Channel encoding and decoding method and apparatus

A to the communication system and remote unit is respectively code collecting to the data pulse train code, and a multiple access to the centre) and associated coded pulse data train method and device. When the central vertical from the remote unit for receiving data pulse train, the data pulse train and predetermined rate of centralized each code and centre and demodulation receive's pulse data train a receiving is related, which is suitable for determining with maximum relevance. The central vertical to obtain to by relevance number of the remote unit timing signal and/or the carrier frequency modulation signal. The signal to a remote unit and synchronization for transmitting the data the pulse train timing adjusting or for transmitting the data the pulse train carrier frequency information. The central station can also use the related estimate signal-to-noise ratio.