基于Gabor变换的对星载合成孔径雷达电子侦察信号的检测和特征分析研究

Signal detection and Features analysis in Electronic warfare against space-borne SAR based on Gabor representation

随着星载合成孔径雷达各种性能的不断提高,以常规参数测量作为特征的信号识别技术很难满足电子侦察的需求,基于雷达信号的脉内细微特征分析技术已经成为当前电子侦察的重要发展方向。为了提高在低信噪比条件下对雷达脉冲信号的检测概率和参数估计能力,本文使用了直接采样信号的Gabor变换进行信号检测和特征分析。Gabor变换是按照信号的先验知识选择合适的基函数,获得只有少数几个系数的Gabor展开,从而能够对信号作比较精确的表示。通过使用Gabor系数做检测统计量做噪声背景下的信号检测,可以得到雷达时域的常规参数。信号检测后得到的信号Gabor变换可以对信号的脉内细微特征进行分析。通过对脉内细微特征的分析可以获得敌方合成孔径雷达的技术参数,从而对它的用途和工作模式进行有效的推测。为了验证算法的有效性,本文进行了实测数据的分析实验。通过实验,本文使用的分析方法可以有效地用于雷达侦察信号检测和脉内细微特征分析,可以为后续处理提供有力的技术信息支撑。

With the improving capability of the space-borne SAR systems,signal identification using conventional parameter measurement techniques is difficult to satisfy the demand of Electronic Intelligence systems.Intrapulse minute features analysis of pulse signals have already become an important trend of electronic intelligence development.In order to improve the parameter precision and the detection probability of radar pulse signal in the condition of a low SNR,a Gabor representation detection and analysis algorithm is put forward.It can be used to detect the radar pulse signal and estimate its parameter.The Gabor representation of SAR signal can be computed for a given synthesis window,such as Gaussian window.Then,Intrapulse minute features analysis can be achieved using Gabor representation of SAR pulse signal.Because of the Intrapulse minute features analysis,we can acquire the parameter of the enemy＇ s radar system accurately,and can deduce the purpose of the SAR effectively.In order to prove the effectiveness of the arithmetic,a lot of experiments have been done for validating the arithmetic.The experiments show that the arithmetic is effective and the result can provide precious technology information for the next processing.