No. 292 (October 2002)

New book reviews will appear here shortly

UMTS and related communication technologies

Over the past couple of years, we have received a number of books on UMTS and related communications technologies. Three of these books, from John Wiley & Sons, are reviewed here (with apologies to the publisher for the long delays!).

Introduction

Broadcasters are looking with interest at the progress of telecommunication technologies such as fixed, wireless and mobile systems. The EBU Broadcast Management Committee (BMC) recently established a new Project Group B/SYN (Synergies between broadcast and telecommunication networks, systems and services) to study possible scenarios for synergies and convergence. It is therefore very interesting for broadcasters to monitor what is going on in the area of two-way communications and the Internet.

There is a wealth of technical literature on different aspects of the Third Generation of Mobile Communications (3G) and John Wiley & Sons is far from being the only publisher to release massive quantities of books about this new technology. 3G was conceived in the late 1980s, born in the late 1990s and may be commercially introduced – in at least one country – in 2003 (i.e. about 15 years after its conception). The history of 3G is thus not too dissimilar to the introduction of digital broadcasting technologies: both have experienced some teething problems with the implementation of services in horizontal markets. And both systems have been the subject of extensive international research and standardization processes, with many groups, agencies, manufacturers and forums being closely involved. Even today, 3G is still being developed by a number of international organizations such as 3GPP (3rd Generation Partnership Project), 3GPP2 (the American equivalent of 3GPP, promoting cdma2000), 3GIP (a private pressure group to promote UMTS with IP multimedia), OHG (Operators' Harmonization Group), MWIF (Mobile Wireless Internet Forum) in addition to the well-known ITU, ETSI and IETF organizations.

Two "flavours" of 3G will be implemented in practice: UMTS (Universal Mobile Telecommunications System) has been promoted in Europe and Japan, and cdma2000 has been adopted by North America.

Why is UMTS needed? 1G (the first generation mobile system) was an analogue system offering only voice services. Each country used a different standard, so there were no roaming possibilities. 2G (Global System for Mobile Communication, GSM) introduced digital voice and messaging services, so it is more spectrum-efficient than 1G. It has become a de facto world standard; it allows for roaming in more than 150 countries worldwide. 3G will offer "true" broadband data access to video-on-demand, video communications, interactive games, etc.

Telecom and other operators hope (optimistically) that there will be a huge demand for 3G services – by the corporate and consumer markets – and many have paid huge amounts of money for the licences. However, the introduction of UMTS is being delayed, in part because the success of i-mode, GSM (with or without WAP) and packet-mode data GPRS (which is considered as 2.5G) have been well above expectations. These systems have provided important lessons as to which services may be of interest to the general public and how it is possible to make money out of them. Many believe that GPRS might be a viable intermediate stage towards the future UMTS system but, if commercially successful, the introduction of UMTS may be even further delayed.

Book 1:
GSM, cdmaOne and 3G Systems

This book is a comprehensive functional, technical and operational analysis of both the European GSM and American IS-95 (in 1997, renamed cdmaOne and, since 2000, referred to as cdma2000) systems. The third part, the most interesting one, covers the evolution of both these 2G systems towards a possible harmonized 3G system. Whereas GSM uses a combination of FDMA (frequency-division multiplex access) and TDMA (time-division multiplex access), IS-95 used CDMA (code-division multiplex access). In spite of the fact that CDMA entered the cellular world with a host of technical problems, its proponents won the technical arguments because of its very high spectral efficiency. Consequently, CDMA was proposed as the basis for 3G developments.

As mentioned above, the evolution from GSM to UMTS will not be direct. The GSM data rate was initially 9.6 kbit/s. This was based on a single timeslot-per-TDMA-frame. It has since been increased to 14.4 kbit/s by reducing the power of the channel coding, by means of code symbol puncturing. GSM can be refined even further by allowing the user to access more than one timeslot-per-TDMA-frame at a time. Two new systems allow that – High-Speed Circuit-Switched Data (HSCSD) and the General Packet Radio Service (GPRS). The latter one is more efficient because it uses additional timeslot channels only when a transfer of information (packets) is required. Another approach to increasing the user data capacity is to use a higher-level modulation scheme. At present GSM uses Gaussian Minimum Shift Keying (GMSK). The future system, termed EDGE (Enhanced Data Rates for GSM Evolution), would use GMSK in poor-quality propagation channels and higher-level modulations such as differential QPSK or coherent QPSK or, indeed, coherent 8-PSK, offering a maximum user rate of 43.2 kbit/s.

The book lists the main differences between UMTS and the legacy systems, in terms of transmitted spectrum and the main system characteristics such as the various channels: the common pilot channel, the common control physical channel, the page indication channel, the synchronization channel, the acquisition indication channel, and the transport channel. The book describes in quite detail the cell search procedures, the access procedure, the power control and the handover.

A technically-minded broadcaster will enjoy reading this book; there are plenty of mathematics and formulae to digest, and the understanding of how UMTS really works is not the easiest thing in the world.

