In this paper, we investigate and analyze full-duplex-based backscatter communications with multiple backscatter devices (BDs). Different from previous works where only the energy from the energy source is harvested, BDs are also allowed to harvest energy from previous BDs by recycling the backscattering energy. Our objective is to maximize the total energy efficiency (EE) of the system via joint time scheduling, beamforming design, and reflection coefficient (RC) adjustment while satisfying the constraints on the total time, the transmit energy consumption, the circuit energy consumption and the achievable throughput for each BD by taking the causality and the non-linearity of energy harvesting into account. To deal with this intractable non-convex problem, we reformulate the problem by utilizing the Dinkelbach's method. Subsequently, an alternative iterative algorithm is designed to solve it. Simulation results show that the proposed algorithm achieves a much better EE than the benchmark algorithms.
翻译:在本文中,我们调查并分析与多个反向散射装置(BDs)的全双倍反向散射通信。 不同于以往只从能源来源中获取能源的工程,BDs也可以通过回收后向散射能源从以前的BDs中获取能源。 我们的目标是通过联合时间安排、波形设计和反射系数调整,最大限度地提高系统的总能源效率,同时满足总时间的限制,传输能源消耗、电路能源消耗和每个BD的可实现的吞吐量,同时考虑到能源采集的因果关系和非线性。 要解决这个棘手的非康韦克斯问题,我们用Dinkelbach的方法重新配置问题。 随后,将设计出一种替代的迭代算法来解决它。 模拟结果显示,提议的算法比基准算法更符合EE。