ON THE INTERNAL STABILITY OF GPS SOLUTIONS

Internal stability is referred to as the uniform asymptotic stability of Kalman filtering solutions, addressing the effects of initial-state errors, observation sample rates, lengths of observation sessions and so on. This paper presents the theory of the internal stability of GP S solutions, including mathematical definitions, properties and theore ms addressing the dependence of internal stability of the filtering so lutions on the controllability and observability of a GPS dynamic posi tioning system. The theory has been applied in analysing the stability performance of different GPS positioning modes, and the actual GPS po sitioning results have demonstrated graphically the asymptotic converg ence of those stable solutions Versus observation tracking time/filter ing time-steps. The internal stability is therefore considered as an i mportant performance criterion to evaluate different GPS positioning s olutions.