Abstract: A monopulse antenna feed system utilizing multiple modes within the feed. A TEM mode and two TE.degree..sub.11 modes that are orthogonal and in phase quadrature are utilized in the antenna feed system to provide tracking information and data communication from a far-field source of circularly polarized radiation. The output from a port that is responsive to the TEM mode is compared with the output from a port that is responsive to the TE.degree..sub.11 modes to obtain tracking information and the output from the latter port also provides a channel for communication of data. The phase of the TEM mode relative to the phase of the TE.degree..sub.11 modes is indicative of the angular rotational position of a far-field source relative to the axis of the feed system and the relative amplitude of the TEM mode is indicative of the angular displacement of the far-field source away from the axis of the feed system.

Abstract: A portable reflector antenna assembly which is readily assemblable and disassemblable for use in the field has a triangular base frame employing three beam members which are joined together at their ends with hinge type knuckles which are slidably positioned on three legs. The legs have integral cup shaped pads near the bottom ends thereof and are driven into the ground until the cups abut against the ground to provide lateral and vertical support in the soil. The frame can be adjusted on the legs for both height and leveling by virtue of the slidable movement of each of the knuckles along the legs, and when in the desired position are clamped to the legs by means of lever-cam actuated draw bolts. The reflector member of the antenna is supported along its rim by means of pivotal supports and clamps, the bottom edge of the antenna being slidably adjustable in azimuth along the curved front beam member of the frame and clamped to the front beam member by means of clamping members.

Abstract: A monopulse antenna feed system utilizing multiple modes within the feed. In one embodiment a TEM mode and one or two TE.phi..sub.11 modes are utilized in the antenna feed system to provide a data and a reference signal responsive to the one or two TE .sub.11 modes and to provide an error indicating signal responsive to the TEM mode that provides monopulse tracking operation. The relative phase of the TEM mode and the one or two TE .sub.11 modes is indicative of the off-axis orientation of a far-field source relative to the axis of the antenna system. The relative amplitude of the TEM mode is indicative of the angular departure the source from the axis.