A waveguide in the form of a wave duct for transmitting microwave signals includes at least one non-conducting body arranged in and/or on the wave duct, and by at least one MHD pump, by which an electrically conductive liquid medium can be admitted to fill the at least one body and/or to exert a force on at least one wall of the wave duct.

A waveguide in the form of a wave duct for transmitting microwave signals includes at least one non-conducting body arranged in and/or on the wave duct, and by at least one MHD pump, by which an electrically conductive liquid medium can be admitted to fill the at least one body and/or to exert a force on at least one wall of the wave duct.

A radiating element is provided, for example for array antenna, having stacked resonant cavities of Pérot-Fabry type, of compact structure, a lower cavity being fed by excitation means, the radiating element being characterized in that corrugations are formed substantially below a first earth plane delimiting in its lower part the upper resonant cavity. A radiating element structure of improved compactness is also proposed, whose upper cavity is surmounted by a polarizing radome.

A radiating element is provided, for example for array antenna, having stacked resonant cavities of Pérot-Fabry type, of compact structure, a lower cavity being fed by excitation means, the radiating element being characterized in that corrugations are formed substantially below a first earth plane delimiting in its lower part the upper resonant cavity. A radiating element structure of improved compactness is also proposed, whose upper cavity is surmounted by a polarizing radome.

An antenna device includes: antennas; magnetic oscillation element units converting electrical energy to high-frequency power, and a modulator outputting electrical energy input from outside to at least two magnetic oscillation element units, with a time difference to differentiate phases of high-frequency power converted from electrical energy by at least two magnetic oscillation element units. The magnetic oscillation element units respectively include a pair of electrodes, and further include, between the pair of electrodes, a PIN layer, a free layer, and an intermediate layer. A resistance value of an element configured by the PIN, free and intermediate layers changes according to the angle between the magnetization direction of the PIN layer and the magnetization direction of the free layer. The antennas transmit electromagnetic waves to open space outside the magnetic oscillation element units with the supply of high-frequency power.

An antenna device includes: antennas; magnetic oscillation element units converting electrical energy to high-frequency power, and a modulator outputting electrical energy input from outside to at least two magnetic oscillation element units, with a time difference to differentiate phases of high-frequency power converted from electrical energy by at least two magnetic oscillation element units. The magnetic oscillation element units respectively include a pair of electrodes, and further include, between the pair of electrodes, a PIN layer, a free layer, and an intermediate layer. A resistance value of an element configured by the PIN, free and intermediate layers changes according to the angle between the magnetization direction of the PIN layer and the magnetization direction of the free layer. The antennas transmit electromagnetic waves to open space outside the magnetic oscillation element units with the supply of high-frequency power.

A surface-wave waveguide may include a base conductive ground plane including opposite side edges and a pair of conductive side walls. One conductive side wall extends from each side edge of the conductive ground plane. The surface-wave waveguide may also include a substrate including a dielectric material disposed on the base conductive ground plane and between the conductive side walls. The surface-wave waveguide may also include an impedance sheet disposed on the substrate and between the conductive side walls. The impedance sheet may include a predetermined impedance characteristic for transmitting an electromagnetic wave.

A surface-wave waveguide may include a base conductive ground plane including opposite side edges and a pair of conductive side walls. One conductive side wall extends from each side edge of the conductive ground plane. The surface-wave waveguide may also include a substrate including a dielectric material disposed on the base conductive ground plane and between the conductive side walls. The surface-wave waveguide may also include an impedance sheet disposed on the substrate and between the conductive side walls. The impedance sheet may include a predetermined impedance characteristic for transmitting an electromagnetic wave.

In one embodiment, a sub-reflector assembly for a reflector antenna has (i) a waveguide transition at a waveguide end of the sub-reflector assembly and configured to fit within a waveguide, (ii) a dielectric radiator connected to the waveguide transition and extending both laterally and back towards the waveguide end of the sub-reflector assembly, and (iii) a sub-reflector connected to the dielectric radiator. By configuring the dielectric radiator to extend both laterally and back towards the dielectric end of the assembly, radiated energy from the waveguide is directed such that the sub-reflector assembly can be used with shallow reflector dishes (e.g., F/D ratio greater than 0.25) and still achieve sufficiently high directivity.

A method and apparatus is presented. A structure having an interior channel is formed using additive manufacturing equipment. A viscous media containing abrasive particles is sent through the interior channel using abrasive flow machining equipment to form a desired surface roughness for the interior channel.