{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T23:40:32Z","timestamp":1773358832051,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2021,8,18]],"date-time":"2021-08-18T00:00:00Z","timestamp":1629244800000},"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":["42074001,41774005,41904039"],"award-info":[{"award-number":["42074001,41774005,41904039"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Postgraduate Research &amp; Practice Innovation Program of China University of Mining and Tech-nology","award":["KYCX19_2163"],"award-info":[{"award-number":["KYCX19_2163"]}]},{"DOI":"10.13039\/501100002858","name":"China Postdoctoral Science Foundation","doi-asserted-by":"publisher","award":["2019M652010, 2019T120477"],"award-info":[{"award-number":["2019M652010, 2019T120477"]}],"id":[{"id":"10.13039\/501100002858","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Suffering from hardware phase biases originating from satellites and the receiver, precise point positioning (PPP) requires a long convergence time to reach centimeter coordinate accuracy, which is a major drawback of this technique and limits its application in time-critical applications. Ambiguity resolution (AR) is the key to a fast convergence time and a high-precision solution for PPP technology and PPP AR products are critical to implement PPP AR. Nowadays, various institutions provide PPP AR products in different forms with different strategies, which allow to enable PPP AR for Global Positioning System (GPS) and Galileo or BeiDou Navigation System (BDS). To give a full evaluation of PPP AR performance with various products, this work comprehensively investigates the positioning performance of GPS-only and multi-GNSS (Global Navigation Satellite System) combination PPP AR with the precise products from CNES, SGG, CODE, and PRIDE Lab using our in-house software. The positioning performance in terms of positioning accuracy, convergence time and fixing rate (FR) as well as time to first fix (TTFF), was assessed by static and kinematic PPP AR models. For GPS-only, combined GPS and Galileo PPP AR with different products, the positioning performances were all comparable with each other. Concretely, the static positioning errors can be reduced by 21.0% (to 0.46 cm), 52.5% (to 0.45 cm), 10.0% (to 1.33 cm) and 21.7% (to 0.33 cm), 47.4% (to 0.34 cm), 9.5% (to 1.16 cm) for GPS-only and GE combination in north, east, up component, respectively, while the reductions are 20.8% (to 1.13 cm), 42.9% (to 1.15 cm), 19.9% (to 3.4 cm) and 20.4% (to 0.72 cm), 44.1% (to 0.66 cm), 10.1% (to 2.44 cm) for kinematic PPP AR. Overall, the positioning performance with CODE products was superior to the others. Furthermore, multi-GNSS observations had significant improvements in PPP performance with float solutions and the TTFF as well as the FR of GPS PPP AR could be improved by adding observations from other GNSS. Additionally, we have released the source code for multi-GNSS PPP AR, anyone can freely access the code and example data from GitHub.<\/jats:p>","DOI":"10.3390\/rs13163266","type":"journal-article","created":{"date-parts":[[2021,8,18]],"date-time":"2021-08-18T22:51:00Z","timestamp":1629327060000},"page":"3266","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":29,"title":["Assessment of GPS\/Galileo\/BDS Precise Point Positioning with Ambiguity Resolution Using Products from Different Analysis Centers"],"prefix":"10.3390","volume":"13","author":[{"given":"Chao","family":"Chen","sequence":"first","affiliation":[{"name":"NASG Key Laboratory of Land Environment and Disaster Monitoring, China University of Mining and Technology, Xuzhou 221116, China"},{"name":"School of Environmental Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1440-0446","authenticated-orcid":false,"given":"Guorui","family":"Xiao","sequence":"additional","affiliation":[{"name":"Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6392-3265","authenticated-orcid":false,"given":"Guobin","family":"Chang","sequence":"additional","affiliation":[{"name":"NASG Key Laboratory of Land Environment and Disaster Monitoring, China University of Mining and Technology, Xuzhou 221116, China"},{"name":"School of Environmental Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5818-6264","authenticated-orcid":false,"given":"Tianhe","family":"Xu","sequence":"additional","affiliation":[{"name":"Institute of Space Science, Shangdong University, Weihai 264209, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3552-3579","authenticated-orcid":false,"given":"Liu","family":"Yang","sequence":"additional","affiliation":[{"name":"NASG Key Laboratory of Land Environment and Disaster Monitoring, China University of Mining and Technology, Xuzhou 221116, China"},{"name":"School of Environmental Science and Spatial Informatics, China University of Mining and Technology, Xuzhou 221116, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,8,18]]},"reference":[{"key":"ref_1","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. Res. