CN109616775B - Circularly polarized antenna - Google Patents
Circularly polarized antenna Download PDFInfo
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- CN109616775B CN109616775B CN201811344523.2A CN201811344523A CN109616775B CN 109616775 B CN109616775 B CN 109616775B CN 201811344523 A CN201811344523 A CN 201811344523A CN 109616775 B CN109616775 B CN 109616775B
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- metal layer
- metal sheet
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- microstrip line
- circularly polarized
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
- H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
- H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/48—Earthing means; Earth screens; Counterpoises
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/50—Structural association of antennas with earthing switches, lead-in devices or lightning protectors
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- Variable-Direction Aerials And Aerial Arrays (AREA)
- Waveguide Aerials (AREA)
Abstract
The invention relates to a circularly polarized antenna, which comprises a feed column, and a reflection metal layer, a grounding metal layer and a radiation metal layer which are sequentially arranged at intervals; the grounding metal layer comprises a first metal sheet and a second metal sheet; the inner edge of the first metal sheet and the outer edge of the second metal sheet are used for forming a TE11 die and a TE21 die in a matching mode; the radiation metal layer comprises a first radiation band, a second radiation band, a first microstrip line and a second microstrip line, and one end of the first radiation band and one end of the second radiation band are electrically connected and are used for being coupled with the first metal sheet and the second metal sheet to form perturbation; in use, the inner edge of the first metal sheet and the outer edge of the second metal sheet cooperate to form a TE11 mode and a TE21 mode having a large frequency difference. Under the perturbation formed by the coupling of the first radiation band, the second radiation band, the first metal sheet and the second metal sheet, the frequency difference between the TE11 mode and the TE21 mode is reduced, and further the circular polarization bandwidths of the TE11 mode and the TE21 mode are widened.
Description
Technical Field
The invention relates to the technical field of antennas, in particular to a circularly polarized antenna.
Background
Circularly polarized microstrip patch antennas are very popular in many applications. Such as satellite communication systems, Global Positioning Systems (GPS) and Radio Frequency Identification (RFID). They have several advantages, including low profile, light weight, and low cost. However, the performance of circularly polarized microstrip patch antennas is limited by bandwidth. Currently, with the rapid development of communication, wireless communication with high data rate is urgently needed, and the circularly polarized microstrip patch antenna with the wide-axis ratio bandwidth is increasingly required.
The existing circularly polarized microstrip patch antenna is realized by a single-point feed or a multi-point feed, and the single-point feed has the advantages of simple structure and low cost, but the circular polarization axis ratio bandwidth is narrow; the advantages of multipoint feeding are that the standing wave ratio bandwidth and the circular polarization bandwidth can be improved, and the cross polarization can be inhibited, but the feeding network is complex and the cost is high.
Disclosure of Invention
Based on this, the present invention provides a circularly polarized antenna to solve the problem of complex feeding network, which overcomes the defects of the prior art.
A circularly polarized antenna comprises a feed column, and a reflection metal layer, a grounding metal layer and a radiation metal layer which are sequentially arranged at intervals; the grounding metal layer comprises a first metal sheet and a second metal sheet; the outer contour of the first metal sheet is circular, a material removing area is formed in the first metal sheet and comprises three elliptical areas, the centers of the three elliptical areas are overlapped, and the long axes of two adjacent elliptical areas form an included angle of 45 degrees; the outer contour of the second metal sheet is circular, the second metal sheet is arranged in the center of the material removing area, the outer edge of the second metal sheet and the inner edge of the material removing area are arranged at intervals, and the inner edge of the first metal sheet and the outer edge of the second metal sheet are used for forming a TE11 die and a TE21 die in a matching mode; the radiation metal layer comprises a first radiation band, a second radiation band, a first microstrip line and a second microstrip line, one end of the first radiation band is electrically connected with one end of the second radiation band and is used for being coupled with a first metal sheet and a second metal sheet to form perturbation, one end of the first microstrip line is electrically connected with the other end of the first radiation band, the other end of the first microstrip line is electrically connected with one end of the feed column, the other end of the feed column is electrically connected with the first metal sheet, one end of the second microstrip line is electrically connected with the second radiation band, and the other end of the second microstrip line is used for signal transmission.
In the circularly polarized antenna, in use, the inner edge of the first metal sheet and the outer edge of the second metal sheet cooperate to form a TE11 mode and a TE21 mode with large frequency difference. Under the perturbation formed by the coupling of the first radiation band, the second radiation band, the first metal sheet and the second metal sheet, the frequency difference between the TE11 mode and the TE21 mode is reduced, and further the circular polarization bandwidths of the TE11 mode and the TE21 mode are widened.
The narrow-bandwidth circularly polarized antenna is matched with the perturbation to expand the bandwidth to form the wide-bandwidth circularly polarized antenna.
In one embodiment, the first radiation band and the second radiation band are both linear, and the first radiation band and the second radiation band are arranged vertically in an L shape; the structure is simple, and the circular polarization bandwidth can be effectively widened.
In one embodiment, the bandwidths of the first and second radiating strips are both 18mm, and the bandwidths of the first and second microstrip lines are both 0.4 mm. The length of the first microstrip line and the second microstrip line is adjusted to adjust the cut-off frequency of the low frequency of the antenna, the width adjustment of the first radiation band, the second radiation band, the first microstrip line and the second microstrip line can adjust the standing wave bandwidth and the axial ratio bandwidth of the antenna, and when the bandwidths of the first radiation band and the second radiation band are both 18mm and the bandwidths of the first microstrip line and the second microstrip line are both 0.4mm, the circularly polarized antenna has better standing wave bandwidth and axial ratio bandwidth.
