This Letter presents an adaptive detection algorithm based on dynamic dual-threshold for low probability of intercept (LPI) radar signals in complex electromagnetic environments. The algorithm dynamically estimates background noise to effectively suppress interference spikes and prevent signal splitting. Experimental results demonstrate: detection probability reaches 82.6% at 0 dB SNR, improving 14.1% over CA-CFAR; false alarm rate deviation remains within 12%; FPGA resource utilization below 0.7% with 1.2 μs processing latency; detection accuracy exceeds 93% for CW, BPSK, and LFM signals at SNR≥6dB. The algorithm provides an efficient and reliable solution for LPI radar signal detection.

With the increasing innovation of network communication technology, short burst communication has been developed to a certain extent in the time compression technology, which brings great challenges to the radio signal blind reception technology .In the blind reception of non-cooperative signals in short-time burst communication, signal time domain detection is the premise and key of signal modulation parameter estimation, signal demodulation, decoding, interpretation, information acquisition and interference guidance. In this paper, the blind demodulation method of short-time burst FM-MFSK signal is studied under the condition of low signal-to-noise ratio. A short-time burst FM-MFSK blind demodulation method based on STFT is proposed. When SNR is higher than 2dB, the correct demodulation probability for FM-MFSK signal can reach 90%.