{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,13]],"date-time":"2026-07-13T22:44:03Z","timestamp":1783982643689,"version":"3.55.0"},"reference-count":32,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,3,16]],"date-time":"2024-03-16T00:00:00Z","timestamp":1710547200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Guangxi Bagui Scholar Foundation","award":["2019A51"],"award-info":[{"award-number":["2019A51"]}]},{"name":"Guangxi Bagui Scholar Foundation","award":["DH202304"],"award-info":[{"award-number":["DH202304"]}]},{"name":"Guangxi Bagui Scholar Foundation","award":["2023YCXS036"],"award-info":[{"award-number":["2023YCXS036"]}]},{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology","award":["2019A51"],"award-info":[{"award-number":["2019A51"]}]},{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology","award":["DH202304"],"award-info":[{"award-number":["DH202304"]}]},{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology","award":["2023YCXS036"],"award-info":[{"award-number":["2023YCXS036"]}]},{"name":"Innovation Project of GUET Graduate Education","award":["2019A51"],"award-info":[{"award-number":["2019A51"]}]},{"name":"Innovation Project of GUET Graduate Education","award":["DH202304"],"award-info":[{"award-number":["DH202304"]}]},{"name":"Innovation Project of GUET Graduate Education","award":["2023YCXS036"],"award-info":[{"award-number":["2023YCXS036"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Two-dimensional phase unwrapping (2-D PU) is vital for reconstructing Earth\u2019s surface topography and displacement from interferometric synthetic aperture radar (InSAR) data. Conventional algorithms rely on the postulate, but this assumption is often insufficient due to abrupt topographic changes and severe noise. To address this challenge, our research proposes a novel approach utilizing deep convolutional neural networks inspired by the U-Net architecture to estimate phase gradient information. Our approach involves downsampling the input data to extract crucial features, followed by upsampling to restore spatial resolution. We incorporate two attention mechanisms\u2014feature pyramid attention (FPA) and global attention upsample (GAU)\u2014and a residual structure in the network\u2019s structure. Thus, we construct ResDANet (residual and dual attention net). We rigorously train ResDANet utilizing simulated datasets and employ an L1-norm objective function to minimize the disparity between unwrapped phase gradients and those calculated by ResDANet, yielding the final 2-D PU results. The network is rigorously trained using two distinct training strategies and encompassing three types of simulated datasets. ResDANet exhibits excellent robust performance and efficiency on simulated data and real data, such as China\u2019s Three Gorges and an Italian volcano.<\/jats:p>","DOI":"10.3390\/rs16061058","type":"journal-article","created":{"date-parts":[[2024,3,18]],"date-time":"2024-03-18T04:25:15Z","timestamp":1710735915000},"page":"1058","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Robust Two-Dimensional InSAR Phase Unwrapping via FPA and GAU Dual Attention in ResDANet"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-6888-535X","authenticated-orcid":false,"given":"Xiaomao","family":"Chen","sequence":"first","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-5673-5843","authenticated-orcid":false,"given":"Shanshan","family":"Zhang","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaofeng","family":"Qin","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jinfeng","family":"Lin","sequence":"additional","affiliation":[{"name":"Guangxi Key Laboratory of Precision Navigation Technology and Application, Guilin University of Electronic Technology, Guilin 541004, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,3,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2470","DOI":"10.1364\/AO.21.002470","article-title":"Analysis of the phase unwrapping algorithm","volume":"21","author":"Itoh","year":"1982","journal-title":"Appl. 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