反向散射通信辅助的认知无线能量通信网络的时间分配研究

Time Allocation Optimization in Backscatter Assisted Cognitive Wireless Powered Communication Networks

为了改善次发射机的性能,本文在衬底式(Underlay)认知无线能量通信网络(Cognitive Wireless Powered Communication Networks,CWPCNs)中提出了一种新的网络模型,该网络含有一个主发射机和两个由次发射机和次接收机组成的次用户对。次发射机可工作在反向散射通信(Backscatter Communication,Back Com)和收集再传输(Harvest-then-transmit,HTT)两种协议下。针对提高次网络的系统容量,根据收集的能量是否可以驱动次发射机工作,本文考虑了三种场景并针对每种场景设计了最优的时间分配方案。仿真结果表明,相比于单独利用BackCom或HTT协议以及协作式CWPCN,本文提出的新方法性能更佳。

In this paper, we study an underlay cognitive wireless powered communication network （CWPCN）. In this model, there are a primary transmitter and two secondary user pairs, each of which contains a secondary transmitter and a secondary receiver. The secondary transmitter can work in both backscatter communication （BackCom） protocol and harvest- then-transmit （HTT） protocol. To maximize the system throughput of the secondary network, we investigate three cases depending on whether the harvested energy can meet the circuit power consumption of secondary users. For each case, the optimal time allocation policy is derived. Simulation results show that the performance for the proposed model in this paper outperforms that of the traditional models and cooperation CWPCN.