基于低轨卫星机会照射源的无人机目标前向散射探测方法与实验  

Methods and Experiments for Forward Scattering Detection of UAV Targets Based on Opportunistic Illumination from Low-Orbit Satellites

作　　者：周昕 易建新[1] 万显荣[1] 袁祎平 郝才勇 ZHOU Xin;YI Jianxin;WAN Xianrong;YUAN Yiping;HAO Caiyong(Electronic Information School,Wuhan University,Wuhan,Hubei 430072,China;Shenzhen Station of State Radio Monitoring Centre,Shenzhen,Guangdong 518000,China)

机构地区：[1]武汉大学电子信息学院,湖北武汉430072 [2]国家无线电监测中心深圳监测站,广东深圳518000

出　　处：《信号处理》2024年第12期2105-2115,共11页Journal of Signal Processing

基　　金：国家自然科学基金(61931015,62071335,62250024);湖北省自然科学基金创新群体(2021CFA002);中央高校自主研究项目(2042022dx0001)。

摘　　要：随着无人机技术的发展与普及,当下对无人机典型“低慢小”目标的高效监测需求逐渐凸显。针对无人机探测的难点,本文提出一种利用低轨卫星作为机会照射源的新式无人机低空探测方法,结合前向散射体制小型化、反隐身与卫星信号全天候、易获取的特点,深入研究了卫星信号前向散射雷达在无人机探测领域的潜在应用。首先,本文详细分析了卫星信号前向散射雷达的几何结构,介绍了前向散射雷达信号处理流程,构建了基于目标水平基线距离的雷达评估模型,仿真了不同目标飞行高度下雷达可探测的最大水平基线距离,仿真结果表明:无人机飞行高度对前向散射探测距离的影响较小,当无人机飞行高度为100 m时,雷达探测的最大水平基线距离为77.2 m;同时分析了卫星运动与天线波束对无人机目标时频特征的影响,分析结果表明,低轨卫星运动对时频特征影响较小;当天线波束过于狭窄时,时频响应由“V”形图像变为“竖条”图像。随后,针对低轨卫星高速运动的特点设计了一套低轨卫星信号接收系统,开展了系统测试实验,测试实验结果表明所设计系统能够稳定、实时地接收低轨卫星信号。最后,利用所设计的接收系统,开展了低轨卫星前向散射雷达无人机探测实验,获得了无人机穿越基线时的前向散射时频特征,实验结果与仿真结果相吻合,证明了理论分析的正确性以及所提体制探测无人机目标的可行性。Owing to advancements in unmanned aerial vehicle(UAV)technology,the demand for the efficient monitor‐ing of typical“low,slow,small”target UAVs has increased.Given the difficulties in UAV detection,this study pro‐posed a new type of UAV low-altitude detection method using low-orbit satellites as the source of opportunity illumina‐tion,combining the miniaturization of the forward scattering system,anti-stealth,and the all-weather and easy-to-acquire characteristics of satellite signals,and investigated the potential applications of the satellite signal forward scat‐tering radar for UAV detection.First,this study analyzed the geometric structure of the satellite signal forward scattering radar,introduced the signal processing flow of the forward scattering radar,constructed the radar evaluation model based on the horizontal baseline distance of the target,and simulated the maximum horizontal baseline distance that can be detected by the radar under the different target flight heights.The simulation result showed that when the flight alti‐tude of the UAV was 100 m,the maximum horizontal baseline distance detected by the radar was 77.2 m.Modeling analysis of the satellite motion and antenna beamform on the time-frequency characteristics of the UAV target was con‐ducted.The analysis results showed that the motion of LEO satellites had less influence on the time-frequency character‐istics;when the antenna beam was too narrow,the time-frequency response changed from a“V”-shaped image to a“vertical bar”image.A low-orbit satellite signal-receiving system was also designed according to the characteristics of high-speed movement of low-orbit satellites,and system test experiments were conducted,and the results of the test ex‐periments showed that the designed system received low-orbit satellite signals in a stable manner and in real time.Fi‐nally,the low-orbit satellite forward scattering radar UAV detection experiment was conducted,and the time-frequency characteristics of the forward scatterin

关 键 词：低轨卫星 前向散射雷达 星链 无人机探测 

分 类 号：TN95[电子电信—信号与信息处理]