Test and Analysis of the Influence of Lake Water Obstacle on the Near-field Timing Signal of BPC

Abstract

The lake water environment is a common and complex scenario for the application of radio time synchronization. When the timing signal enters lake water, signal strength attenuation and phase shift occur, which greatly affect time service performance. By comparing the differences in signal field strength and time difference at the same distance from the transmitting station along two different direction paths – one through soil and the other through lake water – the influence of the freshwater lake transmission medium on the propagation of BPC timing signals within the ground wave range was analyzed. This paper uses the BPC timing signal as an example to describe the propagation mode and attenuation characteristics of the signal when it enters the lake water environment, and establishes a BPC field strength and time difference measurement system to analyze possible field strength and time difference variation laws of the BPC timing signal at different propagation distances in lake water. Studies show that at a distance of 25 km from the transmitting station, when the signal passes through lake water, the field strength attenuation is approximately 0.24 dBμV/m and the time difference increases by approximately 8.04 μs. At a distance of 138 km from the transmitting station, when the signal passes through lake water, the field strength attenuation is approximately 0.6 dBμV/m and the time difference increases by approximately 14.1 μs.