Super-Open-Boundary quadridge horn antennas

The present work shows the concept of the open boundary quadridge horn (OBQH) introduced in 2005 [1] now scaled to lower frequencies. The concept has been taken to extremes by also opening the feed cavity of the horn leaving a fully unbounded antenna. The resulting antenna, although large in size, offers excellent VSWR and gain. The antenna is designed to perform both as a standalone unit or mounted to the wall of a chamber nested in the absorber treatment. In addition to the antenna introduced in [2] a secondary antenna operating over a higher frequency range is also introduced.