GSM, cdmaOne and 3G Systems
Raymond Steele, Chin-Chun Lee and Peter Gould
Hardbound volume of 512 pages
Ref: ISBN 0-471-49185-3. Price £65.00.
John Wiley & Sons, UK.
http://www.wileyeurope.com/cda/product/0,,0471491853,00.html

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Book 2:
The UMTS Network and Radio Access Technology – Air Interface Techniques and Future Mobile systems

This book focuses entirely on UMTS and is probably a book variant of the full ETSI specification, which probably exceeds 4000 pages! The author was one of the principal contributors to, and evaluators of, the UMTS research and development programme.

The book provides a very high degree of detail and thus represents a useful vademecum for communication experts. Broadcasters will probably most appreciate Section 6 "Service components in UMTS". This section covers Quality of Service (QoS), multimedia transmission and the various traffic classes (e.g. conversational, streaming, interactive, etc). It also covers the cost predictions for UMTS services and the different types of subscription services.

It is interesting to note that the author sees the future of UMTS as an IP-enabled service. The wide-spread usage of the Internet, along with IP's ability to communicate between different networks, has made IP a convergence layer to evolve from a simple data platform to a universal platform for all multimedia services. By replacing the circuit-switch services, IP may represent a common interface between fixed and mobile systems. In addition, IP may enable a whole range of new wireless applications to be developed. It may even provide a synergy between telecom and broadcast networks, systems and services in the future, thus allowing the use of IP-enabled terminal devices (which could become available to the consumer on a massive scale).

The UMTS Network and Radio Access Technology - Air Interface Techniques and Future Mobile systems
Jonathan P. Castro
Hardbound volume of 354 pages
Ref: ISBN 0-471-81375-3. Price £55.00.
John Wiley & Sons, UK.
http://www.wileyeurope.com/cda/product/0,,0471813753,00.html

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Book 3:
CDMA: Access and Switching For Terrestrial and Satellite Networks

Code Division Multiple Access (CDMA) has been used in military applications for a very long time. As the complexity of algorithms is no longer a limiting factor, CDMA is increasingly used in advanced non-military communication networks, such as UMTS. CDMA can be considered as a generalised method for both the user access to services and the switching (routing) of communication services. CDMA can be seen as an all-embracing, unified approach for multiple access and switching in communications.

This book is written for university students and academia. It has little value for practising broadcasters. Nevertheless, it may be a useful companion for broadcast developers and researchers who are developing new broadcast transmission systems based on CDMA, such as "Broadcast UMTS" or "CDMA DVB".

It should be pointed out that CDMA was initially a candidate (among many others) for a modulation/coding system to be used for the digital audio broadcasting system (today known as the Eureka-147 system). However, it was not retained on the grounds that the system requires too wide a spectrum. This decision was taken some 17 years ago! In retrospective, the decision taken at that time to use OFDM/differential QPSK was not inappropriate, but had the development of the DAB system started from scratch today, CDMA would almost certainly have been considered as a first candidate.

The main value of the book is its attempt to describe how conventional CDMA technology has evolved towards an approach that allows for the unifying of different access methods. This generalised approach, G-CDMA, represents a super-set of multiple accesses, created from the different encoding sequences using spread-spectrum techniques.

CDMA: Access and Switching For Terrestrial and Satellite Networks
Diakoumis Gerakoulis and Evaggelos Geraniotis
Hardbound volume of 270 pages
Ref: ISBN 0-471-49184-5. Price £65.00.
John Wiley & Sons, UK.
http://www.wileyeurope.com/cda/product/0,,0471491845,00.html

Franc Kozamernik

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NHK Broadcasting Studies, No 1, 2002

NHK, the Japan Broadcasting Corporation, launched a new publication series in Summer 2002 – the NHK Broadcasting Studies. These will focus on social science aspects of the media rather than technical aspects, but it does engineers no harm at all to take an interest in such matters also. The intention is that this volume will be published annually, and will include a series of papers by largely Japanese authors, but also the occasional authors from outside Japan.

The first edition includes a paper on the future of public service broadcasting, written by Professor Vincent Porter from the University of Westminster in the UK. Prof. Porter is as coherent and convincing as usual, and considers many of the dilemmas which have already been discussed in the EBU Digital Strategy Group – about the role and nature of public service broadcasting in the digital environment.

The first edition also includes a paper on "Will the Internet take the place of Television?". This paper gives the results of a survey carried out in 2001, with hundreds of respondents in Japan, about their habits and changes to lifestyles essentially caused by the Internet and mobile phones. The paper doesn't really answer its own question, but there are nevertheless lots of fascinating result to be found. For example, although the larger group of respondents claimed that the use of the Internet has not affected their behaviour much, a sizeable proportion reported a decrease in letter writing, hours of sleep, telephone calls, TV watching, and magazine and newspaper reading – all due to time spent on the Internet. Surprisingly, it was found that going out and meeting people has risen slightly since the advent of the Internet. Maybe the hours you spend on the Internet makes you desperate to get out of the house!

The publication has other papers on television as a diversion device, and on what it means to be an Olympic host broadcaster. All in all, an interesting read with impeccable translations into English. Let us hope that NHK continues with the important and valuable series now started.

NHK Broadcasting Studies 2002, No. 1
Bound volume of 154 pages
Ref: ISBN 4-9901246-2-6. Price: Free of Charge.
NHK Broadcasting Culture Research Institute.
E-mail: nhkstudies@culture.nhk.or.jp

David Wood

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