Patent ID: 8792942

Claim:
A base station device, comprising: a first antenna which transmits a radio signal in a downlink; a second antenna which receives a radio signal in an uplink; and a tilt angle control unit which controls a tilt angle of the first antenna and the second antenna to decrease a difference in a position of a cell boundary of the downlink and a position of the cell boundary of the uplink based on a first downlink communication quality and a first uplink communication quality with respect to a first base station device and on a second downlink communication quality and a second uplink communication quality with respect to an adjacent second base station device, wherein the tilt angle control unit groups mobile stations receiving communications from the first base station device and the adjacent second base station device into a first group, in which a highest communication quality of the downlink is measured based on reception power, and a second group, in which the highest communication quality of the uplink is measured based on reception power, compares a number of mobile stations in the first group and a number of mobile station in the second group, and controls the tilt angle of the first antenna or the second antenna to decrease a mismatch between the number of mobile stations in the first group and the number of mobile stations in the second group, wherein the tilt angle control unit further determines whether a cell boundary of the downlink or a cell boundary of the uplink is closer to the first base station device based on the comparison of the number of mobile stations between the first group and the number of mobile stations in the second group.