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position location in order to instantaneously return an upwardly transmitting(uplink) ranging waveform for tracking from an earth terminal (or station).The term earth terminal refers collectively to the terrestrial equipmentcomplex concerned with transmitting signals to and receiving signals fromthe satellite. The earth terminal configurations vary widely with various typesof systems and terminal sizes. An earth terminal can be fixed and mobile landbased,sea-based, or airborne. Fixed terminals, used in military and commercialsystems, are large and may incorporate network control center functions.Transportable terminals are movable but are intended to operate from a fixedlocation, that is, a spot that does not move. Mobile terminals operate while inmotion; examples are those on commercial and navy ships as well as those onaircraft. Chapter 3 addresses a basic earth terminal configuration.Vast literature has been published on the subject of satellite communications.However, the available literature appears to deal specifically withspecialized topics related to communication techniques, design or partsthereof, or satellite systems as a whole.This chapter briefly looks at the development and principles of satellitecommunication and its characteristic features.1.1 THE ORIGIN OF SATELLITESThe Space Age began in 1957 with the U.S.S.R.’s launch of the first artificialsatellite, called Sputnik, which transmitted telemetry information for 21 days.This achievement was followed in 1958 by the American artificial satelliteScore, which was used to broadcast President Eisenhower’s Christmasmessage. Two satellites were deployed in 1960: a reflector satellite, calledEcho, and Courier. The Courier was particularly significant because itrecorded a message that could be played back later. In 1962 active communicationsatellites (repeaters), called Telstar and Relay, were deployed, and thefirst geostationary satellite, called Syncom, was launched in 1963. The race forspace exploitation for commercial and civil purposes thus truly started.A satellite is geostationary if it remains relatively fixed (stationary) in anapparent position relative to the earth. This position is typically about35,784 km away from the earth. Its elevation angle is orthogonal (i.e., 90 )to the equator, and its period of revolution is synchronized with that of theearth in inertial space. A geostationary satellite has also been called ageosynchronous or synchronous orbit, or simply a geosatellite.The first series of commercial geostationary satellites (Intelsat andMolnya) was inaugurated in 1965. These satellites provided video (television)Copyright © 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 18: about my promise to my students, an
Page 22: 2.3 Coverage Area and Satellite Net
Page 26: 1Basic Principles of SatelliteCommu
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
Page 72: stable over their operating tempera
Page 76: 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
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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
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discriminate among carriers by temp
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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
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Copyright © 2002 by Marcel Dekker,
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5.2 CAPACITY COMPARISON OFMULTIPLE-
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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
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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
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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
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Frequency divisionmultiple accessFr
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MultiplexingNetworkOmnidirectionala
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UplinkUser-to-networkinterfaceThe e
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