The detection methods of DSSS/QPSK signal based on the fourth-order moment

An accumulation detection method based on the fourth-order moment m4x (0,0,τ) in time domain for the DSSS signal is proposed. Experimental results show that the detection performance of the accumulation method is better than that of the non-accumulation method. It can effectively detect the DSSS signal modulated by QPSK at SNR -16dB. The computation complexity of the method is low and it is easy to implement.