Spectral efficiency improvement by base station antenna pattern control for land mobile cellular systems

The paper proposes use of an adaptive array base station in order to increase spectral efficiency without decreasing cell radius. The base station antenna controls its directivity pattern to reduce co-channel interference by applying an adaptive array technique. Computer simulation results show that the cluster size can be reduced to one, indicating that one can reuse the same frequency group at all cells. Thus, the improvement in spectral efficiency is as much as 16 times as that of an omni-antenna. Moreover, load sharing, which is expected to improve channel utilization for unbalanced load situations, is available by cell overlapping