Emerging technologies such as WiFi and WiMAX are profoundly changing the
landscape of wireless broadband. As we evolve into future generation wireless
networks, a primary challenge is the support of high data rate, integrated multi-
media type traffic over a unified platform. Due to its inherent advantages in
high-speed communication, orthogonal frequency division multiplexing (OFDM)
has become the modem of choice for a number of high profile wireless systems
(e.g., DVB-T, WiFi, WiMAX, Ultra-wideband).
Over the past few decades, wireless communications and networking have witnessed an
unprecedented growth, and have become pervasive much sooner than anyone could have
predicted. For example, cellular wireless networks are expected to become the dominant
and ubiquitous telecommunication means in the next few decades. The widespread
success of cellular and WLAN systems prompts the development of advanced wireless
systems to provide access to information services beyond voice such as telecommuting,
video conferencing, interactive media, real-time internet gaming, and so on, anytime
and anywhere.
When the authors of this book asked me to write the foreword of
their work on the digital enterprise, I immediately thought that it was
one more document on a fashionable topic in the technology and the
business world of the 21st Century often addressed by consulting
firms, some of which have aspired to become experts on the subject.
However, a more careful observation reveals that an issue more
important than the sole subject of the digital enterprise is: “Is your
company fully operational?”, because this is the real topic.
Wireless Fidelity (Wi-Fi) networks have become mainstream over the last few years. What
started out as cable replacement for static desktops in indoor networks has been extended
to fully mobile broadband applications involving moving vehicles, high-speed trains, and
even airplanes.
Communication today is not as easy as it was in the past. Protecting numerous com-
munication services, which are operating in the same or adjacent communication
channels, has become increasingly challenging. Communication systems have to be
protected from both natural and manmade interference. Electromagnetic interfer-
ence can be radiated or conducted, intentional or unintentional.
Cellular communications is one of the fastest growing and most challenging telecom-
munication applications ever. Today, it represents a large and continuously increasing
percentage of all new telephone subscribers around the world. In the long term,
cellular digital technology may become the universal way of communication.
The wireless market has experienced a phenomenal growth since the first second-
generation (2G) digital cellular networks, based on global system for mobile
communications (GSM) technology, were introduced in the early 1990s. Since then,
GSM has become the dominant global 2G radio access standard. Almost 80% of today’s
new subscriptions take place in one of the more than 460 cellular networks that use
GSM technology. This growth has taken place simultaneously with the large experienced
expansion of access to the Internet and its related multimedia services.
Communication, a word that many associate with modern technology, actually
has nothing to do with technology. At its core, communication involves nothing
more than the spoken or written word, and symbolic languages like art and music.
Technology has become synonymous with communication because technology
has historically been the method by which communication to or by the general
population takes place.
Smartphones have become a key element in providing greater user access to the
mobile Internet. Many complex applications which used to be limited to PCs, have
been developed and operated on smartphones. These applications extend the
functionalities of smartphones, making them more convenient for users to be
connected. However, they also greatly increase the power consumption of
smartphones, making users frustrated with long delays in Web browsing.
In recent years, the research and developments in the area of RF and microwave
technologies have progressed significantly due to the growing demand for applica-
bility in wireless communication technologies. Starting from 1992, wireless com-
munication technologies have become quite mature. In the modern era of electronic
developments, design of wireless handsets is an example of integration of many di-
verse skill sets. Classical books in the areas of microwave technology provide us
with an in-depth knowledge of electromagnetic fundamentals.
