A Compact Multi-faceted Reflectarray based-on Cassegrain Optics

Abstract

This paper presents a compact Cassegrain reflector antenna in which a multi-faceted reflectarray plays the role of main reflector. The reflectarray surface is composed by three identical panels, arranged following a cylindricalparabolic structure. The designed antenna provides a dual linear polarization (LP) and radiates a pencil around a center frequency of 31 GHz. The performance of this antenna is evaluated and compared with an equivalent single-facet Cassegrain reflectarray. The sectorization in the multi-faceted structure relaxes the phase requirements to be provided by the unit-cell, which reduces the phase errors in simple cell topologies. The multi-faceted structure achieves a better performance in terms of gain bandwidth, showing an improvement of at least 30% in the relative bandwidth and 50% in the gain-bandwidth product regarding a conventional single-facet reflectarray.