Abstract: GPS one-way time transfer is a method to achieve local time and frequency reference calibration and traceability to Coordinated Universal Time (UTC). However, time and frequency transfer performance is impacted due to the change of GPS satellite elevation angle. The basic principle of GPS one-way time transfer is generally described, and the reason why the GPS satellite angle will impact the performance of time and frequency transfer is also analyzed. Furthermore, the assessment method of time and frequency transfer performance is given. Finally, the impact on the performance of time and frequency transfer is tested according to the designed experiment. Moreover, the experiment results are given and analyzed. The experiment results indicate that GPS time and frequency transfer performance will be improved while the number of visible satellite decreases as the increase of satellite elevation mask. In the engineering field, the elevation mask should be set as 25°if the long-term stability is required in time and frequency transfer; while the elevation mask should be set as 5°if just the short-term stability is required.

Key words: Global Positioning System, One-way time transfer, Elevation angle, Transfer performance, Dilution of prcision