Associate Editors to get manuscript cycle time
down. A six month deadline for manuscript revision is being
imposed to get lingerers out. The acceptance rate is 45% over
one year, with the number of average pages per paper at 10.
It was agreed to impose a mandatory overlength charge of$220 for papers over 8 pages, effective 1 July 2004.
A proposal was discussed for additional funds for administrative assistance in the editorial operations ofTransactions on Vehicular Technology. The funds are essentially for a half-time administrative assistant from the
University of Florida. After some discussion, the proposal
was agreed, with a ceiling of $30 000 per year, to be administered quarterly as a foundation donation to the University
of Florida, beginning (retroactively) 1 October 2003. There
was additional discussion with regard to the subscription
cost of Transactions. It was noted that paper copy plus electronic access was the only option for Transactions; there wasno separate option for electronic access only. It was therefore
19agreed to set the subscription rate for Transactions on
Vehicular Technology at $22 per year for electronic subscriptions and $45 per year for electronic plus paper subscription.
James Irvine gave a report on the VTS News. A number of
special issues are in the works, e.g. an issue on research inEurope. The VTS News is on track for becoming a magazineby 2006. The new two color processes are taking a lot of time
for translating diagrams, etc., and was agreed to increase thebudget by $7500 to allow graphic design support for the typesetting work.
Digital Archive: Two options were considered - an initialarchive of all early pre-1988 papers not already available
through Xplore, and with a second phase with all Society
papers, or to do everything at once. It was agreed to go forward with the all at once scheme.
Society Constitution: Dennis Bodson presented the proposed revisions to the Society Bylaws. Most of the revisions
are editorial. After some discussion, it was agreed not tochange Section III-5.0 and IV-4.0, which would have had theeffect of increasing the amount of time someone who had
served as president would have to wait before being eligible
again. The remaining changes were carried.
Membership Development: Roger Madden presented a
Membership Development Plan. It was agreed to raise theMembership Development budget from $10 200 to $20 000
per year, with a case-by-case approval for each action by thecommittee. It was agreed to offer free membership for theremainder of this year to attendees of VTC Spring 2004. Tad
Matsumoto was requested to come up with a Europe specificlist of Distinguished Lecturers to reduce travel costs.
Nominations Committee: A slates of ten candidates for elections for the 2005-2007 term of the Board of Governors elections
was agreed: Charlie Backof, Dennis Bodson, Tad Matsumoto,
Sam McConoughey, J.R. Cruz, Eric Schimmel, Jae Hong Lee,
Harvey Glickenstein, Vijay Bhargava, and Lajos Hanzo.
Standards: Dennis Bodson reported on Standards. As
SCC32 has officially dissolved, the VTS has taken responsi-

bility for that standard, and things seem to be runningsmoothly. There was also some discussion of increasing the
VTS’s presence in 3GPP and other standards groups.
Conferences & Meetings: Dennis Bodson reported on
VTC2004-Spring. Things are going well, and there is projected to
be a $30 000 surplus. The President thanked TPC Chair James
Irvine for his efforts in this Conference to a round of applause by
the Board and attendees of the meeting. Glenda McClure reported on VTC2004-Fall. Registration was ready to roll, and authors
needed to be notified, but otherwise the conference preparations
were going well. Regarding VTC2005-Spring Stockholm, a contract has been signed with Clarion Hotel. Jan Uddenfeldt wasnamed General Chair, while Jens Zander was named Technical
Program Chair. A contract has been signed with the local HotelIntercontinental for VTC2005-Fall in Dallas. W.C.Y. Lee andSteven Gray have been identified as TPC’s.
General Chair Fu Chun Zheng presented a report on
VTC2006-Spring in Melbourne. The working title of the conference is “VTC2006 May”, as it will be in the Southern
Hemisphere. The hotel has been selected, the Grand Hyatt
Melbourne. David Everett has been named as TPC, and the dateof the conference is 7-10 May 2006. There was some discussion
about the technical committee wanting full paper review for thisconference, as opposed to a paper summary review, as has been
the norm for VTC. Generally, in Australia, papers are valued lessif they appear in a summary reviewed conference. The President
suggested a meeting with George McClure, and the Board would
act on this at the September meetings.
The first Asia Pacific Wireless Communications
Symposium (APWCS), in January of 2004, was a success.
There were 61 registrants and about 33 papers. It is proposed that the second APWCS be held in August of 2005 in
Saporo City, Japan, to be chaired by Prof. Hatori, and theBoard agreed to provide technical support.
The next meeting of the Board of Governors will be at
VTC2004-Fall in Los Angeles on Tuesday, 28 September
2004.

42 Volts—The View from TodayThomas A. Keim, Massachusetts Institute of Technology
Editor’s Note: Thanks are extended to the Convergence
Transportation Electronics Association for permission toreprint this article from its Convergence 2004 Proceedings.
Copyright 2004 Convergence Transportation Electronics
Association. The Convergence Transportation Electronics
Association is an organization dedicated to the advancement oftransport electronics technology and the support of mathematics and science education.
A few years ago, the automobile industry agreed to adopt standards for a new voltage for the production and use of electrical
power. The perception was near universal that 14 Volts was at
the limits of its capability, and that 42 Volts would be adopted

20

in a rush. The universal perception was wrong. Since then,much of the auto industry has encountered hard financial
times. In a totally separate development, parts suppliers introduced innovations at 14 Volts, some of which a few years ago
were thought to require 42 Volts. Today, there are 42-Volt cars
and trucks for sale, but only at numbers far lower than necessary to begin to achieve economies of scale. But the factor thatcaused the industry to develop the 42-Volt standard, the growthof electricity use on motor vehicles, continues with no sign ofletup. Further, the true technical obstacles to adoption of 42 Volts
have been discovered and at least provisionally solved. The way
forward to cost-effective solutions for advanced automobiles isclearer today than it was in the past.
November 2004 ❖ IEEE Vehicular Technology Society News

Introduction

Throughout the history of the automobile, the average load on
the electrical system has been increasing, model year uponmodel year. The principal drivers of this trend have been theincreasing use of electric power to perform secondary vehicle
functions, which in earlier automobiles were performed byalternate means, and the increasing level of equipment on the
average automobile. Electric windshield wipers and electricradiator cooling fans are examples of the former class, and thenear-universal use of electric rear window defoggers is an
example of the latter class. There is no reason to expect that
this trend will not continue into the future.
For the most part, this evolution has been gradual, and theindustry has responded by installing more powerful electric
generators and larger batteries to service the gradually
increasing load. In the 1950’s, there occurred a conversion from
6-Volt to 12-Volt electrical systems, which made it possible toaccommodate the larger load more economically. At that time,
the automotive electrical system was much simpler than today,
and this transition took place quickly, and without much, if any,
increase in expense.
For well over a decade, visionaries within the industry havebeen questioning whether continued use of today’s 14-Volt system will be the most economical way to provide electric powerin the future. Even before 1990, SAE had organised a committee on Dual/Higher Voltage Electrical Systems [1]. By
1994, a series of workshops had begun at MIT, to address thepossible future of automotive electrical distribution [2]. The
successor to the workshops is the MIT/Industry Consortium
on Advanced Automotive Electrical/Electronic Components
and Systems (the MIT Consortium) [3]. One early product was
the proposal of 42 Volts as a standard for automotive generation and distribution [4].
Implicit in this search for a new distribution system was thesearch for a cost-effective solution. The principal reason thatthe industry chose to come together to propose a standard was
the belief that, by agreeing to a standard, parts complying withthe standard would be produced in large volume (compared to
the results for a company-specific, or proprietary, standard),
and that the large volume would encourage parts suppliers andproduce low component costs.
The case was made that future electrical components, processing higher levels of power and using semiconductors to control the primary component power flow, could be produced
more economically, if they were designed to operate at a higher
voltage [5].
Some argued that at the new voltage, power could be generated and distributed at a lower cost. Certainly, savings were
expected in the wire harness. And savings could be projected forthe generator, too.
Less expensive power generation and distribution to lessexpensive loads could result in a lower cost power system. Of
course, this outcome depends on the projected savings being
realised in both the pre-existing components being converted involtage and in the new components. It also requires that little
or no new equipment (components or functions not present in
the present system) be required for the new system.
Although some projected that the new voltage would be acost saving, the mainstream vision was never that the electrical system for a current production model would be made lessexpensive by adopting the new voltage. Rather, the goal was tomake it possible for a future automobile, with a higher installed
electrical load, to be made at lower cost than if the new voltage
were not available.
But whether the vision was a cost saving, or simply a costeffective way forward, auto companies and parts companies
November 2004 ❖ IEEE Vehicular Technology Society News

from all over the world endorsed the new standard. Many
established substantial internal development programs to produce parts for the anticipated new systems. A positive-feedback
instability developed. As each successive company announced a42-Volt development program, other companies would reconsider their plans, and frequently increase their commitment.
Expectations grew very high. The vision for the industry was ofa cost-effective technology upgrade. But for each individualcompany, 42 Volts became an opportunity for new profitableproduct lines, an imminent threat to existing products, or both.
But in late 2004, adoption of 42 Volts for most manufacturers is viewed as a contingent possibility, rather than as a firmplan. Most of the internally funded development programs
have been stopped. The possibility exists that automotive electrical systems will continue their evolution without widespread adoption of 42 Volts. At the very least, the introductionof 42 Volts will be far slower than was anticipated only a few
years ago.
This paper explores the reasons for this change of mind, anddiscusses the way forward from here.
Some of the potential obstacles to adoption of a new distribution voltage were apparent even as the proposal was being
developed. Still others became evident as work progressed todevelop the components of the planned new systems.

The Dual-Voltage Dilemma

One of the most important differences between changing distribution voltage now at the change of the millennium, compared to the 6-Volt to 12-Volt transition at mid-century, is therelative complexity of today’s auto electrical system. The total
number of electrical parts on a modern automobile, and thefraction of the total vehicle cost that they represent, bears nocomparison to the first 12-Volt cars. Setting aside for the
moment questions of technical feasibility, the act of developing
a new part to functionally replace every electrical part on amodern automobile, even if the only difference in the new partis the input voltage, represents a monumental undertaking. It
is far from clear that the non-recurring design and qualification
expense could be economically recovered over the production
life of a single vehicle platform.
To avoid this massive conversion expense, most parties
considering a new distribution voltage have proposed dualvoltage systems. In these systems, the new loads that requireor benefit from the new voltage, are provided power at thatvoltage, while a second 12-/14-Volt system provides power tolegacy loads.
The adoption of a dual-voltage system quickly leads to anumber of other system choices. Clearly, if there are loads at
two voltages, there must be a power source at each voltage.
Prime choices are a dual-output alternator and a DC/DC converter operating between the two voltage buses. Because thecost of each power source depends on its peak power, one isquickly lead to conclude that a dual-voltage system should use
a battery at each voltage, to allow the power source to be sized
only for the average power at that voltage.
Vehicle designers look at the resulting system, with two batteries and dual power sources, and conclude that this represents an unsatisfactory solution, certainly for the long run.
Some manufacturers have at times suggested that they would
not build dual-voltage systems. But in most cases, the dualvoltage solution has been accepted at least as a short-term solution, while most makers planning or producing 42-Volt dualvoltage autos envision going to a single-voltage solution atsome point in the future.
With more detailed analysis, this seemingly understandable
goal is not as clearly desirable as it may seem. Some loads

21

(incandescent filament lamps prime among them) do not scale
well to higher voltages. A designer charged with eliminating all
lower voltage loads must either do without incandescentlamps, or, alternatively, arrange to operate lamps in series
strings, probably with some burnout protection circuit. It has
been demonstrated that lamps can be successfully operated
from 42 Volts using a relatively simple PWM control circuit.
The cost, weight, and inefficiency of the potentially numerous
PWM lamp controls must be weighed against the cost andweight of a potentially small battery and a voltage source,which itself probably comprises some form of a PWM circuit,
most probably more complicated than the simple lamp driver.
The need to use dual voltage is thus seen as a necessary cost
penalty for 42 Volts, at least in the short term, and probably fora very long time.

Technical Challenges for 42 Volts

In the years since the possible need for a higher distribution
voltage has been established, investigators have identified anumber of ways in which 42-Volt or dual-voltage systems are
qualitatively different from 14- Volt systems. Each of these differences requires consideration at the system engineeringlevel, and most require some additional features in the new bus
architecture, which add to cost but not to end-user function. So
cost-effective solutions to these technical challenges are
required for 42-Volt or dual-voltage systems to succeed.
Electric Arcs
By far the most pervasive difference between 14 Volts and 42
Volts is the behaviour of electric arcs. At 14 Volts, with all common materials of construction for automobiles, arcs are inherently unstable. If a circuit is interrupted, for example by a relay
or switch, an arc will occur, but it will persist only as long as an
inductive (L di/dt) voltage exists to sustain it. When the voltage
across the arc falls to or below 14 volts, it self-extinguishes.
At any voltage much above 14 Volts, certainly at 42 Volts, anarc between two electrodes separated by a small gap is stable;
it can theoretically burn indefinitely. There is an exception tothis statement; for very small currents, arcs exhibit unstable,
self-extinguishing behaviour at 42 Volts. In practice, arcs do notburn indefinitely. Most often, the process that caused the electrodes to be separated does not stop, causing the electrode gap
to increase with time. At a long enough gap, the arc becomes
unstable and self-extinguishes. In extreme cases, the melting of
the electrode is the process that lengthens the gap until extinction occurs.
This difference in behaviour can, in unfavourable cases,
result in dissipation in electric arcs which is much greater at 42
Volts than is possible at 14 Volts.
Although this problem had been recognised by several companies, it was not widely discussed in public until it was
brought to the attention of the MIT Consortium by Yazaki in
1999. The subsequent public investigation quickly defined andbounded the problem.
The Videos—The issues of electric arcs at 42 Volts has
been dramatised by the existence and frequent showing of anumber of very dramatic videos. Some of these videos make arc
welding look tame by comparison, and truly remarkable component damage is sometimes shown. These videos have been
responsibly prepared and presented within the automotive
electrical systems community, but their adverse impact on thelarger automotive community may have improperly damaged
the image of 42 Volts. Almost without exception, these videos
present the consequences of failing to consider arcs in thedesign of 42-Volt systems. They are examples of bad design,
and in extreme cases negligently bad design. There are far

