Patent ID: 8155068

Claim:
A communication system in which communication is performed between a mobile machine and a base-station apparatus by using a plurality of information transmission channels with different frequency bands, the mobile machine comprising: a frequency-variation measuring unit that measures, based on a signal transmitted from the base-station apparatus, a frequency variation, which is a variation in signal strength of the signal with respect to a change in frequency; a time-variation measuring unit that measures, based on the signal transmitted from the base-station apparatus, a time variation, which is a variation in signal strength of the signal with respect to a lapse of time; and a channel allocation determining unit that determines to allocate adjacent sub-channels whose frequency bands are adjacent to each other to the mobile machine when the frequency variation measured by the frequency-variation measuring unit is larger than a predetermined frequency-variation threshold and the time variation measured by the time-variation measuring unit is smaller than a predetermined time-variation threshold, and determines to allocate distributed sub-channels whose frequency bands are distributed to the mobile machine when the frequency variation is equal to or smaller than the frequency-variation threshold or the time variation is equal to or larger than the time-variation threshold; and the base-station apparatus comprising a channel allocating unit that allocates either the adjacent sub-channels or the distributed sub-channels to the mobile machine based on the sub-channel determined by the channel allocation determining unit.