8APSK_TCM Coding Method Application in Underwater Acoustic Communication

The TCM coding method applied in underwater acoustic communication system was studied.The main factors which affected its performance were analyzed, that were the effective code length and minimum product distance.The method of designing asymmetric modulation─8APSK_TCM based on the underwater acoustic channel was proposed,and the performance of it wassimulated in the Acoustic channel model.Simulation shows that the 8APSK_TCM scheme can bring a coding gain more than the normal scheme.This will improve the performance of underwater acoustic communication.