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arXiv · 1905.07948

Cascaded Channel Estimation for Large Intelligent Metasurface Assisted Massive MIMO

Zhen-Qing He·Xiaojun Yuan
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Abstract

In this letter, we consider the problem of channel estimation for large intelligent metasurface (LIM) assisted massive multiple-input multiple-output (MIMO) systems. The main challenge of this problem is that the LIM integrated with a large number of low-cost metamaterial antennas can only passively reflect the incident signal by a certain phase shift, and does not have any signal processing capability. To deal with this, we introduce a general framework for the estimation of the transmitter-LIM and LIM-receiver cascaded channel, and propose a two-stage algorithm that includes a sparse matrix factorization stage and a matrix completion stage. Simulation results illustrate that the proposed method can achieve accurate channel estimation for LIM-assisted massive MIMO systems.

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Zhen-Qing He, Xiaojun Yuan. 2019-05-20. Cascaded Channel Estimation for Large Intelligent Metasurface Assisted Massive MIMO. https://arxiv.org/abs/1905.07948

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