{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T06:34:27Z","timestamp":1762324467474,"version":"build-2065373602"},"reference-count":25,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2019,4,9]],"date-time":"2019-04-09T00:00:00Z","timestamp":1554768000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>In synthetic aperture radar (SAR) images, azimuth ambiguity is one of the important factors that affect image quality. Generally, the azimuth ambiguity-to-signal ratio (AASR) is a measure of the azimuth ambiguity of SAR images. For the low signal-to-noise ratio (SNR) ocean areas, it is difficult to accurately estimate the local AASR using traditional estimation algorithms. In order to solve this problem, a local AASR estimation method based on the Doppler power spectrum in SAR images is proposed in this paper by analyzing the composition of the local Doppler spectrum of SAR images. The method not only has higher estimation accuracy under low SNR, but also overcomes the limitations of traditional algorithms on SAR images when estimating AASR. The feasibility and accuracy of the proposed method are verified by simulation experiments and spaceborne SAR data.<\/jats:p>","DOI":"10.3390\/rs11070857","type":"journal-article","created":{"date-parts":[[2019,4,10]],"date-time":"2019-04-10T03:47:36Z","timestamp":1554868056000},"page":"857","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Local Azimuth Ambiguity-to-Signal Ratio Estimation Method Based on the Doppler Power Spectrum in SAR Images"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-3750-7561","authenticated-orcid":false,"given":"Hui","family":"Meng","sequence":"first","affiliation":[{"name":"National Key Lab of Microwave Imaging Technology, Beijing 100190, China"},{"name":"Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Electronics, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100190, China"}]},{"given":"Jinsong","family":"Chong","sequence":"additional","affiliation":[{"name":"National Key Lab of Microwave Imaging Technology, Beijing 100190, China"},{"name":"Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China"}]},{"given":"Yuhang","family":"Wang","sequence":"additional","affiliation":[{"name":"National Key Lab of Microwave Imaging Technology, Beijing 100190, China"},{"name":"Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Electronics, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100190, China"}]},{"given":"Yan","family":"Li","sequence":"additional","affiliation":[{"name":"National Key Lab of Microwave Imaging Technology, Beijing 100190, China"},{"name":"Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Electronics, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100190, China"}]},{"given":"Zhuofan","family":"Yan","sequence":"additional","affiliation":[{"name":"National Key Lab of Microwave Imaging Technology, Beijing 100190, China"},{"name":"Institute of Electronics, Chinese Academy of Sciences, Beijing 100190, China"},{"name":"School of Electronics, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100190, China"}]}],"member":"1968","published-online":{"date-parts":[[2019,4,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4038","DOI":"10.1109\/TGRS.2013.2279109","article-title":"Mitigation of azimuth ambiguities in spaceborne stripmap sar images using selective restoration","volume":"52","author":"Chen","year":"2014","journal-title":"IEEE Trans. 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