J4 ›› 2009, Vol. 36 ›› Issue (4): 596-601.

• Original Articles • Previous Articles     Next Articles

Low complexity ordering algorithm for multiuser  MIMO Tomlinson-Harashima precoding

WANG Wei;HU Mei-xia;ZHANG Hai-lin   

  1. (State Key Lab. of Integrated Service Networks, Xidian Univ., Xi'an  710071, China)
  • Received:2008-10-31 Online:2009-08-20 Published:2009-09-28
  • Contact: WANG Wei E-mail:weiwang@mail.xidian.edu.cn

Abstract:

The nonlinear Tomlinson-Harashima precoding(THP) algorithm is an effective solution for MIMO broadcast. However, the performance of the THP strongly depends on the ordering of precoding symbols. To compare different ordering THP algorithms effectively, an ordering gain factor is defined in this paper. And we propose a low complexity ordering THP algorithm based on the approximate equal-diagonal QR decomposition. The proposed algorithm obtains a triangle matrix with approximate equal diagonal elements by rearranging the order of the channel matrix's rows to maximize the ordering gain. Simulation results reveal that the proposed algorithm has a significant reduction of computational complexity at the expense of only slight performance degradation compared to the optimal ordering THP algorithm.

Key words: multiuser, multiple input multiple output, downlink, Tomlinson-Harashima precoding

CLC Number: 

  • TN929.5