A cognitive radio base station may transmit, for each channel, common control channel information to a plurality of cognitive radio terminals at different points in time, respectively. Accordingly, the cognitive radio base station may receive a channel allocation request from the plurality of cognitive radio terminals receiving the common control channel information and allocate a plurality of channels to the plurality of cognitive radio terminals, respectively, to perform communication. In response to another terminal existing in a corresponding channel, the cognitive radio base station may update the common control channel information and switch to another channel to transmit subsequent common control channel information at, for example, a closest point in time to thereby broadcast the updated common control channel information to the plurality of cognitive radio terminals using the switched channel.