Abstract:
Aiming at the instability of reference in time delay calibration of high-precision GNSS time-frequency transfer receiver, a real-time cross-ratio and weighted average method based on multiple references is designed to suppress the influence of time-varying reference anomalies, improve the timeliness of calibration work and ensure the accuracy and reliability of calibration results. Three GNSS time transfer receivers maintained by the National Institute of Metrology were selected as references for experimental verification. The preliminary results confirm the effectiveness of the improved method: to a certain extent, the calibration deviation caused by random fluctuations of a single reference is suppressed; Compared with traditional methods, the calibration efficiency is increased by ~55%.