RU2383976C1 - Mirror antenna - Google Patents

Abstract

FIELD: physics; radio.

SUBSTANCE: invention relates to antenna equipment used in the decimetre and centimetre wavelength range. The mirror antenna has a radiating device which includes two radiators mounted on a single bearing structure with orthogonal polarisations, one of which is the low wavelength band and the other - the high wavelength band. The mirror antenna has two parabolic reflecting surfaces formed by parallel linear elements. Linear elements of one parabolic surface are directed orthogonally relative linear elements of the other parabolic surface. The focus of one parabolic surface is superimposed with the phase centre of the low band radiator and the focus of the other parabolic surface is superimposed with the phase centre of the high band radiator. The antenna works in two wavelength bands at the same time in a single direction.

EFFECT: maximum decoupling, improved noise immunity, increased coefficient of amplification and directivity.

5 cl, 4 dwg

Description

FIELD OF THE INVENTION

The invention relates to radio engineering and can be used in transceiver equipment of decimeter and centimeter wavelength ranges.

State of the art

A known design of a parabolic antenna (see the description of the invention to patent RU No. 2168817, IPC H01Q 3/06, publ. 06/10/2001), including a parabolic mirror and an irradiator installed in its aperture from two semicircular mutually orthogonal frames mounted vertically on a round flat screen a form mounted on a tubular support located on the axis of the parabolic mirror.

The main disadvantage of the above design is the shading of the mirror surface by the irradiator. However, the antenna according to patent No. 2188817 is a narrow-band antenna and cannot operate in two wavelength ranges.

The designs of mirror autumn-symmetric (non-axisymmetric) antennas are widely known (see, for example, the book by G.Z. Aizenberg and other VHF antennas, in 2 parts, Svyaz Publishing House, Moscow, 1977, part 1, p. .346,) in which the irradiator is outside the field of action of the field reflected from the mirror. In such structures, the influence of the mirror on the input impedance of the irradiator and its coordination with the supply line are almost completely eliminated. A significant advantage of such antennas is that the feed and the antenna feed line with the remote feed does not obscure its opening. Autumn-symmetric antennas may include a mirror antenna system with two fixed irradiators (see the description of the utility model patent RU No. 39429, IPC H01Q 19/13, published April 27, 2004), including a movable reflector mounted above the stationary horn irradiators, and a waveguide switch, which alternately supplies microwave energy to a particular emitter depending on the position of the reflector relative to the focal axis of the paraboloid.

The disadvantage of such an antenna system is the complexity of its design, while this system cannot work simultaneously in two frequency ranges.

A known antenna system (see the description of the invention to copyright certificate No. 104864, application. January 20, 1956), which contains a main mirror, two curved intermediate mirrors made in the form of single-line arrays, the wires of which are mutually perpendicular, and two irradiators with different polarizations. The wires of the grating of one intermediate mirror are parallel to the electric field vector of one irradiator, and the wires of the other intermediate mirror are parallel to the electric field vector of the second irradiator, as a result of which each of the intermediate mirrors does not affect the field of the second irradiator. Both intermediate mirrors are arranged so that their phase centers coincide with the focus of the main mirror. The energy emitted by each of the irradiators is directed to the corresponding intermediate mirror and, after reflection from both mirrors, propagates in the direction of the main mirror, as if based on a common source located at its focus. As a result, radiation patterns are the same when both antennas are excited and have the same direction of maximum radiation. Thanks to this solution, an increase in the isolation between the transmitting and receiving paths in the mirror antenna, including irradiators with different polarizations, has been achieved.

The antenna system according to the invention No. 104864 described above, as described above analogs, also works in only one operating frequency range.

Known bipolarization reflector antenna (see the description of the invention to patent RU No. 2175802, H01Q 19/00, publ. 10.11.2001), is intended for use in broadband communication systems, the design of which ensures the operation of the antenna in the double frequency band at orthogonal polarizations during "isolation" »More than 60 dB. The design of such an antenna contains an asymmetric parabolic reflector, two irradiators and a polarization selector made of parallel cylindrical rods, forming an irradiating device in the aggregate, while a selective selective mirror with an absorbing screen is installed in front of one of the irradiators.

However, this solution also does not solve the problem of ensuring the operation of the antenna simultaneously on two wavelength ranges and in one direction.

As a prototype of the inventive mirrored antenna, a solution of the antenna system has been adopted, which coincides with the claimed solution for the largest number of design features (see the description of the invention to patent US 1484102, IPC H01Q 19/00, publ. 08.24.1977). The antenna system of the aforementioned patent contains orthogonally polarized irradiators, each mounted in front of a corresponding parabolic reflector, the surface of which is formed by many parallel linear elements that provide reflection of electromagnetic waves of the polarization that is characteristic of the irradiator installed in front of this reflector. Reflectors and corresponding irradiators are arranged in pairs, and in a pair of reflectors are installed at a certain distance from each other, so that in one pair the distance between one irradiator and the reflective surface along the focal axis of its reflector is slightly greater than the same distance between the other irradiator and the reflector tuned to it.

