{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T00:29:05Z","timestamp":1760228945485,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2022,5,26]],"date-time":"2022-05-26T00:00:00Z","timestamp":1653523200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2021YFC3001903","62101036","61971037","31727901","61960206009"],"award-info":[{"award-number":["2021YFC3001903","62101036","61971037","31727901","61960206009"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"name":"National Natural Science Foundation of China","award":["2021YFC3001903","62101036","61971037","31727901","61960206009"],"award-info":[{"award-number":["2021YFC3001903","62101036","61971037","31727901","61960206009"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Ground-based interferometric synthetic aperture radar (GB-InSAR) technology can be applied to generate a digital elevation model (DEM) with high spatial resolution and high accuracy. Phase unwrapping is a critical procedure, and unwrapping errors cannot be effectively avoided in the interferometric measurements of terrains with discontinuous heights. In this paper, an improved multi-baseline phase unwrapping (MB PU) method for GB-InSAR is proposed. This method combines the advantages of the cluster-analysis-based MB PU algorithm and the minimum cost flow (MCF) method. A cluster-analysis-based MB PU algorithm (CA-based MB PU) is firstly utilized to unwrap the clustered pixels with high phase quality. Under the topological constraints of a triangulation network, the connectivity graph of any non-clustered pixel is established with its adjacent unwrapped cluster pixels. Then, the absolute phase of these non-clustered pixels can be identified using the MCF method. Additionally, a spatial-distribution-based denoising algorithm is utilized to denoise the data in order to further improve the accuracy of the phase unwrapping. The DEM generated by one GB-InSAR is compared with that generated by light detection and ranging (LiDAR). Both simulated and experimental datasets are utilized to verify the effectiveness and robustness of this improved method.<\/jats:p>","DOI":"10.3390\/rs14112543","type":"journal-article","created":{"date-parts":[[2022,5,31]],"date-time":"2022-05-31T00:25:12Z","timestamp":1653956712000},"page":"2543","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["An Improved Multi-Baseline Phase Unwrapping Method for GB-InSAR"],"prefix":"10.3390","volume":"14","author":[{"given":"Zihao","family":"Lin","sequence":"first","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"}]},{"given":"Yan","family":"Duan","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2765-2976","authenticated-orcid":false,"given":"Yunkai","family":"Deng","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Key Laboratory of Electronic and Information Technology in Satellite Navigation (Beijing Institute of Technology), Ministry of Education, Beijing 100081, China"}]},{"given":"Weiming","family":"Tian","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"},{"name":"Beijing Institute of Technology Chongqing Innovation Center, Chongqing 401120, China"},{"name":"Advanced Technology Research Institute, Beijing Institute of Technology, Jinan 250300, China"}]},{"given":"Zheng","family":"Zhao","sequence":"additional","affiliation":[{"name":"Radar Research Lab, School of Information and Electronics, Beijing Institute of Technology, Beijing 100081, China"}]}],"member":"1968","published-online":{"date-parts":[[2022,5,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Pieraccini, M., and Miccinesi, L. 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