22

fewer videos and before-and-after photos of the consequences ofgood and responsible design.
The fact is that the possibility of arcs must be considered in
the design of 42-Volt systems, and the possibility of arcs limits
the applicability of 14-Volt parts at the new voltage. But thepossibility of arcs does not make it impossible to design safe
and cost-effective 42-Volt systems.
Fuses—One of the earliest findings in the investigation of
42 Volts was that existing automotive fuses could not be used.
At 42 Volts, 14-Volt fuses fail dramatically, with an arc persisting for some time within the fuse body before eventually extinguishing, and frequently with the fuse body bursting intoflame. Much to their credit, the automotive fuse industry,
despite being very small and lightly capitalised by industry
standards, rolled up their sleeves and developed new designs
that did work satisfactorily [6]. These new fuses are compatible
with present production practice, and samples quickly became
widely available. The apparent ease with which the industry
dealt with the 42-Volt fuse problem may have set expectations
which suppliers of other parts could not so quickly meet.
Switches and Relays—The problem of 42-Volt arcs is not
so severe in switches and relays. The designers of these components have control over how fast their contacts separate,
and they have the option of putting more than one set of contacts in series. So it is fairly straightforward to design a switch
or relay for 42 Volts. Of course, switches and relays designed
for 14 Volts are unlikely to be satisfactory at the new voltage,
unless they are switching loads below the threshold current
for unstable arcs.
Connectors—Connectors are another matter. Most connectors are not intended to be mated and unmated under load.
But at 14 Volts, the practice has no practical adverse consequences, so it has become widespread in the repair industry.
But at 42 Volts, the consequences can be significant. Even asingle disconnection under load can render a connector unsuitable for further service. With few exceptions, the connector
designer cannot control the rate at which the contacts separate;that is generally determined by the service technician. So theprincipal design remedy available for switches and relays does
not apply to connectors.
The industry has not selected a standardised response to
the need for 42-Volt connectors. In part, this is due to there
being no single clearly superior choice, but in part it is also due
to a diverse range of reasonable choices. A strong case can bemade for abandonment of the practice of mating or unmating
connectors under load. The provision of a single, accessible
master switch could make this change easily acceptable.
Alternatively, selective application of special connectors
could be used. Many loads at 42 volts can be connected or disconnected under power with no more consequence than at 14
Volts, because their currents fall below the threshold. Only a
few loads may need special treatment, and for these, the industry has demonstrated a range of practical choices. A sense pin
can break before the power pins on disconnection, and thesense pin break can drive a relay that disconnects the circuit.
Some connectors introduce a resistance in series with the load
before the final contact parts. And in one case, a very promising contact alloy selection reportedly offers damage free mating
and unmating under a range of conditions covering many practical loads [7]. Few if any of these technologies are in parts catalogues today, but the way forward to cost-effective, arc-insensitive connectors seems to be open.
Parallel Arcs—In addition to switches, relays, and connectors, the difference in arc behaviour at the two voltages
requires consideration of the consequences of arcs at locations
where no arcs are anticipated. The first class of such arcs
November 2004 ❖ IEEE Vehicular Technology Society Newsoccurs as a result of faults to ground. Such a fault can occur
when an energised wire breaks and falls against the auto body,or when a portion of the body or frame cuts through wire insulation. These arcs are called parallel arcs, because they exist inparallel to the load.
Parallel arcs tend to be high current events. The source voltage is divided between the arc voltage, and voltage across the
impedance in series with the arc (including the source impedance). Most commonly at 42 Volts, a substantial portion of thesource voltage appears across the series impedance. For this tohappen, the circuit current must be many times the design current, and the most common consequence is that a fuse blows,
extinguishing the arc.
It is not uncommon for arc currents to be intermittent, evenwith nominally dc power supplies, and in the event of an intermittent arc, it is formally possible to dissipate much power in
the arc for a long period of time, without blowing the fuse. We
investigated this eventuality at MIT, and our observation wasthat this subclass, parallel arcs that do not blow fuses, was a
relatively small threat. The duty ratio of the intermittent current must be very low to prevent fuse blowing, so low that thisevent will represent only a very small fraction of cases. And,
with acceptable duty ratios and reasonable series impedances(values representative of an automotive wire harness), theresulting arc is not very energetic. In our experiments, we commonly saw melting of wire insulation and whiffs of smoke, but
only in the immediate vicinity of the arc. We did not see open
flame [8].
Series Arcs—The other class of unintentional arcs is seriesarcs. Here the arc occurs in a path that is in series with theload. Connector arcs are series arcs. Because the load is inseries, the arc current cannot exceed the load current, andfuses will not act. The most common place for a series arc is at
a connector, if not a connector being deliberately opened, then
one that has been improperly mated.
A series arc can be viewed as a member of a class of failures,
all of which comprise an unintended high impedance in series
with the load. Corroded connectors and partially but not totally severed wires are other members of this class. Any of thesefailures can cause a local dissipation of energy intense enoughto overheat and even to ignite the failure site. These failuremodes exist in today’s automobile fleet, and there is no protection against such failures in today’s automobiles. It is far fromapparent that the possibility of a stable series arc changes verymuch the overall risk to a vehicle from this class of faults, taken
as a whole.
Finally, it is possible to develop active circuitry that detects
an electric arc and disconnects the failed branch. Arc detection
is sufficiently cost-effective that it is used in the ac service in
new residences in many countries [9]. It is also now being marketed for electric power systems in transport category aircraft.
These both represent AC applications, but some of the same
suppliers indicate that DC arc detection can be performed, as
well [10].
Electric Arc Summary—Arc behaviour is demonstrably
different at 42 Volts than at 14 Volts. This difference can beused to make very dramatic videos. But the videos show cases
which cannot exist or should not be permitted to exist in a practical automobile. When a detailed circuit-by-circuit, failure-byfailure analysis is made, it is probable that the risk of damage
by arc is negligible or acceptable in the vast majority of cases.
For a few circuits and/or failure modes, new technology may berequired. For these cases, a range of cost-effective solutions
exists. In short, arcs are a new technical challenge for thedesigner, but they do not pose an insurmountable obstacle tousing 42 Volts in automobiles.
November 2004 ❖ IEEE Vehicular Technology Society News

Bus-To-Bus Faults
The dual-voltage automobile has a new failure mode, that of ashort between the high-voltage and the low-voltage buses. This
problem of course cannot exist without two voltages, but in adual-voltage automobile, it can be imagined to be relatively
common, as designers expect to feed some loads with both voltages, and to mix voltages within bundles of the wire harness.
A “hard” (low-resistance) short between the two supply voltages will almost certainly blow a fuse. But what happens afterthat depends on many factors. One cannot control in generalwhich of the two affected fuses will blow first and it can beestablished that there are many operating cases in which thesecond fuse does not blow.
In general, the requirement for a safe outcome should bethat both affected fuses clear. Some have argued that a final
outcome with 14 Volts applied through the short to a 42-Voltload is safe. This is defensible regarding the stress on the 42Volt component, but there is a hazard in that the short, while
being low enough in resistance to allow for fuse clearing, isstill a high enough resistance to produce hazardous local
heating.
A working group was formed in Europe by the Sci-worx
forum (which met originally under the German name Forum
Bordnetz, then later used the name Forum Vehicle Electric
System Architecture, and is now considering another namechange), to make recommendations concerning design for safety in light of the possibility of a bus-to-bus short. Their recommendation comprised a zonal protection concept, in which conductors at different potentials were kept separate [11].
More recently, work supported by the MIT Consortium
showed a simple, elegant design methodology that can guarantee clearing of both affected fuses by including simple active
elements in the fusebox. The cost to implement this methodology is modest [12].
A similar, less severe, problem occurs when a load is fed
from both voltages, using a common ground contact for both circuits. Should the ground contact be lost, the load is placed in an
unusual state. In general, this state need not be hazardous to
the load or the vehicle, but it is yet another failure mode to beconsidered during design.
In summary, the bus-to-bus short in dual voltage systems
presents a new failure mode. Design methods, either involving
vehicle layout or the inclusion of active elements in the fusebox,
have been proposed and evaluated. This obstacle has been adequately identified and studied, and suitable countermeasures
have been defined.
Corrosion
In 2002, an SAE Toptec included an important session in which
the performance of electrical parts, under electrical stress were
evaluated as a function of voltage in accelerated life tests in corrosive environments [13]. This session presented the independent, uncoordinated studies by a number of important contributors, but the independent works formed a surprisingly
coherent theme. Although the physics of the processes being
tested include many processes, including electromigration andsurface insulation degradation, the studies were generally
referred to as corrosion studies, and that name, although at
least partially misleading, is the one used here.
In general, the deterioration of the parts was troubling.
And parts tested at 42 Volts deteriorated substantially fasterthan parts tested at 14 Volts. But other than a general cautionthat one should be careful when using parts designed for 14
Volts at 42 Volts, it is hard to draw any conclusion from thissession, or from any other source which has come to theauthor’s attention.

23

Because the investigations were in almost every case accelerated tests, it is difficult to form any firm conclusion about thesuitability of any given part for a proposed service, other thanservice at 14 Volts in an automotive environment. The strengthof the accelerating functions is not known, nor is the threshold
between acceptable and unacceptable deterioration.
Compared to arcing or bus-to-bus faults, the state of knowledge and readiness of the automotive industry regarding thecollective phenomena referred to as corrosion at 42 Volts is not
far advanced. In part, this is the case because the system engineers who lead the early efforts understand the threats of arcing and faults, and are comfortable dealing with these problems. The perception has been that corrosion is “just a materials problem” and that suitable solutions can readily be found.
It is the author’s perception that the problem of “corrosion”
will not stand in the way of use of 42 Volts in automobiles.
Certainly trackless trolleys and streetcars work in exactly thesame environment as automobiles, using voltages far above 42
Volts, and with product lifetimes and duty cycles far in excessof the automotive standard. But the present state of uncertainty will prompt early adopters to design more conservatively
than the mature economic optimum, willingly incurring a probable penalty in system cost for a reduced risk of a systemic reliability problem. As experience is accumulated with parts working in the field at 42 Volts, unneeded conservatism will gradually be eliminated, and parts reflecting the true economic
optimum will emerge.

Present Status

The previous paragraphs summarise the remarkable workthat the automotive electrical community has done in finding,evaluating, and fixing the obstacles to application of 42 Volts. A
number of important, and sometimes fascinating, technicalproblems have been uncovered. In each case, one or more solution(s) have been found. Despite considerable searching, theindustry has not found a showstopper problem that would
derail the use of 42 Volts.
Yet the industry is at a standstill regarding this technology.
The reason is not technological: it is economic.
There are two economic challenges. The first is the financing of transition costs. This is not a new problem; it occurs withevery technological transformation, and the auto industry
solves it all the time. The second economic challenge is to identify the value that justifies the expense.
It is apparent that there is a cost required to implement 42
Volts. The source of cost is evident in a dual-voltage car, andeven in a pure 42-Volt application, parts which perform functions that are presently being adequately performed at 14 Volts
are likely to cost more, at least until volume builds to comprisea substantial fraction of the world’s production.
So the early vision of 42 Volts as a cost reduction has provento be unrealistic. But there is still the vision of 42 Volts as a
cost-effective way to get more electric functions on the vehicle
than is possible today.
To be selected on this basis, 42 Volts must be the only way,or the least expensive way, to get the required level of power
and function, and the cost must still be low enough so that thevehicle designer does not reconsider the specifications for
power and function.
The electric equipment market has changed to make itharder for 42 Volts to meet this selection criterion. Importantelectric functions including electric power steering and idlestop operation, have been introduced to the market as 14-Voltfunctions. (There remains some question whether the 14-Volt
implementations can be applied to the full range of light car
and truck sizes, but prototype idle-stop systems have been

24

demonstrated at 14 Volts even on large American V8
engines.) The output capability of automotive alternators has
been increasing. Electromagnetic engine valve actuation (animportant electrical load) has faded into the background, as
more advanced mechanical valve actuation systems are
implemented.
As it becomes possible to do more and more with 14 Volts,
the auto companies have strong incentives to put off adoptionof 42 Volts. Even if a given function can eventually be implemented less expensively at 42 Volts, the incentives are all negative for the early adopter. Each of the technical obstacles discussed above must be dealt with be any 42-Volt design. Withlimited experience with this new technology, a design error ismore possible for the first/early adopter. Risk of high warranty expense and/or reputation for low reliability and poor quality is high. Then too, the suppliers will look to recover much of
their investment in the technology in business dealings withearly adopters.
At present, there are few vehicles that need 42 Volts,
and there are powerful incentives not to rush to the newtechnology.
Just as each company to start a 42-Volt development program or to plan a 42-Volt product launch generated a flurry ofinterest and then activity among other companies, so has it
been the case that each company to abandon its plans causes
reconsideration at those companies which still have programs.
Either out of embarrassment, or in a desire to demonstratethat they have learned from their previous excessive enthusiasm, decision-makers may choose for their company to haveabsolutely no association with 42 Volts.
In late 2002, one manufacturer put the incremental cost ofa 42-Volt system, including only an integrated starter-generator, at between 555 and 1130 Euros [14]. The author concludes
that these costs are difficult to justify on the basis of increased
fuel economy.
Even in the face of such a negative outlook, there are two 42Volt vehicles in production, and a few more still being developed [15,16]. Evidently the long-term prospect remains attractive, even if the short term is not.

Future Prospects

Just as expectations were once unreasonably high, they are
now unreasonably low. The fundamental reasons for considering a voltage change are as sound as they ever were. There is
no let-up in the growth of electricity use in automobiles. If anything, with increasing adoption of electric power steering andidle-stop operation, the rate of growth is increasing.
The work that has been done in the past several years has
identified important differences between 42 Volts and 14 Volts,
which require that 42-Volt systems and their components bedesigned with an awareness of these differences. The goodnews is that we know that 14-Volt systems cannot be converted directly into 42- Volt systems. However, for each technicaldifference, we have good ideas how to proceed to design the 42Volt system.
Based on the work we have seen to date, 42 Volts will
require a cost premium, but with sound design, it is easy to
imagine that that premium will be 50 or 100 Euros, not ten
times that much. None of the technical challenges discussed
above require an expensive new direction.
50 Euros is still too much cost, just to have 42 Volts, but
so is even one Euro. But at 50 Euros, it is plausible to believethat some new capability may be enabled, for example, electric turbo boost, which produces an overall vehicle benefit
that exceeds the cost. It is also plausible that the voltagechange will permit cost reductions in other systems which
November 2004 ❖ IEEE Vehicular Technology Society News

may be specified on future cars, which can be implemented
at 14 Volts but are more economical at a higher level.
As both the unrealistic optimism of the past, and the pessimism of the present give way to realism in the future, we willcontinue to see more electricity use on automobiles. At somepoint, we may see some of that use migrate tot 42 Volts.

Conclusion

The idea of 42 Volts in auto electric systems has had in interesting and dynamic history. The whole idea is driven by theongoing growth in electricity use on motor vehicles, a trendthat continues and may be accelerating. About the year 2000, ahuge bubble of enthusiasm for 42 Volts resulted in activity allover the world. Investigators identified the important technicalquestions about application of 42 Volts in automobiles, andmade major progress toward finding answers. But as automakers planned to implement 42 Volts, two things happened. First,
with a few exceptions, they reconsidered their efforts and cancelled their programs. And second, the electric equipment market evolved so that applications that were once thought torequire 42 Volts can now be implemented at 14 Volts. (The second event may have contributed to the first.)
The bubble of enthusiasm came to be replaced with a widespread disillusionment. It is ironic, but when no one knew what
it took to implement 42 Volts, everyone was high on theprospect. But now that we know what it takes, and it is not that
bad, opinions are nearly uniformly negative.

