Elevation Plane Spatial Multicell Interference Mitigation with No CSI Sharing

Abstract

We study downlink transmission in a cellular network with multi-antenna base stations (BSs) and single-antenna users. We propose a novel coordinated transmission strategy that controls the intercell interference (ICI) via exploiting the elevation plane of the wireless channel. The key idea is to divide the area of each cell into two disjoint vertical regions and to serve the non-adjacent vertical regions in the neighboring cells according to a set of pre-determined coordinated transmission patterns. A scheduler is used to dynamically allocate the available time-slots among transmission patterns. By appropriately adapting the elevation angle of the antenna main beam, denoted as tilt, at the BSs in each pattern, ICI can be effectively suppressed. Unlike the state-of-the-art coordinated transmission schemes, the proposed technique requires no channel state information sharing among BSs and/or infeasible BS tilting capabilities, but achieves comparable performance.