A simple multi-symbol detector for CPM signals

It is known that multi-symbol detection shows good bit error rate performance for estimation of continuous phase modulation (CPM) signals, yet the complexity of its receiver structures goes exponentially with the increasing length of the pulse-shaping filter and observation window length. A new simple non-coherent trellis receiver for CPM signals is proposed in this paper. Similar to the simple coherent detectors, where CPM signals are approximately represented by a sum of Phase Amplitude Modulation (PAM) waveforms, Laurent decomposition is applied to reduce the complexity. The proposed receiver is structured with a much smaller number of matched filters in the front-end and a processor which uses Viterbi algorithm with a 2^N-1 states trellis to demodulate the receive signal. The good error performance is confirmed by simulation results.