References
[1]

[2]
[3]
[4]

[5]

“Activities of the SAE Committee on Dual/Higher Voltage
Vehicle Electrical Systems”, Hellman, J. Vincent andSandel, Robert J., SAE Paper No. 911652, Society ofAutomotive Engineers, Inc., Warrenton, PA, USA 1991.
Sidebar to “Automotive Electrical Systems Circa 2005”,
Kassakian, John G., Wolf, Hans-Christoph, Miller, John
M., and Hurton, Charles J., IEEE Spectrum, August 1996.
www.mitconsortium.org.
See, for example, the Draft International Standard“ISO/DIS21848.5 Road Vehicles – Electrical andElectronic Equipment for a 42V Network – Electrical
Loads”, International Organization for Standards,
Geneva, 2003.
“Semiconductor Technologies and Switches for New

Automotive Electrical Systems”, Graf, A., proceedings ofthe 7th EAEC European Automotive Congress,
Barcelona, 1999.
[6] “Impact of 42V Networks on Automotive Fuses”, Witt, B.,
and Scheele, J., Proceedings of the MIT Consortium
Meeting, Frankfurt, September 1999.
[7] “Arc-Proof Connector”, Hirai, H., Proceedings of the MIT
Consortium Meeting, Toulouse, October 2002.
[8] “Investigation of Electric Arcs in 42 Volt Automotive
Systems”, Wu, A., thesis, M.Eng. & S.B., Massachusetts
Institute of Technology, Cambridge, MA, USA 2001.
[9] “Applying and Using Arc-Fault Circuit Interrupters”,
Gregory, G., and Fanche, A. EC&M Magazine, Primedia,
Overland Park, KS, March 2004.
[10] w w w . t i . c o m / s n c / p r o d u c t s / c o n t r o l s /arcfaultoverview.htm, updated June 19, 2004.
[11] See, for example, “Working Party Short Circuit 42V”,
Report to Forum Vehicle Electric System Architecture,
Olk, J., June 27, 2002.
[12] “Developing Fusing Strategies for the 42-14V Fault in theDual Voltage System”, Shrivistava, R., Proceedings of the
MIT Consortium Meeting, San Diego, April, 2004.
[13] “42 Volt Challenges TOPTEC – Technical Potholes on the
Highway to Success”, Society of Automotive Engineers,
Troy, MI, USA, April 29-30, 2002.
[14] “Architecture of Vehicle Power Supply in the Throes of
Change – Requirements and Solutions”, Brinkmeyer, H.,proceedings of the Automobile Electronics Congress 2002,
Stuttgart, November 26, 27, 2002.
[15] “Development of the Toyota Mild-Hybrid System (THSM)”, Itagaki, K., Teratani, T., Kuramochi, K., Nakamura,S., Tachibana, T., Nakao, H., and Kamijo, Y., SAE Paper
No. 2002-01-0990, Society of Automotive Engineers,
Warrenton, PA, USA, 2002.
[16] “Powertrain Architecture and Controls Integration for
GM’s Hybrid Full-Size Pickup Truck”, Evans, D., Polom,
M., Poulos, S., Van Maanen, K., and Zarger, T., SAE
Paper No. 2003-01-0085, Society of Automotive
Engineers, Warrenton, PA, USA, 2003.
Thomas A. Keim is the Director of the MIT/Industry
Consortium on Advanced Automotive Electrical/Electronic
Components and Systems. He can be reached at tkeim@mit.edu.

Land Transportation
Harvey Glickenstein, Senior Editor
Seattle City Council approved funding for the South
Lake Union Streetcar project. The 2.6-mile line would be
funded by a tax on property owners along the route that is
expected to raise about $25 million supplemented by state andNovember 2004 ❖ IEEE Vehicular Technology Society News

federal money. No city general fund money will be used on the
project. Proponents of the line point to the successful streetcar
system in Portland, Oregon that is owned by the city but operated by Tri-Met, the operator of the light rail lines in Portland.

25Since the city is precluded under state law from operating atransit system, they may contract with Sound Transit, who iscurrently building a light rail line as well as operating commuter service in Seattle and a light rail line in Tacoma, to operate the Seattle streetcar line.

Map courtesy of Yarra Trams

Yarra Trams is extending the Melbourne tram network
to the Docklands area. The $A7.5 million extension will befrom La Trobe Street along Harbour Esplanade and Docklands
Drive to Central city Studios. Both the Route 48 and Route 30
trams will serve the new route. The 0.6-mile long extension is
expected to be completed by the end of this year.
This is the first modernization to take place since Yarra
Trams took over responsibility for the entire Melbourne tram
network on April 18, 2004.
In 1999 the Victoria State Government entered into contracts with Yarra Trams and with National Express Group

Australia (NEGA) to share operation of the tram network. One
company received the contract for the lines which were basically north-south and the other received the contract for thelines which were basically east-west, although there were portions where trams of both operators used the same tracks.
At the same time, the Victoria Government entered into
contracts with Connex and NEGA to share the operation of
the electrified commuter rail system. While an attempt wasmade to segregate the commuter rail operation as much as
possible, some sharing of track was required in this operation as well.
Each operator maintained its own rolling stock and maintenance of way, although the rolling stock was purchased by
the Victoria government. The fare system is a proof-of-purchase system using on-board validators on trams and buses
and station validators on the railroad network. A unified fare
instrument is used for all these operations. Maintenance ofMelbourne Tram Network.
26

November 2004 ❖ IEEE Vehicular Technology Society News

Map courtesy of Connex
Melbourne Commuter Rail Network.
the fare system for all the operations was contracted out toanother party.
In July, the Minister of Transport for the State of Victoria
announced an initiative to convert the current ticketing system
to a Smartcard system. The basic fare structure would remain
the same. It would still be possible to buy disposable
Smartcards on board trams and buses, as is possible with theexisting ticketing system. It would also be possible to re-loadvalue into prepurchased Smartcards. The call for tenders proposes that the new system will go into service in 2007 when theexisting fare system contract expires.
The savings expected to result from the privatization of
the two rail networks did not materialize. In 2002 NEGA
walked away from its two contracts and the Victoria
Government was required to hire a receiver to keep thetrains and trams running. After extensive negotiations
with Yarra Trams and with Connex, the Victoria
Government announced in February that it had reachedagreement for Yarra Trams to take over the entire tram
November 2004 ❖ IEEE Vehicular Technology Society News

network and for Connex to take over the entire commuter
rail network under new 5-year agreements that would

Las Vegas monorail27

Denver West Corridor Light Rail Extension
increase the original $A1.3 billion earmarked for these twosystems for the next five years to $A2.3 billion.
The Las Vegas monorail went into revenue service on
July 17. The new system connects nine casinos with theLas Vegas Convention Center and replaces a previous
system that only served one casino.
The system was built by Bombardier, who has a five-year
contract with two 5-year options to operate and maintain thesystem.
It is expected to be fully self-supporting financially. Fares
and advertising revenues are projected to cover operating andmaintenance costs as well as repayment of the tax-exempt nonrecourse revenue bonds that were floated to finance the $650
million project.
The line is fully automated. It initially operated from 8:00
AM to midnight. In August the system the hours were extend-

ed to 6:00 AM to 2:00 AM in August.
At press time the monorail was closed due to two separate
incidents of parts falling off the overhead vehicles. A reopening
date had not yet been announced.
Madrid ordered 70 Citadis Trams from Alstom for use
on two extensions totaling 20 miles. The trams will bedelivered starting in 2006 for use on the extensions that arescheduled to go into revenue service in 2007.
Denver received a Record of Decision from theFederal Transit Administration that the proposed
West Corridor Light Rail extension meets all of therequirements of the National Environmental Policy
Act of 1969. The project is a proposed extension of theexisting light rail line from Auraria West Station for 12.1
miles west to Golden Colorado.

Automotive Electronics
Bill Fleming, Senior Editor

DaimlerChrysler to Drop 42V System
Development

After years of hype, it appears that development of 42-volt
electrical systems may have hit a roadblock in the auto industry. At least that's the proclamation from DaimlerChrysler[1]. Stephan Wolfsried, vice president-electrical/electronics
chassis, for Mercedes Car Group declares the “42-volt systemis done with.” The demise comes as a result of cost and thelack of 42-volt components.
“Complexity involved during the transition phase from
14-volt to 42-volt would have been uncontrollable. Neither

28

are there 42-volt light bulbs, nor is it practical to transformthe power supply for every LED and every microprocessor
from a new 42-V standard, down to their present design
value of 14-volt,” Wolfsried said.

Other Daimler Chrysler Technology
Decisions

Wolfsried [1] laid down another ultimatum: “Mercedes-Benz
will not copy BMW's much-maligned iDrive instrument control system. Functions that nobody uses, and which benefit
nobody have no place in the car,” he said. He noted that inNovember 2004 ❖ IEEE Vehicular Technology Society Newsthe last year alone Mercedes had removed over 600 functions from its vehicles. Removed functions included, forexample, the tunnel air-circulation system, which was activated by pressing the air re-circulation button for two seconds. The system immediately would close the air re-circulation flap and open the windows and sunroof a few inches
to remove any contaminated or stale air that entered the car
after the car passed through a tunnel.
"CD-ROM and DVD-based navigation systems also will
be phased out in the next two years, because the discs tend
to warp at temperatures above 113° F (45° C)," said
Wolfsried [1]. DaimlerChrysler will switch to hard discs,
along with Smart Media and Personal Computer Memory
Cards as storage devices for future navigation systems. The
goal here is twofold: (a) to improve the overall ownershipexperience, while (b) reducing quality glitches. Mercedes
has been penalized of late in focus group studies because ofless-than-stellar electronics system reliability. Customers
complain that multiple buttons are confusing and systems
break repeatedly. Mercedes wants to put a stop to this andboost quality in the process.
Mercedes also is shifting from fiber-optic cable to conventional copper for many vehicle communications applications because of problems related to the fragility of the fiberoptic cables.

MY 2005 Cadillac STS to have Intellibeam& LED Tail Lamps

The MY 2005 Cadillac STS is equipped with an "intellibeam" system [2]. This system automatically switches
headlamps from high- to low-beam and back again whenoncoming headlamps or forward lighting elements aresensed. The system uses a CMOS light sensor mounted on
the back of the rearview mirror. The CMOS device
includes a miniature camera, light sensors and microprocessor that sense oncoming light and perform object
recognition. When the sensor detects an approachingvehicle’s headlights or preceding vehicle’s tail lamps, thesystem turns off the high beams gradually before it distracts other drivers. The system also detects and effectively ignores ambient light coming from streetlights, signreflections, buildings and other sources. In situations
where light from an approaching vehicle is more immediate, such as when cresting a hill, the system in that casereacts instantaneously, automatically and rapidly switching to low-beam.
Another lighting-related new technology involves the
Cadillac STS use of LED tail lamps which are designed withindirect optics, an industry-first application. Each tail lamp
incorporate 30 sources of illumination [2]. The use of indirect optics eliminates "pinpoints" of light normally associated with LEDs and enables an upscale, refined appearance
when illuminated. On the STS, each tail lamp has two vertical arrays consisting of 15 LEDs, and each LED has 20
optical facets. This configuration enables precise illumination and the design flexibility needed to meet domestic orexport requirements. The center high-mounted stop light on
the STS also uses LEDs, and is only 12-mm thick, and consists of 78 points of illumination. A novel lens design incorporates the use of pillow optics, which replaces the "pinpoint" appearance, normally associated with LEDs, with asmooth, refined output of light.

High Beam Hopes for LEDs

A new breed of brighter LEDs is being designed into vehicles. Two LED suppliers — Lumileds Lighting, San Jose,
November 2004 ❖ IEEE Vehicular Technology Society NewsCA; and Osram Opto Semiconductors, San Jose, CA — areworking on 100-lumen designs that would replace incandescent bulbs in light assemblies on a one-for-one basis (asopposed to the diode clusters now required to replace a single incandescent bulb) [3]. Visteon (Dearborn, MI), a tier-one
supplier, is currently talking to several automakers about
employing LED-based headlights as soon as the 2008 modelyear. For suppliers of automotive LEDs, the Holy Grailremains the headlight. Most suppliers expect to see the first
all-LED-illuminated vehicles reach the market within five
years [3].
"This is a monumental change for the auto industry," said
Jeff Erion, R&D manager for exterior systems at Visteon(which recently demonstrated a working LED-based headlight assembly [3]). "Since 1914, there has been only one
way to create light on a car. Now we're looking at a technology that can replace every filament bulb on the exterior of
every vehicle."Electronically Actuated Windshield Wipers

The rear-window wiper is used on many types of vehicles(minivans, vans, SUVs, etc.). A typical rear-wiper assembly consists of a unidirectional electric motor with a shaftmounted worm gear, a mating helical gear, and a mechanical crank mechanism. The crank mechanism createsreciprocating motion at the balance link, which translates
into a bidirectional, limited-angle rotation of the output
shaft. The traditional design has disadvantages of:mechanical complexity, multiple wear points, and inflexible performance (wipe angles and park positions are fixedby the linkage design).
Johnson Electric has developed a rear wiper without
using a mechanical mechanism [4]. An electronic control
unit directs four power MOSFETs that control power to thegear motor. Ramping-up the voltage to the motor at thestart of a wipe cycle, and down at the end of the cycle, provides soft start/stop operation.
Bidirectional wiping action is achieved without linkages by electrically reversing the direct-drive gear motor.
The wiper relies on a microprocessor to regulate system
motion by precisely controlling the motor’s speed, direction, and stroke. The motor uses a 16-pole magnet
attached to the motor shaft, and two Hall sensors that
send rotor position signals to a microprocessor. Costadvantages are obtained because one motor can now be
used for many vehicle platforms, and also provide vehiclespecific performance. The electronically actuated wiper
motor assembly gives a 40% reduction in mass, and a 20%
reduction in size over traditional mechanical wiper
assemblies [4].

140 Satellite TV Channels Transmitted to
VehiclesFirst, there were navigation systems using satellite guidance for cars. Then there was satellite radio. Now there issatellite TV with 140 channels available in your SUV, minivan or large sedan [5, 6]. Generally, to minimize distraction,
in-vehicle TV monitors are mounted so drivers can’t see
them. KVH Industries, a maker of mobile electronics, beganselling a satellite TV system called TracVision for installation in SUVs and minivans in September. The system
includes a large, roof-mounted, pancake-shaped antenna, 31
inches in diameter and 5 inches high. KVH's suggested selling price is $2,295. However, if you can wait — Delphi, XM
Satellite, Sirius, and Boeing are all working on more affordable, smaller-antenna, versions of satellite TV [5].

29Toyota Prius is Overrated …
…No, It Actually Does It All

According to an Automotive News writer [7], "engineers
have done a masterful job with the gasoline-electric Honda
Civic Hybrid and the Toyota Prius. Those cars are technicalmarvels, probably the most advanced and complex production cars ever made. But, although the Prius we test drove
had an EPA rating of 60 mpg city/51 highway, one of ourstaff members drove the Prius 331 miles in combined cityhighway driving and got just 40 mpg, while others recorded
44 mpg to 48 mpg in city driving and about 40 mpg on the
highway." The writer says, "I'd rather get an honest 50 mpg
with a diesel car and not have to worry about burning out
battery packs, or having a car with two powerplants — anengine and a motor — to maintain." He also agreed with
General Motors' reasoning: For vehicles sold in the UnitedStates, hybrid technology makes the most sense in the
biggest, gas-guzzling SUVs and other trucks.
On the other hand, according to Toyota’s rebuttal writer[8], "Yes, a conventional car can be as clean as the Toyota
Prius, and, yes, a diesel gets good fuel economy — in somecases as good as the Prius. Neither conventional gasoline
nor diesel can do both, however. The Prius can and does. The
Automotive News drivers said they recorded up to 48 mpg
city and about 40 mpg highway with the Prius. That's muchhigher fuel economy for a car in the same size class, at acomparable price, with similar performance, and creating
90 percent cleaner emissions on regular gasoline available
at any service station." The Toyota writer also states,"Overrated? Many motorists would disagree. The Prius has
no particulate emissions. Even the cleanest diesel cars are

not available in California or states adopting California's
supplemental emission standards because they cannot meetthe standards. In fact, non-California diesels are allowed
17.5 times more smog-forming emissions than a California
Prius. And finally, the Prius battery is designed to last thelife of the vehicle, and seven years of experience indicatethat nickel-metal hydride batteries are exceptionally longlived. In fact, all of the Prius' hybrid-related components,
including the battery, are covered for 8 years/100,000 miles(and 10 years/150,000 miles in California-standard states)."[Editor’s Note. “They report — You decide.” It looks likethe Automotive News writer [7] was comparing "apples andoranges," so I tend to agree with the Toyota writer [8]].

References
1.
2.
3.
4.
5.
6.
7.
8.

