基于改进椭圆模型的双站斜飞SAR成像算法  

An imaging algorithm for nonparallel-track bistatic SAR based on improved ellipse model

作　　者：丁颖铖 曹佳熠 谢君亮 钟华[1] DING Yingcheng;CAO Jiayi;XIE Junliang;ZHONG Hua(School of Communication Engineering,Hangzhou Dianzi University,Hangzhou Zhejiang 310018,China)

机构地区：[1]杭州电子科技大学通信工程学院,浙江杭州310018

出　　处：《杭州电子科技大学学报（自然科学版）》2022年第3期43-49,共7页Journal of Hangzhou Dianzi University：Natural Sciences

基　　金：浙江省公益技术研究计划资助项目(LGG18F010009);声纳技术重点实验室开放基金资助项目(6142109KF201807)。

摘　　要：在高分辨率机载双站斜飞模式合成孔径雷达(Bistatic Synthetic Aperture Radar,BiSAR)成像处理中,收发波束的不同步导致成像性能急剧下降。为此,提出一种基于改进椭圆模型的双站斜飞合成孔径雷达(Synthetic Aperture Radar,SAR)成像算法。首先,通过调整SAR成像几何构型,实现了收发波束的同步;然后,构建了改进椭圆模型,并重新推导扩展的非线性变标(Extended Non-Linear Chirp Scaling,ENLCS)算法,提升了双站斜飞SAR的成像效果。仿真实验表明,在距离向与方位向宽度均为2 km的场景下,改进算法的峰值旁瓣比(Peak Side Lobe Ratio,PSLR)和积分旁瓣比(Integration Side Lobe Ratio,ISLR)分别为-13.25 dB和-9.91 dB,接近成像性能指标的理论值,提升了成像效果。In the imaging processing of nonparallel-track bistatic synthetic aperture radar(BiSAR),the imaging quality declines sharply as the unsynchronization of the transmit-receive beams.Therefore,an imaging algorithm of nonparallel-track BiSAR based on improved elliptic model is proposed.Firstly,the SAR imaging geometry is adjusted to realize the synchronization of transmit-receive beams;Then,the improved ellipse model is constructed and the extended non-linear chirp scaling(ENLCS)algorithm is deduced again,which improves the imaging effect of nonparallel-track BiSAR.The simulation results show that in the scene with a range and azimuth width of 2 km,the peak side lobe ratio(PSLR)and integration side lobe ratio(ISLR)of the improved algorithm are -13.25 dB and -9.91 dB,respectively,which are close to the theoretical value of the imaging performance and improve the imaging effect.

关 键 词：合成孔径雷达 改进椭圆模型 非线性变标 

分 类 号：TN958.4[电子电信—信号与信息处理]