A radio frequency load for absorbing a radio frequency wave having a frequency in a predetermined frequency band and a wavelength comprises a waveguide with a portion having an opening for said radio frequency wave. In addition, the radio frequency load comprises at least one metal rod provided in said waveguide, said at least one metal rod having a length of one-half of said wavelength to damp said radio frequency wave.

One or more load cells, for one or more corresponding radio-frequency waveguide terminations are provided. The load cells are integral with the structure by which they are to be fixed to the one or more waveguide terminations. Corresponding manufacturing methods are disclosed.

One or more load cells, for one or more corresponding radio-frequency waveguide terminations are provided. The load cells are integral with the structure by which they are to be fixed to the one or more waveguide terminations. Corresponding manufacturing methods are disclosed.

Disclosed is a system for measuring the power of a microwave beam. The system includes a waveguide, a preload, a load, a diffusing mirror disposed inside the load, cooling conduits containing water lapping the against load, a thermometer for measuring the temperature of the water, and calculation means for calculating the power of the microwave beam based on a temperature increase of the water. Wherein the preload has a deviation box with a beam deviator configured in such a way to allow for a deviation and collimation of a microwave beam exiting the deviation box with respect to a microwave beam entering the deviation box.

An array antenna (100) having a layered configuration. The array antenna comprises a radiation layer (110) comprising a plurality of radiation elements (111) and a distribution layer (120) 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 (121) and at least one first waveguide (122) 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 (130) connected to at least one distribution layer feed (121). Any of the first (122) and the second (130) waveguides comprises plastics with a first type of surface treatment (313), 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 (122, 130) connected to the dummy element and that comprises plastics. The attenuation section comprises a second type of surface treatment (314) arranged to attenuate the RF signal.