Multiple BPSK/LFM Hybrid Modulated Signals Parameter Estimation and Analysis Intercepted by Non-Cooperative Radar Receiver

The electromagnetic environment is becoming increasingly complex and the non-cooperative radar receiver will intercept the multiple concurrent radar signals. The binary phase shift keying/linear frequency modulated (BPSK/LFM) hybrid modulated signal is a novel kind of low probability of intercept (LPI) signal. In this paper, a new parameter estimation method is proposed for the multiple BPSK/LFM signals. The squaring process and fractional Fourier transform are used to estimate the chirp rate. Then, the output signal to interference plus noise ratio (SINR) is analyzed. Finally, the code rate estimation is given based on the linear transformation. Numerical simulation results show the efficacy of the proposed method and the correctness of the analysis.