Study on PPP Time Comparison Based on BeiDou-3 New Signal

The Chinese BeiDou Navigation Satellite System (BDS-3) has completed the network construction and begun to provide high-precision Positioning, Navigation, and Timing (PNT) services for users all over the world. In this paper, we study the Precision Point Positioning (PPP) time comparison based on the BDS-3 new signal. The data presented in this paper includes the observation data from the National Time Service Center of Chinese Academy of the Sciences (NTSC) and the Electronics Academy of Sciences in Czech Republic (TP), and the precise product data released by the International GNSS Service (IGS), which includes the high-precision clock and orbit products. The results show that the multipath noise of the BDS-3 new signal (B1C and B2a) is less than that of the Asia-Pacific region BDS-2 (B1I and B2I), and the standard deviation (STD) of the multipath noise of B2a is the least. When the BDS-3 PPP is applied to the common clock short-baseline time comparison, the standard deviations of the BDS-3 and BDS-2 signals are 0.0296 ns and 0.0341 ns, respectively, the standard deviation of BDS-3 is smaller than that of BDS-2, and therefore the short-baseline time comparison performance of BDS-3 PPP is better than that of BDS-2, the standard deviation of BDS-3 PPP has increased by 13.19% compared with BDS-2. For long-baseline time comparisons between UTC (NTSC) and UTC (TP), the results based on the BDS-3 single system, or BDS-3 with other navigation system fusion PPP time comparison, follow the same trend as the results released by the International Bureau of Weights and Measures (BIPM). The residual standard deviations relative to the BIPM are 0.7039 ns and 0.2994 ns respectively. The stability of the BDS-3 new signal PPP and multi-GNSS fusion PPP time comparison has the same magnitude as the BIPM. As a result, with the completion of BDS-3, the high-precision time comparison based on BDS-3 expected to offer better services for users. The experimental results demonstrate that BDS-3 could be used to calculate the Coordinated Universal Time (UTC) in the future.