US Patent 8233928 System and method for managing spectrum allocation

Disclosed are techniques for managing situations where spectrum use by one party is preempted by spectrum needs of another party. A revocation may be sent from a spectrum management system to secondary radio systems that are impacted by the presence of priority radio system. Remedial action may be taken if an acknowledgement of the revocation message is not received from a secondary radio system. Also, the secondary radio systems may transmit keep-alive messages to monitor operation of the communication pathway for the revocation messages.