The performance of Simultaneous Wireless Information and Power Transfer (SWIPT) is mainly constrained by the received Radio-Frequency (RF) signal strength. To tackle this problem, we introduce an Intelligent Reflecting Surface (IRS) to compensate the propagation loss and boost the transmission efficiency. This paper proposes a novel IRS-aided SWIPT system where a multi-carrier multi-antenna Access Point (AP) transmits information and power simultaneously, with the assist of an IRS, to a single-antenna User Equipment (UE) employing practical receiving schemes. Considering harvester nonlinearity, we characterize the achievable Rate-Energy (R-E) region through a joint optimization of waveform, active and passive beamforming based on the Channel State Information at the Transmitter (CSIT). This problem is solved by the Block Coordinate Descent (BCD) method, where we obtain the active precoder in closed form, the passive beamforming by the Successive Convex Approximation (SCA) approach, and the waveform amplitude by the Geometric Programming (GP) technique. To facilitate practical implementation, we also propose a low-complexity design based on closed-form adaptive waveform schemes. Simulation results demonstrate the proposed algorithms bring considerable R-E gains with robustness to CSIT inaccuracy and finite IRS states, and emphasize the importance of modeling harvester nonlinearity in the IRS-aided SWIPT design.
翻译:模拟无线信息和电源传输(SWIPT)的性能主要受到接收的无线电-频频信号强度的限制。 为了解决这一问题,我们引入了一个智能反射表面(IRS),以弥补传播损失,提高传输效率。本文件建议建立一个新型的IRS辅助SWIPT系统,在这个系统中,多载多载多保险多端接入接入点(AP)在IRS的协助下,使用实用的接收计划,将信息和权力同时传送到单一保险用户设备(UE)。考虑到收割器不线性,我们通过在传输器频道国家信息的基础上联合优化波形、主动和被动反射波成型(IRS)区域,将信息和电源同步多载多载多载多载断层接入接入接入接入点(SWIPT)系统(AP)同时传输信息与电源连接,通过Cevex Approxximcolation (USASC) 方法的被动化模型,以及可实现的电压缩缩缩图(GGPT)区域,我们还提议在基于低度的S-RIMFS-S-S-SLSBSBSLSBSASSSBSS 的系统格式设计中, 的快速度设计中,将快速度度的大幅演算算算算法的大幅推进结果。