Dynamic Frequency Broker and Cognitive Radio

Traditional frequency allocation and assignment are relatively slow processes that are not so well suited for satisfying and exploiting dynamic spectrum needs of various communication and broadcast systems. This leads to poor average utilization of the spectrum, yet with the demand for assigned spectrum in some bands and locations exceeding availability. Cognitive radio (CR) attempts to increase the spectrum utilization by sensing and reusing available spectrum bands, e.g. in the 802.22 standard the CR system attempts to reuse spectrum bands allocated to TV transmitters.