Table Of ContentRADAR
PRINCIPLES
FOR THE
NON-SPECIALIST
RADAR
PRINCIPLES
FOR THE
NON-SPECIALIST
SECOND EDITION
J. C. Toomay
Imil5l Van Nostrand Reinhold
~_~NewYork
Copyright © 1989 by Van Nostrand Reinhold
Softcover reprint of the hardcover 1st edition 1989
Library of Congress Catalog Card Number 88-27982
ISBN-J3: 978-94-011-6987-5 e-ISBN-J3: 978-94-011-6985-1
DOl: 10.1007/978-94-011-6985-1
All rights reserved. Certain portions of this work © 1982 by
Van Nostrand Reinhold. No part of this work covered by the copyright
hereon may be reproduced or used in any form or by any means-graphic,
electronic, or mechanical, including photocopying, recording, taping,
or information storage and retrieval systems-without written permission
of the publisher.
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Library of Congress Cataioging-in-Publication Data
Toomay, J. C. (John C.), 1922-
Radar principles for the non-specialist.
Bibliography: p.
1. Radar. I. Title.
TK6575.T66 1989 621.3848 88-27982
ISBN-J3: 978-94-011-6987-5
PREFACE
What This Book Is
This book is about radar. It will teach you the essentials of radar, the
underlying principles. It is not like an engineering handbook which pro
vides detailed design equations without explaining either derivation or
rationale. It is not like a graduate school textbook which may be abstruse
and esoteric to the point of incomprehensibility. And it is not like an
anthology of popular magazine articles which may be gaudy but superfi
cial. It is an attempt to distill the very complex, rich technology of radar
into its fundamentals, tying them to the laws of nature on one end and to
the most modern and complex systems on the other.
Who It's For
If your work requires you to supervise or meet as coequals with radar
systems engineers or designers, this book will allow you to understand
them, to question them intelligently and perhaps to provide them with a
perspective (a dispassionate yet competent view) that they lack.
If you are trained in another discipline but have been made the man
ager of a radar project or a system program that has one or more radars as
sub-systems, this book will provide you with the tools you need, not only
to give your team members confidence, but also to make a substantive
technical contribution yourself.
If you are intellectually curious about "the way radars work," not
satisfied with a casual explanation, yet without the time to take a course
leading to a master's degree, this book will provide you the level of
comprehension you seek.
For over 20 years, I was associated with scientists, engineers, mathe
maticians, business administration graduates and other college-educated
people, all of whom aspired to jobs with broader responsibilities. Without
exception, these people craved expertise in the various technical areas
their expanding horizons exposed them to. One of the principal technical
areas was radar. (Surprisingly, even the electrical engineers with recent
degrees had no knowledge of radar-which is really a specialty to be
taken up in graduate school.) A rudimentary version ofthis book was put
together in response to that particular situation, but my subsequent expe
rience revealed an even broader need for knowledge of this sort.
v
vi Preface
How It Approaches Radar
Because this book is focused on imparting whole pieces of knowledge,
developed with an evolutionary approach and tied together with a thread
of logic, it starts with electromagnetic propagation, describes a radar of
the utmost simplicity and derives the radar range equation from that
simple radar. Once the range equation is available, the book attacks the
meaning of each term in it, moving through antennas, detection and track
ing, radar cross-section, waveforms and signal processing, and systems
applications in an orderly progression. At the finish, the reader should be
able to do an acceptable, first-order radar design, including some trading
off of design parameters to achieve a more efficient system. But, more
importantly, the reader should know enough to critique the designs of
others and to understand which technical issues are fundamental and
which are simply design frills. While clever design ideas, and acronyms
for them, are rampant, radar functions do not change. Thus, while there is
no way to keep up with each new design wrinkle, knowledge of the
principles that govern them will give instant critical understanding.
What Is Unusual
This book does three things that-although perhaps not unique-are
unusual. It presents a comprehensive set of radar principles-including
all the features of the latest applications-in a relatively short volume. It
presents these principles with their underlying derivations, using the sim
plest mathematics possible, explaining the steps, and using only popularly
tabulated functions, integrals and other expressions. And it uses the same
method of derivation, the same mathematics and the same conceptual
approach to discussing all antennas and all waveforms. Other authors are
aware of the analogs between spatial functions and time functions, and
often cite them, but they do not usually try to develop these concepts as a
single whole.
