Antenna Digital Control for the Directed Mirror Antenna Radar (DMAR)

摘要

The reflector dish of the Radar System antenna is a flat mirrored disc, six feet in diameter, supported by a gimballed structure providing rotational motion in 2 axes. The gimballed structure is such that the 2 axes of rotation intersect at a point which is diametrically centered on the dish but is located just behind it. Encoders and tachometers located on each of the gimbals measure angle and angular rate. Motion of the mirror is provided by 4 hydraulically driven pistons whose construction is such as to provide maximum linearization of the actuation with respect to motion of the dish. Wide dynamic response is a requirement for the system. The radar feed system, which provides appropriate beam shaping in directing the beam towards the mirror, remains stationary eliminating the need for rotating joints. Control of the radar's beams direction is provided for by motion of the mirrored surface. The All Digital Controller is a fast, programmable digital machine dedicated to servo control of multi axis or highly complex systems. Its heart is a digital processor designed specifically for closed loop control.