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"5005","DOI":"10.1029\/96JB03860","article-title":"Precise point positioning for the efficient and robust analysis of GPS data from large networks","volume":"102","author":"Zumberge","year":"1997","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"15708","DOI":"10.3390\/s131115708","article-title":"On the convergence of ionospheric constrained precise point positioning (IC-PPP) based on undifferential uncombined raw GNSS observations","volume":"13","author":"Zhang","year":"2013","journal-title":"Sensors"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1987","DOI":"10.1002\/2018JB015527","article-title":"Noise Characteristics of High-Rate Multi-GNSS for Subdaily Crustal Deformation Monitoring","volume":"123","author":"Geng","year":"2018","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"54","DOI":"10.1007\/s10291-019-0840-4","article-title":"Rapid displacement determination with a stand-alone multi-GNSS receiver: GPS, Beidou, GLONASS, and Galileo","volume":"23","author":"Su","year":"2019","journal-title":"GPS Solut."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"843","DOI":"10.1007\/s00190-015-0818-0","article-title":"Real-time retrieval of precipitable water vapor from GPS and BeiDou observations","volume":"89","author":"Lu","year":"2015","journal-title":"J. Geod."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"109","DOI":"10.1002\/j.2161-4296.2002.tb00260.x","article-title":"A New Method for Carrier-Phase-Based Precise Point Positioning","volume":"49","author":"Gao","year":"2002","journal-title":"Navigation"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1007\/s10291-016-0527-z","article-title":"Tightly coupled integration of multi-GNSS PPP and MEMS inertial measurement unit data","volume":"21","author":"Gao","year":"2017","journal-title":"GPS Solut."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"5677","DOI":"10.1002\/2013GL057818","article-title":"Temporal point positioning approach for real-time GNSS seismology using a single receiver","volume":"40","author":"Li","year":"2013","journal-title":"Geophys. Res. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Calais, E., Han, J., DeMets, C., and Nocquet, J. (2006). Deformation of the North American plate interior from a decade of continuous GPS measurements. J. Geophys. Res. Solid Earth, 111.","DOI":"10.1029\/2005JB004253"},{"key":"ref_11","doi-asserted-by":"crossref","unstructured":"Geng, J., Chen, X., Pan, Y., Mao, S., Li, C., Zhou, J., and Zhang, K. (2019). PRIDE PPP-AR: An open-source software for GPS PPP ambiguity resolution. GPS Solut., 23.","DOI":"10.1007\/s10291-019-0888-1"},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Xiao, G., Li, P., Gao, Y., and Heck, B. (2019). A unified model for multi-frequency PPP ambiguity resolution and test results with Galileo and BeiDou triple-frequency observations. Remote Sens., 11.","DOI":"10.3390\/rs11020116"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1007\/s00190-007-0187-4","article-title":"Resolution of GPS carrier-phase ambiguities in Precise Point Positioning (PPP) with daily observations","volume":"82","author":"Ge","year":"2008","journal-title":"J. Geod."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1002\/j.2161-4296.2010.tb01772.x","article-title":"Undifferenced GPS ambiguity resolution using the decoupled clock model and ambiguity datum fixing","volume":"57","author":"Collins","year":"2010","journal-title":"Navigation"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1002\/j.2161-4296.2009.tb01750.x","article-title":"Integer ambiguity resolution on undifferenced GPS phase measurements and its application to PPP and satellite precise orbit determination","volume":"56","author":"Laurichesse","year":"2009","journal-title":"J. Navig."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"44","DOI":"10.1007\/s00190-021-01500-0","article-title":"Estimating ambiguity fixed satellite orbit, integer clock and daily bias products for GPS L1\/L2, L1\/L5 and Galileo E1\/E5a, E1\/E5b signals","volume":"95","author":"Duan","year":"2021","journal-title":"J. Geod."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1007\/s10291-019-0929-9","article-title":"Multi-GNSS fractional cycle bias products generation for GNSS ambiguity-fixed PPP at Wuhan University","volume":"24","author":"Hu","year":"2019","journal-title":"GPS Solut."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"78","DOI":"10.1007\/s10291-020-00992-1","article-title":"GPS\u2009+\u2009Galileo\u2009+\u2009BeiDou precise point positioning with triple-frequency ambiguity resolution","volume":"24","author":"Li","year":"2020","journal-title":"GPS Solut."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1007\/s10291-020-01070-2","article-title":"GREAT-UPD: An open-source software for uncalibrated phase delay estimation based on multi-GNSS and multi-frequency observations","volume":"25","author":"Li","year":"2021","journal-title":"GPS Solut."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"82","DOI":"10.1007\/s10291-018-0749-3","article-title":"Estimating satellite phase fractional cycle biases based on Kalman filter","volume":"22","author":"Xiao","year":"2018","journal-title":"GPS Solut."},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Liu, G., Guo, F., Wang, J., Du, M., and Qu, L. (2020). Triple-Frequency GPS Un-Differenced and Uncombined PPP Ambiguity Resolution Using Observable-Specific Satellite Signal Biases. Remote Sens., 12.","DOI":"10.3390\/rs12142310"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1007\/s10291-021-01140-z","article-title":"PPP with integer ambiguity resolution for GPS and Galileo using satellite products from different analysis centers","volume":"25","author":"Glaner","year":"2021","journal-title":"GPS Solut."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2053","DOI":"10.1007\/s00190-019-01301-6","article-title":"A modified phase clock\/bias model to improve PPP ambiguity resolution at Wuhan University","volume":"93","author":"Geng","year":"2019","journal-title":"J. Geod."