The BeiDou Navigation Satellite System (BDS) is experiencing a transition from regional (BDS-2) to global (BDS-3) service capability, and both BDS-2 and BDS-3 jointly provide primary navigation services. Using approximately 5-years of ephemerides since January 2016 from the International Global Navigation Satellite Systems (GNSS) Service (IGS) and precise products from Wuhan University (WHU), we provide an assessment of signal-in-space (SIS) errors (SISE) for both BDS-2 and BDS-3 broadcast ephemerides. Due to the new inter-satellite links (ISLs) adopted by the BDS-3 satellites, the percentages of ages of data, ephemeris (AODEs) and ages of data, clock (AODCs) shorter than one hour are 96.48% and 95.78%, respectively, compared to 72.16% and 79.25% of BDS-2. The broadcast orbit performance is also improved by the ISLs. The 3D root mean square errors (RMSEs) of the geosynchronous earth orbit (GEO) broadcast orbits are 6.89 m and 2.45 m for BDS-2 and BDS-3, respectively, while they are 2.04 m and 0.75 m for the inclined geosynchronous orbit (IGSO) and 1.99 m and 0.47 m for the medium earth orbit (MEO). It is found in this contribution that the orientations implied in the BDS-2 and BDS-3 orbital realizations of the terrestrial reference frame are more scattered than those of other navigation systems (i.e., GPS, GLONASS and Galileo). The non-radial orbit errors of BDS-3 (BDS-2) could be improved by approximately 0.2 m (0.1 m) when the estimates of the rotation parameters were considered. It is discovered that a linear pattern in the satellite laser ranging (SLR) residuals is characterized by BDS broadcast orbits, and orbit models might need to be improved. In terms of the broadcast clock error, the averages of the standard deviations (SD) are 0.4 m and 0.2 m for BDS-2 and BDS-3, respectively. However, significant satellite-dependent nonzero clock bias is also observed for the BDS-3 satellites, and this bias could be partly reduced using the differential code bias (DCB) product. The change of correlation between orbit radial component and clock errors from − 0.30 to 0.31 is found for BDS-2 GEO satellites when the reference point of ephemerides was switched from antenna to center of mass. Meanwhile, the reference point switch induces a change of correlation between along-track and clock components from positive to negative for BDS-2 IGSO and MEO. Compared to the moderate correlation of 0.13\(-\)0.41 between orbit radial component and clock errors of GEO or IGSO, both BDS-2 and -3 MEO satellites show the least averaging correlations of no more than 0.1. The global average user range error (URE) of BDS-3 (BDS-2) is approximately 0.6 m (1.0 m), which is dominated by satellite-dependent clock bias. When these biases are removed from the clock residuals, the URE can be reduced by 50% and 15% for BDS-3 and BDS-2, respectively.

北斗卫星导航系统（BDS）正在经历从区域（BDS-2）向全球（BDS-3）服务能力的转变，BDS-2和BDS-3共同提供主要导航服务。使用国际全球导航卫星系统 (GNSS) 服务 (IGS) 自 2016 年 1 月以来大约 5 年的星历表和武汉大学 (WHU) 的精确产品，我们提供了空间信号 (SIS) 误差 (SISE) 评估) 用于 BDS-2 和 BDS-3 广播星历。由于北斗三号卫星采用新的星间链路（ISL），数据、星历（AODE）和数据、时钟（AODC）年龄小于一小时的百分比分别为96.48%和95.78%，分别与 BDS-2 的 72.16% 和 79.25% 相比。ISL 还改进了广播轨道性能。BDS-2 和 BDS-3 的地球同步地球轨道（GEO）广播轨道的 3D 均方根误差（RMSE）分别为 6.89 m 和 2.45 m，而倾斜地球同步轨道的 3D 均方根误差（RMSE）分别为 2.04 m 和 0.75 m（ IGSO) 和 1.99 m 和 0.47 m 用于中地球轨道 (MEO)。在这个贡献中发现，与其他导航系统（即 GPS、GLONASS 和伽利略）相比，BDS-2 和 BDS-3 地球参考系轨道实现中隐含的方向更分散。考虑到自转参数的估计，北斗三号（北斗二号）的非径向轨道误差可改善约0.2米（0.1米）。发现卫星激光测距（SLR）残差中的线性模式以北斗广播轨道为特征，轨道模型可能需要改进。在广播时钟误差方面，BDS-2 和 BDS-3 的标准偏差 (SD) 的平均值分别为 0.4 m 和 0.2 m。然而，在 BDS-3 卫星上也观察到了显着的依赖于卫星的非零时钟偏差，使用差分码偏差 (DCB) 产品可以部分减少这种偏差。当星历参考点从天线切换到质心时，BDS-2 GEO卫星的轨道径向分量和时钟误差之间的相关性从-0.30变化到0.31。同时，参考点切换导致 BDS-2 IGSO 和 MEO 的沿轨道和时钟分量之间的相关性从正变为负。与 0.13 的中等相关性相比 BDS-2 和 BDS-3 分别为 2 m。然而，在 BDS-3 卫星上也观察到了显着的依赖于卫星的非零时钟偏差，使用差分码偏差 (DCB) 产品可以部分减少这种偏差。当星历参考点从天线切换到质心时，BDS-2 GEO卫星的轨道径向分量和时钟误差之间的相关性从-0.30变化到0.31。同时，参考点切换导致 BDS-2 IGSO 和 MEO 的沿轨道和时钟分量之间的相关性从正变为负。与 0.13 的中等相关性相比 BDS-2 和 BDS-3 分别为 2 m。然而，在 BDS-3 卫星上也观察到了显着的依赖于卫星的非零时钟偏差，使用差分码偏差 (DCB) 产品可以部分减少这种偏差。当星历参考点从天线切换到质心时，BDS-2 GEO卫星的轨道径向分量和时钟误差之间的相关性从-0.30变化到0.31。同时，参考点切换导致 BDS-2 IGSO 和 MEO 的沿轨道和时钟分量之间的相关性从正变为负。与 0.13 的中等相关性相比 当星历参考点从天线切换到质心时，BDS-2 GEO卫星的轨道径向分量和时钟误差之间的相关性从-0.30变化到0.31。同时，参考点切换导致 BDS-2 IGSO 和 MEO 的沿轨道和时钟分量之间的相关性从正变为负。与 0.13 的中等相关性相比 当星历参考点从天线切换到质心时，BDS-2 GEO卫星的轨道径向分量和时钟误差之间的相关性从-0.30变化到0.31。同时，参考点切换导致 BDS-2 IGSO 和 MEO 的沿轨道和时钟分量之间的相关性从正变为负。与 0.13 的中等相关性相比\(-\) 0.41 轨道径向分量和GEO 或IGSO 的时钟误差之间，BDS-2 和-3 MEO 卫星显示不超过0.1 的最小平均相关性。BDS-3（BDS-2）的全球平均用户距离误差（URE）约为0.6 m（1.0 m），主要受卫星相关时钟偏差的影响。从时钟残差中去除这些偏差后，BDS-3 和 BDS-2 的 URE 可以分别降低 50% 和 15%。