Improved MIMO precoding for decentralized receivers resembling concepts from lattice reduction

The paper presents an improved version of precoding, i.e., nonlinear pre-equalization, 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 multiple-input-multiple-output (MIMO) channels, and inspired by the concept of lattice-reduction-aided detection in MIMO communication systems. We show that, by using the proposed technique, a considerable degree of diversity can be gained over linear pre-equalization, as well as conventional precoding.