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The paper presents a method by sliding window to find an optimal satellite maneuvering time with analyzing the change of constellation geometry at different time.Navigation satellites not only broadcast the signals,the orbits and clock corrections etc.,but also keep an in-view constellation,which are the factors affecting users to calculate position.Effected by orbit perturbations,the satellites will gradually deviate from the designed orbit position after a period of time.For maintaining the constellation geometry,the satellite maneuver must be implemented.But for the satellite navigation system,the maneuvering satellite will broadcast the declined ephemeris,because the satellite position in ephemeris is not consistent with the actual position.So the satellite will be set to be flagged "Don Use" through the ground control system.Thus the number of available satellites will reduce.Especially for the regional constellation,such as BDS (Beidou satellite navigation system),the change of position dilution of precision (PDOP) will affect the users service accuracy.Through analyze of the PDOP value variation on the designated area,the paper puts forward a slide window method of optimal maneuver time selection to reduce the influence.The BDS satellite navigation system has been analyzed and verified the feasibility.The results show that this method can effectively reduce the satellite maneuver bringing to the system services.