  This paper evaluates the performance of multi-user massive multiple-input
multiple-output (MIMO) systems in which the base station is equipped with a
dynamic metasurface antenna (DMA). Due to the physical implementation of DMAs,
conventional models widely-used in MIMO are no longer valid, and
electromagnetic phenomena such as mutual coupling, insertion losses and
reflections inside the waveguides need to be considered. Hence, starting from a
recently proposed electromagnetic model for DMAs, we formulate a zero-forcing
optimization problem, yielding an unconstrained objective function with known
gradient. The performance is compared with that of full-digital and hybrid
massive MIMO, focusing on the impact of insertion losses and mutual coupling.
