Vertical sectorization techniques for active antenna systems

In this paper, we study vertical sectorization techniques for multiple-input single-output (MISO) downlink active antenna systems (AAS). In the AAS, antenna beam patterns can be adjusted in each sector and multiple vertical beams can form the vertical sectorization. Since an exhaustive search based vertical sectorization algorithm requires high computational complexity to find the optimal tilt angles, we propose a low complexity vertical sectorization algorithm which is close to the performance of the exhaustive algorithm with much reduced complexity.