Highly flexible active notch filter for Cognitive Radio

Nowadays, many wireless communication devices should share the precious radio-frequency bandwidths. In order to get the most of the available spectrum, Cognitive Radio (CR) are recently introduced to allow better spectrum management for newly standardized radio communication systems. An advanced multistandard terminal device may cover several communication standards. The system of such device should be highly flexible to dynamically and autonomously adjust its radio operating parameters. Moreover, the reduction of interference among radio communication systems is needed to allow the coexistence of different standards in the same device. In this paper, a new concept and system architecture to reach our goal are proposed and discussed. Our ultimate goal aims to ensure the coexistence of different standards in a CR mobile terminal.