The MPSK and MQAM signal modulation recognition algorithm in the multipath channel

摘要

This paper proposes a new Lempel-Ziv complexity feature recognition algorithm based on the nth-powered (n = 2) spectrum to deal with modulation recognition problem regarding MPSK and MQAM signals in multipath channels. Based on differences in the nth-powered (n = 2) spectrum amplitude value of MPSK and MQAM signals, the waveform characteristics of the multiplied spectrum are extracted in the multipath environment, and a total of five characteristic parameters are defined to distinguish the signals from the set {BPSK,OQPSK,QPSK,8PSK,PI/4DQPSK,16QAM,32QAM}. The simulation results show that the recognition algorithm performs well when recognising signals in a multipath situation and is less affected by the frequency deviation and shaping filter coefficient; therefore, it is very robust.