Inter-Cell Scheduling in a Cellular MIMO System

The capacity and robustness of cellular MIMO systems is very sensitive to other-cell interference, which will in practice necessitate network level interference reduction strategies [1]– [3]. As an alternative to traditional static frequency reuse patterns, we investigate inter-cell scheduling among neighboring base stations, where adjacent base stations and an (arbitrarily chosen) home base station cooperatively schedule their transmissions to reduce other-cell interference. Just as frequency reuse achieves OCI reduction at the expense of decreasing spectral efficiency by the frequency reuse factor, cooperatively scheduled transmission reduces OCI at the expense of decreasing throughput by the transmit duty cycle. There are two important advantages of inter-cell scheduling relative to traditional frequency reuse. First, universal frequency reuse can still be adopted, achieving an interference averaging effect, simplifying frequency planning in deployment, and reducing the number of required frequency channels for the system. Second, inter-cell scheduling achieves an additional gain termed expanded multiuser diversity if straightforward opportunistic scheduling is employed among neighboring base stations.