Under a multi-cell radio communication environment where connection between cells or TDMA frame synchronization is not established, a mobile station carries out an adjacent cell search under low power consumption. Adjacent cell information acquired through search by the mobile station is managed centered on a base station and may be provided by the base station as adjacent cell information, when the mobile station carries out the adjacent cell search. The adjacent cell information includes, for example, a TDMA frame offset between cells so that the mobile station receives a broadcast channel of the adjacent cell at appropriate timing based on the adjacent cell information and therefore does not need to perform unnecessary reception operation in the event of a handoff.