CN114204277B - Broadband coaxial metal and medium composite ridge waveguide polarizer - Google Patents
Broadband coaxial metal and medium composite ridge waveguide polarizer Download PDFInfo
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- CN114204277B CN114204277B CN202111439059.7A CN202111439059A CN114204277B CN 114204277 B CN114204277 B CN 114204277B CN 202111439059 A CN202111439059 A CN 202111439059A CN 114204277 B CN114204277 B CN 114204277B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/24—Polarising devices; Polarisation filters
- H01Q15/242—Polarisation converters
- H01Q15/244—Polarisation converters converting a linear polarised wave into a circular polarised wave
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/12—Supports; Mounting means
- H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
- H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
- H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
- H01Q1/246—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for base stations
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/14—Reflecting surfaces; Equivalent structures
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
- H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
- H01Q3/30—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array
- H01Q3/34—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array by electrical means
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q5/00—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements
- H01Q5/50—Feeding or matching arrangements for broad-band or multi-band operation
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- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Waveguide Aerials (AREA)
Abstract
The invention discloses a broadband coaxial metal and medium composite ridge waveguide polarizer, and belongs to the technical field of microwave antennas. The waveguide comprises a coaxial circular waveguide and two metal and medium composite ridges arranged in the coaxial circular waveguide; the two ridges are connected with the coaxial circular waveguide outer conductor and are symmetrical relative to the axis of the coaxial circular waveguide; the two ridges are both formed by compounding metal ridges and a medium covering the top ends of the metal ridges; transition sections are arranged at the two ends of the metal ridge and the medium sheet. The invention has the characteristics of obvious bandwidth broadening, simple structure, no debugging, high reliability and suitability for batch production.
Description
Technical Field
The invention relates to the technical field of microwave antennas, in particular to a broadband coaxial metal and dielectric composite ridge waveguide polarizer.
Background
In satellite communication services, a high-efficiency and high-gain transceiving antenna is an important guarantee for normal operation, and a reflector antenna is the most widely applied antenna form in satellite communication, and is particularly suitable for forming high-gain needle-shaped or special-shaped beams in a microwave band. The development of dual-frequency sharing and multi-frequency sharing satellite communication earth station antenna is an important development direction of the existing satellite communication earth station antenna, the multi-frequency band sharing is used for expanding communication capacity and realizing one station with multiple purposes, namely, a pair of antenna feed system can work in two or more satellite communication wave bands simultaneously, so the station building cost of the earth station is greatly reduced, the multi-frequency band sharing terminal antenna is a hotspot of the existing research, the key point is the research of the multi-frequency band sharing feed source, and the demand of the high-performance miniaturized feed source with simple structure, small volume and low cost is increased day by day.
With the rapid development of the communication industry, small-bore antennas are increasingly used. The transmission and radiation of two kinds of microwave signals of high frequency and low frequency in the coaxial feed source system are accomplished through relatively independent channels, the high frequency signal propagates in the internal circular waveguide, the low frequency signal propagates in the peripheral coaxial waveguide, the separation between the two frequency bands is better, and the complicated multi-frequency wave splitting structure can be avoided, the design of a rear end network is greatly simplified, and the feed source network has a relatively compact structure, so that the feed source system is very suitable for small-caliber antennas and feed-forward antenna systems. When the traditional coaxial feed source network realizes circular polarization, the circular polarization is mostly realized in a circular waveguide or a square waveguide section after frequency separation, and the commonly used waveguide circular polarizer types include a screw regulation type, a medium insert type, a corrugated type, a partition plate type, a ridge waveguide type and the like. However, the adoption of the scheme can increase the overall size of the feed source network system and is not beneficial to miniaturization design.
The existing coaxial waveguide circular polarizer is realized by inserting a metal pin or a metal diaphragm into a coaxial waveguide cavity, the circular polarization meeting the requirement is obtained by adjusting the depth of the inserted pin and the diaphragm, and the working bandwidth is about 10%. The coaxial waveguide circular polarizer of the type has the problems of narrow bandwidth, incapability of meeting dual-band application, complex debugging and large difference between test and theoretical calculation.
