Patent ID: 7970065

Claim:
A communication apparatus, comprising: an antenna configured to receive and transmit signals; a measuring unit configured to measure a first interference feature quantity indicating a first state of an interference signal in a transmission frequency band from the signals received by the antenna; a determination unit configured to determine from the first interference feature quantity whether the interference signal exists in the transmission frequency band; an acquisition unit configured to acquire, after measurement of the first interference feature quantity, a transmission channel from a second interference feature quantity measured by the measuring unit, the transmission channel corresponding to at least one of a frequency orthogonal to the interference signal, a time orthogonal to the interference signal, a space orthogonal to the interference signal, and a spreading code orthogonal to the interference signal; and a transmission unit configured to perform a first transmission via the antenna using the transmission frequency band when it is determined that no interference signal exists in the transmission frequency band, and to perform a second transmission via the antenna using the transmission channel when it is determined that the interference signal exists in the transmission frequency band, wherein: the acquisition unit stores the transmission channel; the measuring unit measures, after the second transmission, a third interference feature quantity indicating a second state of the interference signal in the transmission frequency band; the determination unit determines from the third interference feature quantity whether the interference signal exists in the transmission frequency band; and the transmission unit performs a next transmission via the antenna when it is determined that the interference signal exists in the transmission frequency band, using a simplified-analysis transmission channel included in the transmission frequency band and acquired by the acquisition unit from a fourth interference feature quantity, the fourth interference feature quantity being acquired by the measuring unit after a determination of the determination unit, the fourth interference feature quantity containing a smaller number of types of data items than the second interference feature quantity.