Data transmission mechanism of time-division duplex communication system supporting different radio communication standards

A method of communication device (100) which is capable of respectively supporting different radio communication standards during different time periods, the communication device (100) comprises a first communication circuit (105) configured for supporting a first radio communication standard and a second communication circuit (110) configured for supporting a second radio communication standard different from the first radio communication standard. The method includes: using the first communication circuit (105) to send time information to a peer communication circuit (101, 101A) for notifying the peer communication circuit (100, 101A) of when the first communication circuit will switch to a radio inactive mode.