Near Optimum User Selection for Minimum Mean Square Error Based Tomlinson Harashima Precoding

This paper proposes novel user selection techniques for the Tomlinson-Harashima precoding (THP) based on the minimum mean square error (MMSE) criterion. These techniques utilize a part of the intermediate values in the derivation of the THP weight, which makes it possible to implement the techniques with lower computational complexity. For further complexity reduction, we propose successive user selection techniques based on the techniques proposed above where user terminals are selected one by one. It is confirmed by computer simulations that the proposed techniques outperform conventional selection techniques. The computational complexity of the successive selection techniques is about 1/20 as small as that of the original selection techniques when 4 user terminals are selected out of 10 terminals.