Comparison Research of Space Atomic Clock Performance Analyse Methods

Satellite navigation time system is crucial factor to the navigation system performance.As the frequency standard,the atomic clock can give the high accuracy and high stability of the standard frequency signal which can be used to the precise timing,so the atomic clock is widely used in navigation satellites as the frequency standard.The algorithm to calculate the atomic clock frequency stability of Allan variance,overlapping Allan variance,Hadamard variance and overlapping Hadamard variance are expounded and analyzed by simulation.It shows that different GPS satellites have different space satellite clock stability,even to the same type of GPS satellites are different for space satellite clock stability,and GPS BLOCK IIR satellites have better frequency stability.