Reduction of lower sidelobe levels in a large deployable mesh reflector antenna as a means of decreasing the effective mass of communication equipment

Abstract

Reducing sidelobe levels and lowering the effective mass of the equipment are important measures in the design of large deployable mesh reflector multibeam antennas used for mobile communication satellites with frequency reuse. In this paper, a method of converting from sidelobe levels to effective mass is described. Then the effects produced by the sidelobe level on the mass of the mesh reflector and the communication equipment are analyzed in the case of a cluster-fed offset parabolic mesh reflector antenna. The surface density of the mesh reflector decreases with an increase in the aperture diameter, and the output efficiency of the solid-state power amplifier decreases with an increase in output power. Next, assuming one transponder for each beam and using the EIRP of all the beams as a parameter, the relations between the sidelobe level, the minimum communication equipment mass, and the antenna aperture are described. The relation between the gain and the number of beams when the communication equipment mass is minimum is derived and the ratio of mesh reflector mass to the total mass of communication equipment is determined.