Improved MIMO precoding for decentralized receivers resembling concepts from lattice reduction

This paper presents an improved version of precoding, i.e., nonlinear preequalization, for situations with one central transmitter (e.g., base station) and a number of distributed receivers (e.g., mobile terminals). The new method is based on Tomlinson-Harashima precoding, applied to multipleinput/multiple-output (MIMO) channels, and inspired by the concept of lattice-reduction-aided detection in MIMO communication systems. We show that using the proposed technique, a considerable degree of diversity can be gained over linear preequalization, as well as conventional precoding.