Multiple-symbol differential detection of DQPSK and DPSK mobile communication systems impaired by oscillator phase noise

A multiple-symbol differential detection (MSDD) scheme is proposed for the detection of binary differential-phase-shift-keying (DPSK) and DQPSK signals in the presence of additive white Gaussian noise (AWGN) and weak oscillator phase noise. An algorithm that is computationally more efficient than that suggested by the maximum-likelihood sequence estimation (MLSE), and referred to as CE-MSDD, is proposed. The performance of the CE-MSDD receiver is assessed in terms of symbol or bit error rate (BER) for various levels of full-width-at-half-maximum (FWHM) linewidth of the noisy oscillator using the Monte-Carlo (MC) simulation technique. The simulation results clearly underscore the superiority of the proposed schemes over their 2-symbol counterparts in the presence of phase noise.