MMSE Symbol Level Precoding Under a Per Antenna Power Constraint for Multiuser MIMO Systems With PSK Modulation

This letter proposes two MMSE symbol-level precoding approaches considering a strict per antenna power constraint and PSK modulation for perfect and imperfect channel state information scenarios. The proposed designs are formulated as second-order cone programs, allowing for an optimal solution via the interior point method. Numerical results confirm that, for the scenario with perfect channel state information, the proposed designs outperform the existing techniques in terms of bit-error-rate for low and intermediate signal-to-noise-ratio. Numerical evaluations also confirm the superiority of the proposed robust MMSE design in the presence of channel state information imperfection.