Disclosure of Invention
In view of the above, the present invention provides a broadband coaxial metal and dielectric composite ridge waveguide polarizer. The invention can meet the application in the field of broadband and multiband satellite communication reflector antennas, has obvious bandwidth broadening, is free from debugging, has simple structure, and is particularly suitable for broadband and dual-frequency coaxial feed source network systems.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows:
a broadband coaxial metal and dielectric composite ridge waveguide polarizer comprises a coaxial waveguide outer waveguide and a coaxial waveguide inner waveguide; the coaxial waveguide inner waveguide is positioned in the coaxial waveguide outer waveguide, and the axes of the coaxial waveguide inner waveguide and the coaxial waveguide outer waveguide are overlapped to form a coaxial waveguide; two opposite ridges are arranged on the outer waveguide of the coaxial waveguide; the ridge comprises a metal ridge and a medium ridge, wherein a metal ridge hole is formed in the wall surface of the metal ridge, which is opposite to the coaxial inner waveguide, and a medium spine matched with the metal ridge hole is formed in the medium ridge surface attached to the metal ridge; the distances from the two ends of the ridge to the middle of the ridge and the axis of the coaxial waveguide are sequentially reduced.
Further, the metal ridge and the dielectric ridge are in a step structure or a curve structure.
Furthermore, the height difference between the adjacent step surfaces of the metal ridge and the medium ridge of the step structure is reduced from the two ends of the ridge to the middle of the ridge in sequence.
Further, the dielectric constant of the dielectric ridge is any value between 1 and 10.
Furthermore, a first flange plate used for connecting the feed source horn and a second flange plate used for connecting the feed source network are respectively arranged at two ports of the coaxial waveguide outer waveguide.
Further, the medium ridge and the metal ridge are fixed by metal screws.
Furthermore, the metal ridge hole is a round hole or a square hole.
The invention adopts the technical scheme to produce the beneficial effects that:
1. the realization of the circular polarization function of the invention is mainly completed by adjusting the diameters of the coaxial waveguide outer conductor and the coaxial waveguide inner conductor, the sizes of the first ridge and the second ridge and the dielectric constant of the medium.
2. Compared with the prior art, the structure has the characteristics that the ridge phase shift structure compounded by metal and medium is adopted, the bandwidth is obviously widened, the relative bandwidth is increased from 10% to 60%, the structure is simple, debugging is avoided, the reliability is high, and the structure is suitable for batch production.
3. The invention changes the diameters of the coaxial waveguide outer conductor and the coaxial waveguide inner conductor, the sizes of a pair of symmetrical ridges arranged on the inner wall of the coaxial waveguide outer conductor and the dielectric constant of a medium, so that the propagation constants of two orthogonal main modes in the coaxial circular waveguide are different, when two polarized waves with equal amplitude and same phase enter the coaxial waveguide provided with the ridges, the amplitudes of the two polarized waves are equal and the phase difference is 90 degrees by adjusting the lengths of metal and medium parts of the ridges, the distance from the axes of the coaxial circular waveguide, the thickness of the ridges and the dielectric constant of the medium, so as to form circular polarization. The method is particularly suitable for a coaxial feed network system, and is easy to realize the design of a miniaturized broadband and double-frequency feed network.
Drawings
Fig. 1 is a schematic structural view of the present invention.
Fig. 2 is a side view of the present invention.
Fig. 3 is a cross-sectional view of the present invention.
Fig. 4 is a schematic view of the metal ridge structure of the present invention.
FIG. 5 is a schematic view of a media ridge configuration of the present invention.
FIG. 6 shows the reflection coefficient of polarization 1 in the example of the present invention.
FIG. 7 shows the reflection coefficient of the polarization 2 in the embodiment of the present invention.
Fig. 8 shows the phase difference between polarization 1 and polarization 2 in the example of the present invention.
Description of reference numerals: the coaxial waveguide comprises a coaxial waveguide outer conductor-1, a coaxial waveguide inner conductor-2, a first ridge 3-1, a second ridge 3-2, a connecting flange-4-1, a connecting flange-4-2, a metal ridge-5-1, a metal ridge-5-2, a medium ridge-6-1, a medium ridge-6-2, a metal ridge transition section-7-1, a metal ridge transition section-7-2, a metal ridge hole-8, a medium ridge-10, a medium ridge transition section-9-1 and a medium ridge transition section-9-2.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and specific embodiments.
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.
A broadband coaxial metal and dielectric composite ridge waveguide polarizer comprises a coaxial waveguide outer conductor, a coaxial waveguide inner conductor, a first ridge, a second ridge and a connecting flange; the axes of the coaxial waveguide outer conductor and the coaxial waveguide inner conductor are superposed; the first ridge and the second ridge are arranged in the coaxial waveguide cavity and are connected with the outer conductor of the coaxial waveguide; the first ridge and the second ridge are symmetrical about the axis of the coaxial waveguide; the first ridge and the second ridge are both formed by compounding a metal ridge and a medium covering the top end of the metal ridge, and transition sections are arranged at two ends of the metal ridge and the medium sheet to realize the matching of the waveguide section of the coaxial ridge and the coaxial waveguide.
