12/21GHz dual-band feed for circularly polarized satellite broadcasting receiving antenna

The 21GHz band satellite broadcasting system is studied for transmission channels to deliver ultra high definition TV, 3D television and so on. A 12/21GHz dual-band parabolic reflector antenna will enable to receive TV services using different frequency bands with a single reflector antenna. To achieve sufficient gain for TV reception in both bands, a 12/21GHz dual-band feed is designed for the parabolic antenna with a circularly polarized microstrip array antenna. The feed is designed in terms of the voltage standing wave ratio (VSWR) and the radiation pattern. Simulation results show that the VSWR was less than 1.5 throughout the target range in both bands and that the beamwidth of the radiation pattern was the same for both bands.