{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:32:47Z","timestamp":1760243567184,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2012,3,20]],"date-time":"2012-03-20T00:00:00Z","timestamp":1332201600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>This paper presents a novel method for estimating the absolute phase offset in interferometric synthetic aperture radar (SAR) measurements for digital elevation model (DEM) generation. The method is based on \u201cphase-offset functions (POF),\u201d relating phase offset to topographic height, and are computed for two different overlapping interferometric data acquisitions performed with considerably different incidence angles over the same area of interest. For the purpose of extended mapping, opposite viewing directions are preferred. The two \u201cphase-offset functions\u201d are then linearly combined, yielding a \u201ccombined phase-offset function (CPOF)\u201d. The intersection point of several straight lines (CPOFs), corresponding to different points in the overlap area allows for solving the phase offset for both acquisitions. Aiming at increasing performance and stability, this intersection point is found by means of averaging many points and applying principal component analysis. The method is validated against traditional phase offset estimation with corner reflectors (CR) using real OrbiSAR-1 data in X- and P-band.<\/jats:p>","DOI":"10.3390\/rs4030745","type":"journal-article","created":{"date-parts":[[2012,3,20]],"date-time":"2012-03-20T12:07:51Z","timestamp":1332245271000},"page":"745-761","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["A Phase-Offset Estimation Method for InSAR DEM Generation Based on Phase-Offset Functions"],"prefix":"10.3390","volume":"4","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-8453-2247","authenticated-orcid":false,"given":"Jos\u00e9 Claudio","family":"Mura","sequence":"first","affiliation":[{"name":"National Institute for Space Research (INPE), S\u00e3o Jos\u00e9 dos Campos, 12227-010 SP, Brazil"}]},{"given":"Muriel","family":"Pinheiro","sequence":"additional","affiliation":[{"name":"Orbisat da Amaz\u00f4nia S. A (ORBISAT), S\u00e3o Jos\u00e9 dos Campos, 12244-000 SP, Brazil"}]},{"given":"Rafael","family":"Rosa","sequence":"additional","affiliation":[{"name":"Orbisat da Amaz\u00f4nia S. A (ORBISAT), S\u00e3o Jos\u00e9 dos Campos, 12244-000 SP, Brazil"}]},{"given":"Jo\u00e3o Roberto","family":"Moreira","sequence":"additional","affiliation":[{"name":"Orbisat da Amaz\u00f4nia S. A (ORBISAT), S\u00e3o Jos\u00e9 dos Campos, 12244-000 SP, Brazil"}]}],"member":"1968","published-online":{"date-parts":[[2012,3,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"763","DOI":"10.1109\/PROC.1974.9516","article-title":"Synthetic interferometer radar for topographic mapping","volume":"62","author":"Graham","year":"1974","journal-title":"Proc. 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Principles and Error Theory and Cartographic Applications, Aeronautical Chart and Information Center. ACIC Thechnical Report No 96."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/4\/3\/745\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:49:27Z","timestamp":1760219367000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/4\/3\/745"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,3,20]]},"references-count":20,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2012,3]]}},"alternative-id":["rs4030745"],"URL":"https:\/\/doi.org\/10.3390\/rs4030745","relation":{},"ISSN":["2072-4292"],"issn-type":[{"type":"electronic","value":"2072-4292"}],"subject":[],"published":{"date-parts":[[2012,3,20]]}}}