Abstract: A disk-shaped reflecting plate 3 for reflecting an electric wave emitted out of an aperture 1a of a circular waveguide 1 is placed a location which is just opposite to the aperture 1a of the circular waveguide 1, and a ring-shaped waveguide 4 for shaping the radiation characteristic of the electric wave reflected by the disk-shaped reflecting plate 3 to a rotational symmetrical radiation characteristic is disposed around the perimeter of the disk-shaped reflecting plate 3. Thereby, even when many grooves 4a need to be formed in order to make the electric wave have a rotational symmetrical radiation characteristic, it is not necessary to increase the size of the disk-shaped reflecting plate 3 in the direction of its radius.

Abstract: An antenna apparatus in which a combination of rectangular waveguides 9a and 10a and a combination of rectangular waveguides 9b and 10b are disposed bilateral symmetrically to each other, and a waveguide orthomode transducer 13 is disposed above a waveguide orthomode transducer 8 is provided. Therefore, the profile of the antenna apparatus can be reduced and the stability of installation of the antenna apparatus can be improved without impairing the electric characteristics of the antenna apparatus. Since the antenna apparatus has a bilateral symmetric structure, it excels in weight balance and offers stable performance from the viewpoint of mechanism.

Abstract: The present invention aims at providing a rotary joint which is of a thin type and has broad band characteristics and which is low in loss and is excellent in power resistance as well. In order to attain the object, the rotary joint includes: first and second polarizers each having a common side terminal connected to a waveguide portion, and two branch side terminals through which two polarized waves orthogonal to each other inputted through the common side terminal are separately taken out; and the waveguide portion which has a rotatable connection portion, one end of which is connected to the common side terminal of the first polarizer and the other end of which is connected to the common side terminal of the second polarizer.

Abstract: The present invention includes: a first main waveguide 1; a T-branch circuit 3 connected thereto; a first low-pass filter 5 connected thereto; a band-pass filter 7 connected to the first T-branch circuit 3; a first converter 8 connected to the first low-pass filter 5 for converting transmission lines between a waveguide and a microwave integrated circuit; an amplifier 10 connected to the first converter and structured by the microwave integrated circuit; a second converter 9 connected thereto for converting transmission lines between a waveguide and the microwave integrated circuit; a second low-pass filter 6 connected thereto; a second T-branch circuit 4 connected to the second low-pass filter and the band-pass filter 7; and a second main waveguide 2 connected to the second T-branch circuit.

Abstract: An object of the present invention is to obtain a waveguide type polarizer, which enables miniaturization thereof, shortening of an axis, and broad band promotion, and which has high performance. In order to attain the object, the waveguide type polarizer includes: a first rectangular main waveguide 1; first to fourth rectangular branching waveguides 2a to 2d branching perpendicularly to the first rectangular main waveguide 1; a short-circuit plate 3 connected to one terminal of the first rectangular main waveguide 1; a metallic block 4 provided on the short-circuit plate 3; a rectangular waveguide step 5 connected to the other terminal of the first rectangular main waveguide 1; and a second rectangular main waveguide 6 connected to the rectangular waveguide step 5.

Abstract: A nonreflective waveguide terminator includes a waveguide portion and an electromagnetic wave absorber. The portion has a rectangular opening in a plane perpendicular to a radio-wave propagation direction. The portion has one open end in the direction and the other end closed by a terminating metal internal wall. The portion has a radio-wave propagation space surrounded by first and second metal internal walls parallel to a radio-wave electric field, and third and fourth metal internal walls perpendicular to the field. The exterior shape of the absorber is a parallelepiped. The absorber has a rear-end surface positioned at a predetermined distance from the terminating wall and parallel to the terminating wall or is provided against the terminating wall. The surface of the absorber having the largest rectangular area is on the third or the fourth metal internal wall.

Abstract: A waveguide unit including a vertically polarized waveguide, a horizontally polarized waveguide, and a waveguide type-polarized wave converter interposed between said waveguides. The waveguide type-polarized wave converter has a slit, the shape of which being combination of two quadrate parts and a connecting part for connecting the two quadrate parts. Those polarized waveguides and polarized wave converter are integrally manufactured but can be divided into two parts.

Abstract: An antenna apparatus in which a combination of rectangular waveguides 9a and 10a and a combination of rectangular waveguides 9b and 10b are disposed bilateral symmetrically to each other, and a waveguide orthomode transducer 13 is disposed above a waveguide orthomode transducer 8 is provided. Therefore, the profile of the antenna apparatus can be reduced and the stability of installation of the antenna apparatus can be improved without impairing the electric characteristics of the antenna apparatus. Since the antenna apparatus has a bilateral symmetric structure, it excels in weight balance and offers stable performance from the viewpoint of mechanism.

Abstract: A waveguide orthomode transducer includes a first radio wave conducting means for conducting an electric wave of a horizontally polarized wave branched by an electric wave branch means, for conducting another electric wave of the horizontally polarized wave, for combining the electric waves of the horizontally polarized wave into one electric wave and dividing this electric wave into an electric wave of a basic mode and an electric wave of a higher mode, and for outputting them, and a second radio wave conducting means for conducting one electric wave of a vertically polarized wave branched by the electric wave branch means, for conducting another electric wave of the vertically polarized wave, for combining the electric waves of the vertically polarized wave into one electric wave and dividing this electric wave into an electric wave of a basic mode and an electric wave of a higher mode, and for outputting them.

