{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,15]],"date-time":"2026-06-15T17:55:45Z","timestamp":1781546145861,"version":"3.54.5"},"reference-count":29,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2020,11,14]],"date-time":"2020-11-14T00:00:00Z","timestamp":1605312000000},"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":["61771197"],"award-info":[{"award-number":["61771197"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100003399","name":"Science and Technology Commission of Shanghai Municipality","doi-asserted-by":"publisher","award":["14DZ2260800"],"award-info":[{"award-number":["14DZ2260800"]}],"id":[{"id":"10.13039\/501100003399","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>To provide high-precision positioning for Internet of Things (IoT) scenarios, we optimize the indoor positioning technique based on Ultra-Wideband (UWB) Time Difference of Arrival (TDOA) equipment. This paper analyzes sources of positioning error and improves the time synchronization algorithm based on the synchronization packet. Then we use the labels of the known position to further optimize the time synchronization performance, and hence improve TDOA measurements. After time synchronization optimization, a Weighted Least Square (WLS) and Taylor coordination algorithm is derived. Experiments show that our optimization reduces the average positioning error from 54.8 cm to 12.6 cm.<\/jats:p>","DOI":"10.3390\/s20226513","type":"journal-article","created":{"date-parts":[[2020,11,16]],"date-time":"2020-11-16T21:48:52Z","timestamp":1605563332000},"page":"6513","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Optimization of Time Synchronization and Algorithms with TDOA Based Indoor Positioning Technique for Internet of Things"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8381-3714","authenticated-orcid":false,"given":"Kun","family":"Zhao","sequence":"first","affiliation":[{"name":"Engineering Center of SHMEC for Space Information and GNSS, East China Normal University, Shanghai 200241, China"},{"name":"Shanghai Key Laboratory of Multidimensional Information Processing, East China Normal University, Shanghai 200241, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tiantian","family":"Zhao","sequence":"additional","affiliation":[{"name":"Alibaba Xixi Park, Yu Hang District, Hangzhou 311121, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhengqi","family":"Zheng","sequence":"additional","affiliation":[{"name":"Engineering Center of SHMEC for Space Information and GNSS, East China Normal University, Shanghai 200241, China"},{"name":"Shanghai Key Laboratory of Multidimensional Information Processing, East China Normal University, Shanghai 200241, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chao","family":"Yu","sequence":"additional","affiliation":[{"name":"Engineering Center of SHMEC for Space Information and GNSS, East China Normal University, Shanghai 200241, China"},{"name":"Shanghai Key Laboratory of Multidimensional Information Processing, East China Normal University, Shanghai 200241, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Difeng","family":"Ma","sequence":"additional","affiliation":[{"name":"Engineering Center of SHMEC for Space Information and GNSS, East China Normal University, Shanghai 200241, China"},{"name":"Shanghai Key Laboratory of Multidimensional Information Processing, East China Normal University, Shanghai 200241, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9784-3703","authenticated-orcid":false,"given":"Khaled","family":"Rabie","sequence":"additional","affiliation":[{"name":"Department of Engineering, Manchester Metropolitan University, Manchester M15 6BH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8632-7439","authenticated-orcid":false,"given":"Rupak","family":"Kharel","sequence":"additional","affiliation":[{"name":"Department of Computing and Mathematics, Manchester Metropolitan University, Manchester M15 6BH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,11,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2568","DOI":"10.1109\/COMST.2019.2911558","article-title":"A Survey of Indoor Localization Systems and Technologies","volume":"21","author":"Zafari","year":"2019","journal-title":"IEEE Commun. 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