摘要
针对全双工认知无线电网络中频谱利用率不高的问题,文中提出一种通过优化频谱感知中能量检测阈值来提升系统频谱利用率的方法。为了获得最优频谱利用率下的能量检测阈值,建立马尔科夫状态转移模型得到全双工认知无线电单位带宽吞吐量,将频谱利用率问题转化为以单位带宽吞吐量为目标函数、以检测概率为约束条件的多约束非线性规划问题。然后,采用内点罚函数法,以单位带宽吞吐量和约束条件构造增广目标函数,将多约束非线性规划问题转化为无约束问题,通过搜索可行域内部一系列的罚因子,求解罚函数的极值点,从而逼近最优频谱利用率下的能量检测阈值。仿真结果表明,在次级用户处于高传输功率和低信噪比时,优化能量检测阈值后的认知无线电网络单位带宽吞吐量有明显提升。
In allusion to the low spectrum utilization in FD(full-duplex)cognitive radio network,a method that improve the spectrum utilization by optimizing the energy detection threshold in spectrum sensing is proposed. In order to obtain the energy detection threshold under the optimal spectrum utilization,a Markov state transition model is established to obtain the unit bandwidth throughput of FD cognitive radio. The spectrum utilization is transformed into a multi-constraint nonlinear programming with the throughput per unit bandwidth as the objective function and the detection probability as the constraint condition. The internal penalty function method is used to construct the augmented objective function with the throughput and constraint conditions of unit bandwidth. The multi-constraint nonlinear programming is transformed into unconstrained nonlinear programming. The optimal point of penalty function is solved by searching a series of penalty factors within the feasible region,thus approaching the energy detection threshold under the optimal spectrum utilization rate. The simulation results show that when the secondary users are in high transmission power and low SNR(signal-to-noise ratio),the unit bandwidth throughput of the optimized cognitive radio network is improved significantly.
作者
姜海滨
余志勇
杨剑
韩宇宸
JIANG Haibin;YU Zhiyong;YANG Jian;HAN Yuchen(Rocket Force University of Engineering,Xi’an 700025,China)
出处
《现代电子技术》
2022年第18期75-79,共5页
Modern Electronics Technique
基金
国家自然科学基金资助项目(62071481)。
关键词
全双工认知无线电网络
能量检测阈值
频谱感知
自干扰消除
单位带宽吞吐量
内点罚函数
FD cognitive radio network
energy detection threshold
spectrum sensing
self-interference cancellation
unit bandwidth throughput
interior penalty function
