Beyond diagonal reconfigurable intelligent surface (BD-RIS) is a novel branch of RIS which breaks through the limitation of traditional RIS with diagonal scattering matrices. However, the existing research focuses on BD-RIS with fixed architectures regardless of channel state information (CSI), which limit the achievable performance of BD-RIS. To solve this issue, in this paper, we propose a novel dynamically group-connected BD-RIS based on a dynamic grouping strategy. Specifically, RIS antennas are dynamically divided into several subsets adapting to the CSI, yielding a permuted block-diagonal scattering matrix. To verify the effectiveness of the proposed dynamically group-connected BD-RIS, we propose an efficient algorithm to optimize the BD-RIS with dynamic grouping for a BD-RIS-assisted multi-user multiple-input single-output system. Simulation results show that the proposed dynamically group-connected architecture outperforms fixed group-connected architectures.
翻译:超越对二相可调整的智能表面(BD-RIS)是RIS的一个新分支,它打破了传统的对二相分布矩阵的RIS限制。然而,现有的研究侧重于对固定结构的BD-RIS,而不论频道状态信息(CSI)如何,这限制了BD-RIS的可实现性能。为了解决这个问题,我们在本文件中提出一个基于动态组合战略的新颖的动态分组连接的BD-RIS。具体地说,RIS天线被动态地分为几个子组,可适应 CSI,产生一个固定的区块-对角分布矩阵。为核实拟议的动态分组连接BD-RIS的有效性,我们建议一种高效的算法,以动态组合优化BD-RIS辅助的多用户多输入单元输出系统。模拟结果显示,拟议的动态组合连接结构超越了固定的组合连接结构。