Patent ID: 8174456

Claim:
An antenna apparatus that executes a pointing control so as to point a directional antenna installed on a mobile body toward a satellite using a two-axis mechanism, the antenna pointing control apparatus comprising: a support member supporting the directional antenna rotatably about an elevation axis; a base pedestal supporting the directional antenna and the support member, the base pedestal being rotatable about an azimuth axis; elevation axis rotating means for rotationally driving the directional antenna about the elevation axis; azimuth axis rotating means for rotationally driving the directional antenna, the support member, and the base pedestal about the azimuth axis; recording means for recognizing and recording movement and rocking of the mobile body once per prescribed cycle period; measuring means for measuring a satellite bearing; error detecting means for detecting a pointing error of the directional antenna based on a measurement result from the measuring means; and determining means for determining whether or not the satellite will pass within a prescribed region about an extension line of the azimuth axis of the mobile body based on the measurement result from the measuring means and a record from the recording means, the determining means issuing an instruction to control the elevation axis and the azimuth axis using a two-axis control in accordance with the pointing error from the error detecting means if the determining means determines that the satellite will not pass within the prescribed region about the extension line of the azimuth axis of the mobile body, and the determining means issuing an instruction to operate the azimuth axis rotating means and the elevation axis rotation means based on a virtual three-axis control that assumes a virtual cross elevation axis exists and controls the elevation axis and the azimuth axis in accordance with the pointing error from the error detecting means if the determining means determines that the satellite will pass within the prescribed region about the extension line of the azimuth axis of the mobile body.