To select a communication channel suitable for transmission using an operating channel, when communications such as transmission of data (video data etc.) requiring band guarantee for continuing occupancy of a communication channel in the state of almost monopoly during a comparatively long period (for example, reproducing of video image etc.) are conducted on another channel and even when the communications are conducted on the operating channel.
A noise information update processing portion 22 is stored in a radio field intensity/channel memory portion 21, and updates a noise information indicative of a level of a steady radio field intensity for each idle channel. On the other hand, an operating channel decision unit 41 of an operating channel selection processing portion 23 selects a candidate of an operating channel, based on usage situation of each channel. If a plurality of candidates are selected, the selection result is passed to a comparison portion 42 to compare the noise information of each channel and determine the operating channel based on the result of the comparison.
Ryuichi Kijima
Ichiro Kaneko