Noncoherent Reduced State Differential Sequence Detection of Continuous Phase Modulation
连续相位调制的非相干减少状态差分序列检测算法

A noncoherent Reduced State Differential Sequence Detection (RSDSD) for Continuous Phase Modulation (CPM) is proposed in this paper. The algorithm makes use of the reduced state trellis based on Reduced State Sequence Detection (RSSD) and performs one-symbol differential Viterbi detection. The minimum square Euclidean distance of the reduced state trellis is analyzed for full response CPM and partial response CPM. Performance of RSSD and RSDSD is simulated for octal 2RC signal with h=1/8 in the AWGN channel and comparisons are made between different reduction schemes and between coherent RSSD and noncoherent RSDSD with Doppler frequency shifts. Simulation results show: although the proposed algorithm is degraded by 2dB at 10-3 bit error rate compared with coherent Maximum Likelihood Sequence Detection(MLSD), it is more appropriate and robust to the situation when the carrier recovery is difficult.