Apparatus and method for selecting an optimum base station whose transmission power is to be changed

A system comprising:

• a plurality of base stations;
• a plurality of mobile stations wirelessly communicating with the plurality of base stations;
• and
• a controller including:
• a memory configured to store first identification information in association with each of the plurality of base stations, the first identification information identifying locations included in a wireless area that is formed according to transmission power control by each of the plurality of base stations, and
• a processor coupled to the memory, the processor being configured to control, based on parameters indicating wireless communication capability at a target location that is included in a first wireless area formed by a first base station and identified by the first identification information, transmission power of a second base station which forms a second wireless area including the target location.