The known solution according to the patent US 1484102 provides a double use of the operating frequencies due to the orthogonal polarization of the irradiators and reflectors of the antenna system, which determines the increase in the efficiency of use of the corresponding range. However, the disadvantage of the prototype is the impossibility of simultaneous operation of the antenna in two ranges, in one direction and with the organization of a frequency-spaced mode of operation.

Disclosure of invention

The claimed invention solves the problem of creating a dual-band reflector antenna operating in the same direction and on one alignment device.

The problem is solved due to the fact that in a mirror antenna containing an irradiating device, including two emitters with orthogonal polarizations, and a mirror with two parabolic reflective surfaces formed by parallel linear elements, and the linear elements of one parabolic surface are oriented orthogonally relative to linear elements of another parabolic surface , according to the claimed invention, one emitter is made in the form of an emitter of the lower wavelength range, dr an emitter in the form of an emitter of the upper wavelength range, the aforementioned emitters are mounted on the same supporting structure, the phase center of the upper emitter being located between it and the lower wave emitter, and the phase center of the lower emitter is located between this emitter and installed behind the lower irradiator reflector, while parabolic reflective surfaces are parallel to each other and made with the same focal length, and placed in such an image ohm, that the focus of one parabolic surface is aligned with the phase center of the lower range emitter, and the focus of another parabolic surface is aligned with the phase center of the upper range emitter. In other words, the parabolic reflective surfaces in the inventive mirror antenna are parallel to each other at any point on these surfaces intersected by conditional lines parallel to their common focal axis and spaced apart by a distance equal to the distance between the phase centers of the emitters.

The technical result of the proposed solution is to ensure the operation of the mirror antenna in two frequency ranges at orthogonal polarizations, the maximum “isolation” in the double frequency band is ensured, its noise immunity is improved, while the irradiating antenna system is characterized by a high gain and directivity, which leads to high electrical parameters of the antenna in general, the design of which is characterized by simplicity of manufacture and relatively small dimensions.

In a specific implementation of the inventive mirrored antenna, the emitters of the irradiating device are made in the form of two loop vibrators, the canvases of which are placed in parallel, spaced apart planes, each vibrator formed by two open rhombic-shaped frames whose diagonals coincide with the longitudinal axis of the corresponding vibrator passing through open vertices of the frames to each other in the central part of each vibrator, in which the power points are located, a reflector made in the form a flat screen, located on the side of the loop of the lower range in a plane parallel to the planes of the placement of the mentioned loop vibrators, the vibrator of the upper waveband is mounted on the vibrator of the lower range and placed relative to it orthogonally, so that the longitudinal axis of the vibrators are perpendicular to each other in projection onto the plane of the reflector, when the phase center of the loopback vibrator of the lower range is between its web and the plane of the reflector, and the phase center of the loopback vibrator of the upper the range is between its canvas and the canvas of the loopback vibrator of the lower range.

Both emitters are mounted on one support mechanism, mounted with the possibility of adjusting the position of the irradiating device in space and relative to parabolic reflective surfaces.

The support mechanism, in the particular case, can be made up of two brackets, one end of which is connected directly to the frame of parabolic reflective surfaces, and the other ends of these brackets, remote from the parabolic surface, are connected to the frame by means of suspensions, and racks are installed at these ends fixing the irradiating device.

It is preferable to perform parallel linear elements of parabolic reflective surfaces from bent along an arc of the tubes.

A brief description of the drawings.

The technical solution of the inventive mirror antenna is illustrated by the following drawings:

figure 1 - presents the inventive dual-band reflector antenna, General view;

figure 2 is a view of figure 1;

figure 3 is a view of the irradiating device from the side of parabolic reflective surfaces;

figure 4 - view In figure 3.

The implementation of the invention

The inventive mirror antenna contains two parabolic reflective surfaces 1 and 2, one of which is formed by parallel linear elements 3, and the other by parallel linear elements 4. Linear elements 3 and 4 are made in the form of tubes bent along an arc and mounted on a single frame 5, forming a mirror antennas with two reflective, spaced apart, parabolic surfaces. Moreover, the linear elements 3 forming one parabolic surface, i.e. surface 1 are oriented orthogonally with respect to the linear elements 4 forming another parabolic surface, i.e. surface 2. In the drawings (see FIG. 1 and FIG. 2), surface 1 is formed by horizontally oriented tubes 3, and this parabolic surface reflects a horizontal polarization wave and is transparent to a vertical polarization wave, and surface 2 is formed by vertically oriented tubes, reflects a wave of vertical polarization and transparent to a wave of horizontal polarization. The antenna mirror is mounted on the mast (or other support mechanism) by means of the support unit 6, which provides the possibility of adjusting the movement of the mirror in space.

