Research On The Power Control In The Weighted Maxmum In Dependent Set Sprectrum Allocation Algorithmm

Cognitive radio network can improve the utilization of spectrum by using spectrum sharing technology Spectrum allocation is one of the key technologies of cognitive radio networks, graph theory is a common spectrum allocation algorithm. The original spectrum allocation algorithm, despite the introduction of power control techniques, but did not take into account the question of the effectiveness of the node. To solve this issue, we introduce non-cooperative game power control algorithm in spectrum allocation algorithm based on the weighted maximal independent set, effectively solve the problem of utility of nodes.In this paper, a detailed introduction to the knowledge of the spectrum allocation based on weighted maximum independent set, then points out the problems existing in the algorithm, in order to solve the problem in spectrum allocation in the introduction of non cooperative game power control algorithm, Firstly, the utility function and the SINR formula be introduced, and explains the meaning of each part in the formula represents, and then according to the requirements of the feasibility determination of spectrum allocation algorithm, so that SINR of each node is greater than the minimum threshold requirement of the SINR, in this context as far as possible make the utility of each node maximum, and finally make the simulation analysis.Simulation results show that the introduction of non-cooperative game power control algorithm in spectrum allocation algorithm based on the weighted maximal independent set causes the transmit power of the node within a predetermined range increasing a little, but the value of the the utility function of the node increasing a lot than which of the traditional power control algorithm. Then the figure of the simulation can also show that, when the distance between nodes is too large, the emission power will increase a lot.In cognitive radio network transmit power of the nodes over the limit cause interference between the nodes increase and the system performance degrade. To prevent this from happening, in the process of spectrum allocation make the introduction of non-cooperative game based on the cost function power control algorithm to solve the problem that remote nodes in order to ensure communication quality, is to increase their transmission power too large. In general, under the premise of ensuring the reliability of communications, the algorithm we proposed can effectively improve the utility of the node.