Research On Spectrum Allocation Based On The Improved Quantum Genetic Algorithm In Cognitive Radio Network

The development of radio communication technology leads to the serious shortage ofwireless spectrum. Cognitive radio provides an effective way to solve the problem ofshortage of spectrum resources. With the dynamic spectrum allocation of cognitive radioto replace the traditional statics spectrum allocation, can greatly improve spectrumutilization. Therefore, in cognitive radio system, the idle spectrum resource allocationstrategy research has important theoretical significance and application value.In the field of cognitive radio spectrum allocation, simple quantum genetic algorithmbased on graph theory model has been applied, and achieved certain results. Simplequantum genetic algorithm has defects as slow convergence speed, easy to premature,accuracy is low, so an improved quantum genetic algorithm that bases on cognitive radiospectrum allocation model of graph theory is proposed in this paper.The graph theory model that is used to color-Sensitive graph coloring algorithm andsimple quantum genetic algorithm is mathematical descripted. Based on basic quantumgenetic algorithm, a model for spectrum assignment using the chaotic search quantumgenetic algorithm is proposed to solve the spectrum allocation of cognitive radio. Themodel uses chaotic search method to initialize the population of chromosome coding andupdate strategy for dynamic adjustment of quantum rotating angle and through thevariation of threshold for selective mutation on chromosome and set the new interferenceconstraint rules in spectrum allocation process. The simulation results show that theproposed algorithm has the faster convergence speed and better optimization performancecomparing with the existing algorithm. The results also show that the proposed algorithmcould increase the fairness of the allocation and the utilization of spectrum comparing withthe existing algorithm.