{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,1]],"date-time":"2026-03-01T02:41:20Z","timestamp":1772332880530,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2018,1,5]],"date-time":"2018-01-05T00:00:00Z","timestamp":1515110400000},"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":["41574027"],"award-info":[{"award-number":["41574027"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41574030"],"award-info":[{"award-number":["41574030"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["41774035"],"award-info":[{"award-number":["41774035"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2016YFB0501800"],"award-info":[{"award-number":["2016YFB0501800"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In 2015, the plan for global coverage by the Chinese BeiDou Navigation Satellite System was launched. Five global BeiDou experimental satellites (BeiDou-3e) are in orbit for testing. To analyze the performances of precise orbit determination (POD) and precise point positioning (PPP) of onboard BeiDou satellites, about two months of data from 24 tracking stations were used. According to quality analysis of BeiDou-2\/BeiDou-3e data, there is no satellite-induced code bias in BeiDou-3e satellites, which has been found in BeiDou-2 satellites. This phenomenon indicates that the quality issues of pseudorange data in BeiDou satellites have been solved well. POD results indicate that the BeiDou-3e orbit precision is comparable to that of BeiDou-2 satellites. The ambiguity fixed solution improved the orbit consistency of inclined geosynchronous orbit satellites in along-track and cross-track directions, but had little effect in the radial direction. Satellite laser ranging of BeiDou-3e medium Earth orbit satellites (MEOs) achieved a standard deviation of about 4 cm. Differences in clock offset series after the removal of reference clock in overlapping arcs were used to assess clock quality, and standard deviation of clock offset could reach 0.18 ns on average, which was in agreement with the orbit precision. For static PPP, when BeiDou-3e satellites were included, the positioning performance for horizontal components was improved slightly. For kinematic PPP, when global positioning satellites (GPS) were combined with BeiDou-2 and BeiDou-3e satellites, the convergence time was 13.5 min with a precision of 2\u20133 cm for horizontal components, and 3\u20134 cm for the vertical component.<\/jats:p>","DOI":"10.3390\/s18010135","type":"journal-article","created":{"date-parts":[[2018,1,8]],"date-time":"2018-01-08T04:21:21Z","timestamp":1515385281000},"page":"135","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":18,"title":["Performance Analysis of Beidou-2\/Beidou-3e Combined Solution with Emphasis on Precise Orbit Determination and Precise Point Positioning"],"prefix":"10.3390","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0661-4372","authenticated-orcid":false,"given":"Xiaolong","family":"Xu","sequence":"first","affiliation":[{"name":"GNSS Research Center, Wuhan University, 129 Luoyu Road, Wuhan 430079, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Min","family":"Li","sequence":"additional","affiliation":[{"name":"GNSS Research Center, Wuhan University, 129 Luoyu Road, Wuhan 430079, China"},{"name":"Collaborative Innovation Center of Geospatial Technology, 129 Luoyu Road, Wuhan 430079, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wenwen","family":"Li","sequence":"additional","affiliation":[{"name":"GNSS Research Center, Wuhan University, 129 Luoyu Road, Wuhan 430079, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jingnan","family":"Liu","sequence":"additional","affiliation":[{"name":"GNSS Research Center, Wuhan University, 129 Luoyu Road, Wuhan 430079, China"},{"name":"Collaborative Innovation Center of Geospatial Technology, 129 Luoyu Road, Wuhan 430079, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,1,5]]},"reference":[{"key":"ref_1","unstructured":"CSNO (2017, September 12). Development Plan of bds, Available online: http:\/\/www.beidou.gov.cn\/xt\/gfxz\/201712\/P020171221335896007730.pdf."},{"key":"ref_2","unstructured":"CSNO (2017, September 12). Beidou Navigation Satellite System Signal in Space Interface Control Document Open Service Signal (Version 2.1), Available online: http:\/\/www.beidou.gov.cn\/xt\/gfxz\/201710\/P020171202693088949056.pdf."},{"key":"ref_3","unstructured":"CSNO (2017, September 12). China\u2019s BeiDou Navigation Satellite System, Available online: http:\/\/www.beidou.gov.cn\/xt\/gfxz\/201712\/P020171221333863515306.pdf."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1007\/s10291-011-0210-3","article-title":"Characterization of Compass M-1 signals","volume":"16","author":"Hauschild","year":"2012","journal-title":"GPS Solut."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.1007\/s11430-012-4446-8","article-title":"Precise orbit determination of Beidou Satellites with precise positioning","volume":"55","author":"Shi","year":"2012","journal-title":"Sci. China Earth Sci."},{"key":"ref_6","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":"2014","journal-title":"GPS Solut."