Method for controlling signal power level to control contention beween mobile terminals, and signal power level controller in orthogonal frequency division multiplexing system

A mobile terminal accessed to a base station in an orthogonal frequency division multiplexing access system, the mobile terminal comprising:

• a signal power level controller device, the signal power level controller comprising:
• a received power obtaining unit for obtaining a received power level of received cell broadcasting information when the mobile terminal receives the cell broadcasting information from the base station;
• a transmission power information obtaining unit for obtaining base station transmission power information included in the cell broadcasting information wherein the transmission power information is power information of the cell broadcasting information when the cell broadcasting information is transmitted from the base station to the mobile terminal;
• and
• a transmission power determining unit for determining a power level applied to transmit a signal from the mobile terminal to the base station, based on the obtained received power level and the base station transmission power information.