Information sharing method in cognitive radio communication, cognitive radio communication device, and cognitive radio communication system

In a cognitive radio communication device, before a communication link for the cognitive radio communication is established, a control channel which is a common channel which can be used by a plurality of cognitive radio communication devices is detected. By exchanging sensing information and sensing control information among the plurality of radio communication devices using the detected common channel, the information is shared. The plurality of cognitive radio communication devices share the sensing information and the sensing control information, and use the information for determining a channel used for spectrum monitoring and data communication, and the like.