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"143","DOI":"10.1007\/s00190-015-0862-9","article-title":"Precise orbit determination for quad-constellation satellites at Wuhan University: Strategy, result validation, and comparison","volume":"90","author":"Guo","year":"2016","journal-title":"J. Geod."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1223","DOI":"10.1007\/s00190-016-0920-y","article-title":"Modeling and assessment of triple-frequency BDS precise point positioning","volume":"90","author":"Guo","year":"2016","journal-title":"J. Geod."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1007\/s00190-015-0802-8","article-title":"Accuracy and reliability of multi-GNSS real-time precise positioning: GPS, GLONASS, BeiDou, and Galileo","volume":"89","author":"Li","year":"2015","journal-title":"J. Geod."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Zhao, Q., Wang, G., Liu, Z., Hu, Z., Dai, Z., and Liu, J. (2016). Analysis of BeiDou Satellite Measurements with Code Multipath and Geometry-Free Ionosphere-Free Combinations. Sensors, 16.","DOI":"10.3390\/s16010123"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1225","DOI":"10.1007\/s00190-017-1020-3","article-title":"Initial assessment of the COMPASS\/BeiDou-3: New-generation navigation signals","volume":"91","author":"Zhang","year":"2017","journal-title":"J. Geod."},{"key":"ref_12","first-page":"547","article-title":"The Preliminary Result and Analysis for BD Orbit Determination with Inter-satellite Link Data","volume":"46","author":"Song","year":"2017","journal-title":"Acta Geodetica et Cartographica Sinica"},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Tan, B.F., Yuan, Y.B., Wen, M.Y., Ning, Y.F., and Liu, X.F. (2016). Initial Results of the Precise Orbit Determination for the New-Generation BeiDou Satellites (BeiDou-3) Based on the iGMAS Network. ISPRS Int. J. Geo-Inf., 5.","DOI":"10.3390\/ijgi5110196"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Xie, X., Geng, T., Zhao, Q., Liu, J., and Wang, B. (2017). Performance of BDS-3: Measurement Quality Analysis, Precise Orbit and Clock Determination. Sensors, 17.","DOI":"10.3390\/s17061233"},{"key":"ref_15","unstructured":"Bavaro, M., Curran, J., and Fortuny, J. (2017, September 12). First Signals of BeiDou Phase 3 Acquired at Ispra, Italy. Available online: http:\/\/gpsworld.com\/first-signals-of-beidou-phase-3-acquired-at-ispra-italy\/."},{"key":"ref_16","unstructured":"Cameron, A. (2017, September 12). New BeiDou TMBOC Signal Tracked; Similar to Future GPS L1C Structure. Available online: http:\/\/gpsworld.com\/new-beidou-tmboc-signal-tracked-similar-to-future-gps-l1c-structure\/."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"1671","DOI":"10.1016\/j.asr.2017.01.011","article-title":"The Multi-GNSS Experiment (MGEX) of the International GNSS Service (IGS)\u2014Achievements, prospects and challenges","volume":"59","author":"Montenbruck","year":"2017","journal-title":"Adv. Space Res."},{"key":"ref_18","first-page":"42","article-title":"IGS-MGEX: Preparing the ground for multi-constellation GNSS science","volume":"9","author":"Montenbruck","year":"2014","journal-title":"Inside GNSS"},{"key":"ref_19","unstructured":"Jiao, W. (2014). International GNSS Monitoring and Assessment System (iGMAS) and Latest Progress, China Satellite Navigation Conference (CSNC)."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Lou, Y., Liu, Y., Shi, C., Yao, X., and Zheng, F. (2014). Precise orbit determination of BeiDou constellation based on BETS and MGEX network. Sci. Rep., 4.","DOI":"10.1038\/srep04692"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1007\/s10291-012-0264-x","article-title":"Precise relative positioning using real tracking data from COMPASS GEO and IGSO satellites","volume":"17","author":"Shi","year":"2012","journal-title":"GPS Solut."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1007\/s10291-014-0374-8","article-title":"Multipath analysis of code measurements for BeiDou geostationary satellites","volume":"19","author":"Wang","year":"2014","journal-title":"GPS Solut."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1007\/PL00012778","article-title":"TEQC: The Multi-Purpose Toolkit for GPS\/GLONASS Data","volume":"3","author":"Estey","year":"1999","journal-title":"GPS Solut."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"603","DOI":"10.1007\/BF02899825","article-title":"PANDA software and its preliminary result of positioning and orbit determination","volume":"8","year":"2003","journal-title":"Wuhan Univ. J. Nat. Sci."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1007\/BF03655466","article-title":"Extended orbit modeling techniques at the CODE processing center of the international GPS service for geodynamics (IGS): Theory and initial results","volume":"19","author":"Beutler","year":"1994","journal-title":"Manus. Geod."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1007\/s00190-013-0622-7","article-title":"Initial results of precise orbit and clock determination for COMPASS navigation satellite system","volume":"87","author":"Zhao","year":"2013","journal-title":"J. Geod."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"714","DOI":"10.1007\/BF00867149","article-title":"A new model for GPS yaw attitude","volume":"70","year":"1996","journal-title":"J. Geod."