The continued reduction of integrated circuit feature sizes and
commensurate improvements in device performance are fueling the progress
to higher functionality and new application areas. For example, over the last
15 years, the performance of microprocessors has increased 1000 times.
Analog circuit performance has also improved, albeit at a slower pace. For
example, over the same period the speed/resolution figure-of-merit of
analog-to-digital converters improved by only a factor 10.
The General Packet Radio Service (GPRS) allows an end user to send and
receive data in packet transfer mode within a public land mobile network
(PLMN) without using a permanent connection between the mobile station
(MS) and the external network during data transfer. This way, GPRS opti-
mizes the use of network and radio resources (RRs) since, unlike circuit-
switched mode, no connection between the MS and the external network is
established when there is no data flow in progress. Thus, this RR optimiza-
tion makes it possible for the operator to offer more attractive fees.
There have been many advances in communication circuits since the publication of the first edition of this book.Yet most of communication circuit fundamentals remain intact.Amplifier,oscillator , tuned circuits,transformers,mixers and power amplifiers still among fundamental building blocks of communication circuits.
Modeling and simulation of nonlinear systems provide communication system designers
with a tool to predict and verify overall system performance under nonlinearity and
complex communication signals. Traditionally, RF system designers use deterministic
signals (discrete tones), which can be implemented in circuit simulators, to predict the
performance of their nonlinear circuits/systems. However, RF system designers are usually
faced with the problem of predicting system performance when the input to the system
is real-world communication signals which have a random nature.
Soon after Samuel Morse’s telegraphing device led to a deployed electri-
cal telecommunications system in 1843, waiting lines began to form by those
wanting to use the system. At this writing queueing is still a significant factor in
designing and operating communications services, whether they are provided
over the Internet or by other means, such as circuit switched networks.
It is more than a decade since GSM was first commercially available. After some unexpected delay, it
seems that finally UMTS is here to stay as a 3G system standardised by 3GPP, at least for another ten
years. UMTS will enable multi-service, multi-rate and flexible IP native-based mobile technologies to be
used in wide area scenarios and also pave the way for a smooth transition from circuit switched voice
networks to mobile packet services.
Cognitive radios have become a vital solution that allows sharing of the scarce
frequency spectrum available for wireless systems. It has been demonstrated
that it can be used for future wireless systems as well as integrated into 4G/5G
wireless systems. Although there is a great amount of literature in the design of
cognitive radios from a system and networking point of view, there has been very
limited available literature detailing the circuit implementation of such systems.
Our textbook, Radio Frequency Integrated Circuit Design for Cognitive Radios, is
the first book to fill a disconnect in the literature between Cognitive Radio systems
and a detailed account of the circuit implementation and architectures required to
implement such systems. In addition, this book describes several novel concepts
that advance state-of-the-art cognitive radio systems.
The ability to analyze system or circuit behavior is one of the key requirements for
successful design. To put an idea to work, a designer needs both the knowledge
and tools for analyzing the behavior of that new system architecture or that experi-
mental circuit topology. Design decisions are grounded on the results obtained from
analysis.
The first edition of this book was published in 1992. Nine years later it had become
clear that a second edition was required because of the rapidly changing nature of
telecommunication. In 1992, the Internet was in existence but it was not the
household word that it is in the year 2001. Cellular telephones were also in use
but they had not yet achieved the popularity that they enjoy today. In the current
edition, Chapter 1 has been revised to include a section on the Internet. Chapter 10 is
new and it covers the facsimile machine; I had overlooked this important tele-
communication device in the first edition. Chapter 11 is also new and it describes the
pager, the cordless telephone and the cellular telephone system. These are examples
of a growing trend in telecommunications to go ‘‘wireless’’.
Long-TermEvolution(LTE)isarguablyoneofthemostimportantstepsinthecurrentphaseof
the development of modern mobile communications. It provides a suitable base for enhanced
services due to increased data throughput and lower latency figures, and also gives extra
impetus to the modernization of telecom architectures. The decision to leave the circuit-
switched domainoutofthescope ofLTE/SAEsystem standardization might soundradical but
itindicatesthatthetelecomworldisgoingstronglyfortheall-IPconcept----andthedeployment
of LTE/SAE is concrete evidence of this global trend.
