Differential PSK block demodulation over a flat correlated Rayleigh-fading channel

A technique is proposed to design a block demodulator for differential phase shift keying (DPSK) signals over a frequency flat correlated Rayleigh-fading channel. The technique allows one to drastically reduce the error floor typically present in the bit error rate (BER) curves at high signal to noise ratios (SNRs). The main idea is to use the Karhunen-Loeve expansion to have a more precise description of the fading process at the receiver end.