Patent ID: 8335230

Claim:
A communication device for conducting radio communications with a base station, comprising: a use bandwidth setting unit to set a desired bandwidth; a free bandwidth calculation unit to calculate free bandwidth using full bandwidth used by the base station and bandwidth used to communicate with terminals accommodated in the base station, which are extracted from a header of down link data from the base station, the down link data being transmitted with a regular interval; a determination unit to determine whether the desired bandwidth is equal to or less than the free bandwidth; and a registration unit to register the desired bandwidth in a network in the base station when the desired bandwidth is equal to or less than the free bandwidth, wherein when the down link data is received from the base station, the communication device conducts a synchronization process and a decoding process of the down link data, and wherein when the desired bandwidth is registered, after the synchronization process and the decoding process, the communication device starts an origination sequence including an adjustment control process of transmitting power between the base station and the communication device to communicate with the base station and when the desired bandwidth is not available, the communication device cuts a connection between the communication device and the base station without starting the origination sequence.