Error rate analysis of DCPSK over generalized fading channels

Binary and quaternary -differential coherent phase-shift keying (DBPSK, DQPSK) are widely used modulations in digital wireless systems. However, a simple expression for the probability density function (pdf) of the decision statistic and the error rate performance of such systems under post-detection equal gain combining (KGC) and generalized fading channels are not currently available in the literature. This paper presents a discussion of these subjects in detail. Our analytic study is based on a convergent infinite series for the sum of independent random variables that has been derived using Fourier series approximation method. Generalized fading channels including Rayleigh, Ricean, and Nakagami-m are investigated. The channels are assumed to be independent, frequency-nonselective, and slowly varying. The accuracy of our results is verified through simulation.