An Improved Altimeter in-Orbit Range Noise-Level Estimation Approach Based on Along-Track Differential Method

doi:10.3390/rs14246250

CORC > 海洋研究所 > 中国科学院海洋研究所 > 海洋环流与波动重点实验室

	An Improved Altimeter in-Orbit Range Noise-Level Estimation Approach Based on Along-Track Differential Method
	Liu, Xiaonan 2,3; Kong, Weiya 3; Sun, Hanwei 3; Xu, Yongsheng 1; Lu, Yaobing 3
刊名	REMOTE SENSING
	2022-12-01
卷号	14 期号:24 页码:19
关键词	altimeter in-orbit noise level along-track differential method power spectrum density analysis Sentinel-6 ocean swells
DOI	10.3390/rs14246250
通讯作者	Sun, Hanwei(sunhw12@tsinghua.org.cn)
英文摘要	Satellite radar altimeters are advanced remote sensing devices that play an important role in observing the global marine environment. Accurately estimating the noise level of altimeter in-orbit ranging data is crucial for evaluating the payload performance, analyzing sea conditions, and monitoring data quality. In this study, we propose an approach based on the differential processing of along-track odd-even data sequences for altimeter in-orbit range noise-level estimation. Using the long-term along-track data sequence can notably improve the issue in the existing method in that the noise level is underestimated owing to the utilization of a relatively short data segment. On the basis of an analysis of the influence of low-frequency components on noise-level estimation, the mathematical formulas of the above differential method were deduced, and the efficacy of the approach in assessing the noise level of altimeter in-orbit data was demonstrated by simulation experiments. This method was used to estimate the noise levels of the 20 Hz datasets of Jason-3 and Sentinel-6, and the idea of the time-domain difference was extended to the frequency domain. The statistical results showed that the 20 Hz noise levels at the significant wave height (SWH) = 2 m were 7.41 cm (Jason-3 low-resolution (LR) mode), 6.66 cm (Sentinel-6 LR mode), and 3.13 cm (Sentinel-6 high-resolution (HR) mode). The power spectrum density analysis further verified its accuracy. By reprocessing the 20 Hz data of Sentinel-6 into 10, 5, and 1 Hz, the effectiveness of the along-track odd-even differential method to directly evaluate the noise level of 1 Hz data was explored, and the impact of ocean signals such as swells on noise-level estimation in synthetic aperture mode was discussed.
资助项目	Science and Technology Innovation Project of LaoShan Laboratory ; National Natural Science Foundation of China[LSKJ202201301] ; [U22A20587]
WOS研究方向	Environmental Sciences & Ecology ; Geology ; Remote Sensing ; Imaging Science & Photographic Technology
语种	英语
出版者	MDPI
WOS记录号	WOS:000904522800001
内容类型	期刊论文
源URL	[http://ir.qdio.ac.cn/handle/337002/181399]
专题	海洋研究所_海洋环流与波动重点实验室
通讯作者	Sun, Hanwei
作者单位	1.Chinese Acad Sci, Inst Oceanol, Lab Ocean & Climate Dynam, Qingdao 266071, Peoples R China 2.Second Acad China Aerosp, Grad Sch, Beijing 100854, Peoples R China 3.Beijing Inst Radio Measurement, Beijing 100854, Peoples R China
推荐引用方式 GB/T 7714	Liu, Xiaonan,Kong, Weiya,Sun, Hanwei,et al. An Improved Altimeter in-Orbit Range Noise-Level Estimation Approach Based on Along-Track Differential Method[J]. REMOTE SENSING,2022,14(24):19.
APA	Liu, Xiaonan,Kong, Weiya,Sun, Hanwei,Xu, Yongsheng,&Lu, Yaobing.(2022).An Improved Altimeter in-Orbit Range Noise-Level Estimation Approach Based on Along-Track Differential Method.REMOTE SENSING,14(24),19.
MLA	Liu, Xiaonan,et al."An Improved Altimeter in-Orbit Range Noise-Level Estimation Approach Based on Along-Track Differential Method".REMOTE SENSING 14.24(2022):19.