A planar array antenna for TV broadcasting communications

The L-Sat planar array for satellite direct TV broadcasting is described. Still in the design stage, the array is intended for broadcasting on the X-band, within the 0.98 x 2.3 deg elliptical beam, sidelobe below -30 dB, circular polarization with low cross-polarization WARC requirements. The results of an analysis of the effects produced by the contour profile on the radiation pattern are presented. Further work has proceeded on a circuit model of a slot in a single subarray, the coupling of mutual slots, and the phase and amplitude behhavior of the coupled feeding and radiating waveguides. Finally, simulations have been performed of the thermally induced deformations, with attention given to warping and a tilted half-plane.