caa a22 4500 606162178 CHVBK 20210128100638.0 cr unu---uuuuu 210128e20150101xx s 000 0 eng 10.1007/s10291-014-0364-x doi (NATIONALLICENCE)springer-10.1007/s10291-014-0364-x An 18-element GEO broadcast ephemeris based on non-singular elements [Elektronische Daten] [Lan Du, Zhongkai Zhang, Jin Zhang, Li Liu, Rui Guo, Feng He] Compass/Beidou2 uses uniform GPS-type broadcast ephemerides for its mixed constellation, which consists of geostationary earth orbit (GEO), inclined geosynchronous orbit and medium earth orbit satellites. The ephemeris parameters adopted by Compass are singular for the small inclinations of GEOs, and some intermediate orbital planes are currently used to avoid the singularities of parameter fitting. To directly deal with GEOs, an improved 18-element broadcast ephemeris is proposed, which consists of the non-singular elements and some correction terms. First, the non-singular elements are used to enable the orbit representation of GEOs to be completely free from the singularity. Second, two additional parameters, which express the predominant characteristics of east-west drift of the subsatellite point of GEO, are added into the correction terms for improving the modeling precision. Third, the user satellite position and velocity computation model based on the designed broadcast ephemeris parameters are presented. Simulation results show that the fitting arc length of the proposed broadcast ephemeris can be reduced to as short as 2h, and that the improvement of the fitting user range error (URE) is obtained. The typical RMS of the fitting URE obtained in a non-eclipse period is less than 1 and 5mm for 2- and 3-h fitting arcs, respectively. Springer-Verlag Berlin Heidelberg, 2014 Compass nationallicence GEO satellites nationallicence Broadcast ephemeris parameters nationallicence Non-singular orbital elements nationallicence Perturbation nationallicence Eclipse nationallicence Du Lan Zhengzhou Institute of Surveying and Mapping, 450052, Zhengzhou, China aut Zhang Zhongkai Zhengzhou Institute of Surveying and Mapping, 450052, Zhengzhou, China aut Zhang Jin National University of Defense Technology, 410073, Changsha, China aut Liu Li Beijing Global Information Application and Development Center, 100094, Beijing, China aut Guo Rui Beijing Global Information Application and Development Center, 100094, Beijing, China aut He Feng Beijing Global Information Application and Development Center, 100094, Beijing, China aut GPS Solutions Springer Berlin Heidelberg 19/1(2015-01-01), 49-59 1080-5370 19:1<49 2015 19 10291 https://doi.org/10.1007/s10291-014-0364-x text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10291-014-0364-x text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Du Lan Zhengzhou Institute of Surveying and Mapping, 450052, Zhengzhou, China aut NATIONALLICENCE 700 1- Zhang Zhongkai Zhengzhou Institute of Surveying and Mapping, 450052, Zhengzhou, China aut NATIONALLICENCE 700 1- Zhang Jin National University of Defense Technology, 410073, Changsha, China aut NATIONALLICENCE 700 1- Liu Li Beijing Global Information Application and Development Center, 100094, Beijing, China aut NATIONALLICENCE 700 1- Guo Rui Beijing Global Information Application and Development Center, 100094, Beijing, China aut NATIONALLICENCE 700 1- He Feng Beijing Global Information Application and Development Center, 100094, Beijing, China aut NATIONALLICENCE 773 0- GPS Solutions Springer Berlin Heidelberg 19/1(2015-01-01), 49-59 1080-5370 19:1<49 2015 19 10291