An experimental investigation of wide-angle sidelobe suppression in a pyramidal horn-reflector antenna

An experimental investigation into the suppression of wide-angle radiation from a pyramidal horn-reflector antenna is reported in this study. We show that lining the sidewalls or diffracting edges of this antenna with microwave absorber in the region of the visible aperture can lead to a marked reduction in sidelobe energy when the antenna is transversely polarized. Specifically, sidelobe reductions of as much as 10 dB are attainable over angular regions 40 degrees or more from the main beam. Though the described absorber treatment reduces wide-angle radiation, it can simultaneously increase and distinctly modify the character of near-in sidelobe structure. Data reported in this study are related to those of a recently published paper on selective near-in sidelobe reduction for a pyramidal horn-reflector antenna.