This book is exclusively dedicated to WiMAX. The focus of the book is
on the applications of WiMAX networks, with delivery of multimedia
content to wireless and mobile devices being the area of greatest atten-
tion. WiMAX has crossed a number of major milestones in the recent
past.
One of the very first books published on the social impact of the mobile phone
was Timo Kopomaa’s The City in Your Pocket: Birth of the Mobile Information Society.
The book, published in 2000, was based on research that Kopomaa had under-
taken for Nokia and Sonera as part of his doctoral studies in the Centre for Urban
and Regional Studies at the Helsinki University of Technology. The first line he
writes in the book is peculiar: ‘Mobile communication is not a serious matter’. By
this, we assume he is referring to a view of the world that would regard the mobile
phone as little more than an unremarkable fact of everyday life – a simple play-
thing for the young, or a productivity tool for the business executive and busy
parent.
The insinuation of telecommunications into the daily fabric of our lives has been
arguably the most important and surprising development of the last 25 years. Before
this revolution, telephone service and its place in our lives had been largely stable
for more than a generation. The growth was, so to speak, lateral, as the global reach
of telecommunications extended and more people got telephone service. The
distinction between oversea and domestic calls blurred with the advances in
switching and transmission, undersea cable, and communication satellites. Traffic
on the network remained overwhelmingly voice, largely in analog format with
facsimile (Fax) beginning to make inroads.
Since the principle of multi-carrier code division multiple access (MC-CDMA) was
simultaneously proposed by Khaled Fazel et al. and Nathan Yee et al. at the IEEE
International Symposium on Personal, Indoor and Mobile Radio Communications
(PIMRC) in the year 1993, multi-carrier spread spectrum (MC-SS) has rapidly become
one of the most wide spread independent research topics on the field of mobile radio
communications. Therefore, the International Workshop on Multi-Carrier Spread
Spectrum (MC-SS) was initiated in the year 1997. Multi-carrier and spread spectrum
systems with their generic air interface and adaptive technologies are considered as
potential candidates to fulfill the requirements of next generation mobile communications
systems.
In case you haven’t noticed, multimedia communication over IP and wireless net-
works is exploding. Applications such as BitTorrent, used primarily for video
downloads, now take up the lion’s share of all traffic on the Internet. Music file
sharing, once on the legal cutting edge of massive copyright infringement on col-
lege campuses around the world, has moved into the mainstream with signifi-
cant legal downloads of music and video to devices such as the iPod and nu-
merous other portable media players.
Many wireless communications channels consist of multiple signal paths from the
transmitter to receiver. This multiplicity of paths leads to a phenomenon known
as multipath fading. The multiple paths are caused by the presence of objects in the
physical environment that, through the mechanisms of propagation, alter the path of
radiated energy. These objects are referred to as scatterers. In the past, researchers
often looked at ways to mitigate multipath scattering, such as in diversity systems.
Multiple-input, multiple-output (MIMO) systems, on the other hand, use multipath
diversity to their advantage; a MIMO system has the ability to translate increased
spatial diversity into increased channel capacity.
Coverage of routing techniques in various wired and wireless networks is the unique
proposition of this book. Routing protocols and algorithms are the brains of any network.
The selection of topics in this book is clear: we attempt to explain routing in its entirety,
starting from fundamental concepts, then moving through routing on the Internet, and
finally cutting across the recent‐day cellular, ad hoc, and wireless networks.
Theartofcomputationofelectromagnetic(EM)problemshasgrownexponentially
for three decades due to the availability of powerful computer resources. In spite of
this, the EM community has suffered without a suitable text on the computational
techniques commonly used in solving EM-related problems. Although there have
been monographs on one particular technique or another, the monographs are written
for the experts rather than students. Only a few texts cover the major techniques and
dothatinamannersuitableforclassroomuse.Itseemsexpertsinthisareaarefamiliar
with one or a few techniques but not many seem to be familiar with all the common
techniques. This text attempts to fill that gap.
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.
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.
