基于OFDM的认知无线电系统中功率分配算法  

Power allocation algorithm in OFDM-based cognitive radio systems

作　　者：杨守义[1] 宋延涛[1] 陈泽先[1] 陆彦辉[1] 

机构地区：[1]郑州大学信息工程学院,河南郑州450001

出　　处：《郑州大学学报（工学版）》2011年第5期56-60,共5页Journal of Zhengzhou University（Engineering Science）

基　　金：国家自然科学基金资助项目(60702020)

摘　　要：针对基于正交频分复用(OFDM)的认知无线电系统中,子载波功率分配的最优化算法中出现的迭代运算繁琐、不易实现的问题,提出一种基于幂函数分布的次优化功率分配算法.该算法采用线性约束的凸优化数值运算方法,对认知用户频带内子载波的功率按照幂函数的数值特性依次分配,该算法具有运算速度快、易于实现的特点,并且有效地解决了授权用户受到认知用户频带内子载波带外泄漏功率的干扰问题.通过使用MATLAB建模仿真,结果表明,提出的算法方案在满足授权用户干扰门限的条件下,使得认知用户频带内信道容量能够达到最大化,并且在同样条件下提高了现有功率分配方案的最大传输速率.In cognitive radio system based on orthogonal frequency division multiplexing（OFDM）,the optimized algorithms for sub-carrier power allocation share the problems of complex iterative calculation and difficult realization.In this case,a sub-optimal power allocation algorithm based on power function distribution is proposed,to allocate power of in-band subcarrier of cognitive user according to the numerical characteristics of the power function by using a convex optimization numerical method under linear constraint.This algorithm has the advantages of fast calculation speed and easy for realization,and reduces the interference for the authorized user brought by the power leakage of the in-band subcarrier of cognitive user appears in the out-of-band.MATLAB simulation results show that the proposed scheme maximized the in-band channel capacity of the cognitive user under the interference threshold of authorized user;meanwhile,the maximum transmission rate of the existing power allocation scheme is increased within the same condition.

关 键 词：正交频分复用 认知无线电 功率分配 凸优化 

分 类 号：TN914[电子电信—通信与信息系统]