By changing the diameters of the coaxial waveguide outer conductor and the coaxial waveguide inner conductor, the sizes of the first ridge and the second ridge and the dielectric constant of the medium, the propagation constants of two orthogonal main modes in the coaxial waveguide are different, after two polarized waves with equal amplitude and same phase enter the circular polarizer, the amplitudes of the two polarized waves are equal, and the phase difference is 90 degrees, so that circular polarization is formed.
Furthermore, the diameter ratio of the coaxial waveguide outer conductor to the coaxial waveguide inner conductor is required to meet the electromagnetic wave cut-off in the working frequency band.
Furthermore, the first ridge and the second ridge are in good contact with the coaxial waveguide outer conductor.
Furthermore, the metal ridge parts of the first ridge and the second ridge are in good contact with the medium ridge part.
Further, the dielectric constant of the first dielectric ridge and the second dielectric ridge can be designed to be any value larger than 1 and smaller than 10.
Furthermore, the first ridge, the second ridge and the inner wall of the coaxial waveguide outer conductor are changed by transition.
Furthermore, the transition between the first ridge and the second ridge and the inner wall of the coaxial waveguide outer conductor can be gradual transition or step transition.
Furthermore, the coaxial waveguide can enable the working frequency to be well transmitted.
The following is a more specific example:
referring to fig. 1 to 5, a broadband coaxial metal and dielectric composite ridge waveguide polarizer is provided, which includes a coaxial waveguide outer conductor 1, a coaxial waveguide inner conductor 2, a first ridge 3-1, a second ridge 3-2, a connecting flange 4-1, a connecting flange 4-2, a metal ridge 5-1, a metal ridge 5-2, a dielectric ridge 6-1, a dielectric ridge 6-2, a metal ridge transition section 7-1, a metal ridge transition section 7-2, a metal ridge hole 8, a dielectric ridge transition section 9-1, a dielectric ridge transition section 9-2, and a dielectric spine 10.
The diameter of the coaxial waveguide inner conductor and the diameter of the coaxial waveguide outer conductor are selected to enable the working frequency to be well transmitted, and the principle that the working frequency is more than 1.1 times of the cutoff frequency is taken as the principle.
The coaxial waveguide outer conductor and the coaxial waveguide inner conductor have the same axis.
The first ridge and the second ridge are arranged on the inner wall of the coaxial waveguide outer conductor, are symmetrical about the axis of the coaxial waveguide and are in good contact with the inner wall of the coaxial waveguide outer conductor.
The first and second flat ridges are composed of metal ridges and medium ridges.
The first ridge and the second ridge have the same size.
The two ends of the metal ridge of the first ridge and the second ridge are provided with metal ridge transition sections.
The two ends of the medium ridge of the first ridge and the second ridge are provided with medium ridge transition sections.
The metal ridges of the first ridge and the second ridge are provided with metal ridge holes, and the number of the metal ridges is determined according to the electrical property and the installation requirement.
The medium ridges of the first ridge and the second ridge are provided with medium spines, the number of the medium spines is consistent with the number of the metal ridge holes on the metal ridges, and the medium spines are in good matching contact connection with the metal ridge holes of the metal ridges.
The dielectric constant of the dielectric ridge can be designed to be any value larger than 1 and smaller than 10.
The distance between the first ridge and the second ridge and the inner conductor of the coaxial waveguide is generally larger than 3/4 of the difference between the radius of the outer conductor of the coaxial waveguide and the radius of the inner conductor of the coaxial waveguide, so that the polarizer has good matching performance.
The metal ridge transition section and the medium ridge transition section can be a gradient line or a step transition so as to realize good impedance matching as a design target.
And finally determining the size of the polarizer, and optimizing according to design indexes.
The flange plate is used for being connected with other components.
The electrical transmission performance of the cable is verified, and the method specifically comprises the following steps:
fig. 6 shows the reflection coefficient for polarization 1 in the operating band, and it can be seen that the vertical polarization reflection loss is < -40dB in the designed bandwidth.
Fig. 7 shows the reflection coefficient for polarization 2 in the operating band, and it can be seen that the vertical polarization reflection loss < -25dB in the designed bandwidth.
Fig. 8 shows the phase difference of two orthogonally polarized waves in a frequency band, and it can be seen that the phase difference satisfies 90 ° ± 5 ° in a designed bandwidth.