The irradiating device of the claimed antenna includes two emitters 7 and 8, characterized by orthogonal polarizations, and one emitter 7 is made in the form of a radiator of the lower wavelength range, and the other emitter 8 is in the form of a radiator of the upper wavelength range. The emitters 7 and 8 are mounted on the same supporting structure. In a preferred embodiment of the inventive antenna, the emitters of the irradiating device are made in the form of two loop vibrators, the canvases of which are placed in parallel planes (see FIG. 3, FIG. 4), spaced apart by a distance equal to 0.25 λ _in , where λ _in - the average wavelength of the upper range. Each loop vibrator is formed by two non-closed rhombic-shaped frames whose diagonals coincide with the longitudinal axis of the corresponding vibrator (O ₁ axis or O ₂ axis) passing through the open vertices of the frames facing each other in the central part of each vibrator, in which the power points are located (on drawings not shown).

The irradiating device includes a reflector 9 made in the form of a flat screen located on the side of the loop vibrator 7 of the lower range in a plane parallel to the planes of the mentioned loop vibrators 7 and 8 and at a distance equal to 0.25 λ _n , where λ _n is the average wavelength lower range.

The vibrator 8 of the upper wave range is mounted on the vibrator 7 of the lower range and placed relative to it orthogonally, so that the longitudinal axis O ₁ and O _{2 of the} vibrators 7 and 8 are perpendicular to each other in projection onto the plane of the reflector.

The phase center of the loop vibrator 7, i.e. the emitter of the lower range is located between its canvas and the plane of the reflector 9. The phase center of the loop vibrator 8, i.e. the emitter of the upper range, is located between its blade and the blade of the vibrator 7, i.e. between emitters of the upper and lower ranges.

The middle part of the vibrator 7 is equipped with metal plates 10 that act as a reflector for the upper range emitter, i.e. loop vibrator 8.

Power to the irradiating device is supplied through two supply lines. The cable 11 of the upper range signal connected to the loop vibrator 8 is laid inside the tubular conductor of the vibrator 7, and passed on two adjacent sides of one of its rhombic cells, and on two adjacent sides of the other rhombic cell of the vibrator 7 laid cable 12 of the lower range signal connected with power points of the loop vibrator 7.

Parabolic reflective surfaces 1 and 2 are made with the same focal length, they are characterized by equal sizes and have the same curvature of the parabola. A distinctive feature of the inventive mirror antenna is that the parabolic surfaces 1 and 2 are arranged so that the focus of one parabolic surface, namely the parabolic surface 2 formed by the vertical tubes 4, is aligned with the phase center of the emitter 7 of the lower range, and the focus of the other parabolic surface 1 formed by horizontal tubes 3, combined with the phase center of the emitter 8 of the upper range. Thus, the reflecting parabolic surfaces of the mirror are offset by a distance at which the distance between their foci is equal to the distance between the phase centers of the emitter 7 and the emitter 8.

The irradiating device of the claimed antenna is mounted on a support mechanism, mounted with the ability to adjust the position of the emitters. This mechanism includes two brackets 13, one ends of which are connected to the frame 5 of parabolic reflective surfaces, and the other ends of these brackets 13 are connected to the frame 5 by means of suspensions 14. The irradiating device is mounted on the racks 15.

Claims (5)

1. A mirror antenna comprising an irradiating device comprising two emitters with orthogonal polarizations and a mirror with two parabolic reflective surfaces formed by parallel linear elements, the linear elements of one parabolic surface being oriented orthogonally relative to linear elements of another parabolic surface, characterized in that one emitter made in the form of an emitter of the lower wavelength range, another emitter is in the form of an emitter of the upper range for waves, the said emitters are mounted on the same supporting structure, with the phase center of the upper range emitter located between it and the lower wavelength emitter, and the phase center of the latter located between the lower range emitter and the reflector installed behind it, parabolic reflective surfaces are made with the same focal length and placed in such a way that the focus of one parabolic surface is aligned with the phase center of the emitter of the lower range, and the focus of another parabolic surface aligned with the phase center of the upper range emitter. 2. The antenna according to claim 1, characterized in that the emitters of the irradiating device are made in the form of two loop vibrators, the canvases of which are placed in parallel planes spaced apart from each other, each vibrator being formed by two open rhombic-shaped frames whose diagonals coincide with the longitudinal axis of the corresponding a vibrator passing through open vertices of the frames facing each other in the central part of each vibrator, in which the power points are located, a reflector made in the form of a flat screen, placed on the side of the loop of the lower range in a plane parallel to the planes of placement of the said loop vibrators, the upper wave range vibrator is mounted on the vibrator of the lower range and placed relative to it orthogonally, so that the longitudinal axis of the vibrators are perpendicular to each other in projection onto the plane of the reflector, while the phase center the loop of the lower range vibrator is located between its web and the reflector plane, and the phase center of the loop of the upper range is m between his canvas and the canvas of the loopback vibrator of the lower range. 3. The antenna according to claim 1 or 2, characterized in that the irradiating device is mounted on a support mechanism mounted with the ability to control the position of the emitters. 4. The antenna according to claim 3, characterized in that the support mechanism comprises two brackets, one ends of which are connected to the skeleton of parabolic reflective surfaces, and the other ends are connected to the said skeleton by means of suspensions, and racks for fixing the irradiating device are installed at these ends. 5. The antenna according to claim 1, characterized in that the linear elements of parabolic reflective surfaces, in each of them, are made in the form of tubes parallel and bent along an arc.

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