Patent ID: 8068839

Claim:
A mobile radio communication system in which a plurality of base station apparatuses communicate with at least one mobile station while they perform a handover operation, characterized in that each base station apparatus comprises: a base station candidate information generating means for generating handover destination base station candidate information indicating base station candidates each of which can become a handover destination, the base station candidates being acquired on a basis of a position of a mobile station with which each base station apparatus in question is currently communicating or a position of each base station apparatus in question; an effective time information generating means for, when, after a lapse of an integral multiple of a fixed time interval from a time when said mobile station could detect a reference signal which were transmitted at the fixed time intervals from a base station candidate included in said handover destination base station candidate information, said mobile station detects the same base station candidate again, generating effective time information indicating either an effective time during which it is guaranteed that a signal from said base station candidate can be detected, the effective time depending on said base station candidate, or an index for enabling said mobile station to drive said effective time; and a transmitting means for transmitting the generated handover destination base station candidate information and the generated effective time information to said mobile station, and characterized in that said mobile station comprises: a receiving means for receiving said handover destination base station candidate information and said effective time information; a base station detection control means for setting up detection time intervals at which the mobile station detects a signal from a base station candidate which can become the handover destination on a basis of the received effective time information and a movement speed thereof; and a base station detecting means for performing detection of a base station apparatus specified by the received handover destination base station candidate information at the set-up detection time intervals.