Cascaded Channel Estimation for Large Intelligent Metasurface Assisted Massive MIMO

Understand

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.