Improved iterative Water-Filling algorithm in MUMIMO system

In this paper, an efficient user selection method for traditional iterative Water-Filling algorithm in Gaussian multiuser broadcast channel is developed to reduce the computational complexity. The new algorithm selects some effective users from all the users, and then allocates the entire power among the selected users applying Water-Filling algorithm. The vector Gaussian broadcast channel and the matrix Gaussian broadcast channel are considered respectively and the corresponding user selection methods are proposed. Theoretical analysis and simulation results show that the new algorithm can significantly improve the computational efficiency of the traditional iterative Water-Filling power allocation and can obtain almost the optimal sum capacity.