摘要
深空目标的雷达回波信号较弱而且受噪声干扰严重,给检测识别工作带来很大的困难;提出了一种时频滤波方法,将基于广义S变换的时频滤波引入到雷达回波信号去噪当中;采用广义S变换对回波信号进行时频分析,利用变换结果求解信号的瞬时频率,并构造了一种时频滤波器.对雷达回波信号进行时频滤波处理并对滤波效果进行分析;仿真结果表明,经滤波后信噪比有较大提高,且很好保留了信号特征。
The radar echo signal of targets in space is weak and interfered by noise seriously so it is difficult to detect and recognize them. An algorithm of time-frequency filter has been presented and a new method of time-frequency filter based on generalized S-transform has been introduced to radar signal processing.Introduced the rationale of S-transform and generalized S-transform and calculation method of instantaneous frequency.Constructed a kind of time-frequency filter and applied to the radar echo signal with noise.Analysis of filtering performance was presented.Simulation result showed that the method has good performance in improving signal-to-noise ratio meanwhile preserving the features of effective signal.
引文
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