K. Kelly, “DC Dumps 42-Volts,” WARD’S AutoWorld,
p.9; June 2004
J. McCormick, “Technology With a Purpose,”
Automotive Industries, pp. 24-27; July 2004.
C. Murray, “High Beam Hopes for LEDs,” EE Times,
pp. 1, 14, 86; Aug. 23, 2004
D. Alexander, “Keeping It Clean and Smooth,” AEI(SAE Auto. Engr. Intl.), p.60; July 2004
J. Peter, “Cable In Your Car,” Automotive Industries,
pp. 30-31; July 2004.
E. Eldridge, “Satellite TV Beams 140 Channels Into
SUVs,” USA Today (newspaper), p. 2B; Aug. 27, 2004
R. Truett, “Civic Hybrid and Prius Are Overrated,”
Automotive News, p.14; May 10, 2004
I. Miller, “Prius Does It All: It’s Clean and Lean,”
Automotive News, p.14; May 24, 2004

Mobile Radio
Javier Gozalvez, Senior Editor

3G News

AT&T Wireless started in July offering customers in
Detroit, Phoenix, San Francisco and Seattle broadband
mobile wireless services with its launch of the first commercially-available true 3G UMTS network in the UnitedStates. The company also deployed its UMTS technology in
Dallas and San Diego later in September. The company said
it now offers the fastest nationwide wireless data service
with EDGE, and provides true 3G service in more U.S. markets than any other company. AT&T Wireless said its wireless broadband service provides customers with average
wireless data speeds between 220 and 320kbps, with bursts
up to 384kbps.
Sonera announced it will commercially launch, during
October 2004, its UMTS network in 20 locations in Finland.
The network will be further expanded according to demand.

30

The data transmission rate of the network is 384kbps at its
best. Sonera is also planning to introduce other technologies, such as EDGE.
T-Mobile has announced the launch of its UMTS datacards, combined with the extension of its Wi-Fi HotSpot
access points across the UK. Initially, the data cards will
give access to speeds of up to 128kbps although the company will progressively increase it to 384kbps. With the cards,
customers can have seamless roaming between GPRS and
3G, depending on the coverage available.
Vodafone claims to be the first operator in the
Netherlands to offer UMTS coverage to more than half of
the Dutch population, in particular 55%. Vodafone expects
to double the number of Dutch cities with Vodafone UMTS
coverage before April 2005. By means of a unique Vodafone
service, customers can determine whether the Vodafone

November 2004 ❖ IEEE Vehicular Technology Society News

UMTS network is active within a particular area or at a specific location. Based on postal codes, Vodafone's Customer
Services advisors can inform customers whether there is
Vodafone UMTS coverage in a specific area.
Huawei has announced it has succeeded in making thefirst WCDMA call in Tunisia, which it claims is also the first
WCDMA call in Africa. Through the execution of this project, Huawei is confident to provide an excellent WCDMA
network to serve World Summit on the Information Society(WSIS) in 2005. For the 3G pilot network, Huawei will provide the entire end-to-end UMTS solution, including UMTS
radio access network, core network, 3G mobile intelligent
network, 3G mobile data service platform and even 3G
handsets. For the UMTS system, Huawei will provide all
the equipment based on 3GPP R4 protocol. The core network is backward compatible with 3GPP R99 and GSM. The
coverage of the Huawei 3G network includes Tunis,
Hammamet and the highway between Tunis andHammamet.
Siemens together with Openwave Systems has supplied
a 3G/UMTS Video Mailbox System and a Video
Termination Gateway for the largest mobile operator in
Portugal , TMN. The subscribers will be able to record personalized video and audio greetings and retrieve recorded
video messages from missed callers with their video
enabled handsets. Furthermore, the 3G/UMTS Video
Termination Gateway allows real-time video communication between 3G/UMTS mobile terminals and fixed network terminals such as web cam-equipped PCs, 3G-324M
video terminals, and PSTN video phones. Openwave provides the voice and video messaging solution that is thebasis for the Video Mail System. This solution is an all-IP
content based management and Mx infrastructure
designed around the Voice XML standard.
Portelligent has released a study of UMTS handsets
which indicates that handset designers have substantiallyreduced the average complexity and manufacturing costs of
UMTS cellular phones over the past year. According to thefirm, the first generation of UMTS handsets, which supported both GSM and WCDMA, were plagued by high system complexity and high cost when they were introduced inEurope and Asia in 2003, as well as by consumer complaints
about product size and battery life. According to the findingsof "product teardown" analyses conducted by Portelligent on
11 UMTS handsets introduced over the past 18 months,
products that have appeared in the marketplace since thebeginning of 2004 reduce the average number of electronic
components found in the handsets by over 25%. The average
number of high-value ICs in the 2004 products – which area strong driver of overall manufacturing cost – has declined
almost 50%, as handset makers achieve more integrated
designs, and as semiconductor makers come to provide moremature chipsets and technology platforms for UMTS
phones. Portelligent claims that while UMTS phones introduced in 2003 substantially exceeded WCDMA/FOMA andhigh-end CDMA2000 products in average IC count and total
electronic component count, 2004 UMTS handsets bringoverall component count to a much more comparable level,
and have actually lowered average IC count below that of
the feature-rich FOMA phones that NTT DoCoMo has introduced in Japan this year. The 11 handsets analyzed in
Portelligent's UMTS study, which is entitled "The End of the
Beginning: Progress in Technology, Design, andManufacturing Cost in 3G UMTS Handsets", include models from NEC, Motorola, Nokia, Sony Ericsson, and LG.
Telstra has announced, in a network-sharing deal, that it
November 2004 ❖ IEEE Vehicular Technology Society News

will buy half of Hutchison’s 3G Australia network. The twocompanies will each continue to own separate core networks, application and service platforms. Telstra is planning to commercially launch its 3G services next year using
the entire network of more than 2000 base stations.
The UMTS Forum Chairman has indicated that 10 million people are already using 3G/UMTS networks anddevices to access a wide range of services. By the end of thisyear, it is expected to see as many as 70 networks operating
commercially. Mr Bienaimé said there has been an upturnin 3G/UMTS subscriber numbers since the early months ofthis year which coincides with a surge in network launchannouncements during Q1 and Q2, plus a wider choice of
attractively priced handsets from Asian, European and US
manufacturers. Commercially available on 46 networks in
24 countries, 3G/UMTS is supported by a growing choice of
WCDMA handsets and PC datacard products. More than 75
models have already been launched or announced.
NTT DoCoMo has announced that the number of subscribers to DoCoMo's 3G FOMA service surpassed the fivemillion mark in July, reaching the figure in less time than it
took to make the leap from three to four million subscribers
at the end of this past May. DoCoMo attributes the rapid
increase to the growing popularity of its latest 3G models in
the 900i series, as well as its enhanced service area. FOMA
service reached 99.7% of populated areas by the end of June.
The number of indoor base stations has increased to about
2000, which includes all subway stations within both theTokyo Metro and Toei subway networks. In addition,
DoCoMo began fixed rate data packet transmission service
for FOMA users on June 1, which offers users unlimitedaccess to i-mode mobile internet service.
Hutchison Italy has announced it has 1.5million clientsand expects to reach the year-end target of 2 million. The
operator has also said it can now reach up to 38million
Italians, that is two-thirds of the population.
Verizon Wireless has expanded its 3G wide-area
BroadbandAccess network to include 14 major metropolitan
areas and 24 airports across the United States. The
BroadbandAccess network allows large enterprises, smallmedium businesses and mobile professionals to conductbusiness anytime, anywhere in the BroadbandAccess-coverage area via a secure, true high-speed data connection withtypical user download speeds of 300-500kbps. The
BroadbandAccess network is based on CDMA2000 1xEVDO. Verizon Wireless commercially launched theBroadbandAccess service in July 2004.
Eurotel Praha, a wireless operator in the Czech Republic,
and Nortel Networks have launched what they claim is theindustry’s first CDMA2000 1xEV-DO network operating in
the 450 MHz radio spectrum. The network, which was
deployed across the Czech Republic in only four months,
now offers advanced data services for broadband Internet
access under the umbrella of "Eurotel Data Express". The
infrastructure was deployed on top of Eurotel’s existing
hardware to maximize the operator’s existing investment in
450 MHz spectrum and legacy network equipment.
VIVO and Motorola have launched a trial of Motorola’s
CDMA2000 1xEV-DO high-speed mobile broadband network solution on the carrier’s network in Curitiba (Brazil).
This 3G service will enable subscribers to experience highdata rates – at peak speeds of up to 2.4 Megabits per second(Mbps). For purposes of the trial, Motorola upgraded existing Motorola Base Transceiver Subsystems with the addition of a new Multi-Channel CDMA Module to enable
CDMA2000 1xEV-DO service.

31

Grupo Iusacell, a provider of cellular telephony products
and services in Mexico, has commercially launched 3G
CDMA2000 1X services and the first downloadable wirelessproducts and services based on Qualcomm's BREW solution
in Mexico.
Telecom Egypt and Huawei have announced the firstsuccessful CDMA2000 call at Fayoum province, a famoustravel destination in Egypt. Huawei provided end to end
CDMA 2000 equipments in the project, including
CDMA2000 core networks, radio access networks as well as
wireless terminals.
The CDMA Development Group (CDG) has announced
that the number of CDMA2000 subscribers worldwide has
exceeded 100 million. At the end of June, over 112 million
people across all continents used the technology.
CDMA2000 is used by 89 operators in 45 countries worldwide, with 36 more launches scheduled by the end of theyear. More than 650 CDMA2000 devices have been introduced to the market.
KDDI has announced that the total number of subscribers to its CDMA2000 1X service exceeded 15million in
July, just two years after its initial launch.
Alcatel has announced that the mobile network it has
deployed for Orascom Télécom Algérie enables the operator to introduce the first broadband EDGE services everprovided on the African continent. In the framework of a
supply contract, Alcatel deployed its end-to-end Evolium
solution, a multistandard platform designed for
GSM/GPRS/EDGE and 3G/UMTS networks.
3G Americas has announced that more than 100 operators in 63 countries from all regions of the world are in various stages of readiness for EDGE high-speed wireless datatechnology. Combined, these 108 operators represent hundreds of millions of customers in their current subscriber
base. In addition to the 28 operators offering commercial 3G
EDGE services to customers, there are 32 operators who are
actively deploying EDGE, 33 planned EDGE deployments, 8operators with EDGE-capable networks, and 7 other operators with EDGE networks reported in the trial phase.
EDGE has been commercially launched in four Asian countries, 10 countries in Europe and the Middle East, and even
Algeria, Africa.
In a new study, Analysys claims that some 3G operator
strategies may damage the economic prospects for 3G at
an early stage of its development. According to one of theauthors, head-to-head competition with xDSL and WLAN
could kill profitability. Instead, the firm recommends operators to find a more profitable way of co-existing withthese alternative solutions. The firm also thinks that operators moving away from volume-based 3G charging are
taking a big risk.

Technology News

The Ministry of Information Industry of China hosted aceremony to launch the country's first developed chip basedon TD-SCDMA standard. Spreadtrum Communication
unveiled what they claim is the world’s first GSM/GPRS/TDSCDMA chipset, and announced that the product will beready for mass production by the end of this year.
Samsung Electronics has unveiled the first-ever mobile
phone with an internal hard disc drive. The V5400 is
equipped with a 1-inch diagonal, 1.5GB hard disc drive that
greatly expands the memory capacity of mobile phones fromthe conventional 100MB maximum capacity.
NTT DoCoMo has announced the development of theN900iL, a dual network 3G FOMA handset that runs on

32

both FOMA and WLAN networks. The device may be used
as a standard FOMA handset, as well as an in-house VoIP
phone utilizing a company's internal WLAN network. As aresult, users can prioritize standby for incoming calls fromeither FOMA or the WLAN network, or set the handset on
dual mode to receive calls from both networks. The
Japanese operator has also announced it will invest in Texas
Instruments to jointly develop a single-chip LSI making
FOMA 3G handsets compatible with both W-CDMA and
GSM/GPRS networks. Currently, it is necessary to embed
two chips in order to produce a W-CDMA and GSM/GPRS
dual mode handset. Enhanced chipsets will also enable theupgrading of basic FOMA handset functions, such as longer
standby-time.
Nortel has unveiled a new high-capacity, high-density
base station, the GSM-UMTS Base Transceiver Station(BTS) 18000. The manufacturer claims that the BTS willallow operators to drive reduced operating costs by handlingup to 50% more voice and data subscribers per BS comparedto other commercial dual mode base stations currently
available. The BTS 18000 will provide a common radio platform for GSM and UMTS that will be scalable and spectrally efficient, and will improve network capacity while limiting the need for the costly cell splitting often used toincrease wireless network capacity. In addition, the BTS
18000 will be more compact because it will allow wirelessoperators to support both GSM and UMTS without needinga separate cabinet for UMTS. Wireless service providers will
be able to enhance BTS 18000 to support HSDPA without
hardware upgrades.
Nokia has announced the development of Nokia
MetroSite 50 BTS for the US market. Nokia claims it is theworld's smallest three-sector WCDMA base station whose
size and high-power radio frequency performance will offer
flexible deployment options in large and small coverage
areas. The flexibility offered by the BS is expected to yield
up to 30% in site and deployment cost savings.
Fujitsu Microelectronics has introduced a new chipset for
the high-sensitivity GPS/AGPS receivers. According to the
manufacturer, the chipset achieves the industry’s highest
levels of sensitivity, accuracy and Time-to-First-Fix (TTFF)
with low power and a small PCB footprint. The chipset supports GPS L-band C/A code and is capable of operating inboth "autonomous GPS/standalone" mode and "assisted
GPS" mode. It also supports leading air interfaces, including
UMTS/WCDMA, GSM/GPRS, PDC and CDMA.
Nokia has announced that the Variable-rate MultimodeWideband speech codec (VMR-WB), developed and characterized by 3GPP2/TIA, is ready for large-scale deployment.
According to Nokia, it is the first speech codec that is fullyinteroperable with 3GPP/AMR-WB, the standard in GSM
and WCDMA networks. The VMR-WB codec outperforms
the existing wireless and wireline codecs operating at thesame data rates and can be used in a variety of circuitswitched or packet-switched multimedia applications. The
algorithmic specification of VMR-WB standard has been
published by 3GPP2 and TIA as 3GPP2 C.S0052-0 v1.0 and
TIA-1016, respectively, and its software will be available
through these organizations and Nokia.
Intel has disclosed key technical details of its upcoming
WiMAX product, code named "Rosedale". The product is
expected to be the first "system-on-a-chip" design for costeffective customer premise equipment (CPE) that supports
IEEE 802.16-2004 (previously known as IEEE
802.16REVd). IEEE 802.16-2004, also known as WiMAX, isan emerging wireless standard that promises to provide
November 2004 ❖ IEEE Vehicular Technology Society News

broadband connectivity at DSL speeds across long distances. ntel has begun sending sample Rosedale product to
key customers. Rosedale will include the 802.16-2004 MAC
and OFDM PHY, an integrated 10/100 MAC, inline security
processing and a TDM controller interface which enables
applications such as broadband Internet streaming data
and voice. WiMAX Forum, an industry group chartered totest and certify interoperability among WiMAX products, is
expected to hold initial interoperability testing and certification programs in 2005.
picoChip has announced the availability of complete software implementations for HSDPA picocells and 802.16(WiMAX) basestations, the PC8218 and PC8520 respectively. Both "off the shelf" systems run on the company's PC102
picoArray DSP. The picoChip PC8520 WiMAX basestation
solution provides a software-defined implementation of the802.16-2004 PHY, for the 256OFDM mode with "carrierclass" reliability and performance. The PC8520 enables
basestations to be WiMAX-certified. The software upgrade
to 802.16e for mobility, including scalable PHY andadvanced FEC, will be available next year. The PC8218
HSDPA picocell replaces the company's previous reference
design by integrating the complex Iub interface, significantly reducing system BoM and simplifying integration.
NMS Communications has announced it is working with
Lucent Technologies to design and build an enhanced optical voice processor for wireless network operators building
3G networks. Advanced signal processing will improve callclarity and quality. NMS expects initial commercial deployment within a year.
Orange Switzerland has launched
Mobi-Click, a mobile phone equippedwith only three buttons. The Swiss-produced Mobi-Click is aimed at people looking for an easy-to-use mobile phone justto make calls, such as the elderly or disabled. The new handset allows such people to contact their family without having
to dial a number. The Mobi-Click is aplain mobile phone with three large buttons; for each one of the buttons, the mostimportant numbers are stored.
ntl's Broadcast division and O2 haveannounced the UK's first usability trialof multi-channel television to mobile
phones, beginning in spring 2005. Fromnine broadcast transmitters covering The Mobi-Click
120 square km around Oxford, the trial phone has only
will see 500 O2 customers provided with three buttons
a multimedia mobile phone with a builtin digital TV receiver. This will allow the participants toreceive a line-up of 16 TV channels. To carry out the trial
in the UK, ntl has joined forces with O2, Sony and Nokia,
that will make available their prototype DVB-H receiverdevices. ntl will develop the TV channel portfolio and will
design, build and operate the transmission network. The
trial will use the DVB-H broadcast transmission standard
for handheld devices, which is an efficient 'one-to-many'method of delivering content in a way that complements
the functionality of 3G.
Nokia and NEC have successfully completed the firstphase interoperability testing between the two companies'
IP Multimedia Subsystems (IMS). The testing program verified the functionality of major IMS features over an IP network connecting Europe and Japan. During the tests, Nokia
and NEC established sessions for voice over IP as well as
November 2004 ❖ IEEE Vehicular Technology Society Newstransferred instant messages between test terminals. IMS
enables both mobile and fixed devices to establish IP sessions between each other. Also Push to talk over Cellular,
the voice service for one-on-one and one-to-group communications, will work over IMS. Standardized in 3GPP Release
5, IMS is designed to allow service access and interoperability between operators and vendors. The trials are also being
used to look at issues related to roaming at the service level.
Racal Instruments Wireless Solutions (RIWS) claims tobe the first test equipment manufacturer to haveapproved test cases for use in the UMTS 1900 MHz 'FDD
Band II'. The test cases have been validated by the
Validation Competence Center of CETECOM, in Essen,
and include Inter-System Handover between 1900 MHz
UMTS and 1900 MHz GSM. The 6401 AIME/CT systemprovides the capability to run the standard UMTS protocol conformance tests, as defined in 3GPP TS 34.123 andimplemented in TTCN.
Radioplan has announced the release of WiNeS 3.1,
which it claims is the world’s first commercial simulationand optimisation toolset for the HSDPA standard, considered the evolution of WCDMA.

