Rapid growth of wireless communication services in recent decades has created
a huge demand of radio spectrum. Spectrum scarcity and utilization inefficiency
limit the development of wireless networks. Cognitive radio is a promising tech-
nology that allows secondary users to reuse the underutilized licensed spectrum of
primary users. The major challenge for spectrum sharing is to achieve high spectrum
efficiency while making non-intrusive access to the licensed bands. This requires in-
formation of availability and quality of channel resources at secondary transmitters,
however, is difficult to be obtained perfectly in practice.
This book is an outgrowth of the pioneering development work done by InterDigital Com-
munication Corporation in 3rd Generation TDD WCDMA Technology. Many engineers
and managers were involved in this development, which spanned a wide range of tech-
nology areas, including system architecture, radio interface, radio modem design, radio
resource management and hardware/software implementation. In addition, TDD WCDMA
technology had many direct and indirect contributors across the globe in the context of
the development of the 3GPP TDD WCDMA Standard.
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.
District energy (DE) systems use central heating and/or cooling facilities to provide
heating and/or cooling services for communities. The advantages of district energy
over conventional heating and cooling include improved efficiency, reliability and
safety, reduced environmental impact, and for many situations better economics.
DE systems can be particularly beneficial when integrated with cogeneration plants
for electricity and heat, i.e., with combined heat and power (CHP) plants. One of
the main impediments to increased use of cogeneration-based district energy is a
lack of understanding of the behavior of integrated forms of such systems. This
book is aimed at providing information on district energy and cogeneration tech-
nologies, as well as systems that combine them.
Recent years have seen a rapid development of neural network control tech-
niques and their successful applications. Numerous simulation studies and
actual industrial implementations show that artificial neural network is a good
candidate for function approximation and control system design in solving the
control problems of complex nonlinear systems in the presence of different kinds
of uncertainties. Many control approaches/methods, reporting inventions and
control applications within the fields of adaptive control, neural control and
fuzzy systems, have been published in various books, journals and conference
proceedings.
