{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,25]],"date-time":"2026-03-25T14:47:56Z","timestamp":1774450076744,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2022,4,11]],"date-time":"2022-04-11T00:00:00Z","timestamp":1649635200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61701047 and 42074033"],"award-info":[{"award-number":["61701047 and 42074033"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Hunan Provincial Natural Science Foundation of China","award":["2019JJ50639"],"award-info":[{"award-number":["2019JJ50639"]}]},{"name":"Scientific Research Fund of Hunan Provincial Education Department","award":["20B038 and 18A148"],"award-info":[{"award-number":["20B038 and 18A148"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Multibaseline (MB) phase unwrapping (PU) is a key processing technique in MB interferometric synthetic aperture radar (InSAR). As one of the most popular methods, the cluster analysis (CA)-based MBPU method often suffers from the problem of low noise robustness. Therefore, the block-matching and 3D filtering (BM3D) algorithm, one of the most effective filtering methods for image denoising, is applied to improve the performance of the method. Five different filtering strategies for applying BM3D are proposed in the paper: interferogram filtering (IFF), intercept filtering (ICF), cluster number filtering (CNF), unwrapped phase filtering (UPF), and simultaneous filtering (STF). In particular, while keeping the general structure of BM3D, four different similarity measures are defined for interferograms, intercepts, clusters, and unwrapped phases to accommodate the special characteristics of different filtering objects. Experiments on synthesized and real InSAR datasets prove their feasibility and effectiveness, and the experiment results show that (1) the PU accuracy and robustness of the CA-based MBPU method can be greatly improved by adding BM3D denoising; (2) simultaneous filtering of interferograms, intercepts, cluster numbers, and unwrapped phases works best, but with the worst time complexity; (3) when filtering is performed for only one object of the CA-based MBPU method, the filtering effect of CNF and UPF is better than that of IFF and ICF; and (4), considering the three indicators of PUSR, NRSE, and time consumption, CNF and UPF should be the best choices.<\/jats:p>","DOI":"10.3390\/rs14081836","type":"journal-article","created":{"date-parts":[[2022,4,12]],"date-time":"2022-04-12T02:48:59Z","timestamp":1649731739000},"page":"1836","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["BM3D Denoising for a Cluster-Analysis-Based Multibaseline InSAR Phase-Unwrapping Method"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7100-826X","authenticated-orcid":false,"given":"Zhihui","family":"Yuan","sequence":"first","affiliation":[{"name":"School of Electrical and Information Engineering, Changsha University of Science and Technology, Changsha 410114, China"},{"name":"Laboratory of Radar Remote Sensing Applications, Changsha University of Science and Technology, Changsha 410014, China"},{"name":"Hunan Province Key Laboratory of Electric Power Robot, Changsha University of Science and Technology, Changsha 410114, China"}]},{"given":"Tianjiao","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Changsha University of Science and Technology, Changsha 410114, China"},{"name":"Laboratory of Radar Remote Sensing Applications, Changsha University of Science and Technology, Changsha 410014, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7741-4899","authenticated-orcid":false,"given":"Xuemin","family":"Xing","sequence":"additional","affiliation":[{"name":"Laboratory of Radar Remote Sensing Applications, Changsha University of Science and Technology, Changsha 410014, China"},{"name":"School of Traffic and Transportation Engineering, Changsha University of Science and Technology, Changsha 410114, China"}]},{"given":"Wei","family":"Peng","sequence":"additional","affiliation":[{"name":"Laboratory of Radar Remote Sensing Applications, Changsha University of Science and Technology, Changsha 410014, China"},{"name":"School of Traffic and Transportation Engineering, Changsha University of Science and Technology, Changsha 410114, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2432-9583","authenticated-orcid":false,"given":"Lifu","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Electrical and Information Engineering, Changsha University of Science and Technology, Changsha 410114, China"},{"name":"Laboratory of Radar Remote Sensing Applications, Changsha University of Science and Technology, Changsha 410014, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"R1","DOI":"10.1088\/0266-5611\/14\/4\/001","article-title":"Synthetic aperture radar interferometry","volume":"14","author":"Bamler","year":"1998","journal-title":"Inverse Probl."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"333","DOI":"10.1109\/5.838084","article-title":"Synthetic aperture radar interferometry","volume":"88","author":"Rosen","year":"2000","journal-title":"Proc. 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