From the transition of analog to digital communication along with seamless mobility and
high computing power of small handheld devices, the wireless communications industry has
seen tremendous changes leading to the integration of several telecommunication networks,
devices and services over last 30 years. The rate of this progress and growth has increased
particularly in the past decade because people no longer use their devices and networks for
voice only, but demand bundle contents such as data download/streaming, HDTV, HD video ,
3D video conferencing with higher efficiency, seamless connectivity, intelligence, reliability
and better user experience. Although the challenges facing service providers and
telecommunication companies differ by product, region, market size, and their areas of
concentration but time to market, efficient utilization of their assets and revenue expansion,
have impacted significantly how to manage and conduct their business while maintaining
sufficient margin.
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.
This book is intended to help electric power and telephone company
personnel and individuals interested in properly protecting critical tele-
communications circuits and equipment located in high voltage (HV)
environments and to improve service reliability while maintaining safe
working conditions. Critical telecommunications circuits are often
located in HV environments such as electric utility power plants,
substations, cell sites on power towers, and standalone telecommuni-
cations facilities such as 911 call centers and mountaintop telecom-
munications sites.
OSCILLATORS are key building blocks in integrated transceivers. In wired and
wireless communication terminals, the receiver front-end selects, amplifies and
converts the desired high-frequency signal to baseband. At baseband the signal can
then be converted into the digital domain for further data processing and demodula-
tion. The transmitter front-end converts an analog baseband signal to a suitable high-
frequency signal that can be transmitted over the wired or wireless channel.
The third generation (3G) mobile communication system is the next big thing
in the world of mobile telecommunications. The first generation included
analog mobile phones [e.g., Total Access Communications Systems
(TACS), Nordic Mobile Telephone (NMT), and Advanced Mobile Phone
Service (AMPS)], and the second generation (2G) included digital mobile
phones [e.g., global system for mobile communications (GSM), personal
digital cellular (PDC), and digital AMPS (D-AMPS)]. The 3G will bring
digital multimedia handsets with high data transmission rates, capable of
providing much more than basic voice calls.
Mobile multimedia communication is increasingly in demand because of the basic need to communi-
cate at any time, anywhere, using any technology. In addition, to voice communication, people have a
desire to access a range of other services that comprise multimedia elements—text, image, animation,
high fidelity audio and video using mobile communication networks. To meet these demands, mobile
communication technologies has evolved from analog to digital, and the networks have passed through
a number of generations from first generation (1G) to fourth generation (4G).
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.
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.
In Helsinki during a visiting lecture, an internationally well-known professor in communica-
tionssaid,‘Inthecommunicationssocietywehavemanagedtoconvertourproposalsandideas
to real products, not like in the control engineering society. They have very nice papers and
strong mathematics but most of the real systems still use the old PID controllers!’. As our
background is mainly in control as well as communications engineering, we know that this
thought is not very accurate. We agree that most of the practical controllers are analog and
digital PID controllers, simply because they are very reliable and able to achieve the required
control goals successfully. Most of the controllers can be explained in terms of PID. The
reasons behind this impressive performance of PID will be explained in Chapter 2.
