TILT ANGLE OPTIMIZATION APPARATUS, TILT ANGLE OPTIMIZATION METHOD, AND PROGRAM

1 . A tilt angle optimization apparatus configured to perform optimization of a tilt angle of each of antennas at each of base stations forming a cellular network, the tilt angle optimization apparatus comprising:

a processor; and

a memory storing program instructions that cause the processor to:

construct a performance model by modeling a relationship between a number of active users of each of the antennas and performance providable by each of the antennas;

estimate a user distribution of active users around each of the base stations based on statistical data observed at each of the base stations; and

obtain the tilt angle of each of the antennas based on the constructed performance model and the estimated user distribution in order to maximize area quality in a specified target area.

2 . The tilt angle optimization apparatus according to claim 1 , wherein the program instructions cause the processor to construct the performance model by using a plurality of pieces of data including sets of the number of active users and the performance actually observed at each of the antennas, classifying the number of active users into arbitrary bins, and using a maximum value within each of the bins as a representative point.

3 . The tilt angle optimization apparatus according to claim 1 , wherein the program instructions cause the processor to construct the performance model by applying Gaussian process regression.

4 . The tilt angle optimization apparatus according to claim 1 , wherein the program instructions cause the processor to output the tilt angle of each of the antennas in order to maximize the area quality in the target area under a restriction condition.

5 . The tilt angle optimization apparatus according to claim 4 , wherein the restriction condition is a restriction regarding coverage of the target area or a restriction regarding minimum area quality.

6 . A tilt angle optimization method executed by a tilt angle optimization apparatus configured to perform optimization of a tilt angle of each of antennas at each of base stations forming a cellular network, the tilt angle optimization method comprising:

constructing a performance model by modeling a relationship between a number of active users in each of the antennas and performance providable by each of the antennas;

estimating a user distribution of active users around each of the base stations based on statistical data observed at each of the base stations; and

obtaining the tilt angle of each of the antennas based on the constructed performance model and the estimated user distribution in order to maximize area quality in a specified target area.

7 . A non-transitory computer-readable recording medium storing a program for causing a computer to execute the method of claim 6 .