Block diagonalization for multi-user MIMO with other-cell interference

Abstract--Block diagonalization is one approach for linear precoding in the multiple-input multiple-output broadcast channel that sends multiple interference free data streams to different users in the same cell. Unfortunately, block diagonalization neglects other-cell interference (OCI), which limits the performance of users at the edge of the cell. This paper presents an OCI-aware enhancement to block diagonalization that uses a whitening filter for interference suppression at the receiver and a novel precoder using the interference-plus-noise covariance matrix for each user at the transmitter. For complex Gaussian matrix channels, the asymptotic sum rate of the proposed system is analyzed under a large antenna assumption for isotropic inputs and compared to conventional block diagonalization. The capacity loss due to OCI is quantified in terms of results from single-user MIMO capacity. Several numerical examples compare achievable sum rates, the proposed asymptotic rates, and the ca...

• Type: Journal
• Year: 2008
• Where: TWC
• Authors: Seijoon Shim, Jin Sam Kwak, Robert W. Heath Jr., Jeffrey G. Andrews
• Keywords: Block Diagonalization, Conventional Block Diagonalization, Sum Rates, TWC 2008