基于二阶Keystone的微弱运动目标检测  

Weak Moving Target Detection Based on Second-Order Keystone Transform

作　　者：翟心蝶 杨刚 廉杰 ZHAI Xin-die;YANG Gang;LIAN Jie(Beijing Institute of Remote Sensing Equipment,Beijing 100854,China)

机构地区：[1]北京遥感设备研究所,北京100854

出　　处：《现代防御技术》2021年第3期105-114,共10页Modern Defence Technology

摘　　要：雷达技术是为了探测远距离目标而发展起来的。弹载雷达处理回波信号,实现对移动目标的测速与测距。微弱运动目标的“远距、低可探测、高机动”性使传统的检测方法难以识别、探测、跟踪。为提高对这类目标的检测能力,常会对信号进行积累。但由于目标的运动,长时间积累会产生跨越距离走动单元与跨速度单元现象。研究了匀加速运动目标回波信号模型,分析其中引起距离走动的分项,分析比较用一阶与二阶Keystone算法校正距离走动的效果,选择用CZT-IFFT(Chirp-Z transformation-inverse fast fourier transform)的方法实现二阶Keystone校正距离弯曲与距离走动,并对比了不同校正方法的信噪比改善效果。Radar technology was developed to detect distant targets.The missile-borne radar processes echo signals to achieve the speed measurement and ranging of moving targets.The“long distance,low observable and high speed maneuvering”of weak moving targets make it difficult for traditional detection methods to identify,detect and track them.In order to improve the detection ability of such targets,signals are often be integrated.However,due to the movement of the target,the across range unit effect and Doppler frequency migration effect will be produced in the long-time integration of signal.The echo model construction of rectilinearly moving targets with uniform velocity and acceleration is studied,and the items that cause the ARU(across range unit)effect are analyzed.To analyzed the effect of the range walk compensation,the simulation of first-order and second-order Keystone algorithm is compared.The CZT-IFFT(Chirp-Z transformation-inverse fast fourier transform)method is selected to realize the second-order Keystone algorithm,correcting the range curvature and range walking,and the signal-to-noise ratio gain of different correction methods are compared.

关 键 词：线性调频信号 距离走动 相参积累 二阶Keystone变换 信噪比增益 

分 类 号：TN957.51[电子电信—信号与信息处理] TN958.2[电子电信—信息与通信工程]