A source-assisted channel management method in a distributed spectrum cognitive radio wireless network handling a source of multimedia stream data handles a plurality of communicating devices (1, 2, 3) forming a group, and manages channels with no separate controller that is referenced in applicable IEEE standard. The source makes the reservation on behalf of the device group knows traffic schedule, and determines out-of-band channel scanning, back up channel and channel vacation. The method uses a flexible MAC superframe structure and proactively scans for back-up channels which could be used in lieu of the current channel, identifies devices in the group which should vacate a current channel when any one device from the group of communicating devices (1, 2, 3) detects an incumbent, and make a determination as to when the wireless network should vacate the current channel based on said traffic schedule. The method ensures that no interference is caused to existing users and maintains QoS.