Patent ID: 8780751

Claim:
A communication terminal that calculates the communication quality of a signal transmitted from a radio base station, for each of multiple subbands into which a system bandwidth is divided, comprising: a determining unit that determines, based on the number of resource blocks, as the unit of radio resource, in the entire system band, and based on the number of resource blocks for each of the subbands, designated in accordance with the number of resource blocks in the entire system band in advance, whether a small band or a subband formed of a lower number of resource blocks than the number of resource blocks for each of the subbands is present; a noise power calculator that calculates noise power of the signal for each of the subbands, using reference signals included in the signal transmitted from the radio base station; a signal power calculator that calculates signal power of the signal for each of subbands, using the reference signals and the noise power calculated by the noise power calculator; a channel capacity calculator that calculates channel capacity for each of the subbands, based on the noise power and the signal power; and, a CQI transmitter that transmits CQI (Channel Quality Information) to the radio base station, based on the channel capacity, wherein the noise power calculator, when the determining unit determines that the small subband is present, calculates the noise power as combined noise power, using the reference signals included in the small subband and the adjacent subband next to the small subband, the signal power calculator, when the determining unit determines that the small subband is present, calculates the signal power as combined signal power, using the reference signals included in the small subband and the adjacent subband next to the small subband and the combined noise power, and the channel capacity calculator calculates combined channel capacity based on the combined noise power and the combined signal power, and calculates channel capacity in the small subband based on the combined channel capacity and the channel capacity calculated in the adjacent subband.