Performance of differentially detected pi /4-shifted DQPSK with diversity

The application of postdetection selection combining diversity in land mobile radio systems is addressed. Selection of an antenna-receiver pair is based on metrics that are functions of the signal-to-impairment power ratio at the outputs of differential detectors. That is, postdetection selection metrics are used. Because these schemes operate on the detector output, they can be used with hard-limited IF signals. The schemes are evaluated using the North American digital cellular channel structure and modulation. Simulation results are reported which show performance improvements in the presence of cochannel interference, multipath, and Doppler.<
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