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View File - University of Engineering and Technology, Taxila

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10. Kantor, L. Y. (ed). (1987). H<strong>and</strong>book <strong>of</strong> Satellite Communication <strong>and</strong> Broadcasting.Artech House.PROBLEMS1. Your boss named you as the system analyst to integrate the company’snew earth station in order to access an existing satellite network; forexample, INTELSAT or EUTELSAT. Describe the factors you willconsider to implement this task.2. An M-ary communication system transmits data at a rate <strong>of</strong> 10 4symbol=sec. Estimate the equivalent bit rates in bit=sec forM ¼ 4; 8; <strong>and</strong> 64.3. BPSK <strong>and</strong> QPSK systems are designed to transmit equal (1) rates; that is,two bits are transmitted with the BPSK system for each phase in theQPSK system, <strong>and</strong> (2) transmission b<strong>and</strong>widths. Compare the systems’symbol error probabilities versus energy per bit-to-noise power densityratio.4. An earth station received a digital signal from a satellite with an energyper bit-to-noise power density ratio <strong>of</strong> 20 dB.(a) If the required bit error rate is 10 5 , what is the maximum datatransmission rate possible with a PSK modulation?(b) For an available b<strong>and</strong>width <strong>of</strong> 100 Hz, compare your result with thecapacity <strong>of</strong> the system. What is the required energy per bit-to-noisepower density ratio at capacity?5. You will investigate digital communication from a geosynchronoussatellite to an earth station. The following parameters are given:Transmission power ¼ 9.5 W.Frequency ¼ 0.35 GHz.Antenna gains <strong>of</strong> the satellite <strong>and</strong> earth station are 10.05 <strong>and</strong> 29.75 dB,respectively,Additive noise spectral density is 10 20 W=Hz.Desirable error probability is 10 5 .(a) What is the maximum data rate the system will allow, assuming anideal PSK modulation?(b) Find the maximum binary rate for M ¼ 32.(c) The error probability must be extremely small. What is the maximumtransmission rate possible if an arbitrarily large b<strong>and</strong>width <strong>and</strong>complex encoding scheme are allowed?Copyright © 2002 by Marcel Dekker, Inc. All Rights Reserved.

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