论文标题
通过原子规范最小化，RIS AID的MMWAVE MIMO系统的通道估计
Channel Estimation for RIS-Aided mmWave MIMO Systems via Atomic Norm Minimization
论文作者
论文摘要
可重新配置的智能表面（RIS）可以通过将电磁波撞击到任何所需的方向，从而破坏Snell将军的反射定律，从而塑造无线电传播环境。但是，RI的最佳控制需要通过RIS将基站（BS）和移动站（MS）链接到彼此的单个通道的完美通道状态信息（CSI）。因此，需要在BS或MS上有效地进行超分辨率通道（参数）估计，并使用CSI反馈对RIS控制器进行反馈。在本文中，我们对无直接BS-MS通道的RIS辅助毫米波（MMWAVE）MIMO系统采用了两阶段的通道估计方案，使用原子规范最小化来顺序估计通道参数，即，即角参数，角度参数，角度差异，和传播路径的产物。我们评估了参数估计值，RIS增益，平均有效频谱效率结合的均方误差，以及设计的波束成形和组合向量与最佳量之间的平均平方距离。结果表明，与现有基准方案相比，所提出的方案实现了超分辨率估计，从而在随后的数据传输阶段提供了有希望的性能。
A reconfigurable intelligent surface (RIS) can shape the radio propagation environment by virtue of changing the impinging electromagnetic waves towards any desired directions, thus, breaking the general Snell's reflection law. However, the optimal control of the RIS requires perfect channel state information (CSI) of the individual channels that link the base station (BS) and the mobile station (MS) to each other via the RIS. Thereby super-resolution channel (parameter) estimation needs to be efficiently conducted at the BS or MS with CSI feedback to the RIS controller. In this paper, we adopt a two-stage channel estimation scheme for RIS-aided millimeter wave (mmWave) MIMO systems without a direct BS-MS channel, using atomic norm minimization to sequentially estimate the channel parameters, i.e., angular parameters, angle differences, and products of propagation path gains. We evaluate the mean square error of the parameter estimates, the RIS gains, the average effective spectrum efficiency bound, and average squared distance between the designed beamforming and combining vectors and the optimal ones. The results demonstrate that the proposed scheme achieves super-resolution estimation compared to the existing benchmark schemes, thus offering promising performance in the subsequent data transmission phase.
