基于认知OFDM系统的功率分配算法

在正交频分复用的认知无线电系统中,授权用户会受到认知用户频带内子载波带外功率泄漏的干扰。针对这一问题,提出了一种基于幂函数分布的次优化功率分配方案,通过线性约束的凸优化数值运算,有效降低了最优方案中运算的复杂度。给出了在认知用户发射功率约束条件下的信道吞吐量分析。仿真结果表明,所提出的方案在满足授权用户干扰门限约束条件下,提高了现有功率分配方案的认知用户信道吞吐量。

Power allocation algorithm based on cognitive OFDM systems

In cognitive radio system which was based on the orthogonal frequency division multiplexing,license users are easily attacked by the interference of the power leakage of the in-band subcarrier of cognitive user appears in the out-of-band.To re-solve this problem,this paper presents a suboptimal power allocation scheme based on power function distribution.It effectively re-duces computing complexity of the optimal scheme through convex optimization numerical calculation under linear constraint.Finally,it analyses the channel throughput under the constraints of the cognitive user transmit power.Simulation results show that this scheme improves the channel throughput of the cognitive users comparing with the existing power allocation schemes,meanwhile,it meets the interference threshold constraints of license user.