{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,5]],"date-time":"2026-03-05T22:04:22Z","timestamp":1772748262967,"version":"3.50.1"},"reference-count":26,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,6,8]],"date-time":"2020-06-08T00:00:00Z","timestamp":1591574400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"The National Key Research and Development Plan of China","award":["2016YFB0502100"],"award-info":[{"award-number":["2016YFB0502100"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>At present, Global Position System (GPS) navigation ephemeris mainly broadcasts satellite orbits with meter-level precision for standard point positioning and precise relative positioning. With the rapid development of real-time precise point positioning (PPP), the receiver or smartphone has begun to demand more and more convenient, continuous, and reliable access to real-time services of precise orbits. Therefore, this study proposes a solution of utilizing the 18-parameter ephemeris to directly broadcast ultra-rapid precise predicted orbits with centimeter-level precision for real-time PPP. For the first time in GPS, the difference in the PPP results between the precise orbits and the calculated orbits broadcasted from the generated ephemeris parameters is supplied as follows: (1) During the validity period of 2 h, root mean square (RMS) of the relative distance offsets between the results of PPP with the precise orbits and the results of PPP the 18-parameter ephemeris is only 0.0098 m. (2) Within 15 min after the validity period of 2 h, RMS of the relative distance offsets between the results of PPP with the precise orbits and the results of PPP with the predicted orbits by 18-parameter ephemeris is only 0.0057 m. Consequently, the 18-parameter ephemeris is feasible and advisable to broadcast precise predicted orbits for real-time PPP applications. Compared with the classic precise orbits broadcast mode with the orbit corrections defined by the radio technical commission for maritime services standards 10403.2 (RTCM), the mode of broadcasting the precise orbits with the 18-parameter ephemeris achieved the following improvements in convenience, continuity, and reliability: (1) The calculation of satellite position is the same as that of the navigation ephemeris excluding the additional correction operations required to the RTCM; (2) the amount of broadcast parameters was reduced by 20 times; (3) the length of the validity period was expanded 120 times, where the longer valid period helped to overcome the orbit corrections loss caused by RTCM stream failures; and (4) within 15 min after the validity period, the predicted orbits with an accuracy of 2 cm could still be provided by the 18-parameter ephemeris, which can ensure the real-time services of precise orbits in the case of a 15 min communication interruption of the RTCM orbit correction data stream.<\/jats:p>","DOI":"10.3390\/s20113276","type":"journal-article","created":{"date-parts":[[2020,6,9]],"date-time":"2020-06-09T06:34:16Z","timestamp":1591684456000},"page":"3276","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["A Smart Realtime Service to Broadcast the Precise Orbits of GPS Satellite and Its Performance on Precise Point Positioning"],"prefix":"10.3390","volume":"20","author":[{"given":"Dehai","family":"Li","sequence":"first","affiliation":[{"name":"Chinese Academy of Surveying and Mapping, No.28, Lianhuachi West Road, Beijing 100830, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei","family":"Yan","sequence":"additional","affiliation":[{"name":"Tianjin Institute of Surveying and Mapping, Changling Road, Tianjin 300381, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jinzhong","family":"Mi","sequence":"additional","affiliation":[{"name":"Chinese Academy of Surveying and Mapping, No.28, Lianhuachi West Road, Beijing 100830, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yamin","family":"Dang","sequence":"additional","affiliation":[{"name":"Chinese Academy of Surveying and Mapping, No.28, Lianhuachi West Road, Beijing 100830, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunbin","family":"Yuan","sequence":"additional","affiliation":[{"name":"Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Science, Xiaohongshan West Road, Wuhan 430071, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1212-0715","authenticated-orcid":false,"given":"Xingli","family":"Gan","sequence":"additional","affiliation":[{"name":"The 54th Research Institute of China Electronics Technology Group Corporation, Shijiazhuang 050081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"565","DOI":"10.1007\/s10291-015-0467-z","article-title":"Performance of real-time Precise Point Positioning using IGS real-time service","volume":"20","author":"Elsobeiey","year":"2015","journal-title":"GPS Solut."},{"key":"ref_2","unstructured":"Kouba, J. (2020, May 22). A Guide to Using International GNSS Service (IGS) Product. Available online: https:\/\/kb.igs.org\/hc\/en-us\/articles\/201271873-a-guide-to-using-the-igs-products."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"405","DOI":"10.1007\/s00190-013-0611-x","article-title":"A method for improving uncalibrated phase delay estimation and ambiguity-fixing in real-time precise point positioning","volume":"87","author":"Li","year":"2013","journal-title":"J. Geod."