Research On Spectrum Allocation Techology Of Cognitive Radio

With the development of wireless communication technology and the increase in the demandof communication service, the spectrum resource becomes nervous hindering the development ofwireless communication business. So how to improve the spectrum utilization dynamically andefficiently becomes the focus of people who pay attention to. In order to solve the problem, thecognitive radio arises at the historic moment. Easing the tension of spectrum resource andadvancing the system utility, cognitive radio spectrum allocation is the key of cognitive radiotechnology, playing an important role in the cognitive radio system.This paper not only makes a study of dynamic spectrum allocation algorithm in the graphcoloring model of cognitive radio network，but also puts forward the improved algorithms based onthe existing algorithms.Firstly，this paper describes the cognitive radio, cites the spectrum allocation model, and thenconducts further studies on the basis of graph coloring model, proposes the advanced spectrumallocation algorithm based on the users’ requirement. According to the simulation results，comparedwith existing algorithms, this algorithm has a better performance. Then it also introduces thequantum genetic algorithm in the graph coloring spectrum allocation model. The paper highlightsthe method of the encoding feasibility, principle of the quantum genetic algorithm and some mainoperations. Making full use of spectral characteristics of cognitive radio network, citing thedynamic step length in adjustment of angle of quantum gate, quantum crossover and mutationoperation, an improved quantum genetic algorithm is proposed. More importantly，the simulationresults show that the new algorithm can achieve more effectiveness of the system, having a betterperformance than previous algorithms.