论文标题
可重新配置的智能表面辅助通信系统的Cramér-rao下限的渐近可实现性
Asymptotic Achievability of the Cramér-Rao Lower Bound of Channel Estimation for Reconfigurable Intelligent Surface Aided Communication Systems
论文作者
论文摘要
为了在可重新配置的智能表面辅助毫米波系统中实现关节主动和被动的光束成形增长，需要准确估算反射的级联信道。文献中已经提出了许多解决这个问题的策略。但是，可以实现此类估计的Cramér-Rao下限（CRLB）仍然不确定。为了填补这一空白，我们首先利用离散傅立叶变换矩阵和kronecker产品的属性，将通道估计问题转换为稀疏信号恢复问题。然后，利用基于典型性的联合估计器来执行信号恢复任务。我们表明，通过数学证明和数值模拟，本字母中提出的解决方案实际上可以渐近地实现CRLB。
To achieve the joint active and passive beamforming gains in the reconfigurable intelligent surface assisted millimeter wave system, the reflected cascade channel needs to be accurately estimated. Many strategies have been proposed in the literature to solve this issue. However, whether the Cramér-Rao lower bound (CRLB) of such estimation is achievable still remains uncertain. To fill this gap, we first convert the channel estimation problem into a sparse signal recovery problem by utilizing the properties of discrete Fourier transform matrix and Kronecker product. Then, a joint typicality based estimator is utilized to carry out the signal recovery task. We show that, through both mathematical proofs and numerical simulations, the solution proposed in this letter can in fact asymptotically achieve the CRLB.
