Patent ID: 8213407

Claim:
A wireless communication system comprising: a mobile station; a plurality of base stations which are capable of performing wireless communication with the mobile station and which include a micro cell base station configuring a micro cell and a macro cell base station configuring a macro cell larger than the micro cell; and a control server which controls handover between the plurality of base stations, wherein each of the base stations includes an adjustment signal transmission unit which transmits an adjustment signal for advancing or delaying data transmission timing in the mobile station in order to adjust timing for receiving data from the mobile station to a desired timing, wherein the mobile station includes a timing adjustment unit which receives the adjustment signal and adjusts the data transmission timing, the wireless communication system further comprising: a bias amount calculation unit which calculates a bias amount of the adjustment signal; a carrier sense performing unit which, if the bias amount is a first threshold value or higher and if a base station, with which the mobile station is performing wireless communication, is a micro cell base station, performs carrier sense for changing over into connection with a macro cell base station; and a handover request unit which selects one macro cell base station from one or more of macro cell base stations extracted through the carrier sense and which requests handover to the selected macro cell base station, to the control server, wherein the control server includes: a handover performing unit which performs handover from the micro cell base station which is performing wireless communication with the mobile station, to the selected macro cell base station, in response to the handover request.