Autocorrelation based modulation recognition of PSK signals for OFDM in underwater acoustics communication

Orthogonal frequency division multiplexing (OFDM) is a kind of high spectrum efficiency and ability to resist multipath fading of multi-carrier modulation technology, that is widely used in communication, and one of the core technology of the fourth generation of mobile communication. The purpose of underwater communication pattern recognition, is to recognize the modulation pattern from the received underwater acoustic communication signal. This technique has great influence on underwater acoustic communication interference spectrum monitoring, signal receiving and acknowledgment, communication management. In this paper, we have studied the method of cyclic cumulants and autocorrelation characteristics for OFDM signal modulation recognition and detected the signal in multipath condition. The results showed that autocorrelation characteristics still a best approach for recognizing the OFDM modulated signal.