A new recognition method for phase-shift keying signals
Liping Liu · Harbin Gongcheng Daxue Xuebao/Journal of Harbin Engineering University · 2009
A new phase-shift keying(PSK) signal recognition method was developed for low signal to noise ratio(SNR) environments,and it significantly decreases the calculations required in PSK signal recognition compared to existing methods.It first estimates the power spectrum of received signals and smoothes the results.Then it breaks the peaks of signal strength of the power spectrum into 3 dB slices in order to estimate carrier frequency.The received signal is down converted to the baseband using this estimated value.Finally,by considering the amplitudes of cumulative outputs of the baseband signal's imaginary parts and real parts to be complementary,and its inflexion point to be just a jump point in its phase,the PSK signal can be identified.This method is easy to calculate and implement,and can be applied in low SNR situations.Simulations showed the validity of the algorithm.