The fi rst edition of this book came about because Regina Lundgren had always been
fascinated with Communication. She started writing novels in the third grade. When she
was asked on her fi rst day at the University of Washington what she hoped to do with her
degree in scientifi c and technical Communication, she replied, “I want to write environ-
mental impact statements.” When Patricia Clark hired her to work at the Pacifi c Northwest
National Laboratory to do just that, she was overjoyed.
Since the first edition of the book was published, the field of modeling and simulation of
Communication systems has grown and matured in many ways, and the use of simulation as a
day-to-day tool is now even more common practice. Many new modeling and simulation
approaches have been developed in the recent years, many more commercial simulation
packages are available, and the evolution of powerful general mathematical applications
packages has provided still more options for computer-aided design and analysis. With the
current interest in digital mobile Communications, a primary area of application of modeling
and simulation is now to wireless systems of a different flavor than the traditional ones.
The goal of this book is to provide a concise but lucid explanation and deriva-
tion of the fundamentals of spread-spectrum Communication systems. Although
spread-spectrum Communication is a staple topic in textbooks on digital com-
munication, its treatment is usually cursory, and the subject warrants a more
intensive exposition. Originally adopted in military networks as a means of
ensuring secure Communication when confronted with the threats of jamming
and interception, spread-spectrum systems are now the core of commercial ap-
plications such as mobile cellular and satellite Communication.
Spread-spectrum Communication is a core area within the field of digital
Communication. Originally used in military networks as countermeasures against
the threats of jamming and interception, spread-spectrum systems are now widely
used in commercial applications and are part of several wireless and mobile
Communication standards. Although spread-spectrum Communication is a staple
topic in textbooks on digital Communication, its treatment is usually cursory. This
book is designed to provide a more intensive examination of the subject that is
suitable for graduate students and practicing engineers with a solid background
in the theory of digital Communication. As the title indicates, this book stresses
principles rather than specific current or planned systems, which are described in
manyotherbooks.My goal in this bookis to providea concisebut lucidexplanation
of the fundamentals of spread-spectrum systems with an emphasis on theoretical
principles.
The continuing vitality of spread-spectrum Communication systems and the devel-
opment of new mathematical methods for their analysis provided the motivation to
undertake this new edition of the book. This edition is intended to enable readers
to understand the current state-of-the-art in this field. Almost twenty percent of the
materialinthiseditionisnew, includingseveralnewsections, anewchapteronadap-
tive arrays and filters, and a new chapter on code-division multiple-access networks.
The remainder of the material has been thoroughly revised, and I have removed a
considerable amount of material that has been superseded by more definitive results.
Visible light Communications (VLC) is the name given to an optical wireless
Communication system that carries information by modulating light in the visible spectrum
(400–700 nm) that is principally used for illumination [1–3]. The Communications signal
is encoded on top of the illumination light. Interest in VLC has grown rapidly with the
growth of high power light emitting diodes (LEDs) in the visible spectrum. The
motivation to use the illumination light for Communication is to save energy by exploiting
the illumination to carry information and, at the same time, to use technology that is
“green” in comparison to radio frequency (RF) technology, while using the existing
infrastructure of the lighting system.
This is a book on wireless Communication. That usually means communica-
tion by radio, though ultrasound and infrared light are also used occasion-
ally. The term “wireless” has come to mean nonbroadcast Communication,
usually between individuals who very often use portable or mobile equip-
ment. The term is rather vague, of course, and there are certainly borderline
applications that are called wireless without falling exactly into the above
definition.
