The Research of Non-cooperative Power Control Method Based on Fairness and User Selection Strategy in Cognitive Radio Networks

When studying the power control problem of cognitive radio based on non-cooperative game theory, most scholars pay more attention to constraints such as interference, signal-to-noise ratio of secondary users, primary user interference threshold and so on. Optimization objectives focus on system throughput, system energy consumption, convergence rate, etc. The fairness problem caused by secondary users in order to increase system throughput is ignored, and the research on whether all the secondary users participate in the communication meets the communication conditions is in blank state. Based on the fairness problem, an automatic power control game algorithm based on cost function is proposed in this paper. When the cost function is designed, the influence of distance on channel gain is fully considered, and the penalty mechanism is introduced by adjusting the weight adaptively. The interference between users is reduced, and the near-far effect caused by different user location is effectively overcome. In order to solve the problem of whether the secondary users meet the communication conditions, a sub-user selection strategy is proposed to accurately control the secondary users who participate in the communication, thus avoiding the hidden danger to the stability of the system caused by the users who do not meet the communication conditions. The necessity and practical value of the user selection strategy are verified by simulation. At the same time, the performance of the proposed algorithm in convergence speed and energy saving is also highlighted.