Efficient vector perturbation in multi-antenna multi-user systems based on approximate integer relations

Authors: Dominik Seethaler and Gerald Matz

Affiliation: Vienna University of Technology

e-mail: dominik.seethaler@tuwien.ac.at ,  gmatz@nt.tuwien.ac.at

Abstract

Precoding and pre-equalization are very promising technique for scenarios, where a transmitter uses multiple antennas to serve multiple non-cooperative users. Using a sphere precoder in such a setting has the potential to outperform other techniques like Tomlinson-Harashima-type precoding. However, the computational complexity of sphere-precoding is very high on average and even prohibitive for poorly conditioned channel realizations. In this paper, we use a geometric approach to develop a novel precoding technique that achieves a performance close to the sphere precoder while maintaining a significantly lower complexity.