A wireless device comprising: a first radio communication portion configured to effect, using frequency bands selected one after another from among a group of frequency bands, radio communication with a first external communication device; and a second radio communication portion, different from the first radio communication portion, configured to effect radio communication with a second external communication device (11, 12) different from the first external communication device; and characterized in that: the first radio communication portion is configured to use, for transmitting data, transmission slots which do not include vacant slots and consist solely of data slots; a field intensity measuring portion (S200; S400) is provided in the second radio communication portion and is configured to measure a field intensity value for each of a plurality of frequency bands belonging to at least said group of frequency bands while the first radio communication portion continuously transmits data; an excluding portion (S120, S310) is provided in the first radio communication portion and is configured to exclude, from said group of frequency bands, each of said plurality of frequency bands for which the measured field intensity value is higher than a predetermined threshold; and a hopping table preparing portion (S130, S320) is provided in the first radio communication portion for preparing a hopping table for replacing said each of said plurality of frequency bands for which the measured field intensity is higher than the predetermined threshold with another frequency band. a first radio communication portion configured to effect, using frequency bands selected one after another from among a group of frequency bands, radio communication with a first external communication device; and a second radio communication portion, different from the first radio communication portion, configured to effect radio communication with a second external communication device (11, 12) different from the first external communication device; and characterized in that: the first radio communication portion is configured to use, for transmitting data, transmission slots which do not include vacant slots and consist solely of data slots; a field intensity measuring portion (S200; S400) is provided in the second radio communication portion and is configured to measure a field intensity value for each of a plurality of frequency bands belonging to at least said group of frequency bands while the first radio communication portion continuously transmits data; an excluding portion (S120, S310) is provided in the first radio communication portion and is configured to exclude, from said group of frequency bands, each of said plurality of frequency bands for which the measured field intensity value is higher than a predetermined threshold; and a hopping table preparing portion (S130, S320) is provided in the first radio communication portion for preparing a hopping table for replacing said each of said plurality of frequency bands for which the measured field intensity is higher than the predetermined threshold with another frequency band. the first radio communication portion is configured to use, for transmitting data, transmission slots which do not include vacant slots and consist solely of data slots; a field intensity measuring portion (S200; S400) is provided in the second radio communication portion and is configured to measure a field intensity value for each of a plurality of frequency bands belonging to at least said group of frequency bands while the first radio communication portion continuously transmits data; an excluding portion (S120, S310) is provided in the first radio communication portion and is configured to exclude, from said group of frequency bands, each of said plurality of frequency bands for which the measured field intensity value is higher than a predetermined threshold; and a hopping table preparing portion (S130, S320) is provided in the first radio communication portion for preparing a hopping table for replacing said each of said plurality of frequency bands for which the measured field intensity is higher than the predetermined threshold with another frequency band.