The Highly Shaped Beam Telemetry Antenna for the Spot Satellite Payload

The telemetry antenna developed for the SPOT satellite payload, and functioning in the frequency band 8.2 - 8.31 GHz, is a highly shaped beam antenna, principally constituted by a symmetric reflector of shaped profile, and illuminated by an adequate primary feed. Two solutions of primary feed are investigated, the first one with four support struts, and the second one with an axial monopod feed. Computed and measured radiation patterns are shown for the antenna in free space and in the presence of the satellite platform. Mechanical and technological antenna design is also examined.