In-flight wireless services

Qualcomm and American Airlines have successfully
demonstrated in-cabin voice communications using commercially available CDMA mobile phones on a commercial
American Airlines aircraft. Through the use of an in-cabin
3G "picocell" network, passengers on the test flight wereable to place and receive calls. The proof-of-concept
demonstration flight originated out of the Dallas/Fort
Worth International Airport. During the approximate twohour flight, passengers were able to place and receive
phone calls and text messages on their mobile phones. A
small in-cabin CDMA cellular base station on the plane,that uses standard cellular communications, was connected to the worldwide terrestrial phone network by an air-toground Globalstar satellite link.
Airbus has also successfully completed an in-flight trial
using GSM technology, developed by Airbus in conjunction
with Icarelink. During the trial, calls and text messages
were sent and received during the flight without interferingwith the plane’s navigation systems. The calls were routed
through a picocell to a Globalstar satellite communications
network and then to a ground-based wireless network. The
companies also trialled Bluetooth, Wi-Fi and WCDMA.
Moreover, a medical emergency was simulated to show how
the system performed when some traffic has to be prioritised. Airbus has said it is planning to put in-flight mobile
phone technology on its aircrafts by 2006.
Malaysia Airlines will soon allow its passengers to send
and receive short text messages and short e-mails through its
In-flight Entertainment system. The company has decided toequip its Boeing aircrafts with SITA’s AIRCOM SMS facility.
The Association of Flight Attendants (AFA) is joining
forces with industry groups to develop and recommend standard practices to manage the use of wireless devices on aircraft in flight. Previously, the Consumer Electronics
Association (CEA) said it is working to enable mobile phoneusers to use their phones during the flights.
According to a research study conducted by Telenorand ARINC at the London Heathrow and Gatwick airports, nearly half of all international business fliers would
prefer to travel on airlines that allow the use of mobile
phones in flight. The two companies are marketing an
inflight GSM service.

33

Research NewsNTT DoCoMo has announced the joint development of a
prototype micro fuel cell for 3G FOMA handsets. The prototype, manufactured by Fujitsu Laboratories, is expected togreatly extend FOMA handset usage time once it goes into
commercial production. The micro fuel cell is aimed at meeting user demands for more convenient handsets withgreater power capacity, as well as reduced environmental
impact. The micro fuel cell is a standalone device shaped
like a cradle for recharging handsets. It generates electric
power by combining hydrogen and cheap, environmentallyharmless methanol to produce a chemical reaction.
Hydrogen ions are extracted from the air via a layer sandwiched between positive and negative electrodes. The prototype has the same basic specifications of other FOMA handset rechargers and will be compatible with all FOMA handsets. Further development of the prototype is expected to becompleted by the end of fiscal 2005.

Micro fuel cell for 3G FOMA handsets
mPhase Technologies and Lucent Technologies haveannounced a major milestone for future commercializationof a nanotechnology-based battery. Lab tests, which havebeen replicated, proves it is possible to fabricate nanotechbased batteries, which can store and generate electric current. The prototype battery is based on a Bell Labs discovery that liquid droplets of electrolyte will stay in a dormant
state atop microscopic structures called "nanograss" until
stimulated to flow, thereby triggering a reaction producing
electricity. The experiment proved that this superhydrophobic effect of liquids can permit precise control andactivation of the batteries on demand.
KDDI has announced an agreement with Toshiba and
Hitachi to cooperate on research to develop a compact fuelcell battery that can be used in mobile phones by the end of
2005. The research will cover areas such as miniaturization,ease of use and all technical considerations required forincorporating the batteries into mobile phones. The plans
are to complete an external, battery-charger-type model
within 2004 and a complete mobile phone with built-in
model by the end of the 205 fiscal year.
The National Institute of Standards and Technology(NIST) has awarded Carbon Nanotechnologies, Motorola
and Johnson Matthey Fuel Cells a $3.6 million grant todevelop "free standing" carbon nanotube electrodes for
micro-fuel cells in order to meet the ever-growing demand
for more power and longer run times in portable microelectronics.
Vodafone Netherlands is currently testing a handy
charger equipped with solar cells. The solar charger is a flatbox that contains a small solar collector. To be charged, thebox has to be unfolded, put into daylight and connected tothe mobile phone or PDA.
Strategy Analytics has predicted that the market for battery cells will exceed $9billion by 2010. The firm claims thatthe demand for small form factor fuel cells will be disap-

34

pointing and that the development of Lithium-sulfur batteries promises to double the capacity of traditional
rechargeable batteries. According to Strategy Analytics, thedevelopment of the fuel cell market will be inhibited by thelack of a suitable supply chain and restrictions on the carriage of methanol on public aircrafts.
At the "Mobile Internet 2010" forum held by the German
Ministry of Education and Research, Siemens presented a
test system where videos and music as well as a Microsoft
NetMeeting conference were transmitted in wireless modeat data rates of up to 360Mbps. To also achieve these peakdata rates for larger coverage areas, Siemens claims it is thefirst company to test a combination of orthogonal frequency
division multiplexing (OFDM) and the so-called multi-hop
technology, a new infrastructure concept. The system wasalready tested successfully in a field trial in the center ofMunich. The multi-hop concept can increase the signal coverage area considerably. Wireless but fixed multi-hop stations — a combination of base station, repeater and router— forward the signal from cell to cell, also around obstacles,
down to the terminal device when the direct link between
base station and mobile terminal is interrupted. To makethe high-frequency signals more resistant to interference,
Siemens deploys OFDM.
Motorola has claimed that, by combining results fromfield experiments and research conducted by Motorola Labs,
it has proven existing OFDM technology can support highspeed mobile networks with a peak downlink speed of up to
300Mbps. Motorola Labs recently completed a series ofmobile wide area broadband wireless field experiments
using OFDM on a 20MHz bandwidth channel with multiple
antenna handheld devices. Applying data from the field
experiments in laboratory tests, Motorola Labs validated
that a 20MHz mobile OFDM channel can support peak
uncoded channel data rates of up to 300Mbps. The fieldtests were conducted in the greater Chicago area in bothurban and suburban environments. In the field tests
Motorola Labs attained data throughputs exceeding
20Mbps with a latency of just 25milliseconds while simultaneously demonstrating real-time applications and travellingat typical highway speeds (in excess of 100km/h or 62mph).
Flarion Technologies has announced that T-Mobile has
deployed a trial of Flarion’s system for mobile broadband
services in the Hague (Netherlands). T-Mobile has been testing FLASH-OFDM since 2003 and will now collect data on
usage and customer behaviour. During the trial, users will
experience a mobile data service of around 1Mbps capable ofbursting to 3.2Mbps in the downlink and 30-50kbps in the
uplink, bursting to 90kbps.
The National Taiwan University (NTU) is collaboratingwith eASPNet Taiwan and Nortel Networks to commencetrials of a new Nortel Networks Wireless Mesh architecture
designed to extend the reach of WLAN technology. This newarchitecture enables wireless broadband connectivity forenterprises and end-users with indoor and outdoor access.
Nortel Networks Wireless Mesh Network solution uses
wireless links to connect the access points, allowing enterprises or service providers to install WLANs with a minimal
amount of Ethernet cabling or other backhaul facilities inareas where network limitations make it cost -prohibitive to
use traditional wired access points. The company claims
that this innovative approach can drastically reduce thecomplexity and cost of deploying a traditional WLAN network. Nortel Networks and NTU have already demonstrated advanced services over the Wireless Mesh Network solution, including video streaming, Wi-Fi voice over IP and
November 2004 ❖ IEEE Vehicular Technology Society Newsseamless hand-over while driving at speeds of 50km/h. The
Wireless Mesh Network solution incorporates 'auto discovery' and 'self healing' algorithms to simplify deployment byenabling installation in any location where power is available and reduces services outages by optimizing radio linkcommunications and minimizing interference. In addition,
the self-organizing nature of this architecture minimizes theneed for Radio Frequency engineering and commissioning,which can significantly increase WLAN coverage.

US Mobile Market

The Federal Communications Commission (FCC) has provided an additional twenty megahertz of spectrum that canbe used to offer a variety of broadband and advanced wireless services (AWS), potentially including 3G wireless services. The Commission allocated and paired five-megahertz
blocks of spectrum at 1915-1920 MHz with 1995-2000 MHz,and 2020-2025 MHz with 2175-2180 MHz for AWS use. The
Commission redesignated the 1915-1920 MHz band for AWS
from Unlicensed Personal Communications Services(UPCS) and pairs this five-megahertz block of spectrumwith the five-megahertz block at 1995-2000 MHz (which
was previously allocated for the Mobile Satellite Service(MSS)). An additional ten megahertz of spectrum at 20202025 MHz and 2175-2180 MHz – previously allocated for
MSS – is to be made available as paired five-megahertz
spectrum blocks. The Commission concluded that pairing
the bands in this manner promotes a more efficient use of
the spectrum and complements adjacent band operations.
The Commission also modified Part 15 of its rules withrespect to unlicensed PCS operations in the 1920-1930 MHz
band to provide additional flexibility for users of the band tooffer both voice and data services using a wider variety oftechnologies.
The FCC has adopted its Ninth Annual Report toCongress on the state of competition in the commercial
wireless (CMRS) industry. The Commission found that
97% of the total U.S. population lives in a county withaccess to 3 or more different operators offering mobile telephone service, up from 95% in the previous year, and up
from 88% in 2000, the first year for which these statistics
were kept. The Commission found somewhat larger
increases in the percentage of the U.S. population living ina county with access to 4 or more, 5 or more, 6 or more, and7 or more different mobile telephone operators in the past
year. The FCC noted that average monthly churn rates
remain at about 1.5 to 3.5% per month and that the adventof wireless local number portability in November 2003 haslowered consumer switching costs. In the 12 months ending December 2003, the US mobile telephony sector
increased subscribership from 141.8 million to 160.6 million, raising the nationwide penetration rate to approximately 54% of the population. Average minutes of use persubscriber per month increased to more than 500 minutesby the end of 2003 from 427 minutes in 2002 and 255 minutes in 2000.
The FCC has adopted a general prohibition on sending
commercial messages to any address referencing an
Internet domain associated with wireless subscriber messaging services. To assist the senders of such messages in
identifying those subscribers, the Commission required thatcommercial mobile radio service (CMRS) providers submit
those domain names to the Commission for inclusion in alist that will be made publicly available. No individual subscriber addresses will be collected or included on this list.
MeshNetworks has announced that it has been granted
November 2004 ❖ IEEE Vehicular Technology Society Newsa new experimental license from the FCC to deploy a number of fixed and mobile experimental mesh networks. This
experimental license allows the company to conduct nationwide trials of new products and technologies at 2.5 GHz andin the newly created 4.9 GHz public safety band. The FCC
decided to dedicate the 4.9 GHz band exclusively for use by
the public safety community. MeshNetworks solutions
leverage battlefield networking technology originally developed for the U.S. military under DARPA directed programs.
Specifically, the grant allows MeshNetworks to deploy atotal of 1000 nodes, with a maximum of 200 per demonstration network. These quantities will enable the company todeploy metro scale demonstration networks.
Cingular Wireless has been awarded a contract by the
National Communications System (NCS) to provide
Wireless Priority Service (WPS) to the country's authorized
emergency response personnel. Total network deployment
will be complete by the summer of 2005. WPS provides
authorized Federal, State, and local government leadersand critical private sector leaders and decision makers withpriority wireless service during times of emergency. In timesof congestion, authorized users are moved to the front of thequeue, greatly increasing their chances of call completion.
At the same time, WPS is designed to have a negligible
impact on everyday cellular users, providing priority service
to vital decision makers without restricting the public's ability to gain access to those same networks. WPS does notenable users to preempt existing calls or to monopolize cellular services.
Cingular Wireless, AT&T Wireless and Triton PCS havesigned a definitive agreement that - contingent on closing of
Cingular's acquisition of AT&T Wireless - would give
Cingular expanded wireless service in Virginia and Triton
PCS added coverage in North Carolina as well as entry into
Puerto Rico and the U.S. Virgin Islands. The companies
expect the Cingular/AT&T Wireless merger to close in 2004.
Leap Wireless has signed an agreement to acquire a wireless operating license in Fresno (California). The 30MHz
license covers approximately 950,000 potential customers.
MetroPCS has purchased a 20MHz C block license from US
Cellular in Daytona Beach. Centennial Communications
has announced the purchase of 10MHz of spectrum from
AT&T Wireless. The spectrum covers contiguous markets in
Michigan and Indiana.
Verizon Wireless, a CDMA operator, has launched a
Samsung handset (a790) that enables their subscribers toroam onto GSM networks overseas. The Samsung handset
incorporates GSM and CDMA technology using Qualcomm’s
MSM6300 chipset solution, designed to allow global roaming between GSM and CDMA2000 1X networks.
The city of Philadelphia has announced plans to launch acitywide wireless network. The intention is to mount up to
16 Wi-Fi routers per square mile on streetlights. Boston andMadison are said to be considering similar options.

Spectrum Licenses

Brazil has announced it has sold 2 out of 6 mobile phonelicenses, for less than 25% of the total in reserve prices forthe six licenses. Claro and Telemig Cellular acquired thelicenses. For the other 4 licenses there were no bidders.
Romania has launched the sale of four 3G licenses. The
government is expected to select the winners for the 15-year
licenses in the first half of November. The licenses are being
offered for about _35million each. Romania, with a population of 21.5million, has four mobile operators that offer service to about 8.3million users.

