{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T11:59:35Z","timestamp":1783511975337,"version":"3.55.0"},"reference-count":34,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2024,8,15]],"date-time":"2024-08-15T00:00:00Z","timestamp":1723680000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Natural Science Foundation of Hebei Province, China","award":["D2024523002"],"award-info":[{"award-number":["D2024523002"]}]},{"name":"Natural Science Foundation of Hebei Province, China","award":["2023YFE0208400"],"award-info":[{"award-number":["2023YFE0208400"]}]},{"name":"Natural Science Foundation of Hebei Province, China","award":["2022YFC2204601"],"award-info":[{"award-number":["2022YFC2204601"]}]},{"name":"Natural Science Foundation of Hebei Province, China","award":["2023YFC2206100"],"award-info":[{"award-number":["2023YFC2206100"]}]},{"name":"Natural Science Foundation of Hebei Province, China","award":["2023-JC-QN-0278"],"award-info":[{"award-number":["2023-JC-QN-0278"]}]},{"name":"National Key Research and Development Program of China","award":["D2024523002"],"award-info":[{"award-number":["D2024523002"]}]},{"name":"National Key Research and Development Program of China","award":["2023YFE0208400"],"award-info":[{"award-number":["2023YFE0208400"]}]},{"name":"National Key Research and Development Program of China","award":["2022YFC2204601"],"award-info":[{"award-number":["2022YFC2204601"]}]},{"name":"National Key Research and Development Program of China","award":["2023YFC2206100"],"award-info":[{"award-number":["2023YFC2206100"]}]},{"name":"National Key Research and Development Program of China","award":["2023-JC-QN-0278"],"award-info":[{"award-number":["2023-JC-QN-0278"]}]},{"name":"Natural Science Basic Research Project of Shaanxi Province","award":["D2024523002"],"award-info":[{"award-number":["D2024523002"]}]},{"name":"Natural Science Basic Research Project of Shaanxi Province","award":["2023YFE0208400"],"award-info":[{"award-number":["2023YFE0208400"]}]},{"name":"Natural Science Basic Research Project of Shaanxi Province","award":["2022YFC2204601"],"award-info":[{"award-number":["2022YFC2204601"]}]},{"name":"Natural Science Basic Research Project of Shaanxi Province","award":["2023YFC2206100"],"award-info":[{"award-number":["2023YFC2206100"]}]},{"name":"Natural Science Basic Research Project of Shaanxi Province","award":["2023-JC-QN-0278"],"award-info":[{"award-number":["2023-JC-QN-0278"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Ambiguity resolution (AR) can markedly enhance the precision of precise point positioning (PPP) and accelerate the convergence process. The decoupled clock model represents a pivotal approach for ambiguity resolution, yet current research on this topic is largely confined to GPS. Consequently, in this study, we extend the investigation of the decoupled clock model to multi-GNSS. Firstly, based on the conventional model, we derive the multi-GNSS decoupled clock estimation model and the precise point positioning with ambiguity resolution (PPP-AR) model. Secondly, we provide a detailed explanation of the estimation process for the multi-GNSS decoupled clock estimation. To validate the efficacy of the proposed model, we conduct multi-GNSS decoupled clock estimation and PPP-AR experiments using six days of observation data. The results demonstrate that the decoupled clocks of GPS, Galileo, and BDS-3 can all achieve high accuracy, thus fully meeting the requirement of ambiguity resolution. In terms of positioning performance, the joint three systems have higher positioning accuracy, reaching 3.10 cm and 6.13 cm in horizontal and vertical directions, respectively. Furthermore, the convergence time (CT) and time to first fix (TTFF) are shortened, to 23.13 min and 13.65 min, respectively. The experimental findings indicate that the proposed multi-GNSS decoupled clock model exhibits high precision and rapid positioning service capabilities.<\/jats:p>","DOI":"10.3390\/rs16162999","type":"journal-article","created":{"date-parts":[[2024,8,15]],"date-time":"2024-08-15T09:29:41Z","timestamp":1723714181000},"page":"2999","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Multi-GNSS Precise Point Positioning with Ambiguity Resolution Based on the Decoupled Clock Model"],"prefix":"10.3390","volume":"16","author":[{"given":"Shuai","family":"Liu","sequence":"first","affiliation":[{"name":"The 54th Research Institute of CETC, Shijiazhuang 050081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yunbin","family":"Yuan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Geodesy and Earth\u2019s Dynamics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiaosong","family":"Guo","sequence":"additional","affiliation":[{"name":"The 54th Research Institute of CETC, Shijiazhuang 050081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kezhi","family":"Wang","sequence":"additional","affiliation":[{"name":"The 54th Research Institute of CETC, Shijiazhuang 050081, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gongwei","family":"Xiao","sequence":"additional","affiliation":[{"name":"School of Communications and Information Engineering (School of Artificial Intelligence), Xi\u2019an University of Posts and Telecommunications, Xi\u2019an 710121, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,8,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1007\/PL00012883","article-title":"Precise point positioning using IGS orbit and clock products","volume":"5","author":"Kouba","year":"2001","journal-title":"GPS Solut."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"651","DOI":"10.1029\/GL017i005p00651","article-title":"Geodetic point positioning with GPS carrier beat phase data from the CASA UNO Experiment","volume":"17","author":"Malys","year":"1990","journal-title":"Geophys. 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