BDS-3/GNSS Multi-frequency PPP Rapid Ambiguity Resolution

The four available civil frequencies of BDS-3 provide strong support for multi-frequency multi-system PPP-AR. It has been shown that multi-frequency improves the PPP-AR positioning performance of BDS-3/GNSS significantly, but most of the IGS station 30 s sampling rate observations are used to evaluate the positioning performance, while the high sampling rate is closer to the actual application scenario. To fill this gap, the multi-frequency multi-system BIAS product of CNES is used, combined with the 1 s sampling rate observations of the European EUREF station, to verify the multi-frequency BDS-3/GNSS is used to verify the possibility of achieving 1 s ambiguity resolution. The multi-frequency and multi-system single-epoch PPP-WAR is performed for smart driving applications with sub-metre positioning requirements, and the necessary conditions to meet the accuracy are analysed. Therefore, this paper analyses the stability differences between CNES BIAS phase fractional deviation product systems, between satellites and between frequencies; achieves fast convergence of the BDS-3/GNSS full-frequency PPP-AR by optimising the partial ambiguity fixation algorithm, and analyses the contribution of the number of wide lane fixes in the single-epoch PPP-WAR. The results show that the inter-system standard deviation of BIAS products: GPS < Galileo < BDS-3; the BDS-3 four-frequency PPP-AR imitates a dynamic mean convergence time of 15.32 min, with horizen and vertical accuracy of 4.3 cm and 5.3 cm; in the BDS-3/GNSS multi-frequency PPP-AR experiments, fast convergence within 3 min can be achieved with 90% confidence. In the BDS-3/GNSS multi-frequency PPP-AR experiment, the horizen and vertical accuracy can be 2.2 cm and 8.9 cm with 90% confidence, and some samples can be converged with 1 s fixation; in the single-epoch PPP-WAR, the horizen accuracy of 20 cm and vertical accuracy of 30 cm can be achieved when the number of WL fixation reaches 13.