Patent ID: 7843887

Claim:
A mobile station apparatus that selects a communicating party in a mobile communication system to which MIMO communication is applied, the mobile station apparatus comprising: a receiving section that receives signals transmitted from a plurality of communicating party candidates; a channel estimation section that performs channel estimation per communicating party candidate using the received signals; a channel capacity calculation section that calculates a determinant of a matrix based on a channel matrix obtained by way of the channel estimation as channel capacity per communicating party candidate; and a selection section that selects a communicating party candidate whose acquired channel capacity is largest as a communicating party, wherein: the channel capacity calculation section, during a wait to communicate, calculates the determinant of the matrix based on the channel matrix as the channel capacity per communicating party candidate, and after communication starts, calculates singular values per path from a result of the channel estimation and takes a number of singular values greater than or equal to a predetermined threshold value, as channel capacity per communicating party candidate.