认知星地混合网络中基于能效最大化的最优功率控制方法

Optimal Power Control based on Energy-Efficiency Maximization in Cognitive Satellite-Terrestrial Networks

在认知星地混合网络中,当卫星系统作为主用户时,为了保证卫星用户正常的通信质量,在下行链路中必须要对地面次级用户进行必要的功率控制。考虑到绿色通信场景,选择次级用户的能量效率作为优化目标,提出了两种最优功率控制方法。两种方法分别使用了平均发射功率约束和峰值发射功率约束,而为了寻找最优能效值,提出了一种新的迭代搜索算法。仿真结果证明,所提搜索算法具有有效性和高效性,且干扰链路信道条件越好,次级用户性能越差。

In the cognitive satellite-terrestrial networks,when satellite system is the primary user,power control is necessary for terrestrial secondary user,thus to guarantee the communication quality of satellite user in downlink case.In consideration of the green communication scene and by choosing the energy efficiency of secondary users as the optimization target,two optimal power control methods are proposed.The two methods use the average emission power constraints and the peak emission power constraints respectively.In order to find the optimal energy efficiency value,a new iterative search algorithm is presented.The simulation results indicate that the proposed algorithm is effective and efficient,and the better the channel condition of the interference link,the worse the performance of the secondary user.