Satellite clock error prediction method based on empirical mode decomposition (EMD) model and generalized autoregressive conditional heteroskedasticity (GARCH) model

Abstract

The invention provides a satellite clock error prediction method based on an empirical mode decomposition (EMD) model and a generalized autoregressive conditional heteroskedasticity (GARCH) model, relates to the field of clock error prediction of satellite clock, and solves the problem of difficulty in improving prediction precision because the traditional satellite clock error prediction method lacks prediction of an unstable random term. The method comprises the following steps of: 1, acquiring historical data of clock error, and correcting and pre-processing the data to obtain satellite clock error data; 2, decomposing an empirical mode of the satellite clock error data to obtain a random term part of the satellite clock error data; 3, predicting a trend term of the satellite clock error data, and building a Kalman prediction model to predict the trend term of the satellite clock error data; and 4, predicting a random term of the satellite clock error data, namely, removing the trend term to obtain the random term, predicting the random term by using an auto-regressive and moving average (ARMA) model and the GARCH model, and improving the precision of satellite clock error prediction. The method is used for high-precision time synchronization of a satellite navigation system.

Description

Technical field

[0001] The invention relates to the field of satellite clock clock error prediction. Background technique

[0002] Time synchronization is the foundation and key of a satellite navigation system. The final accuracy of time synchronization depends on the accuracy of satellite clock error prediction. That is, satellite clock error prediction is one of the largest sources of error. Therefore, satellite clock error prediction is the key to satellite navigation systems. One of the technologies.

[0003] Clock error prediction is to use the current existing clock error observation data to obtain the clock error forecast value at a certain time in the future through a certain algorithm. The satellite clock error prediction method based on empirical mode decomposition (EMD) and generalized autoregressive conditional heteroscedasticity (GARCH) model is a high-precision and fast clock error prediction technology. This method uses EMD to decompose satellite clock error data i...

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