Research The Resource Allocation Algorithm Of Cognitive Radio Based On OFDM Technology

Cognitive radio technology, referred to as CR, which presented to solve thespectrum tense problem. Cognitive radio basis of without affecting the normalcommunication on authorized spectrum, and in a certain Way ("opportunity Way")access the authorization frequencies, dynamic use the spectrum resources. It can solvethe existing spectrum resource waste and improve the utilization rate of the spectrumeffectively.Now the spectrum allocation algorithm does not allow multiple CR users accessthe same spectrum, that is to say, one channel at the same time only allow access to auser. Limit the number of CR users access the available spectrum.As to this problem, the main research contents and contributions are as follows:(1) Cognitive radio system based on OFDM was introduced. Mathematical modelwas established, related knowledge and the mathematical formula derivation was usedto analyze the mainly several aspects of the spectrum allocation of cognitive radio basedon OFDM.(2) Classic resource allocation algorithm of the cognitive radio based on OFDMwas explored. The basic principle of the resource allocation algorithm was studied, andseriously studied the resource allocation model and classic algorithm of the cognitiveradio based on OFDM. In the Matlb/Simulink platform, the strengths and weakness ofthe existing allocation algorithm was compared through the computer simulation.(3) Finally, the existing resource allocation algorithm was improved. Resourceallocation algorithm based on the same frequency interference was put forward in viewof the existing algorithms only allow a channel access to a user，and lack of discussionsof the multiple CR users share the same spectrum. In the same time, aimed at thecomplexity of the optimal algorithm, combined with the channel and power allocationalgorithm was discussed. And the results of the simulation verified the improvedalgorithm can improve the spectrum utilization effectively.By analyzing the resource allocation algorithm of cognitive radio based on OFDM,significant conclusions have been drawn, which can improve the spectrum utilization.