| 摘要 |
PROBLEM TO BE SOLVED: To efficiently control usage of a plurality of frequency bands.SOLUTION: Radio communication devices 1, 2 make communications using a plurality of frequency bands. The radio communication device 1, in the case of a procedure of random access, transmits to the radio communication device 2 a control message so as to make communications in a second frequency band different from a first frequency band as a response message corresponding to a preamble message received from the radio communication device 2, using the first frequency band. The radio communication device 2 receives the control message from the radio communication device 1 using the first frequency band, and performs data communication using the second frequency band when the control message corresponds to the preamble message. |
