论文标题
与RIS辅助无线系统的通道分布的准确闭合形式近似
Accurate Closed-Form Approximations to Channel Distributions of RIS-Aided Wireless Systems
论文作者
论文摘要
本文提出了高度准确的闭合形式近似值，以引导两种基于两种不同的可重构智能表面（RIS）的无线系统设置的分布，即双跳RIS-RIS-ADED（RIS-DH）方案和RIS AIDED TRANSMIT（RIS-T）方案。与以前的工作不同，提议的近似值表明，对于反映metasurface元素的任意数字$ n $非常紧。然后，我们的发现将其应用于所考虑系统的性能分析，其中停电概率，位错误率和平均通道容量被得出。结果表明，RIS-DH和RIS-T方案的可实现多样性订单分别为$ n-1 <g_d <n $和$ n $。此外，据揭示，这两个方案都无法提供多重增益，只能实现多样性的增长。对于RIS-DH方案，通道与仅具有一个自由度的钥匙孔多输入多输出（MIMO）通道相似，而RIS-T方案类似于发送多样性结构。
This paper proposes highly accurate closed-form approximations to channel distributions of two different reconfigurable intelligent surface (RIS)-based wireless system setups, namely, dual-hop RIS-aided (RIS-DH) scheme and RIS-aided transmit (RIS-T) scheme. Differently from previous works, the proposed approximations reveal to be very tight for arbitrary number $N$ of reflecting metasurface's elements. Our findings are then applied to the performance analysis of the considered systems, in which the outage probability, bit error rate, and average channel capacity are derived. Results show that the achievable diversity orders $G_d$ for RIS-DH and RIS-T schemes are $N-1<G_d<N$ and $N$, respectively. Furthermore, it is revealed that both schemes can not provide the multiplexing gain and only diversity gains are achieved. For the RIS-DH scheme, the channels are similar to the keyhole multiple-input multiple-output (MIMO) channels with only one degree of freedom, while the RIS-T scheme is like the transmit diversity structure.
