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information channel, which carries the signals in a format in which they aredelivered to the end users.To broadcast video, data, and=or audio signals over a wide area to manyusers, a single transmission to the satellite is repeated and received by multiplereceivers. While this might be a common application of satellites, there areothers which may attempt to exploit the unique capacity of a satellite mediumto create an instant network and connectivity between any points within itsview. To exploit this geometric advantage, it is necessary to create a system ofmultiple accesses in which many transmitters can use the same satellitetransponder simultaneously. Chapter 5 discusses the sharing techniquescalled multiple access. Sharing can be in many formats, such as sharing thetransponder bandwidth in separate frequency slots (FDMA), sharing thetransponder availability in time slots (TDMA), or allowing coded signals tooverlap in time and frequency (CDMA). The relative performance of thesesharing techniques is discussed.Chapter 6 explores the use of error-correcting codes in a noisy communicationenvironment, and how transmission error can be detected andcorrection effected using the forward error correction (FEC) methods,namely, the linear block and convolutional coding techniques. Examples aresparingly used as illustrative tools to explain the FEC techniques.The regulation that covers satellite networks occurs on three levels:international, regional, and national. Chapter 7 discusses the interactionamong these three regulatory levels.Customer’s demands for personalized services and mobility, as well asprovision of standardized system solutions, have caused the proliferation oftelecommunications systems. Chapter 8 examines basic mobile-satellitesystemservices and their interaction with land-based backbone networks—inparticular the integrated service digital network (ISDN). Since the servicescovered by ISDN should also, in principle, be provided by digital satellitenetwork, it is necessary to discuss in some detail the basic architecture ofISDN as well as its principal functional groups in terms of referenceconfigurations, applications, and protocols. Chapter 8 concludes by brieflylooking at cellular mobile system, including cell assignment and internetworkingprinciples, as well as technological obstacles to providing efficient Internetaccess over satellite links.The inspiration for writing Satellite Communication Engineering comespartly from my students who have wanted me to share the wealth of myexperience acquired over the years and to ease their burden in understandingthe fundamental principles of satellite communications. A very special thanksgo to my darling wife, Dr. Marjorie Helen Kolawole, who actively reminds meCopyright © 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 14: means of a combination of applicati
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
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FIGURE 2.3 Geometric properties of
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at the altitudes of satellites, the
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whereg ¼ acceleration due to gravi
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2.3 COVERAGE AREA AND SATELLITENETW
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The apex angle required at the sate
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the frontline satellites is then pa
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station antenna must be pointed to
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and the azimuth angle is a z ¼ 180
Page 108:
2.5.3 Swath WidthThe width of the v
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2.6.3 System Speci¢cations: Analys
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Like all materials that require cou
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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
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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
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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
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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
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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
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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
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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
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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
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FIGURE 4.6Adjacent satellite interf
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FIGURE 4.8Satellite separation dist
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inability of satellite A to accurat
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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
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5Communication Networks andSystemsC
Page 340:
discriminate among carriers by temp
Page 344:
FIGURE 5.2 Principle of FDMA system
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FIGURE 5.3 Operational concept of T
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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
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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
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Alternative methods of describing a
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FIGURE 6.5 Code tree diagram of Fig
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FIGURE 6.8 Code tree diagram of rat
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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
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7Regulatory Agencies andProceduresT
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of the radiofrequency spectrum, and
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The CCIR works through the medium o
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7.1.3 IFRBThe International Frequen
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The national or regional spectrum m
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3. The need to expand or enhance th
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The DSP will be responsible for res
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2. Provide a convenient framework w
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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
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FIGURE 8.9Geometry of a polygon.The
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FIGURE 8.11Splitting cells into sma
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causes signal fading. Of course, th
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FIGURE 8.14TCP=IP suite and its rel
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access to an Internet point of pres
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message security via satellite is d
Page 508:
REFERENCES1. Wu, W.W. (1989). Eleme
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Appendix ANotationsThe symbols have
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N sPP rP sP TRRðtÞR cR eR rR vSS
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g Central anglez Channel gainZ Ante
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AttenuationBandwidthBearer serviceB
Page 528:
Frequency divisionmultiple accessFr
Page 532:
MultiplexingNetworkOmnidirectionala
Page 536:
UplinkUser-to-networkinterfaceThe e
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