基于重叠滑窗时频分析的跳频信号检测技术

Detection of Short-Wave Frequency Hopping Signal Based on Overlapped-Sliding Time-Frequency Analysis

针对复杂短波环境下跳频信号检测与分离难度大的情况,提出一种基于滑窗重叠时频分析的跳频信号检测技术。该技术利用时间窗重叠的短时傅里叶变换,获取同时具备较高频率分辨率和时间分辨率的信号二维时频谱,提高信号检测概率;同时,通过信号状态判决与基于状态的参数融合修正机制,有效提高跳频信号时频参数测量精度;经时频参数过滤分析,准确实现复杂环境下跳频信号分量的提取分离。

Aiming at the difficulty of detection and separation of frequency-hopping signals in complex shortwave electromagnetic environment, a new signal detection technology based on time-frequency analysis with overlapping sliding window is proposed. An improved short-time Fourier transform is proposed to obtain 2-D time-frequency spectrum with both high frequency resolution and time resolution, which improves the detection probability of signals. Then, time and frequency parameters are estimated precisely by signal state judgment and parameter fusion correction mechanism based on state. Finally, frequency-hopping signals are extracted correctly by time-frequency parameters’ filter in complex electromagnetic environment.