Study of GPS satellite clock's behaviors and prediction
Qianxin Wang · Cehui kexue · 2010
By intensively analyzing recent years IGS SCE data,the author found that the precision of predicting GPS SCE is obviously dependent on the stability of the individual satellite clock.The most recent GPS satellites(BLOCK IIR and BLOCK IIR-M) are more stable than the former GPS satellites(BLOCK IIA).In this paper,the author easily predicted their next 6 hours SCE with LM and IGS ultra rapid products(URP).However,some of BLOCK IIA satellites clocks are instable.Therefore,the paper further analyzed their residuals and found that its residuals showed periodicity together with randomness.Then it suggested a new model for real-time SCE prediction.This model could predict not only the overall trend of SCE,but also the changing of periodic and random terms.Based on the new model and IGS URP,the SCE predicted precisions better than 0.5ns in real time.