Research On Energy Efficiency Based On Graph Spectrum Allocation In Cognitive Radio Network

Wireless cognitive network can take full advantage of the spectrum by spectrum sharing technology and it can be used to effectively solve the shortage of radio spectrum resources. Spectrum allocation technique is one of the key technology in wireless cognitive network and it is usually based on graph spectrum allocation algorithm. In this paper, graph spectrum allocation algorithm is the focus of the research, and the advantages of the maximal independent set based graph coloring spectrum allocation algorithm are used to achieve the power control and energy efficiency optimization, therefore, some innovative achievements have been obtained.Firstly, this paper introduces the key technology of cognitive radio and analyzes the characteristics of the distribution models and the scope of application by comparing the difference between these methods. Secondly, this paper focuses on researching about graph coloring spectrum allocation algorithm, and the advantages or disadvantages has been discussed between the list-coloring algorithm and the color sensitive graph coloring algorithm by simulation. In addition, it describes the method of the spectrum allocation algorithm based on maximal independent set by the form of topology.Although high allocation efficiency of the maximal independent set algorithm, the problem of power control and energy efficiency is not considered, and the improved method is proposed. This paper use technology of power control to ensure cognitive users to meet the minimum SINR on the same channel based on this kind of spectrum allocation algorithm. In addition, the power allocation focuses on the special user, so that the user can achieve energy efficiency optimization and reach the minimum transmission rate. Simulation results demonstrate that the optimized power allocation algorithm has obvious effect on the energy efficiency optimization of the special user, in addition, it can meet the transmission rate of the user and improve the service life at the same time.