What Is Useful
This book presents information in logical chunks which are meant to be
self-contained. Most chapters stand alone; the reader may be selective
and still benefit. The chapters are scaled to their information content
rather than the time required to absorb them. Some readers will require
much more effort than others to master a particular chapter. There are
two levels of comprehension provided: The reader may simply memorize
key relationships, which are always identified in the text or may master
Preface vii
the principle and its derivation. Useful references are provided, general
references being preferred. Exercises at the end of each chapter are calcu
lated not to stump the reader, but to reinforce the concepts presented and
illustrate their applications. Nevertheless, with the exception of chapters
on waveforms and systems applications, most readers will find an eve
ning's time sufficient for a chapter.
How It Is Organized
The book goes from the fundamental toward the more complex, and from
philosophy to quantification. Its foundation is the radar range equation, as
the following outline shows:
CHAPTER TITLE PROCESS
Elementary Electromag History, technical funda
netics and The Radar mentals, deriving the
Range Equation Radar Equation
2 Antennas
3 Detection & Tracking
4 Radar Cross Section
Treating terms in the
5 Waveforms & Signal Radar Equation.
Processing
6 Electronic Countermea
sures (ECM)
7 Systems Applications U sing the Radar Equation
8 Loose Ends of Radar Cleaning up loose ends
Lore
9 Radar Potentials and Generalizing on what we
Limitations have learned
J. C. Toomay
SYMBOLS
A, Aeff, A() Area, effective area, ambiguity
a Radius measure
B() Bandwidth or ratio of bandwidth
C, c, c() Circumference, velocity of light, arbitrary
constant
D, d Diameter, distance or separation measure
e Base of the natural logarithm (2.71828)
E Energy
erf(x) The error function of the Normal Distribution
f,fd,6.f Cycle frequency, Doppler frequency, fre
quency difference
G, g Gain
h Altitude, height, Planck's constant
J() Bessel functions
V-l
j
K, k Boltzmann's Constant, wave number (27T/A),
or constant
Length measure
N, n, ii RMS Noise power, number, the mean of a
number
Ne Electron density
No Root-mean-square noise voltage
D() An observation
p() Probability density, probability quantities
p() Points
R(), 6.R, Ro Range measures, range interval, earth radius
r Radius measure
Res, Res Resolution and maximum resolution
max
s
RMS signal power
ix
x Symbols
S/J Signal-to-jamming noise ratio
SL Sidelobe level
SIN Signal-to-noise ratio
(SINh Total signal-to-noise ratio
T, Ts, !1T, t, to, !1t Time, system temperature, rise time of a
pulse, the tabulated variable for erf (x), inte
gration time, time interval
v, Vs Volume or voltage, peak signal voltage
v, !1v Velocity, velocity interval, or voltage differ
ence
Dependent variable, sample mean
A verage after n observations
Angle measure or Type I statistical error
Phase, bandwidth, or Type II statistical error
Pointing angle, gain over clutter
An interval of time (pulse repetition interval)
An interval of frequency (pulse repetition
frequency)
A measure of deviation
e,e; An arbitrarily small increment, error
Index of refraction, quantum efficiency
YJ
8, !18 Angle measure, beamwidth, parameter in
exponential distribution, small difference in
angle
Wavelength
Collision frequency
JJ
Pi (3.14159)
p Reflectivity
Radar cross section (RCS) or statistical stan
dard deviation, peak RCS, average RCS,
initial RCS, clutter velocity spread, clutter
RCS per unit area
Pulse duration
7
Angle measure, phase measure
Symbols xi
Reflection coefficient (power)
Solid angle, Faraday rotation
w Radian Frequency (27T f)
Total Power
Clutter cancellation ratio
Distance
Description:What This Book Is This book is about radar. It will teach you the essentials of radar, the underlying principles. It is not like an engineering handbook which pro vides detailed design equations without explaining either derivation or rationale. It is not like a graduate school textbook which may
