Question

4.9. A system using matched filter detection of cqually likely BPSK signals, s(t) V2E Tcos o rand s2(1)-V2 E/T cos (oo t + π), operates in AwGN with a received E,N, of 6.8 dB. Assume that E{z(T) = ± VE (a) Find the minimum probability of bit error, PB, for this signal set and E,/No (b) If the decision threshold is γ= 0.1 VE, find PB. (c) The threshold of γ = 0.1 VE is optimum for a particular set of a priori probabili- ties, P (s,) and P(s2). Find the values of these probabilities (refer to Section B.2)

Answer 1

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