COGNITIVE RADIO SYSTEM FOR DYNAMIC ALLOCATION OF UHF BAND CHANNELS BASED ON 802.11AF AND USING THE ENERGY DETECTION ALGORITHM

This paper describes the development of a cognitive radio system through software-defined approach, using universal software peripheral (USRP) devices and digital television equipment for communication in UHF band. The algorithm was developed LabVIEW is based on energy detection, where average power video carrier tv signal calculated compared with established threshold value. As result free channels are determined assigned transmission an Secondary User (SU), which will synchronize receiver same working frequency. For evaluation performance tests, DTT transmitter were used, simulate Primary (PU), when detects it, it releases frequency use SU assigns another to guarantee continuity trasmission service. Tests carried out determine efficiency system, taking into account response time its allow coexistence systems within spectrum. System times measured, being 1.07 s 41.47 shortest longest respectively, change order avoid interference PU. Using sampling techniques, 21.33 s, proving that efficient environments high services not sensitive latency.