{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,23]],"date-time":"2025-12-23T10:02:23Z","timestamp":1766484143822,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2020,10,27]],"date-time":"2020-10-27T00:00:00Z","timestamp":1603756800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Equipment Pre-research Foundation of China","award":["JZX7Y20190253040501, JZX7Y20190253041401 and JZX7Y20190253040901"],"award-info":[{"award-number":["JZX7Y20190253040501, JZX7Y20190253041401 and JZX7Y20190253040901"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61761037, 61631011 and 61701264"],"award-info":[{"award-number":["61761037, 61631011 and 61701264"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Key Laboratory Foundation","award":["6142216190209"],"award-info":[{"award-number":["6142216190209"]}]},{"DOI":"10.13039\/501100004763","name":"Inner Mongolia Natural Science Foundation","doi-asserted-by":"publisher","award":["2020ZD018"],"award-info":[{"award-number":["2020ZD018"]}],"id":[{"id":"10.13039\/501100004763","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>A synthetic aperture radar (SAR) system can be seriously contaminated by radio frequency systems because of working in the same microwave frequency bands, which would degrade the SAR image quality and affect the accuracy of image interpretation. In this paper, a novel radio frequency interference (RFI) suppression approach including RFI identification, band-stop filtering and a removed spectrum iterative adaptive approach (RSIAA) is proposed. First, the smoothing process is added before RFI signal detection to improve the RFI detection capacity. Afterwards, the band-stop filtering with a broaden factor is proposed to mitigate the residual RFI, and it ensures the accuracy of the following removed spectrum recovery by the RSIAA. Finally, the removed spectrum components are estimated from available adjacent spectrum data by the RSIAA in turn to obtain the desired range spectra. Compared with the conventional range frequency filtering method for RFI suppression, the capacity of the weak RFI signal detection is improved, and the increased sidelobes due to the discontinuous spectra are well suppressed. Simulation experiments on both simulated SAR raw data, Gaofen-3 and Sentinel-1 SAR raw data validate the proposed RFI suppression approach.<\/jats:p>","DOI":"10.3390\/rs12213520","type":"journal-article","created":{"date-parts":[[2020,10,27]],"date-time":"2020-10-27T09:22:45Z","timestamp":1603790565000},"page":"3520","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["RFI Suppression for SAR Systems Based on Removed Spectrum Iterative Adaptive Approach"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8045-8817","authenticated-orcid":false,"given":"Wei","family":"Xu","sequence":"first","affiliation":[{"name":"College of Information Engineering, Inner Mongolia University of Technology, Hohhot 010050, China"},{"name":"Inner Mongolia Key Laboratory of Radar Technology and Application, Hohhot 010050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4454-5614","authenticated-orcid":false,"given":"Weida","family":"Xing","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Inner Mongolia University of Technology, Hohhot 010050, China"},{"name":"Inner Mongolia Key Laboratory of Radar Technology and Application, Hohhot 010050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chonghua","family":"Fang","sequence":"additional","affiliation":[{"name":"Science and Technology on Electromagnetic Compatibility Laboratory, China Ship Development and Design Center, Wuhan 430064, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7720-1183","authenticated-orcid":false,"given":"Pingping","family":"Huang","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Inner Mongolia University of Technology, Hohhot 010050, China"},{"name":"Inner Mongolia Key Laboratory of Radar Technology and Application, Hohhot 010050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9071-9470","authenticated-orcid":false,"given":"Weixian","family":"Tan","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Inner Mongolia University of Technology, Hohhot 010050, China"},{"name":"Inner Mongolia Key Laboratory of Radar Technology and Application, Hohhot 010050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhiqi","family":"Gao","sequence":"additional","affiliation":[{"name":"College of Information Engineering, Inner Mongolia University of Technology, Hohhot 010050, China"},{"name":"Inner Mongolia Key Laboratory of Radar Technology and Application, Hohhot 010050, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,27]]},"reference":[{"key":"ref_1","unstructured":"Curlander, J.C., and McDonough, R.N. 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