November 2001
Edited by Andrzej Jajszczyk
Wireless Communication Technologies: New Multimedia Systems
Norihiko Morinaga, Ryuji Kohno, and Seiichi Sampei (Editors), Kluwer Academic Publishers, 2000, ISBN 0-7923-7900-4, hardcover, 321 pages
Reviewer: Asrar U. H. Sheikh
This book is the latest in the series of books based on a collection of topics of significance discussed at Personal, Indoor and Mobile Radio Communications (PIMRC) symposia since 1997. This book is divided into two parts. Part I covers new technical trends in wireless multimedia communications, and Part II deals with trends in wireless multimedia communication systems. Part I comprises a selection of seven key technologies that are considered the driving forces behind the new emerging multimedia communications systems. Each of the selected technology is described in a standalone chapter, which is written by one or more experts in that technological area. The technologies chosen for Part I are wireless channel modeling, space-time coding, coding for wireless, OFDM, multiuser receiver, software radio, and spatial and temporal communication theory.
In Chapter 1, the authors develop a new model for a wideband mobile radio channel. The emphasis is placed on the spatial and directional aspects of radio propagation. This selection is primarily dictated by the capacity enhancing technique called space division multiplexing. The authors of this chapter draw a duality between spatial and frequency selectivity. The concept of wavenumber introduced in this chapter relates the wavenumber with the well understood angle spectra. The concept leads to multipath shape factors, which describes the multipath angle of arrival characteristics. The chapter concludes with presentations of applications like measurement of angular spread, level crossing rates, and envelope decorrelation between signals on different antenna elements.
Chapter 2 is on space-time coding and signal processing for high-data-rate wireless communications. This chapter is nearly identical to articles published in IEEE Communications Magazine and Wireless Communications and Mobile Computing. The chapter underlines the concept of space-time coding and defines space-time block codes. An example of the properties of space-time coding for interference suppression is considered. The chapter considers applications of space-time coding to narrowband and wideband communications. In particular, the usefulness of space-time coding is demonstrated by considering capacity of multi-user communications.
In Chapter 3, the authors concentrate on coding for the wireless channel. The chapter describes the development of new criteria for code design for frequency flat, slow fading channel. The proposed new criteria are markedly different from the well-known Euclidian distance criterion used for AWGN channels. The developed criterion uses minimum Hamming distance, which provides a code gain through the so-called code diversity.
Chapter 4 presents OFDM as the most elegant solution for wireless digital transmission. The chapter goes into considerable detail on principle and design of OFDM system. Synchronization is presented as a significant problem and pilot assisted synchronization approach is suggested. The proposed method estimates the frequency offset and then compensates for the error. The chapter also discusses the blind synchronization approach, which jointly estimates the frequency offset, symbol timing, and symbol period.
Chapter 5 is an overview on linear multi-user equalizers for DS-CDMA. The chapter starts with presentation of the idea and basic principles of multi-user receivers for CDMA. Linear multi-user receiver formulation and combination of MAI suppression with multipath and antenna combining are the main contributions of this chapter. Alternative approaches for use of equalizers are also presented. These approaches include combining before equalization or equalization before combining. These systems have been analyzed for bit error probability. Finally, chip equalization as an alternative is introduced. The chapter concludes with a few examples.
In Chapter 6, software-defined radio technologies are discussed. The emphasis is on the structure of software-defined radio and how it differs from conventional radio. A comparison between FPGA and DSP-based architectures is discussed.
The final chapter of Part I is on spatial and temporal communication theory, which is based on adaptive antenna theory. In this chapter, after a brief introduction to antenna array, spatial and temporal channel model is introduced. The channel model thus developed is used to define spatial and temporal Nyquist criterion. Spatial and time equalization is then introduced. Several adaptive algorithms including LMS, RLS, CMA, and Applebaum are introduced, and their performance for beam tracking is evaluated. The techniques thus developed are extended to spatial and temporal joint equalizers and S&T joint multi-user transmitter and receiver system for CDMA.
Part II of the book is confined to trends in new wireless multimedia communication systems. It covers five topics: intelligent transport systems, wireless data communication systems, wireless Internet, digital TV broadcasting, and IMT-2000. These systems are now in various stages of standardization.
Chapter 8 introduces intelligent transport systems. In this respect, work by Communications Research Laboratory (CRL) of Japan is defined. After describing the experimental facilities for intervehicle communications, the chapter deals with an experimental system that transmits at 1 Mb/s. The analysis presented is based on a two-ray model. A section is devoted to the description of the configuration of a proposed system and experimental results. Development of a prototype system is also described. Development of a software radio prototype and its evaluation results are also given.
In Chapter 9, several wireless data communication systems including wireless LAN, wireless home networking, and Bluetooth are described. The four standards for wireless data systems, IEEE 802.11, ETSI HIPERLAN, HomeRF SWAP, and Bluetooth specifications, are briefly described. A section on future trends and challenges is also included in this chapter.
Chapter 10 discusses the networking aspects of wireless Internet. Wireless and Internet are envisioned to merge in the near future. In the introductory part of this chapter, desirable features of future systems are described. High-bit-rate transmission, packet transmission, wireless QoS support for integrated services, voice over IP (VoIP) are listed as desirable features. A section is devoted to Mobile IP and its structure. The author goes into details on mobile IPv4 with route optimization; this is followed by a discussion of Mobile IPv6. An interim architecture is suggested for wireless IP that uses cellular solutions. This chapter also discusses the packet CDMA2000 network, and the use of GPRS/EGPRS for UMTS networks.
Chapter 11 describes digital terrestrial TV broadcasting systems. The EU standard DVB-T is described. This standard uses OFDM for modulation. This chapter also describes the next step of DVB-T called MOTIVATE. MOTIVATE investigates mobile reception techniques for DVB-T. The chapter also introduces the development of HDTV by ATSC. In addition to these two standards, features of a third standard originating from Japan, Integrated Services Digital Broadcasting ? Terrestrial (ISDB-T) are also introduced.
The final chapter deals with IMT-2000 highlighting the challenges of the wireless millennium. The authors describe the needs of the 21st century multimedia society. The chapter goes into details on the evolution of new wireless access technology. The chapter describes desirables features in the new UMTS and how these features impact the spectrum issue. The chapter describes efforts by the authors in evolution of a wideband CDMA system. The chapter also goes into details on enhancements, interference cancellation, adaptive antenna array and its deployment in WCDMA system.
The 321-page book makes a clear distinction between the technological trends and the trends toward development of new systems. The book is more suited to researchers rather than practicing engineers.
