A plurality of consecutive frequency bands are used as a broadband and use efficiency thereof is improved. An available-frequency-band-information-list is retained such that the list is categorized into frequency-band-groups, each of the groups is a series of consecutive frequency bands, and a frequency-band-number-width is given to each of the groups. Determining a necessary-frequency-band-number, one group is selected from the groups whose width match the number as a first-type band group, when any of the width of each of the groups does not match the number, one group is selected from the groups whose width are next larger than the number as a frequency band group to be used, and a series of consecutive frequency bands corresponding to the number is selected from the frequency band group to be used as a second-type band group. Communication is controlled so as to use the first-type or the second-type band group.