原始数据压缩对简缩极化SAR极化信息的影响  

Effect of raw data compression on polarimetric information of compact polarimetric SAR

作　　者：谭洪[1,2,3] 洪峻[2,3] 仇晓兰[1,2] 

机构地区：[1]中国科学院空间信息处理与应用系统技术重点实验室,北京100190 [2]中国科学院电子学研究所,北京100190 [3]中国科学院大学电子电气与通信工程学院,北京100049

出　　处：《系统工程与电子技术》2016年第8期1780-1786,共7页Systems Engineering and Electronics

基　　金：国家自然科学基金(61331017)资助课题

摘　　要：简缩极化(compact polarimetric,CP)合成孔径雷达(synthetic aperture radar,SAR)是近年发展起来的一种特殊极化SAR,为了降低原始数据率,需要进行数据压缩,压缩误差将影响数据的极化信息。利用仿真数据,在不同信杂比下研究了当前普遍使用的4bit截取、8∶3分块自适应量化(block adaptive quantization,BAQ)和8∶4BAQ3种压缩方法引入的极化失真,并比较了简缩极化SAR不同工作模式对压缩噪声的敏感性。定义了一个指标以评价简缩极化SAR数据的极化精度。仿真结果表明,在信杂比远高于40dB时8∶4BAQ性能最佳,8∶3BAQ性能最差,其他信杂比下3种压缩方法性能趋于一致,而π/4模式对压缩噪声的敏感性最强。Compact polarimetric（CP）synthetic aperture radar（SAR）is a recently developed special SAR system.In order to reduce the raw data rate,a data compression has to be performed,and the polarimetric information of SAR measurement will be deteriorated by compression errors.Three widely-used raw data compression methods,including 4bit quantization,8∶3block adaptive quantization（BAQ）and 8∶4BAQ,are evaluated through simulated data under different signal-to-clutter ratio（SCR）conditions.The sensitivities of different CP SAR working modes to data compression noises are analyzed.A metric is defined to measure the polarization quality of CP SAR data.Simulation results show that the 8∶4BAQ performs the best and the 8∶3BAQ performs the worst on condition that the SCR is much higher than 40 dB,and that the three compression methods have similar performances on condition of SCR that is lower than 40 dB.The sensitivity of theπ/4mode to data compression noises is larger than that of both the CTLR mode and the DCP mode.

关 键 词：合成孔径雷达 简缩极化 原始数据压缩 极化信息 极化失真 

分 类 号：TN958[电子电信—信号与信息处理]