论文标题
IRS辅助通信中的功率效率，间接费用和复杂性权衡 - 二次移动设计
Power Efficiency, Overhead, and Complexity Tradeoff in IRS-Assisted Communications -- Quadratic Phase-Shift Design
论文作者
论文摘要
在本文中，我们专注于大型智能反射表面（IRSS），并提出了一种新的代码簿构造方法，以获得IRS单位单元格的一组预先设计的相移配置。由于用于频道估计的开销和对IRS辅助通信量表的在线优化量表的复杂性具有相移代码簿的大小，因此小型代码书的设计非常重要。我们表明，功率效率与代码书的规模之间存在基本的权衡。我们首先分析了基线设计的这一权衡，这些设计在IRS中采用线性相变。随后，我们表明，针对小型代码手册的有效设计要求在IRS上进行高阶换档变化。因此，我们提出了二次移位设计，从代码书大小的函数中得出其系数，并分析其性能。我们的仿真结果表明，所提出的设计比线性基线设计具有更高的小型代码手册功率效率。
In this paper, we focus on large intelligent reflecting surfaces (IRSs) and propose a new codebook construction method to obtain a set of predesigned phase-shift configurations for the IRS unit cells. Since the overhead for channel estimation and the complexity of online optimization for IRS-assisted communications scale with the size of the phase-shift codebook, the design of small codebooks is of high importance. We show that there exists a fundamental tradeoff between power efficiency and the size of the codebook. We first analyze this tradeoff for baseline designs that employ a linear phase-shift across the IRS. Subsequently, we show that an efficient design for small codebooks mandates higher-order phase-shift variations across the IRS. Consequently, we propose a quadratic phase-shift design, derive its coefficients as a function of the codebook size, and analyze its performance. Our simulation results show that the proposed design yields a higher power efficiency for small codebooks than the linear baseline designs.
