Detection of DS/BPSK signal based on moving filtering algorithm in frequency domain under low SNR

A method is presented to detect DS/BPSK signal under low SNR. The existence of the signal can be judged according to the power magnitude on the carrier frequency of signals from correlator output. The detection principle is analyzed and the engineering achievement is introduced. To solve the effect of carrier frequency estimation errors, moving filtering in the frequency domain is given to calculate the signal power on the carrier frequency. Finally, simulation results are described to verify the method. The small signal can be rapidly detected through the computer or DSP because the method can be achieved by the software. The small signal is regarded as a mark signal to be linearly added into the communication signal to recognize some attributes of communication signals.