SOVA Decoded Serially Concatenated Continuous Phase Modulations with Binary Markov Source

We investigate a method to utilize source memory information for a Soft-Output Viterbi algorithm (SOVA) decoded Serially Concatenated Continuous Phase Modulation (SCCPM) system. The system concatenates a recursive systematic convolutional (RSC) code with a binary full-response continuous phase modulation (CPM) signal. We apply the SOVA as the Soft-Input Soft-Output (SISO) decoder for both the CPM and RSC components. We modify the RSC SOVA decoder to combine the a priori information provided by the CPM SOVA decoder with the a priori information from a Markov source. Simulation results show that incorporating source statistics information improves the error performance of the SCCPM system and accelerates decoding convergence during iterative decoding.