Orthogonal frequency division multiplexing (OFDM) has been shown to be
an effective technique to combat multipath fading in WIRELESS channels. It
has been and is going to be used in various WIRELESS communication systems.
This book gives a comprehensive introduction on the theory and practice of
OFDM for WIRELESS communications.
Recent decades have shown a tremendous expansion of the Internet. The number of
connected terminals has increased by orders of magnitude, traffic has grown exponen-
tially, coverage has become ubiquitous and worldwide, and today’s sophisticated Web
2.0 applications are increasingly providing services which hitherto have been the realm
of telecommunications, such as Skype and video conferencing. This has even led to the
thought that access to the Internet might one day be a universal right of every citizen.
This evolution will accelerate in the coming decades.
This book is intended for the graduate or advanced undergraduate
engineer. The primary motivation for developing the text was to present a
complete tutorial of phase-locked loops with a consistent notation. I believe
this is critical for the practicing engineer who uses the text as a self-study
guide.
This book focuses on the study and development of one of the most
advanced topics in broadband WIRELESS communications systems:
power efficiency and power consumption in WIRELESS communications
systems, especially of mobile devices. Hence, the main focus of this
book is on the most recent techniques for the conservation of power
and increase in power efficiency.
This book stems from its ancestor Digital Transmission Theory,published by
Prentice-Hall in 1987 and now out of print. Following the suggestion of several colleagues who complained about the unavailability of a textbook they liked and adopted in their courses, laying a strong emphasis on WIRELESS communication. We hope that those who liked the previous book will find again its flavor here,while new reader, untouched by nostalgia, will judge it favorably.
The investigation of the propagation channel is becoming more and more important in mod-
ern WIRELESS communication. The demand for spectral efficiency motivates exploitation of
all channels that can possibly be used for communications. Nowadays, a common trend for
designing physical layer algorithms is to adapt the transceiving strategy, either by maximizing
the diversity gains or by utilizing the coherence of the channels to improve the signal-to-noise
power ratio.
Radio propagation measurements and channel modelling continue to be of fundamental importance
to radio system design. As new technology enables dynamic spectrum access and higher data rates,
radio propagation effects such as shadowing, the presence of multipath and frequency dispersion
are the limiting factors in the design of WIRELESS communication systems. While there are several
books covering the topic of radio propagation in various frequency bands, there appears to be no
books on radio propagation measurements, which this book addresses at length.
This book provides the essential design techniques for radio systems that
operate at frequencies of 3 MHz to 100 GHz and which will be employed in
the telecommunication service. We may also call these WIRELESS systems,
WIRELESS being synonymous with radio, Telecommunications is a vibrant indus-
try, particularly on the ‘‘radio side of the house.’’ The major supporter of this
upsurge in radio has been the IEEE and its 802 committees. We now devote
? . an entire chapter to WIRELESS LANs WLANs detailed in IEEE 802.11. We
also now have subsections on IEEE 802.15, 802.16, 802.20 and the WIRELESS
? . ? metropolitan area network WMAN . WiFi, WiMax,, and UWB ultra wide-
. band are described where these comparatively new radio specialties are
demonstrating spectacular growth.
By inventing the WIRELESS transmitter or radio in 1897, the Italian physicist Tomaso
Guglielmo Marconi added a new dimension to the world of communications. This
enabled the transmission of the human voice through space without wires. For this
epoch-making invention, this illustrious scientist was honored with the Nobel Prize
for Physics in 1909. Even today, students of WIRELESS or radio technology remember
this distinguished physicist with reverence. A new era began in Radio
Communications.
It was only a few years ago that “ubiquitous connectivity” was recognized as the future of
WIRELESS communication systems. In the era of ubiquitous connectivity, it was expected that
the broadband mobile Internet experience would be pervasive, and seamless connectivity on
a global scale would be no surprise at all. The quality of service would be guaranteed no
matter when/where/what the users wanted with the connectivity. Connectivity would even be
extended to object-to-object communication, where no human intervention was required. All
objects would become capable of autonomous communication.
