Patent ID: 8649457
Filing Date: 2014-02-11
Classification: H04B,H04L

Abstract:
1. Precoding process for a transmitter of a MU-MIMO communication system comprising: M antennas in the transmitter and K User Equipments (UE), said precoding being based on a Regularized Zero Forcing (R-ZF) linear precoding of the type: With: H being a complex matrix representative of the K×M channel estimates, said H matrix comprising channel coefficients which are correlated with corresponding correlation coefficients being the entries of a correlation matrix ⊖ T , I K and I M being the identity matrix, respectively of size K×K and M×M; And α being the regularization parameter, wherein α is computed as follows: a) computing the correlation matrix ⊖ T ; b) initializing two parameters α max and α min ; c) computing α=½(α max +α min ); d) determining ( 140 ) for z=−α the value of S (S H′ Θ H′ (z)) solving the fixed-point equation: With λ being the eigenvalues of the correlation matrix ⊖ T , μ being the empirical eigenvalue distribution functions of ⊖ T and β being M/K; e) determining for z=−α the value of S d solving the fixed-point equation: f) computing the equation g) adapting the interval [α min , α max ] as follows: if F−P<0, with P being the total available transmit power, then computing ( 180 ) α max =α, otherwise computing α min =α.