Non-uniform phase filter for Tiangong-2 Interferometric Imaging Radar Altimeter

The Journal of Engineering

Yunhua Zhang¹  Xiao Dong¹ 

[1] National Space Science Center;

关键词: radar interferometry;    radar altimetry;    radar imaging;    topography (Earth);    digital elevation models;    oceanographic techniques;    remote sensing by radar;    synthetic aperture radar;    nonuniform windows;    Tiangong-2 InIRA data;    nonuniform filtering method;    nonuniform phase filter;    Tiangong-2 interferometric imaging radar altimeter;    Chinese Tiangong-2 space laboratory;    wide-swath ocean topography;    traditional interferometric synthetic aperture radar;    digital elevation model;    land surface;    ocean surface;    interferometric phase noise;    ocean height measurements;    traditional InSAR;    height error;    interferometric imaging radar altimeter;    Ku-band interferometric radar;   

DOI  :  10.1049/joe.2019.0430

来源: DOAJ

【 摘 要 】

The interferometric imaging radar altimeter (InIRA) on-board Chinese Tiangong-2 space laboratory is a Ku-band interferometric radar whose major aim is to measure the wide-swath ocean topography. Unlike traditional interferometric synthetic aperture radar (InSAR) aiming at measuring digital elevation model of land surface, Tiangong-2 InIRA adopts small incidence angles and short baseline to get strong and high coherency reflections from ocean surface. The interferometric phase noise is a notable source of errors which limits the accuracy of the ocean height measurements. Compared with traditional InSAR, the height error of Tiangong-2 InIRA shows different distribution pattern due to the absolutely small but relatively large variation incidence angles. This study gives a filtering method for interferometric phase generated with small incidence angles and short baseline. Non-uniform windows are selected according to the relation between the coherence, imaging geometry, and the height variation. Results on Tiangong-2 InIRA data are analysed by comparing the non-uniform filtering method with traditional multi-looking method.

【 授权许可】

Unknown