A wireless communication system constituted by a plurality of base stations including non-serving base stations and a serving base station, and a mobile station, each of the plurality of base stations including: means for generating synchronization information to synchronize the mobile station with the base station from a reverse pilot signal received from the mobile station; means for generating reverse propagation quality information from the reverse pilot signal; and means (1005, 1006) for generating a forward control signal including the synchronization information and the reverse propagation quality information, and for transmitting the forward control signal, and the mobile station including: means for generating and transmitting the reverse pilot signal; means for receiving a signal including the forward control signal from each of the plurality of base stations; means (2002, 2004) for extracting the reverse propagation qualities and the synchronization information from the received forward control signals means for selecting an optimum base station as a new serving base station from the plurality of base stations based on the reverse propagation qualities from the plurality of base stations; and means (2005, 2006) for changing a transmission timing of the reverse pilot signal based on the synchronization information extracted from the forward control signal of the selected optimum base station and transmitting the reverse pilot signal when the selected optimum base station is different from the previous serving base station. means for generating synchronization information to synchronize the mobile station with the base station from a reverse pilot signal received from the mobile station; means for generating reverse propagation quality information from the reverse pilot signal; and means (1005, 1006) for generating a forward control signal including the synchronization information and the reverse propagation quality information, and for transmitting the forward control signal, and the mobile station including: means for generating and transmitting the reverse pilot signal; means for receiving a signal including the forward control signal from each of the plurality of base stations; means (2002, 2004) for extracting the reverse propagation qualities and the synchronization information from the received forward control signals means for selecting an optimum base station as a new serving base station from the plurality of base stations based on the reverse propagation qualities from the plurality of base stations; and means (2005, 2006) for changing a transmission timing of the reverse pilot signal based on the synchronization information extracted from the forward control signal of the selected optimum base station and transmitting the reverse pilot signal when the selected optimum base station is different from the previous serving base station. means for generating and transmitting the reverse pilot signal; means for receiving a signal including the forward control signal from each of the plurality of base stations; means (2002, 2004) for extracting the reverse propagation qualities and the synchronization information from the received forward control signals means for selecting an optimum base station as a new serving base station from the plurality of base stations based on the reverse propagation qualities from the plurality of base stations; and means (2005, 2006) for changing a transmission timing of the reverse pilot signal based on the synchronization information extracted from the forward control signal of the selected optimum base station and transmitting the reverse pilot signal when the selected optimum base station is different from the previous serving base station.