An antenna may include a reflector and a multi-band feed assembly. A support member may be coupled to the multi-band feed assembly to orient the multi-band feed assembly for direct illumination of the reflector. The multi-band feed assembly may include first and second feeds, each having a respective septum polarizer coupled between a respective common waveguide and a respective pair of waveguides. A housing of the support member may contain the respective septum polarizers and the respective pairs of waveguides.

A parallel-plate diplexer includes a first parallel-plate transmission line and a second parallel-plate transmission line, a first end of the second parallel-plate transmission line including a first port and a second end of the second parallel-plate transmission line including a second port, and a first end of the first parallel-plate transmission line including a third port and a second end of the first parallel-plate transmission line being coupled to the second parallel-plate transmission line at a T-junction between the first port and the second port. The second parallel-plate transmission line includes a first parallel-plate transmission line tuning network located between the T-junction and the first port, and a second parallel-plate transmission line tuning network located between the T-junction and the second port.

Embodiments of the invention include an integrated monopulse comparator assembly for use in tracking antenna applications such as an antenna feed or an antenna array. Embodiments of the monopulse comparator assembly may include four rectangular waveguide antenna inputs, four magic tees, rectangular waveguide connections, and four rectangular waveguide monopulse outputs. An embodiment of a 44 antenna array including an embodiment of an integrated monopulse comparator assembly is also disclosed.

A waveguide disclosed herein may be implemented as a hollow irregular hexagonal metal structure which receives an electromagnetic signal and propagates the signal through the hollow hexagonal metal structure. The waveguide may be fabricated using metal additive manufacturing techniques and include one or more downward facing and unsupported surfaces.

A waveguide circuit (1) includes a first waveguide tube (10), a second waveguide tube (20), and a third waveguide tube (30). The first waveguide tube (10), the second waveguide tube (20), and the third waveguide tube (30) have cross-sectional shapes to allow propagation of TE modes. The tube axis of the second waveguide tube (20) is parallel to the tube axis of the first waveguide tube (10). One of the narrow sidewalls of the second waveguide tube (20) faces a narrow sidewall (10s) of the first waveguide tube (10). The third waveguide tube (30) includes a coupler that connects a hollow guide of the third waveguide tube (30) to a hollow guide of the first waveguide tube (10) and a hollow guide of the second waveguide tube (20).

A waveguide device includes: an electrically conductive member having an electrically conductive surface; a waveguide member having an electrically-conductive waveguide face of a stripe shape opposing the electrically conductive surface, the waveguide member extending along the electrically conductive surface; and an artificial magnetic conductor extending on both sides of the waveguide member. The waveguide member has a bend at which the direction that the waveguide member extends changes. A waveguide which is defined by the electrically conductive surface, the waveguide face, and the artificial magnetic conductor includes a gap enlargement where a gap between the electrically conductive surface and the waveguide face is locally increased. In a perspective view along a direction perpendicular to the electrically conductive surface, at least a portion of the bend has an overlap with the gap enlargement.

The present invention reduces the risk of damaging a waveguide made of a brittle material. A transmission line (1) includes: a first waveguide (11) which is made of a brittle material; a second waveguide (21); and a bonding layer (31) by which the first waveguide (11) and the second waveguide (21) are bonded and which is electrically conductive. At least part of the bonding layer (31) is made of an electrically conductive adhesive, the at least part of the bonding layer (31) being in contact with the first waveguide (11).

An antenna may include a reflector and a multi-band feed assembly. A support member may be coupled to the multi-band feed assembly to orient the multi-band feed assembly for direct illumination of the reflector. The multi-band feed assembly may include first and second feeds, each having a respective septum polarizer coupled between a respective common waveguide and a respective pair of waveguides. A housing of the support member may contain the respective septum polarizers and the respective pairs of waveguides.

A parallel-plate diplexer includes a first parallel-plate transmission line and a second parallel-plate transmission line, a first end of the second parallel-plate transmission line including a first port and a second end of the second parallel-plate transmission line including a second port, and a first end of the first parallel-plate transmission line including a third port and a second end of the first parallel-plate transmission line being coupled to the second parallel-plate transmission line at a T-junction between the first port and the second port. The second parallel-plate transmission line includes a first parallel-plate transmission line tuning network located between the T-junction and the first port, and a second parallel-plate transmission line tuning network located between the T-junction and the second port.

A waveguide-to-parallel-plate twist transition includes at least one waveguide-to-parallel plate twist transition element comprising an input port comprising an input waveguide portion, the input waveguide portion configured to orient an E-field of an electromagnetic wave along a first plane, and an output port comprising a multi-mode parallel plate portion, the multi-mode parallel plate portion configured to orient an E-field of an electromagnetic wave along a second plane, wherein an angle of orientation of the second plane is different from an angle of orientation of the first plane. The twist transition further includes at least one intermediate discrete twist waveguide stage coupling each input waveguide portion to the output multi-mode parallel plate portion, wherein at least one intermediate discrete twist waveguide stage is configured to orient an E-field of an electromagnetic wave along a third plane, wherein an angle of orientation of the third plane is between the angle of orientation of the first plane and the angle of orientation of the second plane