Optimal noncoherent detection of PSK signals

The optimal noncoherent sequential receiver for PSK signals, and some reduced complexity near-optimal decoder structures are derived. The performance of the optimal noncoherent receiver asymptotically approaches that of the coherent detector. The proposed suboptimal structures have performance close to the optimal receiver, but their complexity remains low. Evaluation of the new schemes for the pi /4-QPSK (the new North American standard for cellular mobile radio) and 8-PSK indicate improvements of up to 1.9 dB (at BER=10-4).