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

摘要

The higher order statistics theory is used to study on the detection of the DSSS signal. The detection methods based on the fourth-order moment m{sub}(4x) (0,0, τ) in time domain and in frequency domain for the DSSS signal modulated by QPSK are proposed. The accumulation technology is applied to further improve the detection performance. Simulations results show that the detection performance of the method in frequency domain is better than that of the method in time domain, and the detection performance of the method with accumulation is better than that of the method without accumulation. The method with accumulation in frequency domain is the best one, and its detection probability for the DSSS signal modulated by QPSK is above 93% at SNR-24dB.