A broadband signal radio communication device which is capable of transmitting audio signals in a frequency band wider than a normal transmission band from 0 to 4 kHz in a radio system such as Bluetooth which employs a radio communication link through weak radiowaves. A plurality of channels are set between the same master and slave out of three channels maximally available on a synchronous connection oriented (SCO) communication link. The band of a transmitted audio signal is divided into a plurality of sub-bands each having a bandwidth of 4 kHz using a sub-band analysis approach, and the signals in the respective bands are assigned to associated SCO links for transmission. On the reception side, the signals in the respective bands, received through the plurality of SCO links, are synthesized by a sub-band synthesis approach to reproduce an audio signal having the original frequency band.