摘要:
When a converter 14 is rotated via a rotation mechanism 17, the arrangement inclination angle of two primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. with respect to an axis which is in parallel with the ground. Also the reception polarization angle due to probes of the primary radiators 15a and 15b can be adjusted in the range of 0 to 20 deg. while maintaining a preset difference in polarization angle among the satellites. Therefore, the arrangement inclination angle of the primary radiators 15a and 15b for respectively receiving signals from the two satellites, and the reception polarization angle in the primary radiators 15a and 15b can be simultaneously easily adjusted by rotating the converter 14 via the rotation mechanism 17.
摘要:
A grid-type microwave antenna, easy to manufacture, assemble and disassemble, is formed of a number of spaced reflector rods which, when mounted in a frame, form a parabolic reflecting surface. The frame includes U-shaped channels for mounting and supporting the spaced reflector rods. Each of the rods has a curvature so that the combination of the rods spanning the frame forms a parabolic reflector. The frame is formed by channels having holes to receive the central and the end portions of the reflector rods. Insulating sleeves are provided for the central portion of each rod. Insulating cups are used for the end portions of each rod.
摘要:
A multi-beam antenna for receiving microwaves emanating from at least first and second satellites comprising: a reflector which has a cylindro-paraboloidal shape (2) arranged substantially in the vertical plane and capable of focusing the incident microwaves on a substantially horizontal focal straight line (D) constructed from the foci (F1 to F5) of the reflector, at least first and second linear networks (R1, R2) being distributed substantially horizontally in the focal plane of the reflector, in order to receive and process, according to first and second laws of amplitude and time-lag, the incident microwaves emanating from first and second directions corresponding to the first and second satellites.
摘要:
There is disclosed a flexible fabric cover for an off-axis parabolic satellite antenna dish having a front surface which serves to cover and protect the front of the antenna dish and the receiver arm; the cover is preferably formed of a generally elliptical sheet of woven synthetic fabric which is at least moderately stretchable, which is about six inches greater in diameter than the antenna dishes it is intended to cover, and which has a central aperture or pocket for the antenna receiver support arm whereby the cover assumes a generally conical, slightly truncated shape; the cover includes securing means in the preferred embodiment consisting of a peripheral hem having threaded therein a drawstring or drawcord such that the cover may be placed over the front of the antenna dish with drawstring relaxed and the drawstring then tightened by employment of a conventional tightening device capturing the rim of the dish with the hem to fasten the cover tightly and smoothly over the dish and the receiver support arm. In one embodiment, the sheet comprises three sections generally in the shape of sectors of an ellipse with an angle of about 45.degree. and one section of generally rectangular shape positionable over the receiver support arm.
摘要:
A multibeam antenna for simultaneously receiving waves from one or more communication satellites and a broadcast satellite, which are apart in their stationary orbit positions over the equator, is disclosed. The antenna employs an offset parabolic face, used as a reflector for receiving satellite broadcast waves, a converter having a primary radiator for receiving communication satellite Waves set at the focus point of the offset parabolic face, and a converter having a primary radiator for receiving broadcast satellite waves set near the envelope of the broadcast waves reflected from the offset parabolic face. The offset parabolic face is pointed in the direction of the communication satellite such that the plane of symmetry of the offset parabolic face is coincident with a plane specified by the communication satellite, the broadcast satellite, and the receiving point of the antenna. By utilizing this arrangement, an antenna that is relatively inexpensive to manufacture and is easily installable and adjustable may be obtained.
摘要:
A single offset reflector antenna is disclosed which provides .+-.30.degree. of horizontal scanning and 0.degree. to +15.degree. of vertical scanning without aperture blockage, while maintaining high aperture efficiency, and 0.degree. to -30.degree. of vertical scanning with moderate aperture blockage. The sufrace of the reflector antenna is described by a sixth order polynomial equation. Curvature of the horizontal cross-section of the surface taken through its center is determined by a fourth order even polynomial expression with coefficients that are found by a numerical minimization technique. Further terms, including terms of up to sixth order and their associated coefficients obtained by the numerical minimization technique, define the curvature of the vertical cross-sections of the surface to yield a three-dimensional unitary reflecting surface.
摘要:
A microwave integrated apparatus, particularly useful for a satellite broadcasting receiver, comprises a housing having a radiation aperture and being electromagnetically shielded except for the radiation aperture. An insulated substrate is disposed in the housing, and has formed thereon an antenna pattern capable of receiving or radiating microwaves through the radiation aperture of the housing. A signal-processing means is disposed beside the insulated substrate in the housing, and is connected to the antenna pattern on the insulated substrate. For achieving a microwave circuit arrangement having excellent performance characteristic of a very wide frequency range, a second antenna pattern is disposed at the radiation aperture of the housing, and in proximity to the above-mentioned antenna pattern.
摘要:
A reflector-type microwave antenna includes a paraboloidal reflector and a feed horn located at the focal point of the reflector for launching microwave signals onto the reflector and receiving microwave signals from the reflector. A supporting frame for the reflector and feed horn includes three arms extending along the rear side of the reflector to three spaced mounting locations on the rear side of the reflector. The arms are fastened to the spaced mounting locations on the rear side of the reflector by fastening means having a loose condition in which the arm is attached to the reflector but free to move relative to the reflector, and a tightened condition in which the respective arm is rigidly attached to the reflector. The fastening also includes swivel means for permitting tilting movement of the arm relative to the reflector surface when the fastening means is in the loose condition, and permitting the arm to assume different positions relative to the reflector when the fastening means is in the tightened condition. In its preferred form, the fastening means includes a cupped member having a peripheral flange secured to the rear side of the reflector so that forces transmitted between the respective arms and the reflector are distributed over the area of the reflector encompassed by the flanges.
摘要:
Disclosed is an antenna device, which comprises a reflector and a primary radiator for an ARSR system including a low beam horn antenna disposed at a position substantially at the focal point of the reflector and a high beam horn antenna disposed below the low beam horn antenna. The antenna device further comprises a primary radiator for an SSR system including two modified diagonal horns provided on opposite sides of and having outside perimeters complementary to the arrangement of the low and high beam horn antennas and at positions corresponding to a position midway between the low and high beam horn antennas. A Yagi antenna used as a part of the SSR radiator, is disposed above the low beam horn antenna. Thus, the antenna device can be used commonly for both the ARSR and SSR systems.
摘要:
A lightweight inexpensive fiberglass antenna dish is disclosed, as well as a method for the manufacture thereof. The dish may be formed by spraying chopped fiberglass and epoxy binder onto the glazed surface of a parabolic mold. An aperture formed on the focal axis of the antenna dish, either at the time of molding or at a later time, accommodates a heavy wall structural tube which extends along the focal axis half-way towards the focal point and which is secured to the dish. Rods secured between the dish surface and the distal end of the tube form triangular shapes in cross-section which rigidify the dish element. The feed unit, such as a horn, is attached to the distal end of the tube and the transmission lines therefore can pass through the tube itself.