BER Performance of Coherent PSK in Rayleigh Fading Channel with Imperfect Phase Estimation

In this paper average bit error rate (BER) of coherent phase shift keying (PSK) modulations with improper phase estimation have been derived. A simple slow flat wireless fading channel obeying Rayleigh distribution is assumed for channel modelling. In addition the channel is also perturbed by additive white Gaussian noise (AWGN). The phase distortions considered in the paper are random, unbiased, i. e. having zero-mean and follows a Gaussian distribution. Analytical BER is calculated for the first two members of the PSK family, namely binary PSK (BPSK) and quaternary PSK (QPSK), through Hermite´s method of integration. Extensive Monte Carlo simulations were also performed to validate the theoretical results. In order to demonstrate the advantages of modulation schemes that do not require phase synchronization, BER performances of BPSK and QPSK with phase error are compared with the corresponding differential PSK modulations (DPSK and DQPSK respectively) of same constellation size.