35

Canada has announced its decision to rescind the mobile
spectrum cap policy that limited the amount of radio spectrum that cellular operators could hold. The mobile spectrum cap policy was introduced in 1995 to encourage innovation and help the entrance of new operators. The Ministryof Industry will continue to manage the licensing of spectrum resources.
According to a new report from Analysys (‘Spectrum
Trading and Liberalisation’), the introduction of spectrum
trading and the liberalisation of the use of specific spectrum
bands will play a key part in creating a more dynamic, competitive and innovative wireless service market. The firm
said that growing numbers of countries have already adopted, or are in the direction to do so, regimes that will allow
operators to obtain tradable rights in radio spectrum in an
attempt to increase efficiency and innovation.

Industry Forecasts and Surveys.

According to Gartner, worldwide mobile phone sales surpassed 156.4 million units in the second quarter of 2004, a
35% increase from the second quarter of 2003. On a regional basis, the Western European market is being driven by
consumers who got their first mobile phones in 2000 and
2001, and now they're upgrading to smaller color screen
phones with built in cameras that have become available atmuch lower prices. Brazil continued to be the driving force
in Latin America, although Mexico also contributed strong
sales in the region. In North America, replacement sales
were high. More than 300 million mobile phones have beensold in the first half of 2004, and Gartner analysts have projected year-end sales to reach approximately 620 million
units. On the other hand, IDC said that worldwide mobile
phone shipments in the second quarter of 2004 increased
2.5% over the first quarter and rose 36.7% year-over-year to163.7million units. In the vendors ranking, Nokia is still
first (with a 27.7% market share), followed by Motorola(14.7%), Samsung (13.9%), Siemens (6.4%), Sony Ericsson(6.4%) and LG (6.1%). In a different report, IDC said thatthe worldwide handheld devices shipments increased 3.2%
sequentiall and dropped 2.2% year-over-year in 2Q04 to
2.2million units. On the other hand, Canalys reported thatthe mobile device market in EMEA experienced a 52%
increase in 2Q04 compared to the same period in 2003.
ABI Research has forecasted that during 2004 the worldwide base station new deployments will increase by morethan one third over 2003 but will decline, in 2005, byapproximately one fifth from 2004. According to InStat/MDR, 2004 worldwide cellular base station revenue
will be down 14.4% from 2003 due partly to price pressuresand an increase in spectrum efficiency. However, the firm
said that the actual number of base stations is forecasted toincrease slightly, from 329,483 in 2003 to 333,876 in 2004.
In-Stat/MDR also expects that by 2008, WCDMA will represent 23.1% of deployed base stations worldwide and GSM
61.5%. Dell’Oro has said that total mobility infrastructure
revenues, including sales of GSM/GPRS/EDEG, TDMA,
CDMA and WCDMA equipment has reached $9billion in thesecond quarter of 2004, which represents an increase of 37%
compared with the same period in 2003. GSM/GPRS/EDGE
network sales accounted for 60% of the net increase.
Although the market for WCDMA infrastructure equipment
fell 19% over the same period of time, the firm expects thismarket to grow in excess of 50% in 2004.
Strategy Analytics has estimated, in its Cellular Data
Forecast model (2004-2009), that global revenues frommobile data will grow from around $61billion this year to36

just over $189billion in 2009, with person-to-person messaging representing 48% of the total. A new study by the
ARC Group predicts that by 2009 wireless data access revenues, from cellular networks and hotspots, will have grown
to $130billion worldwide. The firm expects that 72% of theserevenues will come from wide-area networks. In terms of
Wi-Fi hotspots, the number will grow to 134,700 by 2006.
North America is expected to have more than 61million
hotspot users by 2009. A study from Mobinet has reported
that 41% of global wireless phone users expect to be regularor heavy users of data services by 2005. The more frequentreasons for justifying not using such services today were
cost (35%), security and privacy concerns (22%), and slow
network access (18%).
A study from the Yankee Group predicts that peer-to-peer(P2P) multimedia messaging service will generate more revenue than P2P short message service by 2008. Frost &Sullivan expects a significant drop in the contribution of
SMS toward mobile data revenues from 90% in 2003 to 40%
in 2008. The firm expects that MMS will achieve a 65% penetration rate in 2008, which will create 210million active
users and $10billion in revenue for mobile operators.
Meanwhile, MMS traffic in Telia’s mobile network in
Sweden increased sharply during July (most popular vacation month) with more than 1.6million MMS sent, which
represents twice the number sent in June. The Mobile Data
Association (MDA) has said that the volume of person-toperson text messages sent in August in the UK rose 29% on
the year to 2.2billion. The MDA said that 79 million texts
were sent on the 26th of August after UK exam results were
published.
A new report from Strategy Analytics predicts that overthe next 5 years, there will be an expected six-fold growth in
the mobile games market, with downloadable games generating 82% of this _6.65billion market. In terms of Java and
BREW capable handsets, the number will rise from 186million units this year to over 1billion in 2009. The firm also
expects the number of downloadable games’ users to growfrom 32million this year to 220million in 2009. In a different
report, In-Stat/MDR estimates that by 2009, mobile gaming
services in the US will generate $1.8billion annually, which
represents 4.4% of total wireless data revenues.
The Pierz Group estimates that the addition of mobile
numbers to the US directory assistance/enquiry database
could translate to a revenue of nearly $2billion by 2008.
According to the firm, 53% of all telephone subscribers are
unreachable through DA/DQ services, with 97% of mobile
phones unlisted.
In a new survey, conducted by Wavelink Corporation,
79% of the survey respondents said they plan to pilot or
implement an RFID solution. Of this number, 22% havealready implemented a pilot RFID program, while 42%
will implement it in the next 12 months. The remaining
21% of respondents plan to implement an RFID solution
within 12 to 24 months. The top reasons cited for implementing RFID included improving the ability to track
goods, meeting customer requirements and receiving
greater efficiencies in shipping and receiving. The survey
also revealed a critical need to address key concerns associated with RFID, including high cost, an early, untested
market and lack of sophisticated software to integrate
RFID with other business applications like supply chain
management and ERP systems.
According to a report from VDC, the US military is thelargest proponent and purchase of software-defined radio
equipment. The firm expect SDR shipment to the US miliNovember 2004 ❖ IEEE Vehicular Technology Society News

tary to reach more than $1.7billion in 2007, representing acompound annual growth rate of 48.4% between 2003 and2007. The Department of Defense’s JRTS program accounts
for most of the SDR purchase.
A new report from Parks Associates predicts that, by theend of 2009, there will be more than 7million subscribers
worldwide using broadband wireless services based on
802.16REVd technology. The firm also said that the market
is unlikely to see volume commercial deployment until 2006.
The CDMA Development Group (CDG) has reported that
the CDMA industry added nearly 10.5 million subscribers in
2Q 2004, reaching 212.5 million users worldwide, and in thefirst six months of 2004, the subscriber base grew by arecord 24 million users. From 2002 through the first half of2004, the CDMA subscriber base increased by an average of
30% per year versus 21% for the total wireless market.
3G Americas has reported that customers in the Western
Hemisphere are quickly adopting GSM wireless technology,
making it the number one choice of new cell phone customers. In Latin America, the total number of GSM customers reached 36 million, surpassing the number of CDMAcustomers by 1.6 million as of June 2004. Globally, GSM
accounted for 82% of new digital wireless customers representing 57.8 million of the 70.3 million net subscribers
added in the second quarter. In the U.S. and Canada alone,
GSM annual growth was nearly 85%, four times the growthrate of other mobile technologies.

Wireless LAN

Alcatel has deployed for ONO an end-to-end Wi-Fi solution
for the Royal Nautical Club at the Valencia seaport (Spain).
Valencia will be hosting the 32nd America's Cup in 2007.
This solution offers a fiber and radio supported broadband
connection, placing the Royal Nautical Club of Valencia inthe vanguard of telecommunication technologies. Alcatel's
Wi-Fi outdoor solution for the Valencia seaport provides
broadband connections to more than 300 users simultaneously and places particular emphasis on security issues andaccess management. In order to fit out Wi-Fi access point
systems, a mixed design with fiber-Ethernet converters has
been developed.
Siemens, working in collaboration with WLAN software
vendor Garderos and Cisco Systems, has built an extensive
network of WLANs for Greece’s Vodafone–Panafon, in which
WLAN services provide a seamless roaming experience
across five countries and which also offers centralized, cashless billing. Vodafone customers in Greece, France, Italy,
Switzerland and Portugal can now take advantage of fastInternet access at all hotspots in the network system andpay conveniently via their regular telephone bill. Siemens
integrated the WLAN solution into the infrastructure of the
Greek mobile network. In this context, Cisco delivered its
IP-based Service Selection Gateway (SSG), while Garderos
software was integrated into the "Siemens WirelessIntegration Platform" in order to provide the customers of
this Greek provider with extremely flexible billing options.
Ericsson has announced the supply of over 6,000-accesspoints to The Cloud. The access points will be integrated
into different public locations around UK. The Cloud operates a multi service-provider Wi-Fi platform, which allows
providers such as ISPs, mobile operators and cable companies to offer a fully branded WLAN experience to their customers. The Cloud offers national WLAN coverage withmore than 4,300 hotspot locations and is opening more than
100 new locations each week.
NTT DoCoMo has announced that it will extend its interNovember 2004 ❖ IEEE Vehicular Technology Society News

national roaming service to 33 countries for its public
WLAN service, under an agreement with iPass, a U.S.based provider of connectivity services. The 33 countries
span North and South America, Europe, Asia, Oceania, andAfrica. Users will be able to use WLAN services available atmore than 3,000 international high-profile hotels (24 countries) and passenger terminals at 82 international airports(17 countries).
According to Dell’Oro Group, enterprise LAN revenue
increased to $204million during the second quarter, with thegrowth primarily due to sales of access points with WLAN
switch/server appliances. In the later market, Symbol
Technologies appears as the leader increasing its market
share by 20 percentage points. The firm also predicts thatsales of WLAN products will grow 20% in 2004 to $2.1billion. Dell’Oro expects enterprise-class access point shipments to increase by 75% in 2004, growing at an averageannual rate of 47% through 2008. In a different study, IDC
has reported that the EMEA WLAN market declined by
10% in the second quarter of 2004 but is up 188% year overyear, reaching a total end-user revenue of $320million. The
firm has said that price erosion and lower shipments ofaccess points and add-on clients are the main cause for therevenue decline. A new study by the Radicati Group predicts
that by year-end 2004 there will be 39million WLAN consumer and enterprise users. The firm expects that, by 2008,
there will be 120million WLAN users and that the worldwide revenue for WLAN Infrastructure, Security andManagement will reach $8.6billion. In a corporate survey
conducted by the Group, 40% of the companies that have
deployed WLAN said that ease-of-use was the best productfeature against a 30% stating that it was its roaming capabilities. In-Stat/MDR expects WLAN equipment revenues in
China to increase at a near 33% CAGR from about $54million in 2004 to almost $160million by 2008. The researchfirm also said that foreign equipment providers have a combined 70% share of overall revenue.

Ultra Wideband

Pulse~LINK has conducted the first public demonstrationsof its RF ASIC capable of simultaneously transmitting UWB
communications wirelessly, over cable television networks
and electrical wiring, as well as narrowband communications such as WiFi and Bluetooth. The simultaneous transmission of each of these communications types from a common chipset is made possible by Pulse~LINK's latest digital-to-analog converter (DAC) 0.18 micron silicon
germanium test chip. With performance tested up to 20
Giga-samples per second, the DAC can perform direct digital synthesis of any UWB pulse shape or narrowband carrier between DC and 10Ghz of spectrum. Pulse~LINK demonstrated its DAC generating pulses shaped specifically for
UWB communications across in-home electrical wiring,
UWB communications on a 750 Mhz cable television network, wireless UWB communications covering multiple
modulation techniques, and narrowband carriers at 2.4Ghz
that is used for WiFi 802.11b/g and Bluetooth, as well as at
5.1 to 5.3 Ghz that is used for WiFi 802.11a. Pulse~LINK
has also conducted public demonstrations of multiple
streams of high definition television being delivered via
Pulse~LINK's UWB cable, power line, and wireless technologies. Pulse~LINK's UWB cable demonstration was conducted utilizing a miniature version of a metropolitan area
hybrid fiber coax infrastructure featuring multiple streams
of standard cable television feeds operating simultaneously
in the presence of UWB enabled HDTV content.

37

Freescale Semiconductor has partnered with several
companies in Taiwan for the development of UWB into consumer electronics. In particular, it is working with
Universal Scientific Industrial to develop a UWB-enabled1394 module intended for use in wireless LCD televisions
and home media services. With Gemtek, it is working todeliver a UWB-enabled mini-PCI module for video and data
streaming applications. GlobalSun Technology is also working with Freescale to create a mini-PCI module.
In-Stat/MDR has projected that UWB node/chipset shipments will experience an emerging market compound annual growth rate of over 400% from 2005 to 2008. According to
the firm, UWB-based products will only start to roll out in
2005, with a small level of shipments based on proprietarychipsets from Freescale and General Atomics. In-Stat/MDR
also claims that, as UWB rolls out, it faces no serious competing technologies, since alternatives only offer slower
ways of accomplishing data transfers, with speeds that are
1% to 10% of a 480Mbps UWB solution.

Forums and Industry Alliances

Fourteen service providers, infrastructure suppliers, andhandset manufacturers in the wireless industry have published a set of open specifications for extending mobile voice
and data services over Wireless LANs. With the UMA specifications, service providers can look to deploy interoperable
solutions that enable subscribers to roam and handoverseamlessly between cellular networks and public and private WLANs using dual-mode mobile handsets. More information about UMA technology, as well as access to the UMA
specifications, is available through the UMA technology
website (www.umatechnology.org).
Motorola, NEC, Nokia, Siemens and Sony Ericsson haveannounced their co-operation in the Mobile Broadcast
Services work, started under Open Mobile Alliance, OMA.
The charter of the work is to specify the enablers needed tobring broadcast services to mobile devices and to open up
the market for new exciting mobile services and terminals.
A likely spearhead service of mobile broadcast is mobile
phone TV. In general, mobile broadcast will enable cost efficient mobile mass delivery of any multimedia content.
A Fixed-Mobile Convergence Alliance (FMCA) has been
formed to accelerate the development of fixed-mobile convergence products and services. The founding members of
the alliance include Brasil Telecom, British Telecom, Korea
Telecom, NTT, Rogers Wireless and Swisscom.
The World Wide Web Consurtium (W3C) and the Open
Mobile Alliance (OMA) have announced a Memorandum ofUnderstanding (MoU) to collaborate on specifications formobile access to the web. OMA develops interoperable
mobile data service enablers. W3C develops recommendations including XHTML Basic, SMIL and mobile SVG.
The Mobile Marketing Association has announced theformation of an anti-spam committee. The committee will
research the merits of a national preference and privacy
database designed to ensure a spam-free mobile experience.
The system is expected to be open, flexible and optional. The
association has already released in 2003 a Code of Conduct.
Wireless, PMR and Public Safety.
MeshNetworks and Motorola have signed an agreement
enabling Motorola to distribute the MeshNetworks EnabledArchitecture (MEA) mobile ad hoc networking solution. The
MEA solution’s self-forming, self-healing mobile broadband
networking and precision position-location solutions will beoffered as part of Motorola’s advanced wireless broadband
data portfolio for enterprise, utility and public safety. By

