M-algorithm decoding of convolutional code combined with CPM

The performance of convolutional codes combined with continuous phase modulation schemes (CC/CPM) with M-algorithm decoding is evaluated by computer simulation. New CC/CPM schemes with a feedback convolutional encoder having, in some cases, better distances than previous CC/CPM which uses a feedforward encoder, are presented. Comparison of CC/CPM and CPM, constrained to the same complexity and bandwidth, shows that the former have a better performance. The simulation results also corroborate the fact that the M-algorithm is far more efficient than the Viterbi algorithm