GPS Satellite Clock Bias Prediction Based on Exponential Smoothing Method

A new method of GPS satellite clock bias prediction based on exponential smoothing method (ESM) is presented in this paper. This new method can develop the prediction model successfully by using a small amount of data and has the advantages of easier calculation and convenience in operation. And the good results can still be acquired by this new method when the relevant historical data are absent or the changing trend of data is unobvious or unstable. By contrast with the quadratic polynomial model (QPM) and gray system model (GM) which are usually used in GPS satellite clock bias prediction, the calculating and analyzing results indicated that the ESM can be used in the medium-term and short-term prediction of GPS satellite clock bias and the prediction precision can reach up to nanosecond (ns) level. The prediction results of ESM are better than QPM but on the same level with GM when a small amount of data is used to establish the prediction model. And in the mean time, the ESM can also be used in the long-term prediction of GPS satellite clock bias and the prediction precision can reach up to microsecond (μs) level which is on the same level with GM.