Zero-forcing Precoder: A Special Constructive Interference Precoder for PSK Signals

Recently, constructive interference precoders have been considered for downlink communication systems to utilize the multiuser interference constructively. Such precoders are normally obtained by solving constrained optimization problems at each symbol period. We demonstrate that there exists an analytic solution to a constructive interference precoder under the constraint of QoS for phase-shift keying (PSK) symbols. In this case, the computational cost is saved for the precoder design without solving the optimization problem.