A low SNR spectrum-correlated detect method of PCM-FM signal in high dynamic situation

Abstract

Considering Pulse Code Modulation-Frequency Modulation (PCM-FM) signal detect in high dynamic and low Signalto- Noise Ratio(SNR) situation，a low SNR spectrum-correlated detect method that is not sensitive to high dynamic situation is proposed. Firstly, this method uses the power spectrum of the known PCM-FM signal to match the power spectrum of the receiving signal, searches for the maximum filter output within the doppler frequency range, and constructs the detect statistics. Then, this method uses the probability of false alarm to compute detect threshold, and compares with the detect statistics to determine whether PCM-FM signal exists. The simulation result shows that the proposed method can detect PCM-FM signal quickly with high probability in high dynamic and low SNR situation.