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1007\/s00190-010-0399-x","article-title":"Integer ambiguity resolution in precise point positioning: Method comparison","volume":"84","author":"Geng","year":"2010","journal-title":"J. Geod."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"519","DOI":"10.1007\/s10291-013-0348-2","article-title":"A comparison of three PPP integer ambiguity resolution methods","volume":"18","author":"Shi","year":"2013","journal-title":"GPS Solut."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"10","DOI":"10.1007\/s00190-019-01335-w","article-title":"On the interoperability of IGS products for precise point positioning with ambiguity resolution","volume":"94","author":"Banville","year":"2020","journal-title":"J. Geod."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1007\/s10291-018-0699-9","article-title":"GAMP: An open-source software of multi-GNSS precise point positioning using undifferenced and uncombined observations","volume":"22","author":"Zhou","year":"2018","journal-title":"GPS Solut."},{"key":"ref_28","unstructured":"Kouba, J. (2021, August 12). A Guide to Using International GNSS Service (IGS) Products. Available online: https:\/\/kb.igs.org\/hc\/en-us\/articles\/201271873-A-Guide-to-Using-the-IGS-Products."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1186\/s43020-021-00047-x","article-title":"Characterization of multi-scale ionospheric irregularities using ground-based and space-based GNSS observations","volume":"2","author":"Peng","year":"2021","journal-title":"Satell. Navig."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"2048","DOI":"10.1016\/j.asr.2017.02.002","article-title":"Handling the satellite inter-frequency biases in triple-frequency observations","volume":"59","author":"Zhao","year":"2017","journal-title":"Adv. Space Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1007\/s10291-015-0464-2","article-title":"Tight integration of ambiguity-fixed PPP and INS: Model description and initial results","volume":"20","author":"Liu","year":"2016","journal-title":"GPS Solut."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"3949","DOI":"10.1029\/JB094iB04p03949","article-title":"Global Positioning System network analysis with phase ambiguity resolution applied to crustal deformation studies in California","volume":"94","author":"Dong","year":"1989","journal-title":"J. Geophys. Res. Solid Earth"},{"key":"ref_33","unstructured":"Teunissen, P., De Jonge, P., and Tiberius, C. (1995, January 26\u201329). The LAMBDA method for fast GPS surveying. Proceedings of the International Symposium \u201cGPS Technology Applications\u201d, Bucharest, Romania."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"552","DOI":"10.1007\/s00190-005-0004-x","article-title":"MLAMBDA: A modified LAMBDA method for integer least-squares estimation","volume":"79","author":"Chang","year":"2005","journal-title":"J. Geod."},{"key":"ref_35","doi-asserted-by":"crossref","unstructured":"Baku\u0142a, M. (2020). Instantaneous Ambiguity Reinitialization and Fast Ambiguity Initialization for L1-L2 GPS Measurements. Sensors, 20.","DOI":"10.3390\/s20205730"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"771","DOI":"10.1007\/s10291-015-0483-z","article-title":"Generating GPS satellite fractional cycle bias for ambiguity-fixed precise point positioning","volume":"20","author":"Li","year":"2015","journal-title":"GPS Solut."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"1487","DOI":"10.1007\/s00190-019-01262-w","article-title":"Determination of GNSS pseudo-absolute code biases and their long-term combination","volume":"93","author":"Villiger","year":"2019","journal-title":"J. Geod."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"840","DOI":"10.1016\/j.asr.2013.07.021","article-title":"Predicting atmospheric delays for rapid ambiguity resolution in precise point positioning","volume":"54","author":"Li","year":"2014","journal-title":"Adv. Space Res."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"849","DOI":"10.1007\/s10291-015-0495-8","article-title":"Multi-GNSS precise point positioning with raw single-frequency and dual-frequency measurement models","volume":"20","author":"Lou","year":"2015","journal-title":"GPS Solut."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"12","DOI":"10.1007\/s10291-019-0925-0","article-title":"Assessment of the positioning performance and tropospheric delay retrieval with precise point positioning using products from different analysis centers","volume":"24","author":"Zhou","year":"2019","journal-title":"GPS Solut."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"639","DOI":"10.1007\/s10291-014-0423-3","article-title":"BeiDou satellite-induced code pseudorange variations: Diagnosis and therapy","volume":"19","author":"Wanninger","year":"2015","journal-title":"GPS Solut."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/16\/3266\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:46:44Z","timestamp":1760165204000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/16\/3266"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,8,18]]},"references-count":41,"journal-issue":{"issue":"16","published-online":{"date-parts":[[2021,8]]}},"alternative-id":["rs13163266"],"URL":"https:\/\/doi.org\/10.3390\/rs13163266","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,8,18]]}}}