College of Communication Engineering,Chongqing University,Chongqing 400044,P.R. China;Key Laboratory of Mobile Communication Technology,Chongqing University of Posts and Telecommunications,Chongqing 400065,P.R. China 在期刊界中查找 在百度中查找 在本站中查找
Key Laboratory of Mobile Communication Technology,Chongqing University of Posts and Telecommunications,Chongqing 400065,P.R. China 在期刊界中查找 在百度中查找 在本站中查找
Key Laboratory of Mobile Communication Technology,Chongqing University of Posts and Telecommunications,Chongqing 400065,P.R. China 在期刊界中查找 在百度中查找 在本站中查找
In order to limit the interference caused by cognitive user within the range that primary users can tolerate. The mathematical optimization problem is formulated maximizing cognitive user’s capacity under the interference constraint at the primary receiver．When the signaltonoise ratio of primary user changes according to the communication environment, the cognitive user can adaptively adjust its transmission power according to the interference control factor η. The optimal so1ution to the problem is obtained by utilizing the Lagrange method．A subcarrier and power allocation scheme are proposedamong multiple cognitive users, which is the performance tradeoff between fairness and system capacity. Simulation results show that the proposed scheme can efficiently guarantee the fairness of cognitive users and the capacity performance is close to the optimum.
