论文标题
具有非理想硬件的大反射表面的频道估计和功率缩放定律
Channel Estimation and Power Scaling Law of Large Reflecting Surface with Non-Ideal Hardware
论文作者
论文摘要
大型反射表面（LRS）已成为提高无线通信系统能量和光谱效率的新解决方案。大多数现有的研究是在理想硬件的假设中进行的，硬件障碍的影响很少受到关注。但是，当我们评估系统性能时，应考虑不可忽略的硬件障碍。在本文中，我们考虑使用硬件障碍的LRS辅助通信系统，并专注于渠道估计研究和功率扩展法分析。首先，通过线性最小均方根误差估计，我们从理论上表征了通道估计性能和损伤水平，反射元素的数量和飞行功率之间的关系。之后，我们分析了功率扩展定律，并揭示了基站（BS）具有完美的渠道状态信息，则可以使用户的传输能力与BS天线的数量和反射元素数量的平方成反比，而无需降低性能；如果BS的估计通道状态信息不完美，为了实现相同的性能，则可以将用户的传输功率呈现与BS天线数量和反射元素数量的平方的平方根成反比。
Large reflecting surface (LRS) has emerged as a new solution to improve the energy and spectrum efficiency of wireless communication system. Most existing studies were conducted with an assumption of ideal hardware, and the impact of hardware impairments receives little attention. However, the non-negligible hardware impairments should be taken into consideration when we evaluate the system performance. In this paper, we consider an LRS assisted communication system with hardware impairments, and focus on the channel estimation study and the power scaling law analysis. First, with linear minimum mean square error estimation, we theoretically characterize the relationship between channel estimation performance and impairment level, number of reflecting elements, and pilot power. After that, we analyze the power scaling law and reveal that if the base station (BS) has perfect channel state information, the transmit power of user can be made inversely proportional to the number of BS antennas and the square of the number of reflecting elements with no reduction in performance; If the BS has imperfectly estimated channel state information, to achieve the same performance, the transmit power of user can be made inversely proportional to the square-root of the number of BS antennas and the square of the number of reflecting elements.