},{"key":"ref_28","doi-asserted-by":"crossref","unstructured":"Sun, J., Jiao, W., Wu, H., and Shi, C. (2013). Precise Orbit Determination for COMPASS IGSO Satellites during Yaw Maneuvers. China Satellite Navigation Conference (CSNC) 2013 Proceedings: Precise Orbit Determination & Positioning Atomic Clock Technique & Time\u2013Frequency System Integrated Navigation & New Methods, Springer.","DOI":"10.1007\/978-3-642-37407-4"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"1005","DOI":"10.1007\/s00190-015-0829-x","article-title":"Estimating the yaw-attitude of BDS IGSO and MEO satellites","volume":"89","author":"Dai","year":"2015","journal-title":"J. Geod."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1015","DOI":"10.1016\/j.asr.2015.06.019","article-title":"GNSS satellite geometry and attitude models","volume":"56","author":"Montenbruck","year":"2015","journal-title":"Adv. Space Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"103","DOI":"10.1007\/s00190-005-0447-0","article-title":"Improving carrier-phase ambiguity resolution in global GPS network solutions","volume":"79","author":"Ge","year":"2005","journal-title":"J. Geod."},{"key":"ref_32","unstructured":"Melbourne, W.G. (1985, January 15\u201319). The case for ranging in GPS-based geodetic systems. Proceedings of the First International Symposium on Precise Positioning with the Global Positioning System, Rockville, MD, USA."},{"key":"ref_33","unstructured":"W\u00fcbbena, G. (1985, January 15\u201319). Software developments for geodetic positioning with GPS using TI-4100 code and carrier measurements. Proceedings of the First International Symposium on Precise Positioning with the Global Positioning System, Rockville, MD, USA."},{"key":"ref_34","unstructured":"Hatch, R. (1982, January 8\u201312). The synergism of GPS code and carrier measurements. Proceedings of the third international symposium on satellite doppler positioning, Physical Sciences Laboratory of New Mexico State University, Las Cruces, NM, USA."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1191","DOI":"10.1007\/s10291-017-0602-0","article-title":"Improving BDS integer ambiguity resolution using satellite-induced code bias correction for precise orbit determination","volume":"21","author":"Geng","year":"2017","journal-title":"GPS Solut."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"L07304","DOI":"10.1029\/2005GL025546","article-title":"Global Mapping Function (GMF): A new empirical mapping function based on numerical weather model data","volume":"33","author":"Boehm","year":"2006","journal-title":"Geophys. Res. Lett."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1007\/BF02522083","article-title":"Contributions to the theory of atmospheric refraction","volume":"107","author":"Saastamoinen","year":"1973","journal-title":"Bulletin G\u00e9od\u00e9sique (1946\u20131975)"},{"key":"ref_38","first-page":"1","article-title":"IERS Conventions (2010)","volume":"36","author":"Petit","year":"2010","journal-title":"IERS Tech. Note"},{"key":"ref_39","doi-asserted-by":"crossref","unstructured":"Bizouard, C., and Gambis, D. (2009). The Combined Solution C04 for Earth Orientation Parameters Consistent with International Terrestrial Reference Frame 2005, Springer.","DOI":"10.1007\/978-3-642-00860-3_41"},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"521","DOI":"10.1007\/s10291-012-0298-0","article-title":"Characterization of between-receiver GPS-Galileo inter-system biases and their effect on mixed ambiguity resolution","volume":"17","author":"Odijk","year":"2013","journal-title":"GPS Solut."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1016\/S0273-1177(02)00277-6","article-title":"The International Laser Ranging Service","volume":"30","author":"Pearlman","year":"2002","journal-title":"Adv. Space Res."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1007\/s00190-014-0774-0","article-title":"Enhanced solar radiation pressure modeling for Galileo satellites","volume":"89","author":"Montenbruck","year":"2014","journal-title":"J. Geod."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1007\/s10291-013-0361-5","article-title":"Galileo orbit determination using combined GNSS and SLR observations","volume":"19","author":"Hackel","year":"2014","journal-title":"GPS Solut."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"138","DOI":"10.1007\/s11430-014-4943-z","article-title":"Quality assessment of onboard GPS receiver and its combination with DORIS and SLR for Haiyang 2A precise orbit determination","volume":"58","author":"Guo","year":"2014","journal-title":"Sci. China Earth Sci."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"29970","DOI":"10.3390\/s151229780","article-title":"Assessment of the Contribution of BeiDou GEO, IGSO, and MEO Satellites to PPP in Asia-Pacific Region","volume":"15","author":"Zhao","year":"2015","journal-title":"Sensors"}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/1\/135\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T14:50:15Z","timestamp":1760194215000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/18\/1\/135"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,1,5]]},"references-count":45,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2018,1]]}},"alternative-id":["s18010135"],"URL":"https:\/\/doi.org\/10.3390\/s18010135","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,1,5]]}}}