Throughput improvement by combined tilting of base station antenna

Most cellular mobile communications systems use sectored cell configurations such as three or six sectors. In these systems, reducing the back-lobe interference of the BS sector antenna that arrives at the other sectors in the same cell is very important in order to improve the SINR (Signal to Interference and Noise power Ratio) and thus cell throughput. Setting the beam tilt angle of the back-lobe deeper than that of main-lobe for the BS sector antenna greatly reduces the back-lobe interference. This function can be realized by using a combination of electrical and mechanical beam tilting. This function has been used for area shaping in rural cells, but not so far for SINR improvement in urban cells. In order to apply this function to the urban cellular BS sector antenna effectively, careful optimization is required. We clarify the improvements in SINR and cell throughput possible when applying the combined tilting technique to cellular systems.