ANALYSIS OF DELAY FLUCTUATIONS IN TWO-WAY TIME TRANSFER EARTH STATIONS

摘要

The delay fluctuations in earth stations have become the main source of instability that degrades the accuracy of two-way satellite time and frequency transfer. We had installed a satellite simulator system on an earth station for measuring the variations of signal path delays in the station.The purpose of this paper is to analyze delay variations associated with the environmental temperature. With the data collected over 2 months, we observed that the long-term and short-term temperature variations have contributed different influences to the measured delay value of the earth station. Hence, we propose a method to calculate the related variable by combining the temperature data, and its 1st and 2nd differential values with different weighting coefficients. The result shows a possibility of finding a high correlation between the calculated variable and the delay data. The calculated variable can be used to compensate the delay for their fluctuations.