The high reflect beamforming gain of the intelligent reflecting surface (IRS) makes it appealing not only for wireless information transmission but also for wireless power transfer. In this letter, we consider an IRS-assisted wireless powered communication network, where a base station (BS) transmits energy to multiple users grouped into multiple clusters in the downlink, and the clustered users transmit information to the BS in the manner of hybrid non-orthogonal multiple access and time division multiple access in the uplink. We investigate optimizing the reflect beamforming of the IRS and the time allocation among the BS's power transfer and different user clusters' information transmission to maximize the throughput of the network, and we propose an efficient algorithm based on the block coordinate ascent, semidefinite relaxation, and sequential rank-one constraint relaxation techniques to solve the resultant problem. Simulation results have verified the effectiveness of the proposed algorithm and have shown the impact of user clustering setup on the throughput performance of the network.

翻译：智能反射表面(IRS)的高反射波束增益使得它不仅吸引无线信息传输,也吸引无线电源传输。在本信中,我们认为一个IRS辅助无线电源通信网络,在这个网络中,一个基地站(BS)将能源传输给多个用户,将其分组成下行的多个集群,而集聚用户则以混合非垂直多重存取和时间分数多重存取的方式将信息传输给BS。我们研究如何优化IRS的反射波以及BS电力传输和不同用户群信息传输之间的时间分配,以最大限度地扩大网络的吞吐量。我们提出基于区块坐标的高效算法,即点、半定型放松和顺序排位限制技术,以解决由此产生的问题。模拟结果证实了拟议算法的有效性,并展示了用户集组装对网络吞吐功能的影响。