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means of a combination of applications and performance curves. Problem setsare provided for those seeking additional training. Starred sections containingbasic mathematical development may be skipped with no loss of continuity bythose seeking only a qualitative understanding. The book is intended forelectrical, electronics, and communication engineering students, as well aspracticing engineers wishing to familiarize themselves with the broad field ofinformation transmission, particularly satellite communications.The first of the book’s eight chapters covers the basic principles ofsatellite communications, including message security (cryptology).Chapter 2 discusses the technical fundamentals for satellite communicationsservices, which do not change as rapidly as technology and provides thereader with the tools necessary for calculation of basic orbit characteristicssuch as period, dwell time, and coverage area; antenna system specificationssuch as type, size, beam width, and aperture-frequency product; and powersystem design. The system building blocks comprising satellite transponderand system design procedure are also described. While acknowledging thatsystems engineering is a discipline on its own, it is my belief that the readerwill gain a broad understanding of system engineering design procedure,accumulated from my experience in large, complex turnkey projects.Earth station, which forms the vital part of the overall satellite system, isthe central theme of Chapter 3. The basic intent of data transmission is toprovide quality transfer of information from the source to the receiver withminimum error due to noise in the transmission channel. To ensure qualityinformation requires smart signal processing technique (modulation) andefficient use of system bandwidth (coding, discussed extensively in Chapter6). The most popular forms of modulation employed in digital communications,such as BPSK, QPSK, OQPSK, and 8-PSK, are discussed together withtheir performance criteria (BER). An overview of information theory is givento enhance the reader’s understanding of how maximum data can be transmittedreliably over the communication medium. Chapter 3 concludes bydescribing a method for calculating system noise temperature and the itemsthat facilitate primary terrestrial links to and from the Earth stations.Chapter 4 discusses the process of designing and calculating the carrierto-noiseratio as a measure of the system performance standard. The quality ofsignals received by the satellite transponder and that retransmitted andreceived by the receiving earth station is important if successful informationtransfer via the satellite is to be achieved. Within constraints of transmitterpower and information channel bandwidth, a communication system must bedesigned to meet certain minimum performance standards. The most importantperformance standard is ratio of the energy bit per noise density in theCopyright © 2002 by Marcel Dekker, Inc. All Rights Reserved.
Page 2: SatelliteCommunicationEngineeringMi
Page 6: This book is dedicated to my famili
Page 10: Because of the immense importance o
Page 16: information channel, which carries
Page 20: ContentsSeries IntroductionPrefaceK
Page 24: 6. Error Detection and Correction C
Page 28: position location in order to insta
Page 32: FIGURE 1.1Intercontinental communic
Page 36: 3. Satellite circuits in a common c
Page 40: decryption algorithm D y with the c
Page 44: earthstations, RS( j) (more issaid
Page 48: Technology developed an advanced en
Page 52: FIGURE 1.8Sequence of the transform
Page 56: TABLE 1.1The DES Selection Function
Page 60: and the 32-bit block input isY ¼ y
Page 64:
communication package placed in orb
Page 68:
2Satellites2.1 OVERVIEWA satellite
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stable over their operating tempera
Page 76:
FIGURE 2.3 Geometric properties of
Page 80:
at the altitudes of satellites, the
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whereg ¼ acceleration due to gravi
Page 88:
2.3 COVERAGE AREA AND SATELLITENETW
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The apex angle required at the sate
Page 96:
the frontline satellites is then pa
Page 100:
station antenna must be pointed to
Page 104:
and the azimuth angle is a z ¼ 180
Page 108:
2.5.3 Swath WidthThe width of the v
Page 112:
2.6.3 System Speci¢cations: Analys
Page 116:
Like all materials that require cou
Page 120:
By the first definition, the system
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SolutionFrom (2.28), we can estimat
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FIGURE 2.11An example of redundancy
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adiators. An antenna array is a fam
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Example 2.3: The earth subtends an
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eam is assumed symmetrical (i.e., y
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FIGURE 2.15Feed array elements ðy
Page 148:
If the steering is in the direction
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2.8 SATELLITE POWER SYSTEMSA key co
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Calculate (1) the probability that
Page 160:
FIGURE 2.20Carrier processing.infor
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FIGURE 2.22(d) elliptic.Types of ba
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FIGURE 2.23A klystron. (Courtesy of
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FIGURE 2.25A simple block diagram o
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tional protection is required to en
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3.1 BASIC PRINCIPLE OF EARTH STATIO
Page 184:
3.1.1 Technical and Operational Req
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excellent protection against noise
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FIGURE 3.3QPSK modulator.FIGURE 3.4
