Microwave radio network design is a subset of activities that constitute
the overall transmission network design. Transmission networks are
sometimes called transport networks, access networks, or connectivity
networks. For many wireless carriers, microwave is becoming a popu-
lar preference over wireline (leased lines) transport for many reasons,
especially as microwave radio equipment costs decrease and installation
becomes simpler. Low monthly operating costs can undercut those of
typical single (and especially multiple) T1/E1 expenses, proving it to be
more economical over the long term—usually two to four years. Network
operators also like the fact that they can own and control microwave
radio networks instead of relying on other service providers for network
components.
Transmit power in wireless cellular networks is a key degree of freedom
in the management of interference, energy, and connectivity. Power
control in both uplink and downlink of a cellular network has been
extensively studied, especially over the last 15 years, and some of the
results have enabled the continuous evolution and significant impact of
the digital cellular technology.
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.
Radio frequency spectrum is a scarce and critical natural resource that is utilized for
many services including surveillance, navigation, communication, and broadcast-
ing. Recent years have seen tremendous growth in the use of spectrum especially by
commercial cellular operators. Ubiquitous use of smartphones and tablets is one
of the reasons behind an all-time high utilization of spectrum. As a result, cellular
operators are experiencing a shortage of radio spectrum to meet bandwidth
demands of users. On the other hand, spectrum measurements have shown that
much spectrum not held by cellular operators is underutilized even in dense urban
areas. This has motivated shared access to spectrum by secondary systems with no
or minimal impact on incumbent systems. Spectrum sharing is a promising
approach to solve the problem of spectrum congestion as it allows cellular operators
access to more spectrum in order to satisfy the ever-growing bandwidth demands of
commercial users.
The use of mobile devices now surpasses that of traditional computers: wireless
users will hence soon be demanding the same rich multimedia services on their
mobile devices that they have on their desktop personal computers. In addition,
new services will be added, especially related with their mobile needs, such as
location-based information services.
n the first part of this book, we give an introduction to the basic applications of wireless com-
munications, as well as the technical problems inherent in this communication paradigm. After a
brief history of wireless, Chapter 1 describes the different types of wireless services, and works
out their fundamental differences. The subsequent Section 1.3 looks at the same problem from
a different angle: what data rates, ranges, etc., occur in practical systems, and especially, what
combination of performance measures are demanded (e.g., what data rates need to be transmitted
over short distances; what data rates are required over long distances?) Chapter 2 then describes
the technical challenges of communicating without wires, putting special emphasis on fading and
co-channel interference. Chapter 3 describes the most elementary problem of designing a wireless
system, namely to set up a link budget in either a noise-limited or an interference-limited system.
After studying this part of the book, the reader should have an overview of different types of
wireless services, and understand the technical challenges involved in each of them. The solutions
to those challenges are described in the later parts of this book.
This book on electrostatic discharge phenomena is essentially a translation and
update ofa Swedish edition from 1992.
The book is intended for people working with electronic circuits and
equipments, in application and development. All personnel should be aware of the
ESD-hazards, especially those responsible for quality. ESD-prevention is a part of
TQM (Total Quality Management). The book is also usable for courses on the
subject.
ESD is a crucial factor for integrated circuits and influences their quality and reliability.
Today increasingly sensitive processes with deep sub micron structures are developed. The
integration of more and more functionality on a single chip and saving of chip area is
required. Integrated circuits become more susceptible to ESD/EOS related damages.
However, the requirements on ESD robustness especially for automotive applications are
increasing. ESD failures are very often the reason for redesigns. Much research has been
conducted by semiconductor manufacturers on ESD robust design.
In the present era, low observability is one of the critical requirements in aerospace
sector, especially related to defense. The stealth technology essentially relates to
shaping and usage of radar absorbing materials (RAM) or radar absorbing struc-
tures (RAS). The performance of such radar cross section (RCS) reduction tech-
niques is limited by the bandwidth constraints, payload requirements, and other
structural issues. Moreover, with advancement of materials science, the structure
geometry no longer remains key decisive factor toward stealth.
In this research, we have designed, developed implemented a wireless sensor
networks based smart home for safe, sound and secured living environment for
any inhabitant especially elderly living alone. We have explored a methodology
for the development of efficient electronic real time data processing system to
recognize the behaviour of an elderly person. The ability to determine the
wellness of an elderly person living alone in their own home using a robust,
flexible and data driven artificially intelligent system has been investigated. A
framework integrating temporal and spatial contextual information for
determining the wellness of an elderly person has been modelled. A novel
behaviour detection process based on the observed sensor data in performing
essential daily activities has been designed and developed.