Optimal power allocation algorithm in OFDM-based cognitive radio systems
Yantao Song · Journal of Shaanxi University of Technology · 2012
In cognitive radio systems based on orthogonal frequency division multiplexing techniques,the license users suffer from the interference brought by power leaking out with the out-of-band subcarriers′ side-lobes from the in-band subcarrier of cognitive user.This paper introduces power control parameter to adjust the interference power constraint threshold of license user.To get an optimal power allocation scheme,an algorithm is proposed to find out the optimal power allocation scheme for the sub-carriers of cognitive user by means of solving a convex optimization problem.Simulation results show that the proposed power allocation scheme can maximize the capacity of cognitive user under the interference power constraint of license user.