Waveguide termination arrangements for array antennas

Abstract

An array antenna () having a layered configuration. The array antenna comprises a radiation layer () comprising a plurality of radiation elements () and a distribution layer () facing the radiation layer. The distribution layer is arranged to distribute a radio frequency, RF, signal to the plurality of radiation elements. The distribution layer comprises at least one distribution layer feed () and at least one first waveguide () arranged to guide the RF signal between at least one distribution layer feed and at least one radiation element. The array antenna further comprises at least a second waveguide () connected to at least one distribution layer feed (). Any of the first () and the second () waveguides comprises plastics with a first type of surface treatment (), where the first type of surface treatment comprising metallization. At least one radiation element is a dummy element terminated by an attenuation section, where the attenuation section is arranged on any of the waveguides () connected to the dummy element and that comprises plastics. The attenuation section comprises a second type of surface treatment () arranged to attenuate the RF signal.