Comparison of Multi-GNSS Time and Frequency Transfer Performance Using Overlap-Frequency Observations

The modernized GPS, Galileo, and BeiDou global navigation satellite system (BDS3) offers new potential for time transfer using overlap-frequency (L1/E1/B1, L5/E5a/B2a) observations. To assess the performance of frequency with observations BDS3, mathematical models single- dual-frequency carrier-phase (CP) technique are discussed presented. For single-frequency CP model, three-day average RMS values L5/E5a/B2a clock difference series were 0.218 ns Galileo 0.263 which improvements 36.2% 43.9% BDS3 when compared L1/E1/B1 solution at BRUX–PTBB. hydrogen–cesium link BRUX–KIRU, 0.490 0.608 improving by 6.4% 12.5% solution. stability BRUX–PTBB 3.54 × 10−12 2.20 2.69 21.0%, 45.1%, 52.3%, respectively, BRUX–KIRU link, 4.2%, 30.5%, 36.1%, respectively.