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TABLE 3.28-PSK Truth TableInput bit
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FIGURE 3.8An M-ary PSK demodulator
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where B is the allocated channel ba
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A frequently used function is the Q
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In view of (3.11), Eq. (3.18) can b
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Encoder and DecoderAn encoder is an
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Modulator and DemodulatorA modulato
Page 224:
Zero Forcing Technique. Suppose the
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The adjoint of matrix A is obtained
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FIGURE 3.14The three-tap equalizer
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First, in the case of digital signa
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than 1=A. Whichever law is used, th
Page 244:
FIGURE 3.16Block diagram for estima
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3.4.2 Antenna TrackingAn earth stat
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controlling antenna pointing. The m
Page 256:
FIGURE 3.19A generalized model of a
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FIGURE 3.20Entropy of a binary sour
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whereHðYÞ¼output entropy, the av
Page 268:
To have a feel for this expression,
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2. The system’s overall condition
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transmitted down the fiber as digit
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10. Kantor, L. Y. (ed). (1987). Han
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142. Simulate the probability of bi
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FIGURE 4.1A simplex link.baseband c
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Chapter 2, Sec. 2.7, discusses that
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From (4.6), the received power P r
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FIGURE 4.3A model of the combined-l
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4.1.2 Rain AttenuationRain attenuat
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FIGURE 4.5rates.Average rainstorm p
Page 312:
FIGURE 4.6Adjacent satellite interf
Page 316:
FIGURE 4.8Satellite separation dist
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inability of satellite A to accurat
Page 324:
FIGURE 4.10 Cross-link E b =N 0 vs.
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Then using (4.41), the overall C=N
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(iv)(v)(vi)(vii)Calculate the recei
Page 336:
5Communication Networks andSystemsC
Page 340:
discriminate among carriers by temp
Page 344:
FIGURE 5.2 Principle of FDMA system
Page 348:
FIGURE 5.3 Operational concept of T
Page 352:
FIGURE 5.5TDMA: bit rate r b for 1
Page 356:
Copyright © 2002 by Marcel Dekker,
Page 360:
5.2 CAPACITY COMPARISON OFMULTIPLE-
Page 364:
Rearranging (5.11) in terms of ener
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The transmission bit rate isR r ¼
Page 372:
6Error Detection and CorrectionCodi
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the channel and reconstruct the sou
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message sequence X . Thus, a system
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If we consider a message X ¼ð1010
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can be seen in Table 6.1 that the m
Page 392:
FIGURE 6.1A (7, 4) cyclic code gene
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FIGURE 6.2Convolutional codes encod
Page 400:
Alternative methods of describing a
Page 404:
FIGURE 6.5 Code tree diagram of Fig
Page 408:
FIGURE 6.8 Code tree diagram of rat
Page 412:
consistent with the constraint leng
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trellis depth is approximated to 5L
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FIGURE P.1A convolutional coder.the
Page 424:
7Regulatory Agencies andProceduresT
Page 428:
of the radiofrequency spectrum, and
Page 432:
The CCIR works through the medium o
Page 436:
7.1.3 IFRBThe International Frequen
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The national or regional spectrum m
Page 444:
3. The need to expand or enhance th
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The DSP will be responsible for res
Page 452:
2. Provide a convenient framework w
Page 456:
FIGURE 8.3Types of user-to-network
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H1-channels are designed to carry v
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information. The transfer cell prov
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The OSI layers are divided into two
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plane is denoted by U, the control
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interfacing, maintenance, and conne
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adjoining base station to scan the
Page 484:
FIGURE 8.9Geometry of a polygon.The
Page 488:
FIGURE 8.11Splitting cells into sma
Page 492:
causes signal fading. Of course, th
Page 496:
FIGURE 8.14TCP=IP suite and its rel
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access to an Internet point of pres
Page 504:
message security via satellite is d
Page 508:
REFERENCES1. Wu, W.W. (1989). Eleme
Page 512:
Appendix ANotationsThe symbols have
Page 516:
N sPP rP sP TRRðtÞR cR eR rR vSS
Page 520:
g Central anglez Channel gainZ Ante
Page 524:
AttenuationBandwidthBearer serviceB
Page 528:
Frequency divisionmultiple accessFr
Page 532:
MultiplexingNetworkOmnidirectionala
Page 536:
UplinkUser-to-networkinterfaceThe e
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