摘要
将中继协作与认知无线电技术相结合是提高频谱资源利用效率和减小系统功率消耗的有效方法。为此,在认知用户端之间不存在直接链路、中继用户工作在放大转发方式以及认知用户和中继发送功率都受限的场景下,对认知无线电中继协作系统中的功率分配问题进行探讨。利用KKT条件和次梯度法求解优化问题,提出一种最优化功率分配算法。该算法既能保证授权用户平均通信质量和最差通信质量不受影响,又能使认知用户的通信容量达到最大。在瑞利衰落信道下对该算法进行数值仿真,结果验证了其正确性。
Combining relay cooperation with Cognitive Radio( CR) technology is one of the effective ways to improve the utilize efficiency of spectrum resources and reduce power consumption. In the context of no direct link between cognitive users’ ends,relay’ s working in Amplify-and-Forward( AF) mode,and limitation of cognitive users and relay’ s transmitted power,this paper discusses the power allocation in relay cooperative CR systems. Adopting KKT condition and sub-gradient method to solve the optimization problem, an optimal power allocation algorithm is proposed. This algorithm not only can ensure authorized users’ average communication quality and worst communication quality are not affected,but also can maximize cognitive users’ communication capacity. Meanwhile,in the Rayleigh fading channel, numerical simulation of the proposed algorithm verifies itself further.
出处
《计算机工程》
CAS
CSCD
北大核心
2015年第5期93-96,101,共5页
Computer Engineering
关键词
认知无线电
中继协同通信
功率分配
凸优化
对偶分解法
次梯度法
KKT条件
Cognitive Radio ( CR )
relay cooperative communication
power allocation
convex optimization
dualdecomposition method
sub-gradient method
KKT condition