TRACKING SYSTEM, TRACKING METHOD, AND PROGRAM

摘要

A rotation determiner (23) determines whether the azimuth (AZ) angle of an antenna (3) rotates beyond a rotation range within a predetermined duration of time on the basis of a predicted orbit value. When the AZ angle of the antenna (3) is determined to rotate beyond the rotation range, an orbit determiner (24) determines whether an estimated satellite position is within a drivable range in which the AZ angle rotates from a reference value beyond the rotation range, and in which an xEL axis can be driven in a state in which the AZ angle is set to a predetermined value that is permissible for the AZ angle. When the AZ angle rotates beyond the rotation range and while the estimated satellite position is within the drivable range, a determiner (22) sends a command to a switching section (17) to cause three-axis control, and a command to cause an AZ command operator (15) to output a command value that keeps the AZ angle at a predetermined value. When the AZ angle rotates beyond the rotation range and while the estimated satellite position is not within the drivable range, or when the AZ angle does not rotate beyond the rotation range, the determiner (22) sends a command to the switching section (17) to cause two-axis control.