后向散射辅助无线供能网络中的节点间高吞吐量通信方案

High-Throughput Communication Scheme Between Nodes in Backscatter Communication Assisted Wireless Powered Networks

本文研究后向散射辅助无线供能网络中两个边缘节点到一个中继节点的信息传输,节点可工作于后向散射模式和主动通信模式。引入后向散射该辅助功能有助于节点吞吐量提高,但也使通信方案设计更加复杂。提出了由节点后向散射/能量传输阶段和节点主动通信阶段构成的方案。接着,将最大化总吞吐量问题建模为非线性优化问题,并证明其凸特性。最后,基于后向散射时长与节点能量捕获时长阈值的关系,将该问题分解为多个仅需优化后向散射时长的子问题,并设计高效的两层黄金分割搜索算法来求解子问题。基于子问题的最优解来得到原问题的最优解。仿真结果表明,与纯主动通信方案和纯后向散射通信方案比,所提出的方案能有效地提高吞吐量。

This paper studies the data transmission from two edge nodes to one relay node in the backscatter assisted wireless powered network. The nodes can work in backscatter mode and active communication mode. The use of backscattering can improve the node throughput,but it also makes the communication scheme design more complex. The scheme consisting of backscattering/energy transmission phase and active communication phase is proposed. Then,the problem of maximizing total throughput is modeled as a nonlinear optimization problem and its convexity is proved. Finally,based on the relationship between the backscatter durations and the energy harvesting duration thresholds of the edge nodes,the problem is decomposed into several subproblems that only need to optimize the backscatter duration,and an efficient two-layer golden section search algorithm is designed to solve the subproblems. The optimal solution of the original problem is obtained based on the optimal solutions of the subproblems. Simulation results show that,compared with pure active communication scheme and pure backscatter communication scheme,the proposed scheme can effectively improve the throughput.