Design of compact hybrid profiled corrugated feed horn for SATCOM C band

This paper presents the design, development and simulation results of a C-band profiled corrugated feed horn. The corrugations are radially cut in the horn surface. Ring-loaded mode converters are used for significant reduction in feed aperture and desirable increase in bandwidth thereby giving many advantages in overall reflector systems. The horn flare is profiled so that the inner surface of horn is having a curvilinear flare. This approach has led to significant reduction in overall size of the feed. Stow height of VSAT systems is reduced and the blockage area by the feed in dual reflector systems is decreased as well. Though the feed is designed to work in the SATCOM operating frequency range i.e. from 3.4 to 6.725 GHz, but the feed results are better beyond these frequencies. The return loss over the band (3.4-8 GHz) is greater than 20 dB. On axis cross-polarization levels are better than 55 dB (3.4-7 GHz).Furthermore, radiation pattern symmetricity is maintained in orthogonal planes. This feed horn finds application in VSAT, Earth station antennas and SOTM (Satcom on the Move) systems.