A circularly polarized waveguide array for LEO satellite communications

The development of a low profile, circularly polarized waveguide array for LEO satellite communications is presented. Due to the large number of spacecraft forming the LEO constellation, the design of such an array requires a low cost approach. The array operates from 12.95 to 14.50 GHz and is designed to have an active match of better than 25 dB across the band. The array is fed by a compact reactive waveguide beamforming network, which dictates the need for well-matched radiating elements. To provide beam zooming capability, the element excitations are controlled to generate different orbit location dependent beams. Circular polarization is achieved by means of a meander-line polarizer. Design and test of this antenna are discussed.