US Patent 9634400 Dish antenna having a self-supporting sub-reflector assembly

An antenna has a waveguide horn extending from a main reflector. A dielectric tube extends from the distal end of the waveguide horn to support a sub-reflector in the focal region of the main reflector. An insert is placed into the dielectric tube to seat against the distal end of the dielectric tube. A fastener secures the insert to the sub-reflector, thereby securing the sub-reflector to the distal end of the dielectric tube. The surface of the insert serves as a continuation of the sub-reflector. The dielectric tube can be equipped with an inwardly-extending collar about its distal end to engage the insert.