38

leveraging MeshNetworks technologies, users equippedwith a mobile computer, a PDA, or other Motorola-powereddata device are able to join with other users to create an ad
hoc broadband network capable of operating under harshconditions, even in the absence of existing radio infrastructure. Every mesh-enabled radio serves as a router/repeaterfor every other radio - automatically extending the range
and robustness of the network. Broadband data, video andasset tracking are available on scene, even if a natural ormanmade disaster has destroyed the surrounding radio
network. MEA network products operate in the unlicensed
2.4 GHz band and leverage patented radio technology to
mitigate intentional and unintentional interference fromother devices within the band.
Motorola has launched its new Mobile AutomatedFingerprint Identification System (Mobile AFIS). The solution includes advanced tools previously available only inforensics laboratories and enables public safety officials to
rapidly establish the identity of an individual by providing
remote access to fingerprints, facial images and criminal
history records.
Nokia will be providing a TETRA system to The Societédes Autoroutes Paris-Rhin-Rhône, which operates motorways across central eastern France. The system features the
Nokia TETRA Neat architecture, tailored for a motorways
type of network. Nokia has also announced the availabilityof the THR880i hand portable radio, which incorporates a
GPS receiver and enables radio users to send their coordinates to a predefined address simply by pressing a button.
The device will be available in three frequency bands (380,
410 and 800MHz bands).
Alcatel will install a TETRA network for the Parisianpublic transport agency (RATP), one of the world's largest.
The network will cover Paris' extensive Metro, express line
and bus system. The TETRA network to be deployed by
Alcatel comprises six Nokia TETRA switches and around
500 TETRA base stations, as well as operator consoles
developed by Alcatel using Nokia's open interfaces, andAlcatel's mass transit-specific applications. The network
will enable mobile voice and data connectivity for over
10,000 personnel.
Belgocontrol, the Belgian air navigation service provider,
has selected Motorola to supply a state of the art TETRA
system. The Motorola Dimetra IP system will consist of
three sites covering Brussels National Airport. It will be
used by approximately 1,000 users for both voice and dataaiding communication between different organizations anddepartments in the airport. The US manufacturer has alsoannounced it will be providing a TETRA system to the
Aeronautical Radio of Thailand (AEROTHAI) for the New
Bangkok International Airport. The 800 MHz TETRA system comprises 3 base sites with a total of 28 base radios, andmore than 2300 portable and mobile radios to support thecommunications requirements of the new airport. Other
new networks to be provided by Motorola include theChengdu Emergency Response Centre and the first line of
Tianjin Metro. The network for the Chengdu Emergency
Response Centre, which includes 8 base stations and 10,000
subscriber units, will be integrated with the Emergency
Response Centre’s existing analog system.
NICE Systems and Motorola have announced the availability of a critical new solution for ASTRO 25 Trunked
Radio Systems. The logging solution provides digital voice
and data recording of transmissions enabling public safety
and governmental agencies to record and store the complete
history of an incident as it is happening. Through a collaboNovember 2004 ❖ IEEE Vehicular Technology Society News

rative effort, NICE has created a voice recording forMotorola’s ASTRO 25 Trunked Radio Systems that will
enable mission critical agencies to search for and replay
telephone calls and radio transmissions, including radio andtalkgroup identification and aliases.

Other News

Cosmote, a Greek mobile operator, has announced that its
Olympic Network performance resulted in a 100% successrate in the coverage of all Cosmote mobile traffic of the
Olympic Games, with more than 34.1 million minutes, averaging 2 million minutes a day from the 13th until the 29thof August. During the above mentioned period, more than
32 million calls were made inside and around the Olympic
Venues. It is worth mentioning that in the Athens Olympic
Complex itself, for which Cosmote increased network capacity by 15 times, the number of calls surpassed 5.7 million.
During the Olympic Games, the number of text messages(SMS) exchanged exceeded 100 million. Cosmote’s GPRS
network carried 27 million Kbytes of data volume. In total,
approximately 600 million calls were successfully made on
Cosmote's network during the Olympic Games. Vodafone
also announced that more than 115 million SMSs were sent,
during the event, through its network. The company's network handled with success more than 5.3 million GPRS sessions, presenting an increase of 250% compared to therespective period last year. Overall traffic in the GPRS network during the sports events exceeded 290 million bytes,
out of which 75 million bytes (or more than 25%) concerned
volumes of data coming from visitors using the 71 foreign
networks associated with Vodafone through relevant commercial agreements. During the event, Vodafone’s network
successfully carried off more than 35 million minutes ofvoice time.
Vodafone Spain, A. Menarini Diagnostics, Siemens
Mobile and Pulso ediciones have announced the launch of
the Medical Guard Diabetes(r) service. The Medical Guard
Diabetes(r) service uses mobile communications to giverusers control over their condition by sending the sugar levels to a database, completely automatically and safely. The
patient's sugar level meter is connected to a mobile handset
via a specially-designed electronic device (GMT). This service provides the user with his status and the exact time of
the measurement, avoiding possible errors or forgetfulness.
Motorola and Partners Telemedicine, a service ofHarvard Teaching Hospitals, have announced a collaboration to test MOTOHEALTH, a Motorola solution that uses
mobile phones to help healthcare providers monitor chronically ill patients as they go about their normal daily routines. MOTOHEALTH uses FDA-approved body sensors totransmit data about the patient’s condition to the healthcare provider via the patient’s Motorola mobile phone.
The ITU Asia-Pacific Telecommunication Indicators 2004
report, issued at ITU TELECOM ASIA 2004, found thatgrowth rates for fixed lines, mobile subscribers and Internet
users over the last few years have soared in a number ofcountries across the region. Mobile subscriber numbers rocketed by 31% per year between 2000-2003 to reach 560 million— overtaking North America as the world’s largest market.
Numbers of fixed lines in the region also grew by 14% in thesame period, surpassing the single digit growth rates seen in
most other regions. The number of Internet users in the
Asia-Pacific region also experienced rapid growth — 38%
year on year from 2000-2003. At the end of that period, thenumber of Internet users in the region amounted to 255 million, surpassing North America, which grew by 18% to reach
227 million users by yearend 2003. In comparison,
Europe/CIS grew by 20% from 2000-2003, reaching 191 million in 2003. New wireless technologies, which are currently
being developed, could further help to extend the reach of
ICTs into previously untapped rural or remote areas. At theend of 2003, total telephone penetration — fixed and mobile— in lower-income economies in the region was 22.6%, compared to 139.4% in the region’s upper-income economies.
Nokia has launched a new barring solution for the safe
and controlled usage of mobile content services as part of
the Nokia Intelligent Content Delivery (ICD) solution. The
barring solution is based on subscriber and mobile service
recognition. It allows mobile users to control access tomobile content services - for example, parents can preventchildren from accessing undesirable or unwanted services.
The barring solution maps subscriber and service profile
information to meet the growing demand for filtering out
inappropriate mobile content.
Belgium’s Proximus, the Government of Flanders and
ITIS Holding are planning to pilot a new traffic collection
technology for measuring real-time traffic flow based onanonymously sampling the positions of mobile phones inmoving vehicles. The trial will be conducted in the Antwerp
region.

Standards
Dennis Bodson, Senior Editor

IEEE-SA Standards Board approves P1616a

The IEEE SASB at their March 25, 2004 meeting approved
P1616a, Standard for Motor Vehicle Event Data Recorders(MVEDRs) - Amendment 1: Brake and Electronic Control
November 2004 ❖ IEEE Vehicular Technology Society News

Unit (ECU) Electronic Fault Code Data Elements. The
scope of this project is to develop an amendment for brakeand transmission electronic control units that requires
units to store a full history of electronic fault codes that are39

time stamped using a recognized clock synchronized withother on-board motor vehicle event data recording devices.
This project has particular emphasis on heavy vehicle
Brake and Electronic Control Unit (ECU) fault code data
elements. End users of this data include government, automotive industry, medical injury, legal profession, insurance
industry, crash reconstructionists and academia
researchers.

IEEE to Standardize Brake and Transmission
Input to Motor Vehicle Event Recorders

The IEEE has begun work to ensure that brake and transmission data is recorded uniformly in motor vehicle event
data recorders. The new project, IEEE P1616a™, "Standard
for Motor Vehicle Event Data Recorders (MVEDRs),
Amendment 1: Brake and Electronic Control Unit (ECU)
Electronic Fault Code Data Elements," will require units tostore a history of time-stamped fault codes synchronizedwith other on-board MVEDR devices.
The project responds to a safety recommendation madeto the IEEE by the National Transportation Safety Board
asking that data from brake and electronic control units forcars, trucks and other vehicles be included in the soon-to-becompleted IEEE P1616 MVEDR base standard. "This willbe the first independent communications protocol for brakeand transmission fault codes in highway vehicles," says Tom
Kowalick, Chair, IEEE P1616 Working Group and Professor
at Sandhills Community College in Pinehurst, N.C. "Ouroverall goal is to give all parties, from auto, truck, bus andother vehicle manufacturers to insurers, fleet owners, transit agencies and emergency first responders, ready access touniform data.""We will, in all likelihood, enhance IEEE P1616a so it
becomes a broad standard that involves other technologies
and end-user requirements beyond brakes and transmissions. We are thus seeking a wide spectrum of volunteers towork on IEEE P1616a. Everyone is welcome to contribute.
Upon its completion, this amendment will be incorporated
into the base MVEDR global standard."

Introducing “myBallot™” – The Better Way
to Ballot

Get ready for a new and improved balloting system in 2005!
Called "myBallot™," you will, for the first time, be able tocustomize your balloting experience all with a few clicks ofthe mouse! This means that:
If you are a Balloter:• and you want to join open balloting groups, you caneasily do so at your convenience by logging on to the
myBallot™ website; and,• if you are in a balloting group and wish to submit yourvote and/or submit comments while the ballot is still
open, you can do so as often as you like up to the closing date; and,• if, during a ballot recirculation, you want to review
responses from the ballot sponsor to your comments,
you can view those responses online.
If you are a Sponsor:• you can start your own invitation and ballot at yourconvenience, including choosing your own opening andclosing dates; and,• you will be able to see how many invitations are being
sent, and to whom; and,• you can delegate balloting work to a Ballot Designee
who can do everything from start the invitation toextending the ballot; and,40

• you can extend the ballot if the response rate has notbeen met or can choose to fail the ballot and start
anew; and,• you can gather RevCom documents pertaining to balloting directly from the system.
The new myBallot™ system represents a paradigm shift
in your balloting experience:• rather than waiting to be invited to join balloting
groups, you will be furnished with the opportunity tosign up yourself.
• rather than waiting for Balloting Center Staff yourchange your email, you will have a mechanism tochange it yourself.
• rather than waiting for ballot summaries, you can findresults of closed ballots at any time inside the
myBallot™ system.
Prepare now for the unique opportunity to direct, manage and control your own Standards Sponsor balloting experience through the introduction of myBallot™ – the betterway to ballot.
Get your IEEE Web Account now if you do not alreadyhave one – this will be your means of accessing the
myBallot™ system. And when you get your IEEE Web
Account, it's a good idea to update your contact information
with IEEE as necessary.

CDMA2000 1xEV-DO Revision

The CDMA Development Group (CDG)(www.cdg.org)
reported that CDMA2000® 1xEV-DO Revision A has been
approved by the 3GPP2 Technical Specification Group(TSG-C). Revision A is optimized for packet data service,and supports peak data rates of 3.1 Mbps on the forward
link and up to 1.8 Mbps on the reverse link. The high data
rates on the reverse link and low data latency will enable
operators to deliver rich multimedia services, such as video
telephony, and will enhance user experience.
“CDMA2000 technology continues to evolve to provide
unparalleled speed and efficiency,” said Perry LaForge,
executive director of the CDG. “With CDMA2000 1xEV-DO
Revision A, carriers will be able to further differentiate theirservices through a broad range of new, innovative wirelessdata offerings. Today’s announcement is yet another milestone for CDMA2000 and we are extremely pleased with theprogress 3GPP2 and the CDMA industry is making in delivering advanced technologies to meet the evolving needs ofwireless communications.”
CDMA2000 1xEV-DO Release A is an enhanced versionof CDMA2000 1xEV-DO Release 0, which delivers up to 2.4
Mbps data speeds and has been commercially deployedsince 2002. There are nine CDMA2000 1xEV-DO commercial networks in Asia, North America and Latin America
today, with four more scheduled to be deployed in 2004.
CDMA2000 1xEV-DO already delivers the highest data
rates in commercial networks (average data rates of 300-600kbps) and supports advanced data applications such as MP3transfers and video conferencing, TV broadcasts, video andaudio downloads.
Demand for advanced CDMA2000 1xEV-DO services is
growing rapidly; the number of users reached 4.38 million at
the end of 2003. In Korea, SK Telecom’s CDMA2000 1xEVDO base represents 25 percent of its CDMA2000 users after
less than two years of service. In January, Verizon Wirelessannounced the nationwide expansion of its CDMA2000
1xEV-DO network after the successful introduction of its
CDMA2000 1xEV-DO services in the San Diego andWashington, D.C. metropolitan areas in October last year.
November 2004 ❖ IEEE Vehicular Technology Society NewsIEEE-SA Standards Board Approves
P1512.4

The IEEE-SA Standards Board on 24 June 2004 approved
P1512.4, “Standard for Common Traffic IncidentManagement Message Sets for Use in Entities External
to Centers,” until 31 December 2008. A copy of the file canbe found at http://standards.ieee.org/board/nes/projects/1512-4.pdf.
The scope of the standard addresses Traffic IncidentManagement Message Sets which will be exchanged by andbetween mobile data terminals in response vehicles including mobile command posts and to their respective response
and/or dispatch centers such that the exchange of information will be standard and produce the needed response(s).
This standard will be limited to common message sets foruse by emergency management including transportation,
fire/rescue, enforcement, HazMat, etc.
The purpose of proposed project is to produce a set ofcommon message sets required for Traffic IncidentManagement exchanged between traffic incident responders. This standard will also address Traffic IncidentManagement Message sets that are exchanged between
responders and other field assets in response vehicles, tocenters, such that the exchange of information will be standard and produce the needed response(s).

IEEE Standard Amended to Enhance
Wireless Local Area Network Security

With the security of information and access an ongoing concern in the use of wireless local area networks (WLAN), theIEEE has approved a new amendment that greatly
enhances security in IEEE 802.11™ WLANs. The amendment, IEEE 802.11i™, will enable WLAN vendors to offer
highly secure wireless network interface cards, accesspoints and other products.
"IEEE 802.11i was developed by leading experts in network security to give end users and network administrators
a high level of assurance that the integrity of their networks
and data will not be compromised,” said Stuart J. Kerry,
Chair of the IEEE 802.11 standards committee.
IEEE 802.11i, “Wireless LAN Medium Access Control(MAC) and Physical Layer (PHY) Specifications: Medium
Access Control (MAC) Security Enhancement,” leverages
security technology that has emerged since the originalIEEE 802.11 standard was written in the late 1990s.
These developments include the Advanced Encryption
Standard (AES) and the IEEE 802.1X™ standard foraccess control.
“We wrote this amendment to support the wide range ofusers whose systems extend from small and simple units tolarge, complex networks,” said David Halasz, Chair of theIEEE 802.11i Task Group.
The amendment allows for security improvements inexisting wireless LAN products (through firmware
upgrades). Most current products can be upgraded to use
certain IEEE 802.11i features, such as Temporal Key
Integrity Protocol and IEEE 802.1x authentication. This
provides a considerable security improvement over the
Wired Equivalent Privacy feature in the original standard.
The amendment also contains options for backward compatibility with the original standard.
Even greater security can be gained in new products
having new hardware architecture. Products coming on
the market will be able to use the most advanced featuresof IEEE 802.11i, such as AES methods, key caching andpre-authentication for persistent authentication, which
November 2004 ❖ IEEE Vehicular Technology Society News

allows mobile stations to switch from one access point toanother without incurring the time overhead of a key
exchange each time.
“These and other enhancements in the amendment
should assure that IEEE 802.11i-based wireless LAN products can meet the demanding security goals of the growing
range of IEEE 802.11 WLAN applications expected in the
future,” Kerry said.

