A system controlling the traffic balance between the paging of incoming calls and a location registration and including a plurality of base and mobile stations and a management server for location information of each mobile station. A set of cells formed by the base stations constitutes a first area group. Each mobile station shifts to a mode periodically receiving signals from the base stations if no signals are transmitted and received for a predetermine period. Each base station forms second to n-th area groups (n≧2), each having an area smaller than that of the first area, to be used when the mobile stations are in idle state. Each mobile station selects the area group to register according to the period in which no packet is received and transmitted, and registers its location while specifying an area within this area group with respect to the server.