星机双基SAR波束空间同步误差及性能分析  

Beam space synchronization error and performance analysis of spaceborne-airborne bistatic SAR

作　　者：张博丰 李雯雯 刘霖 ZHANG Bofeng;LI Wenwen;LIU Lin(Aerospace Information Research Institute,Chinese Academy of Sciences,Beijing 100094,China;School of Electronic,Electrical and Communication Engineering,University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院空天信息创新研究院,北京100094 [2]中国科学院大学电子电气与通信工程学院,北京100049

出　　处：《电子设计工程》2024年第15期50-55,60,共7页Electronic Design Engineering

摘　　要：星机双基合成孔径雷达(SA-BiSAR)系统利用卫星作为发射站,飞机作为接收站,利用收发分置的特点可以有效提高系统抗干扰能力。为满足成像需求,收发基站的雷达波束指向需满足严格的空间同步要求,必须在成像之前进行波束空间同步检测。针对波束同步检测这一问题,文中建立了星机双基SAR波束同步的数学模型,引入收发波束重叠比反映收发波束的相对关系,通过系统接收信噪比定量分析了无误差情况、飞机存在定位误差和指向误差情况下的系统性能。在飞机斜距为85.6 km的仿真条件下,仿真结果表明,文中建立的数学模型以及信噪比分析方法可有效反映收发波束相对关系及同步性能;当同时存在-5 km定位误差以及0.2°指向误差时,系统性能与无误差时相比整体下降了1 dB以上,中心区域范围较原来大幅缩小,波束中心区域边界点与无误差时位置差达8 km以上。The Spaceborne-Airborne Bistatic Synthetic Aperture Radar(SA-BiSAR)system uses the satellite as the transmitting station and the aircraft as the receiving station,which can effectively improve the anti-jamming ability of the system.To meet the imaging requirements,the radar beam pointing at the transceiver needs to satisfy strict spatial synchronization requirements,and the spatial synchronization detection of the beam must be performed before imaging.Aiming at beam synchronization detection,this paper established a mathematical model of beam synchronization in spaceborne-airborne bistatic SAR,and introduced the overlap ratio of transmitting and receiving beams to reflect the relative relationship between transmitting and receiving beams.The system performance was quantitatively analyzed by the received Signal-to-Noise Ratio(SNR)in the case of no error,positioning error,and pointing error of aircraft.Under the simulation condition that the aircraft slant range is 85.6 km,the simulation results show that the mathematical model and the Signal-to-Noise Ratio analysis method established in this paper can effectively reflect the beam relative relationship between transmitting and receiving beams and synchronization performance.When the positioning error and pointing error are-5 km and 0.2°,respectively,the system performance is decreased by more than 1 dB compared with the errorless case,the range of the center region is greatly reduced,and the position difference of the boundary points in the beam center region exceeds 8 km.

关 键 词：星机双基SAR 波束空间同步 误差分析 波束相对关系 

分 类 号：TN95[电子电信—信号与信息处理]