Abstract: The present invention includes: a first main waveguide 1; a T-branch circuit 3 connected thereto; a first low-pass filter 5 connected thereto; a band-pass filter 7 connected to the first T-branch circuit 3; a first converter 8 connected to the first low-pass filter 5 for converting transmission lines between a waveguide and a microwave integrated circuit; an amplifier 10 connected to the first converter and structured by the microwave integrated circuit; a second converter 9 connected thereto for converting transmission lines between a waveguide and the microwave integrated circuit; a second low-pass filter 6 connected thereto; a second T-branch circuit 4 connected to the second low-pass filter and the band-pass filter 7; and a second main waveguide 2 connected to the second T-branch circuit.

Abstract: For the purpose of obtaining a mechanical drive reflecting mirror antenna device which is downsized and low in attitude, enables wide-angle scanning, and is high in performance, there are provided a main reflection mirror 1, a sub-reflection mirror 2, a primary radiator 3, a first circular waveguide 4 which is connected to the primary radiator and has a plurality of bend portions, a first circular waveguide rotary joint 5 which is connected to the first circular waveguide, a second circular waveguide 7 which is connected to the first circular waveguide rotary joint and has a plurality of bend portions, and a second circular waveguide rotary joint 8 which is connected to the second circular waveguide and is different in a direction of a rotary axis from the first circular waveguide rotary joint by substantially 90 degrees.

Abstract: A nonreflective waveguide terminator includes a waveguide portion and an electromagnetic wave absorber. The portion has a rectangular opening in a plane perpendicular to a radio-wave propagation direction. The portion has one open end in the direction and the other end closed by a terminating metal internal wall. The portion has a radio-wave propagation space surrounded by first and second metal internal walls parallel to a radio-wave electric field, and third and fourth metal internal walls perpendicular to the field. The exterior shape of the absorber is a parallelepiped. The absorber has a rear-end surface positioned at a predetermined distance from the terminating wall and parallel to the terminating wall or is provided against the terminating wall. The surface of the absorber having the largest rectangular area is on the third or the fourth metal internal wall.

Abstract: The waveguide group branching filter according to the present invention is formed by boring out of two metal blocks constituent circuits including a circular-to-square waveguide multistage transformer 1, the branch waveguide polarizer/branching filter 4, a rectangular waveguide multistage transform 9, the rectangular waveguide H-plane T-branch circuit 10, and waveguide band-pass filters 8, 14 and 18; radio waves V1 and H1, which have their polarization planes vertical and horizontal, respectively, to the branching plane of the branch waveguide polarizer/branching filter 4 in a certain frequency band f1, and a radio wave V2 of the same polarization plane as that of the radio wave V1 in a frequency band f2 higher than the frequency band f1 are incident to an input port P1, and the radio wave V1 is emitted from an output port P2, the radio wave H1 from an output port P3 and the radio wave V2 from an output port P4.

Abstract: A waveguide unit including a vertically polarized waveguide, a horizontally polarized waveguide, and a waveguide type-polarized wave converter interposed between said waveguides. The waveguide type-polarized wave converter has a slit, the shape of which being combination of two quadrate parts and a connecting part for connecting the two quadrate parts. Those polarized waveguides and polarized wave converter are integrally manufactured but can be divided into two parts.

Abstract: An object of the present invention is to obtain a waveguide type polarizer, which enables miniaturization thereof, shortening of an axis, and broad band promotion, and which has high performance. In order to attain the object, the waveguide type polarizer includes: a first rectangular main waveguide 1; first to fourth rectangular branching waveguides 2a to 2d branching perpendicularly to the first rectangular main waveguide 1; a short-circuit plate 3 connected to one terminal of the first rectangular main waveguide 1; a metallic block 4 provided on the short-circuit plate 3; a rectangular waveguide step 5 connected to the other terminal of the first rectangular main waveguide 1; and a second rectangular main waveguide 6 connected to the rectangular waveguide step 5.

Abstract: The present invention aims at providing a rotary joint which is of a thin type and has broad band characteristics and which is low in loss and is excellent in power resistance as well. In order to attain the object, the rotary joint includes: first and second polarizers each having a common side terminal connected to a waveguide portion, and two branch side terminals through which two polarized waves orthogonal to each other inputted through the common side terminal are separately taken out; and the waveguide portion which has a rotatable connection portion, one end of which is connected to the common side terminal of the first polarizer and the other end of which is connected to the common side terminal of the second polarizer.

Abstract: In order to provide a reflector antenna apparatus which can be installed within a small space, which has adequate practicality, and which can perform scanning by pivoting about two axes which are perpendicular to each other, in a reflector antenna apparatus having a Cassegrain reflector and a rotating mechanism which rotates the reflector about an azimuth axis and an elevation axis, a reflector with a substantially rectangular aperture has its elevation axis passing through substantially the central portion of the height dimension of the reflector, and reflector surface adjustment is carried out such that substantially all of the electromagnetic waves which are supplied are received and reflected, whereby the antenna height does not become large when the reflector rotates about the elevation axis. The reflector may be an array of a plurality of reflector elements.