/spl pi//4-DQPSK on microcellular radio channels with diversity and interference

A analyze the average bit error rate (BER) performance of /spl pi//4-shifted differential quadrature phase shift keying (/spl pi//4-DQPSK) in the presence of multiple independent cochannel interferers in frequency-nonselective fading environments. Nyquist shaped pulses are used and postdetection diversity combining is employed at the receiver. The use of both L-branch postdetection equal gain combining (EGC) and L-branch postdetection selection combining (SC) are considered. Two approaches for representing the cochannel interference are investigated. These are a Gaussian interference model and a synchronous interference model. The accuracies of both of these models are assessed by comparing their BER performances with precise BER results. The precise BER results are obtained by using a combination of analysis and simulation.<
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