J4 ›› 2015, Vol. 42 ›› Issue (2): 1-6+101.doi: 10.3969/j.issn.1001-2400.2015.02.001

• Original Articles •     Next Articles

Number of users optimization for large-scale MIMO systems

LI Xiaohui;WU Yaying;HEI Yongqiang   

  1. (State Key Lab. of Integrated Service Networks, Xidian Univ., Xi'an  710071, China)
  • Received:2013-11-11 Online:2015-04-20 Published:2015-04-14
  • Contact: LI Xiaohui E-mail:xhli@mail.xidian.edu.cn

Abstract:

The large-scale MIMO system using the regularized zero-forcing (RZF) precoding is considered and the space degree of freedom (DOF) is introduced. The expression for the approximate ergodic capacity is derived and the problem of the joint RZF precoding and user number optimization is presented. Theoretical analysis illustrates that the joint optimization problem can be transformed to the user number optimization problem under some conditions. It can be derived that the unique optimum solution can be obtained by using a bisection based joint optimal algorithm. Simulation results show that the proposed algorithm can achieve almost the same capacity as the best optimization algorithm but with a much lower complexity in the large-scale MIMO systems.

Key words: large-scale MIMO, space degree of freedom, approximate capacity, regularized zero-forcing, user number

CLC Number: 

  • TN 929.5