Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data Focusing

In this study, we focus on the ultra-long integration of orbital perturbations of geosynchronous Synthetic Aperture Radar (SAR) for imaging. By deriving mathematical expressions for the Doppler rate and quadratic phase from orbital elements perturbated by oblateness or the J2 term of the non-spheric...

Full description

Bibliographic Details
Main Author: Hu Wenlong
Format: Article
Language:English
Published: China Science Publishing & Media Ltd. (CSPM) 2016-06-01
Series:Leida xuebao
Subjects:
Online Access:http://radars.ie.ac.cn/CN/html/R15121.htm
_version_ 1797428100575789056
author Hu Wenlong
author_facet Hu Wenlong
author_sort Hu Wenlong
collection DOAJ
description In this study, we focus on the ultra-long integration of orbital perturbations of geosynchronous Synthetic Aperture Radar (SAR) for imaging. By deriving mathematical expressions for the Doppler rate and quadratic phase from orbital elements perturbated by oblateness or the J2 term of the non-spherical gravitational force of the Earth, we analyze the impact on SAR data focusing. Based on our results, we conclude that the quadratic phase will exceed 45°, which is the defocusing threshold for imaging, after accumulation during a long integration time at the minute level. Because the potential for defocusing exists throughout nearly the entire satellite motion cycle, the SAR processor must carefully manage and compensate for the quadratic phase to avoid image degradations.
first_indexed 2024-03-09T08:53:13Z
format Article
id doaj.art-86309eb4a9454869a7ee3f8bc0de459b
institution Directory Open Access Journal
issn 2095-283X
2095-283X
language English
last_indexed 2024-03-09T08:53:13Z
publishDate 2016-06-01
publisher China Science Publishing & Media Ltd. (CSPM)
record_format Article
series Leida xuebao
spelling doaj.art-86309eb4a9454869a7ee3f8bc0de459b2023-12-02T13:41:43ZengChina Science Publishing & Media Ltd. (CSPM)Leida xuebao2095-283X2095-283X2016-06-015331231910.12000/JR15121Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data FocusingHu Wenlong0①(Institute of Electronics, Chinese Academy of Sicences, Beijing 100190, China) ②(Key Laboratory of Technology in GeoSpatial Information Processing and Application System, Chinese Academy of Sicences, Beijing 100190, China)In this study, we focus on the ultra-long integration of orbital perturbations of geosynchronous Synthetic Aperture Radar (SAR) for imaging. By deriving mathematical expressions for the Doppler rate and quadratic phase from orbital elements perturbated by oblateness or the J2 term of the non-spherical gravitational force of the Earth, we analyze the impact on SAR data focusing. Based on our results, we conclude that the quadratic phase will exceed 45°, which is the defocusing threshold for imaging, after accumulation during a long integration time at the minute level. Because the potential for defocusing exists throughout nearly the entire satellite motion cycle, the SAR processor must carefully manage and compensate for the quadratic phase to avoid image degradations.http://radars.ie.ac.cn/CN/html/R15121.htmGeosynchronous SAR (GEOSAR)Orbital perturbationSAR imaging
spellingShingle Hu Wenlong
Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data Focusing
Leida xuebao
Geosynchronous SAR (GEOSAR)
Orbital perturbation
SAR imaging
title Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data Focusing
title_full Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data Focusing
title_fullStr Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data Focusing
title_full_unstemmed Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data Focusing
title_short Impact of Earth’s Oblateness Perturbations on Geosynchronous SAR Data Focusing
title_sort impact of earth s oblateness perturbations on geosynchronous sar data focusing
topic Geosynchronous SAR (GEOSAR)
Orbital perturbation
SAR imaging
url http://radars.ie.ac.cn/CN/html/R15121.htm
work_keys_str_mv AT huwenlong impactofearthsoblatenessperturbationsongeosynchronoussardatafocusing