关键词: 卫星钟差, 小波分解, 灰色模型, 混沌时间序列, 一阶加权局域预测

Abstract: In order to improve the accuracy of nonlinear satellite clock bias prediction and reduce the risk of single clock bias prediction model for clock bias prediction,a satellite clock bias prediction algorithm based on combined model is proposed.The algorithm firstly uses db1 wavelet to conduct a 3 layer multiresolution decomposition and single branch reconstruction of satellite clock bias sequences,and obtains a trend component and three detail components.Then the grey prediction model is used to predict the reconstructed trend component and the chaotic time series one-order weighted local prediction method is used to predict the reconstructed detail components.Finally,each component prediction result is added to obtain the total clock bias prediction value.Taking the GPS satellite clock bias data as an example,the maximum absolute error of the algorithm is at least 1.3ns smaller than that of a single gray prediction model in 6-hour clock bias prediction.This combined prediction model can be applied to the prediction of nonlinear satellite clock bias,which can improve the accuracy and reliability of clock bias prediction.

Key words: satellite clock bias, wavelet decomposition, grey model, chaotic time series, one-order weighted local prediction