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 reflector antenna device includes: an auxiliary reflector 1 that receives an electric wave radiated from an opening portion by a primary radiator 3 and reflects the electric wave; and a main reflector 2 that receives the electric wave that is reflected by the auxiliary reflector 1 and radiates the electric wave to a space. In the reflector antenna device, the configurations of the auxiliary reflector 1 and the main reflector 2 are designed such that an electric power in an area of the main reflector 2 where the auxiliary reflector 1 is projected on the main reflector 2 in parallel with the radiating direction of the electric wave due to the main reflector 2 is equal 1 or lower than a predetermined first threshold value, and a radiation pattern of the antenna which is determined by the area of the main reflector 2 other than the area has a desired characteristic.

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: An antenna device, a radio communication terminal, an external antenna, and a hand strap can be provided, which are capable of ensuring satisfactory communication performance without being affected by the surrounding environment even in an area where the electric field is weak, and having the antenna performance improved by slightly modifying the body of an existing radio communication device. The antenna device according to the present invention includes an internal antenna (2) electrically connected to and incorporated into a circuit for radio communication within a case (1) and an external antenna (3) externally attached to the case.

Abstract: Disclosed is an image capturing apparatus comprising a primary mirror 1 that has a surface which is a section of a surface cut out from a paraboloid with a single focus; a secondary mirror 2 that has a surface which is a section of a surface cut out from a hyperboloid with two foci; and a photodetector 3 which converts the light signal coming from the secondary mirror 2 into an electric signal. The secondary mirror 2 is placed in a position where one of its foci and the focus of the primary mirror 1 match with each other. The photodetector 3 is placed near the other focus of the secondary mirror 2. By using two mirrors, the light from the object is led to the photodetector 3 without being shaded.

Abstract: A reflector antenna device includes: an auxiliary reflector 1 that receives an electric wave radiated from an opening portion by a primary radiator 3 and reflects the electric wave; and a main reflector 2 that receives the electric wave that is reflected by the auxiliary reflector 1 and radiates the electric wave to a space. In the reflector antenna device, the configurations of the auxiliary reflector 1 and the main reflector 2 are designed such that an electric power in an area of the main reflector 2 where the auxiliary reflector 1 is projected on the main reflector 2 in parallel with the radiating direction of the electric wave due to the main reflector 2 is equal 1 or lower than a predetermined first threshold value, and a radiation pattern of the antenna which is determined by the area of the main reflector 2 other than the area has a desired characteristic.

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: An antenna device, a radio communication terminal, an external antenna, and a hand strap can be provided, which are capable of ensuring satisfactory communication performance without being affected by the surrounding environment even in an area where the electric field is weak, and having the antenna performance improved by slightly modifying the body of an existing radio communication device. The antenna device according to the present invention includes an internal antenna (2) electrically connected to and incorporated into a circuit for radio communication within a case (1) and an external antenna (3) externally attached to the case.

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.

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.

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: An antenna mirror surface measuring/adjusting apparatus has a plane mirror larger than an aperture surface of said principal reflection mirror and set in parallel with the aperture surface, an actuator for driving a group of mirror surface panels of the principal reflection mirror, and a receiving electric field arithmetic processor for measuring, each time the actuator shifts a position of the mirror surface panel from an initial state of the mirror surface panel of the principal reflection mirror, radio wave signals of radio waves radiated by a transmitter/receiver and reflected back from the plane mirror, obtaining an aperture surface phase distribution in an initial state of the principal reflection mirror by executing an arithmetic process on these measured signals, then gaining configurations of the mirror surface on the basis of the aperture surface phase distribution, and adjusting the mirror surface by the actuator in accordance with the obtained mirror surface configurations.

Abstract: An antenna system in which primary radiators are disposed on the radiation side of beams from a main reflector and in opposition to a subreflector and in which the subreflector and the primary radiators are disposed in positions offset from beam blocking positions.

Abstract: In a reflecting mirror antenna unit, the surface of the reflecting mirror is divided into a plurality of parts, and the parts are made different in thickness from one another, for instance, by bonding metal tapes different in thickness thereto, to change the phase distribution on the reflecting mirror, whereby the configuration of the radiation pattern due to the current distribution on the reflecting mirror is readily changed.