Boosting performance of multi-user Tomlinson-Harashima precoding

Abstract

In the precoding matrices of the best-known multi-user Tomlinson-Harashima precoder, only the sum of noise powers of all users is used; information on the individual users' powers is thus under-utilised. A method is proposed to take into account the individual noise powers of users in the precoding matrices for system-wise performance optimisation, while users' noise powers may not be explicitly fedback to save uplink bandwidth.