基于脉内步进LFM时频分析的抗间歇采样干扰方法

在深入研究抗间歇采样干扰的基础上，针对其时域不连续转发与时域不连续采样两个特点，提出一种基于脉内步进线性调频（LFM）时频分析的抗间歇采样干扰方法.该方法利用脉内步进LFM子脉冲之间的正交性互相掩护，通过短时傅里叶变换，将时频矩阵在时间维投影，提取干扰不连续转发段信号，并以该段信号最大值为门限，对时频矩阵进行干扰抑制，抑制后时频矩阵通过逆短时傅里叶变换，得到时域信号，并用于目标检测.理论推导和仿真结果表明，该方法可以有效抑制不同样式的间歇采样干扰，最大限度提取不受干扰信号. 

Anti-Intermittent Sampling Repeater Jamming Method Based on Stepped LFM Joint Time-Frequency Analysis

Analyzing the principles of the ISRJ and the characteristics of the discontinuous retransmission and sampling of ISRJ in time domain, an anti ISRJ method based on stepped LFM joint time-frequency analysis (JTFA) was proposed. This method was designed to utilize the sub pulses'' orthogonality to cover each other, to extract the discontinuous retransmission signal segment with short time Fourier (STFT) in time domain, and taking the maximum signal of this segment as threshold to process the interferences suppression in time-frequency matrix. Through inverse STFT, the time domain signal could be obtained for target detection. Theoretical analysis and experimental results show this method can carry out anti ISRJ with different patterns, maximize the undisturbed signal.