Wideband multibeam arrays of long slots fed by quasi-optical systems

This paper summarizes the latest advances on an innovative, broadband multibeam antenna, proposed for satellite communications by the Institute of Electronics and Telecommunications of Rennes (IETR), in the framework of a collaborative research with the French Space Agency (Centre National d'Iitudes Spatiales). The antenna comprises an array of long slots, parallelfed by a corporate feed network of parallel plate waveguides. An integrated quasi-optical beamformer, illuminated by a single horn or by a focal array of horns, excites the feed network. The beam scanning can be achieved both mechanically and electronically. The numerical models developed for the analysis and design are reviewed. The experimental results presented for a Ka-band design demonstrates the wideband, wide-angle scanning performance of the proposed architecture. Finally, future research lines for achieving circular polarization are projected. The proposed antenna concept is particularly suitable for high throughput ground terminals on moving platforms.