Patent ID: 8139662

Claim:
A mobile station apparatus comprising: a calculating unit configured to calculate a channel quality indicator (CQI) value for each of groups, into which subcarriers that are consecutive in a frequency domain are divided in a predefined unit of a time domain, the CQI value representing channel quality according to a first step size, by which a range of the CQI value is divided; a generating unit configured to generate feedback information based on the calculated CQI value for each of the groups; and a transmitting unit configured to transmit the feedback information, wherein: said calculating unit calculates a differential value for each of the groups, the differential value being a difference of the calculated CQI value with respect to a single CQI value which represents channel quality for all of the groups, and transforms the differential value according to a second step size, which includes a step size greater than the first step size and by which a range of the difference is divided, and said generating unit generates the feedback information forming a data sequence, in which the single CQI value is positioned at the beginning and the differential values for the groups are positioned after the single CQI value in order of increasing frequency or decreasing frequency.