},{"key":"ref_4","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_5","doi-asserted-by":"crossref","first-page":"59","DOI":"10.1515\/arsa-2015-0005","article-title":"GNSS-Warp Software for Real-Time Precise Point Positioning","volume":"50","author":"Hadas","year":"2015","journal-title":"Artif. Satell."},{"key":"ref_6","unstructured":"RTCM (2013). RTCM Standard 10403.2 Differential GNSS Services\u2014Version 3, RTCM Special Committee 104; RTCM."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1007\/s10291-012-0278-4","article-title":"Short-term analysis of GNSS clocks","volume":"17","author":"Hauschild","year":"2012","journal-title":"GPS Solut."},{"key":"ref_8","doi-asserted-by":"crossref","unstructured":"Shi, J., Wang, G., Han, X., and Guo, J. (2017). Impacts of Satellite Orbit and Clock on Real-Time GPS Point and Relative Positioning. Sensors, 17.","DOI":"10.3390\/s17061363"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"315","DOI":"10.1007\/s10291-010-0191-7","article-title":"Satellite clock estimation at 1 Hz for realtime kinematic PPP applications","volume":"15","author":"Zhang","year":"2010","journal-title":"GPS Solut."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1007\/s10291-014-0369-5","article-title":"IGS RTS precise orbits and clocks verification and quality degradation over time","volume":"19","author":"Hadas","year":"2014","journal-title":"GPS Solut."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"367","DOI":"10.1016\/j.asr.2017.08.037","article-title":"GNSS global real-time augmentation positioning: Real-time precise satellite clock estimation, prototype system construction and performance analysis","volume":"61","author":"Chen","year":"2018","journal-title":"Adv. Space Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1007\/s10291-003-0065-3","article-title":"Broadcast versus precise GPS ephemerides: A historical perspective","volume":"7","author":"Warren","year":"2003","journal-title":"GPS Solut."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1007\/s10291-014-0390-8","article-title":"Broadcast versus precise ephemerides: A multi-GNSS perspective","volume":"19","author":"Montenbruck","year":"2014","journal-title":"GPS Solut."},{"key":"ref_14","unstructured":"IGS-RTS (2020, May 22). International GNSS Real-time Service. Available online: http:\/\/www.igs.org\/rts."},{"key":"ref_15","unstructured":"IGS (2020, May 22). The International GNSS Service. Available online: http:\/\/www.igs.org\/products."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"45","DOI":"10.1007\/s00190-018-1138-y","article-title":"Improving multi-GNSS ultra-rapid orbit determination for real-time precise point positioning","volume":"93","author":"Li","year":"2018","journal-title":"J. Geod."},{"key":"ref_17","unstructured":"BKG (2013). BKG Ntrip Client (BNC) Version 2.8 Manual, Federal Agency for Cartography and Geodesy."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1007\/s10291-014-0364-x","article-title":"An 18-element GEO broadcast ephemeris based on non-singular elements","volume":"19","author":"Du","year":"2014","journal-title":"GPS Solut."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"3020","DOI":"10.1016\/j.asr.2018.03.041","article-title":"Multi-GNSS Signal-in-Space range error assessment\u2014Methodology and Results","volume":"61","author":"Montenbruck","year":"2018","journal-title":"Adv. Space Res."},{"key":"ref_20","doi-asserted-by":"crossref","unstructured":"Hadas, T., Kazmierski, K., and So\u015bnica, K. (2019). Performance of Galileo-only dual-frequency absolute positioning using the fully serviceable Galileo constellation. GPS Solut., 23.","DOI":"10.1007\/s10291-019-0900-9"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Ka\u017amierski, K., So\u015bnica, K., and Hadas, T. (2017). Quality assessment of multi-GNSS orbits and clocks for real-time precise point positioning. GPS Solut., 22.","DOI":"10.1007\/s10291-017-0678-6"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"439","DOI":"10.1007\/s10291-011-0243-7","article-title":"Optimal design of broadcast ephemeris parameters for a navigation satellite system","volume":"16","author":"Fu","year":"2011","journal-title":"GPS Solut."},{"key":"ref_23","unstructured":"IS-GPS (2005). Interface Specification Document IS-GPS-705D, ARINC Engineering Services."},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Xie, X., Geng, T., Zhao, Q., Liu, X., Zhang, Q., and Liu, J. (2018). Design and validation of broadcast ephemeris for low Earth orbit satellites. GPS Solut., 22.","DOI":"10.1007\/s10291-018-0719-9"},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Montenbruck, O., and Gill, E. (2000). Satellite Orbits: Models, Methods, and Applications, Springer.","DOI":"10.1007\/978-3-642-58351-3"},{"key":"ref_26","unstructured":"Xu, G., and Xu, Y. (2007). GPS: Theory, Algorithms and Applications, Springer."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/11\/3276\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T09:36:52Z","timestamp":1760175412000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/20\/11\/3276"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,6,8]]},"references-count":26,"journal-issue":{"issue":"11","published-online":{"date-parts":[[2020,6]]}},"alternative-id":["s20113276"],"URL":"https:\/\/doi.org\/10.3390\/s20113276","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2020,6,8]]}}}