A dual reflector antenna with adjustable subreflector for hybrid mechanical-electronic scanning

This paper presents some results of the ESA project ¿Hybrid Mechanical-Electronic Pointing System¿, which considers future scenarios using the Q/V band on satellite communications. The main characteristic of the antenna is to provide two separate controls of the main beam: electronic control and mechanical control. The mechanical control is produced by an adjustable subreflector, working cooperatively with the electronic beam control provided by a source array as primary feed of the antenna system. A Gregorian Confocal configuration has been adopted. The subreflector design has been developed under Geometrical Optics approximation and Simulated Annealing optimization techniques to provide best-fit-paraboloidal representations of the surface that can be implemented with a limited number of mechanical actuators.