The broadband coaxial metal and medium composite ridge waveguide polarizer device comprises a coaxial circular waveguide and two metal and medium composite ridges arranged in the coaxial circular waveguide, wherein the two ridges are connected with an outer conductor of the coaxial circular waveguide and are symmetrical relative to the axis of the coaxial circular waveguide; transition sections are arranged at two ends of the metal ridge and the dielectric sheet, and connecting flanges are arranged at two ends of the polarizer and are respectively in mechanical connection with the feed source loudspeaker and the feed coaxial orthomode coupler. Compared with the prior art, the invention adopts a ridge phase-shifting structure compounded by metal and medium in the coaxial circular waveguide, has the advantages of obvious bandwidth broadening, the bandwidth reaching 60 percent, simple structure, excellent performance, no debugging and high reliability, is suitable for batch production, and is particularly suitable for application in a miniaturized coaxial feed network system.
The invention has the following brief working principle:
the circularly polarized wave is decomposed into two linearly polarized waves with equal amplitude and 90-degree phase difference. The working principle of the invention is as follows: after two polarized waves with equal amplitude and same phase enter the coaxial waveguide provided with the ridge, the amplitude of the two polarized waves is equal and the phase difference is 90 degrees by adjusting the length of the metal and medium parts of the ridge, the distance from the axis of the coaxial circular waveguide, the thickness of the ridge and the dielectric constant of the medium, so that circular polarization is formed.
Claims (6)
1. A broadband coaxial metal and dielectric composite ridge waveguide polarizer comprises a coaxial waveguide outer waveguide and a coaxial waveguide inner waveguide; the coaxial waveguide inner waveguide is positioned in the coaxial waveguide outer waveguide, and the axes of the coaxial waveguide inner waveguide and the coaxial waveguide outer waveguide are overlapped to form a coaxial waveguide; the coaxial waveguide external waveguide is characterized in that two opposite ridge structures are arranged on the coaxial waveguide external waveguide; the ridge structure comprises a metal ridge and a medium ridge, wherein a metal ridge hole is formed in the metal ridge surface facing the coaxial inner waveguide, and a medium ridge matched with the metal ridge hole is formed in the medium ridge surface attached to the metal ridge; the distances from the two ends of the ridge structure to the middle of the ridge structure and the axis of the coaxial waveguide are sequentially reduced; the metal ridge and the medium ridge are of a step structure or a curve structure.
2. The broadband coaxial metal-dielectric composite ridge waveguide polarizer of claim 1, wherein the difference in height between adjacent step surfaces of the metal ridge and the dielectric ridge of the step structure decreases from the two ends of the ridge to the middle of the ridge.
3. The broadband coaxial metal and dielectric composite ridge waveguide polarizer of claim 1, wherein the dielectric constant of the dielectric ridge is any value between 1 and 10.
4. The broadband coaxial metal and dielectric composite ridge waveguide polarizer of claim 1, wherein a first flange plate for connecting a feed source horn and a second flange plate for connecting a feed source network are respectively arranged at two ports of the coaxial waveguide outer waveguide.
5. The broadband coaxial metal-dielectric composite ridge waveguide polarizer of claim 1, wherein the dielectric ridge and the metal ridge are fixed by a metal screw.
6. The broadband coaxial metal and dielectric composite ridge waveguide polarizer of claim 1, wherein the metal ridge hole is a circular hole or a square hole.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111439059.7A CN114204277B (en) | 2021-11-30 | 2021-11-30 | Broadband coaxial metal and medium composite ridge waveguide polarizer |
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| CN202111439059.7A CN114204277B (en) | 2021-11-30 | 2021-11-30 | Broadband coaxial metal and medium composite ridge waveguide polarizer |
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| CN114204277A CN114204277A (en) | 2022-03-18 |
| CN114204277B true CN114204277B (en) | 2022-09-02 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| US7663452B2 (en) * | 2005-02-18 | 2010-02-16 | The United States Of America As Represented By The Secertary Of The Navy | Ridge-waveguide filter and filter bank |
| CN104466415B (en) * | 2014-12-08 | 2018-07-27 | 西安电子科技大学 | The high-gain ultra wide band ripple double-ridged horn antenna of lens load |
| CN105304995A (en) * | 2015-10-10 | 2016-02-03 | 成都赛纳赛德科技有限公司 | Ultrawide-band coaxial ridge waveguide adapter |
| US9742069B1 (en) * | 2016-10-17 | 2017-08-22 | Optisys, LLC | Integrated single-piece antenna feed |
| CN108808262A (en) * | 2018-07-06 | 2018-11-13 | 中国电子科技集团公司第五十四研究所 | A kind of four ridge waveguide circular polarizer of broadband |
| CN112886279B (en) * | 2021-01-18 | 2022-12-27 | 中国船舶重工集团公司第七二四研究所 | Method for realizing high-gain omnidirectional biconical antenna array |
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