A Method of Obtaining High Precision Propagation Delay for BPL Timing Signal

Due to the diversity and complexity of the geography and weather, the propagation delay variation of long wave timing signal also shows a certain different when it propagates along the earth's surface, How to obtain precise propagation delay is always a bottleneck that restricts the realization of the high precision timing service in the long wave system. Based on the measured data of propagation delay, the relationship between the propagation delay variation of the user group received signal is analyzed, the distance between the user is 100 kilometers. It is founded that when the signal transmission path is similar and the weather is similar on the path, the variation of propagation delay of the signal is basically the same with time. In view of the above analysis, a method for obtaining the high precision propagation delay is proposed, and the method is verified by the actual measurement data. The results show that the method compared with the traditional method can get high precision propagation delay and can reflect the real-time change of propagation delay. It is proved that the proposed method can further improve the timing precision of long wave system, and lay a solid foundation for the study of differential timing technology of long wave.