摘要
为了利用星载global navigation satellite system-reflections(GNSS-R)的延迟-多普勒图(delay-doppler map,DDM)实现对海面目标位置的遥感探测,依据星载DDM的生成原理,研究实现了其反过程即从DDM中重构散射区域图像进而达到探测海面目标的目的。首先利用截断奇异值分解(truncated singular value decomposition,TSVD)法去除DDM中的模糊函数;然后通过计算归一化雷达横截面积(normalized radar cross-section,NRCS)重构海面散射区域图像。以2016年3月1日TechDemoSat-1(TDS-1)实测的DDM数据为例,首先计算了镜反射点(specular point,SP)的位置,然后进行重构实验。实验结果表明:计算得到的SP与TDS-1提供的SP之间的最大误差在800 m左右,小于TDS-1 5 km的距离分辨率;同时,重构图像中目标的位置与极地海冰数据中海冰的位置相吻合,由此可见本文的目标探测算法能够从DDM中探测到海面目标。
In order to detect the position of sea surface target remotely using delay-Doppler map（ DDM） of global navigation satellite system-reflections（ GNSS-R）,the research realizes the reverse process of reconstructing the scattering area image from the DDM according to the theory of generating air-borne DDM. Firstly the truncated singular value decomposition（ TSVD） method is adopted to eliminate the ambiguity function in DDM. Then the sea surface scattering area image is reconstructed by calculating normalized radar cross-section（ NRCS）. The TechDemo Sat-1（ TDS-1） satellitic DDM data on March 1,2016 were used as a cases for experiments,the position of specular point（ SP） is calculated first and then the reconstruction experiment is organized. The experimental results show as follow： the maximum errors between the SP calculated and the SP given by TDS-1 mission are about800 m,it is less than 5 km distance resolution of TDS-1; what＇s more,the location of the target area in the reconstructed sea image is basically consistent with the sea ice in Polar sea ice data,so the algorithm introduced can detect sea targets from DDM.
作者
刘池莉
严颂华
陈泽强
卜方玲
LIU Chi-li;YAN Song-hua;CHEN Ze-qiang;BU Fang-ling(Electonic Information School,Wuhan University1,Wuhan 430072,China;State Key Laboratory of Information Exgineering in Surveying,Mapping and Remote Sensing2,Wuhan University,Wuhan 430079,China)
出处
《科学技术与工程》
北大核心
2018年第17期250-256,共7页
Science Technology and Engineering
基金
国家自然科学基金(41571420)
中央高校基本科研业务费专项资金(2042017kf0211)
测绘遥感信息工程国家重点实验室专项科研经费资助
关键词
DDM
海面目标探测
GNSS-R
奇异值分解
delay-doppler map
ocean surface target detection
global navigation satellite system-reflec-tions
singular value decomposition