IEEE Approves Two Wireless LAN Projects
for Fast Roaming and Mesh Standards

The IEEE has approved the start of work on two projects
for fast roaming and mesh applications in wireless local
area networks (WLAN). The fast roaming project, IEEE
P802.11r™, will make it easier to use wireless voice-over-IP(VOIP) and other real-time interactive applications. The
mesh project, IEEE P802.11s™, will extend WLAN range byallowing data to pass through wireless nodes.
The Fast Roaming Task Group will standardize MAC
layer enhancements that minimize non-connectivity time
between a roaming WLAN unit and the wired access points
within a local area network. The standard will seek to foster
the use of mobile, wireless VOIP phones and other time-sensitive WLAN applications by eliminating perceptible disconnections as 802.11™-based handsets transition from one
access point to another during a handoff within an administrative domain of a local area network such as in a hospital,
an office environment, or a college campus.
Task Group s will create a mesh service standard so wireless access nodes spread over a large area can connect to amain node. This arrangement will extend coverage beyond
the typical WLAN connectivity limit of 300 ft. from anaccess point and make it quicker and easier to install WLAN
service without hard-wired connections. In a mesh, a single
access point can serve a large facility or broad sensor array.
Mesh networks can also allow the military to place repeater
nodes on mobile units that link to a central point or let afireman become a node in a communications network in an
emergency.
“The IEEE 802.11 Working Group is committed to creating standards for all aspects of wireless LAN operationworldwide,” said Stuart J. Kerry, Chairman of the IEEE
P802.11 standards committee. “Task Groups r and s reflect
this commitment. The standards they will develop should
help open a variety of new WLAN applications and continue to promote the rapid growth of IEEE 802.11-based wireless systems.”
New IEEE 802.11 study groups are also being formed for
wireless interworking with external networks and wirelessnetwork management. These will join the newly createdWireless Performance Prediction Study Group.
“I am pleased to see the continued strong industry support for the development of new projects within the Local
and Metropolitan Area Networks Standards Committee(LMSC). This new work is an excellent indicator of the vitality of the data communications industry and the importantrole the IEEE 802 LMSC plays in it,” said Paul Nikolich,
Chairman of the IEEE P802 LMSC.

IEEE Publishes Guide to its Traffic Incident
Communication Standards
Now that many states and localities have begun to
implement the IEEE 1512® family of transportation
emergency communication standards, the IEEE has
issued a guide for decision makers and managers at public safety centers and transportation centers that41

reviews the four standards in the series and how to put
them into effect.
IEEE 1512 standards foster efficient communication intraffic incidents. They create common message sets so allparties involved, from a 911 system to the police to a public
works department, can share information more easily inmanaging traffic incidents. The goal is to control resources
so as to reduce congestion, secondary collisions, and thetime it takes to clear an incident, as well as to improve interagency coordination and safety for travelers and emergency
personnel.
The “Guide to the IEEE 1512® Family of Standards” covers such topics as the need for the standards, issues related
to information sharing, table top exercises, and how toincorporate the standards into existing communication systems. It also includes implementation guidelines and casestudies on the equipment, software and policy changes
agencies have made to enhance interaction among 1512
standard users.
IEEE 1512 standards include a base standard and four
companion volumes:• The base standard, IEEE 1512™-2000, addresses message sets for traffic management, public safety andhazardous materials incident response in general.
• IEEE 1512.1™-2003 provides traffic management
message sets for transportation and public safety
agencies in transportation incident management.
• IEEE P1512.2™ provides message sets for interagency
coordination, dispatching and asset management fortransportation and public safety agencies.
• IEEE 1512.3™-2002 provides message sets for the
management of hazardous materials in transportation
incidents.
The “Guide to the IEEE 1512 Family of Standards” ispublicly available at: http://grouper.ieee.org/groups/
scc32/imwg/guide.pdf. To obtain copies of the IEEE 1512
standards, got to: http://shop.ieee.org/store.
IEEE 1512 standards are sponsored by the IEEE
Vehicular Technology Society.

Changes to the Bylaws

least 50 members of the Society. An affirmative vote of atleast two-thirds of the elected members of the Board ofGovernors will be is required to elect an Honorary
Member.

The Board of Governors have approved the followingchanges to the By-laws. They consist mainly of minor clarifications of the text, but the main substantive changes are:• Honorary membership can now be conferred on anyone, rather than only on existing VTS members.
• Ballots not longer explicitly have to be mailed, but canuse whatever procedure IEEE recommend. In the future
this could allow for electronic voting, for example.
• The Propagation Committee becomes a standing committee.
• The Electric Vehicles Committee is renamed the
Vehicle Power and Propulsion Committee.
• The Meetings Committee is renamed the Conference
Committee• The Publications Committee takes on responsibility for
the web site.
The detailed changes are below, with additions and deletions as marked.

II Membership
Section 2.0.
Honorary Membership in the Society may be awarded to amember by the Board of Governors.
The Board of Governors may award honorary Membershipin the Society to an individual.
Section 2.1. Election
Nomination for Honorary Member may be made by theSociety Awards Committee or by a petition signed by at

42

References

1. IEEE Press Release, May 9, 2004
2. IEEE Press Release, July 29, 2004
3. Press Release, Costa Mesa, CA, April 12, 2004
4. IEEE Press Release, July 22, 2004
5. IEEE Press Release, July 6, 2004

Section 2.2. Eligibility
Honorary Membership may be granted an outstanding
member who meets all of the following minimum
requirements:
(a)
(b)
(c)

He/She shall have made significant technical contributions to the field of interest of the Society.
He/She shall have performed outstanding service tothe profession and to the IEEE.
He/She shall have been a member of the Society for atleast 5 years.

V Nominations and Elections

Section 3.0. The Nominating Committee shall submit its
slate of nominees to the Board of Governors in time to complete the election prior to the final Board meeting for theyear. Upon acceptance by the Board of Governors, theSecretary shall forward the approved slate of nominees toIEEE Headquarters for submission to be mailed to themembership in accordance with using standard IEEE balloting procedures.
Section 4.0. The newly elected Governors shall be invited to attend the final meeting of the year of the Board
but will not have the power to vote until their terms
commence.

November 2004 ❖ IEEE Vehicular Technology Society News

Section 6.0. The election of the officers of the Board ofGovernors for the following calendar year shall take placeat the final meeting of the year of the Board of Governors.
The election shall be the last order of business prior toadjournment. The Board of Governors shall elect a
President, an Executive Vice President, a Vice President
Mobile Radio, a Vice President Motor Vehicles, a Vice
President Land Transportation, and a Treasurer. If there
are more than 2 candidates for an office and no one
receives a majority of the votes cast, a runoff shall be held
between the 2 receiving the greatest number of votes. The
Secretary shall be appointed by and serves at the pleasureof the incoming President. The Secretary need not be anelected member of the Board He/She does not have to be a
Governor, but must be a member of the Society. The first
duty of the Secretary shall be to notify the IEEE Technical
Activities Secretariat of the names of the elected officers.

VII Committees and Liaison
Representatives

Section 1.0. Committees are established to facilitate thecarrying out of the responsibilities of the Society in a particular area of endeavor. In some cases the responsibility iseffected by a Liaison Representative(s) to an other entity.
Committees are of two types: Standing and Ad Hoc.
Standing Committees cover areas which that are permanent and continuous in nature. Ad Hoc Committees are set
up for a specific purpose which that is temporary or noncontinuous nature. Committees may, at the discretion of
their Chairman or the Board of Governors, establish subcommittees. The committee chairman or liaison representative, unless otherwise specified by the Bylaws, shall be
appointed by the Society President with approval by the
Board of Governors. These individuals shall report on theiractivities to the Board on a regular basis.

VIII Standing Committees
Section 2.0. Technical Committees

At the beginning of the old clause Section 2.1, the text
Section 2.1. A technical committee is deleted, and theremaining text added to clause Section 2.0, so it now reads:
Section 2.0. Technical Committees may be established by
the Board of Governors to cover a special portion of the
field of interest of the Society. This special Committee shallprovide a source of technical and professional advice andassistance on the particular field of interest of the technical committee. In certain cases where a technical committee such as a technical standards committee is providing aservice to or on behalf of IEEE as well as the Society, thecoordination with the IEEE shall be effected to insure compliance with Institute requirements. If a technical committee covers a complete Field of Interest of the Society,e..g., Land Transportation, it may, at the discretion of themembers concerned and approval by the Board ofGovernors, be designated as a Division of the Society, andfunction as a subentity of the Society.
Section 2.12. Standards Committee
This Committee shall review the state-of-art and recommend the preparation of standards to the Board ofGovernors of the Vehicular Technology Society. Advanceapproval by the Institute Standards Committee shall be

November 2004 ❖ IEEE Vehicular Technology Society Newsobtained prior to preparation. The standards may establish specific performance criteria, measurement techniques, definition of terms and practices and guides for
specific applications. The substructure of the committee,
shall be the responsibility of the chairman, subject toapproval of the Board of Governors. The InstituteStandards Committee may also request the SocietyStandards Committee to prepare standards in the field ofvehicular technology.
Section 2.23. Motor Vehicle Committee.
This committee shall cover those areas of vehicular electronics and electrical engineering ordinarily identified
with the automotive industry.
Section 2.34 Land Transportation Committee.
This committee shall cover the technology relating to electrical and/or electronic aspects of ground transportation.
Section 2.45. Vehicular Power and Propulsion Committee
Electric Vehicle Committee. This committee shall cover thetechnology relating to the electrical and/or electronic
aspects of electrically propelled road vehicles.
Section 2.5 Propagation Committee.
The scope of this committee encompasses radiowave propagation issues. The committee shall provide publications
and services to the membership and to the Board as
requested by the Board.
Section 3.0 Administrative Committees. Administrative
Committees may be established by the Board of Governors tocover a particular area of Society operations. In certain cases
where an Administrative Committee such as the
Publications Committee or the Membership Committee isproviding a service to or on behalf of IEEE as well as theSociety, the coordination with the proper IEEE entity shallbe effected to insure compliance with Institute requirements.
Section 3.1 Publications Committee The Publications
Committee: (a) Recommends publication policy of theSociety. (b) Implements the Publications Policy establishedby the Board of Governors. (c) Publishes a Society
Transaction. (d) Publishes a Society Newsletter. (e) Assistsin the publication of any special Society publications
approved by the Board of Governors. (f) Recommends editors for the Society publication to the Board of Governors,(g) Recommends a Webmaster and maintains the Society’s
electronic publications including a website.
Section 3.2. Conference Meetings Committee. This
Committee will einsure Society participation in thearrangement for Annual Conferences Meetings of theSociety and in such other Conferences meetings of otherorganizations requested by the Board of Governors.
Section 3.7. Constitution and Bylaws Committee.
It shall be the function of the Constitution and Bylaws
Committee to maintain an up-to-date record of thisConstitution and Bylaws of this Society, and to insure
ensure on a continuing basis that the Society’s
Constitution and Bylaws are in accord with IEEE requirements. It shall be the responsibility of this committee toadvise the Board of Governors of any need or desire forchange in the Society’s Constitution and Bylaws and to43

prepare such changes as are appropriate when directed to
do so by the President or the Board of Governors. The
chairman of this committee shall also serve as theParliamentarian for the Board of Governors.
Section 3.9. Fellowship and Scholarship Committee(c) The current awards are Dan Noble Fellowship (jointlywith Motorola, Inc.), and the Transportation Electronics
Fellowship.
Section 3.12. Executive Committee. This Committee advises the Society president in the performance of his/herduties. It cannot take any action which that will restrict
the Board of Governors. Theis membership of thisCommittee shall consist of all the officers, the two mostrecent Past Presidents the Past President, Senior Past
President, and any other person the President may
require. The President shall chair the committee.

IX Ad Hoc Committees

Section 1.0. Ad Hoc committees may be established by the
President or the Board of Governors. If empowered by the
President, the committee cannot continue beyond the termof office of the appointing President. If empowered by the
Board of Governors, the life of the committee will be 1 year,
unless otherwise indicated declared by the Board ofGovernors. The life of a committee may be extended by the
Board.
Adopted and Approved March 6, 1953
Amended and Approved June 13, 1957
Amended and Approved April 20, 1959
Amended and Approved March 31, 1961
Amended and Approved October 15, 1969
Amended and Approved February 15, 1979
Amended and Approved January 23, 1993
Amended and Approved May 8, 2001
Amended and Approved May 18, 2004

2005 IEEE Vehicle Power and Propulsion (VPP) Conference
7-9 September 2005

Illinois Institute of Technology, Chicago, Illinois, USA

The 2005 IEEE Vehicle Power and Propulsion (VPP)
Conference is co-located with the 2005 SAE (Society ofAutomotive Engineers) International Future Transportation
Technology (FTT) Conference on the campus of Illinois
Institute of Technology (IIT) in Chicago, Illinois, USA.
Registrants for either conference will be able to attend thetechnical sessions of both. VPP conference will conduct sessions in different technical tracks and paper offers are being
invited on the following or related topics.
• VPP Track 1: Vehicular Electric Power Systems and Loads• VPP Track 2: Vehicular Power Electronics and Motor Drives• VPP Track 3: Advanced Vehicles• VPP Track 4: Energy Storage Components/Systems• VPP Track 5: Modeling, Analysis, Dynamics, and Control
Papers should make a timely contribution to state-of-theart technology, be of high technical and editorial quality, andbe devoid of commercialism. Prospective authors of papers
are asked to submit their paper proposals through the conference Web site by April 15, 2005. Each paper proposal must
include: an abstract of 50-100 words and a digest of 3-5 pages(including figures and tables) stating the objective of thepaper, outlining the problem requiring solution or the
method of approach to research, being explicit with respect
to the type of data to be included in the full paper, and summarizing the conclusions being made.
VPP/FTT General Chair: Prof. Ali Emadi
Illinois Institute of Technology, emadi@iit.edu
VPP Program Chair: Prof. John Shen
Uni. of Central Florida, johnshen@mail.ucf.edu
FTT Program Chair: Prof. Mehrdad Ehsani
Texas A&M Uni., ehsani@ee.tamu.edu

Conference of Interest

The following table shows VT-06 sponsored and co-sponsored conferences as well as related conferences not sponsored by theSociety. While every attempt was made to ensure accuracy, you should contact the respective conference committee to confirm date and location.
DATE

CONFERENCELOCATION

WEB PAGE

13-17 March 2005

WCNC 2005

New Orleans, LA

http://www.comsoc.org/confs/wcnc/2005/index.htm

16-18 March 2005

2005 Joint Rail Conference

Pueblo, CO

http://www.asmeconferences.org/jrc05/

11-15 April 2005

European Wireless 2005

Nicosia, Cyprus

http://www.vde.com/ew05

16-20 May 2005

ICC 2005

Seoul, Korea

http://www.icc05.org

29 May – 1 June 2005

VTC 2005-Spring

Stockholm, Sweden

http://www.vtc2005spring.org

19-22 June 2005

IST Mobile & Wireless Summit

Dresden, Germany

http://www.mobilesummit2005.org

926-29 September 2005

VTC 2005-Fall

Dallas, TX

http://www.vtc2005fall.org

9

Q2 2006

VTC-2006 Spring

Melbourne, Australia

mailto:fzheng@ieee.org

Conferences marked ‘9‘ have open calls for papers as of 1 December 2004. This list is based upon theconference calendar at our web site, which is updated more frequently than this list can be. To access it go
to the following URL: http://www.vtsociety.org/, then click on “Conference List” in the left frame.
Corrections and additions to this list are most welcome, and should be sent to Tom Rubinstein att.rubinstein@ieee.org.
√
Conferences marked ‘ ’ have open calls for papers as of 1 Decemeber 2004. This list is based upon the conference calendar
at our web site, which is updated more frequently than this list can be. To access it go to the following URL: http://www.vtsociety.org/, then click on “Conference List” in the left frame. Corrections and additions to this list are most welcome, andshould be sent to Tom Rubinstein at t.rubinstein@ieee.org.