In one embodiment, the major axes of the three elliptical areas are equal, and the minor axes of the three elliptical areas are equal; therefore, the circular polarization axial ratio bandwidth and the standing wave bandwidth of the circular polarization antenna are obviously improved.
In one embodiment, the first microstrip line and the second microstrip line are both serpentine. The snakelike first microstrip line and the snakelike second microstrip line can reduce the structure size of antenna, and the circular polarized antenna of being convenient for realizes the miniaturization.
In one embodiment, the circularly polarized antenna further includes a first dielectric plate disposed on a side of the radiation metal layer away from the ground metal layer. The arrangement of the first dielectric plate can reduce the low-end frequency of the antenna and improve the gain of the antenna.
In one embodiment, the circularly polarized antenna further includes a second dielectric plate, the second dielectric plate is disposed between the radiation metal layer and the ground metal layer, the radiation metal layer is disposed on a side of the second dielectric plate away from the reflection metal layer, and the ground metal layer is disposed on a side of the second dielectric plate close to the reflection metal layer. The arrangement of the second dielectric plate facilitates the realization of the arrangement of the radiation metal layer and the grounding metal layer at intervals.
In one embodiment, the reflective metal layer is a circular third metal sheet. Simple structure, and can correspond with circular first sheetmetal, save material.
In one embodiment, the circularly polarized antenna further comprises a plastic pillar disposed between the ground metal layer and the reflective metal layer, one end of the plastic pillar is connected to the ground metal layer, and the other end of the plastic pillar is connected to the reflective metal layer. The plastic posts can be arranged to facilitate the grounding metal layer and the reflecting metal layer to maintain the spaced state.
Drawings
Fig. 1 is a schematic structural diagram of a circular polarization antenna according to an embodiment;
FIG. 2 is a schematic structural diagram of a radiation metal layer according to an embodiment;
fig. 3 is a schematic structural diagram of a ground metal layer according to an embodiment;
FIG. 4 is a graph illustrating the standing wave bandwidth of a circularly polarized antenna according to one embodiment;
fig. 5 is an axial ratio bandwidth diagram of the circular polarized antenna according to an embodiment.
Description of reference numerals:
110. the antenna comprises a radiation metal layer 111, a first radiation strip 112, a second radiation strip 113, a first microstrip line 114, a second microstrip line 120, a ground metal layer 121, a first metal sheet 121a, a material removing area 122, a second metal sheet 130, a reflection metal layer 210, a first dielectric plate 220, a second dielectric plate 300, a feed column 400, a dielectric layer 500 and a plastic column.
Detailed Description
To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.
Referring to fig. 1, an embodiment provides a circular polarization antenna, which includes a feeding post 300, and a reflective metal layer 130, a ground metal layer 120, and a radiation metal layer 110, which are sequentially disposed at intervals. As shown in fig. 3, the ground metal layer 120 includes a first metal sheet 121 and a second metal sheet 122; the outer contour of the first metal sheet 121 is circular, a material removing area 121a is formed inside the first metal sheet 121, the material removing area 121a comprises three elliptical areas, the centers of the three elliptical areas are overlapped, and the long axes of two adjacent elliptical areas form an included angle of 45 degrees; the outer contour of the second metal sheet 122 is circular, the second metal sheet 122 is disposed at the center of the material removing region 121a, the outer edge of the second metal sheet 122 is spaced from the inner edge of the material removing region 121a, and the inner edge of the first metal sheet 121 and the outer edge of the second metal sheet 122 are used for forming a TE11 mold and a TE21 mold in a matching manner; referring to fig. 2, the radiation metal layer 110 includes a first radiation strip 111, a second radiation strip 112, a first microstrip line 113 and a second microstrip line 114, one end of the first radiation strip 111 and one end of the second radiation strip 112 are electrically connected to couple with the first metal plate 121 and the second metal plate 122 to form a perturbation, one end of the first microstrip line 113 is electrically connected to the other end of the first radiation strip 111, the other end of the first microstrip line 113 is electrically connected to one end of the feed column 300, the other end of the feed column 300 is electrically connected to the first metal plate 121, one end of the second microstrip line 114 is electrically connected to the second radiation strip 112, and the other end of the second microstrip line 114 is used for signal transmission.
In the circular polarization antenna, in use, the inner edge of the first metal sheet 121 and the outer edge of the second metal sheet 122 cooperate to form a TE11 mode and a TE21 mode having a large frequency difference. Under the perturbation formed by the coupling of the first radiating strip 111, the second radiating strip 112, the first metal sheet 121 and the second metal sheet 122, the frequency difference between the TE11 mode and the TE21 mode is reduced, and the circular polarization bandwidths of the TE11 mode and the TE21 mode are widened.
In one embodiment, the first radiation band 111 and the second radiation band 112 are both linear, and the first radiation band 111 and the second radiation band 112 are disposed perpendicularly in an L-shape. The structure is simple, and the circular polarization bandwidth can be effectively widened.
In one embodiment, the bandwidths of the first radiation strip 111 and the second radiation strip 112 are both 18mm, and the bandwidths of the first microstrip line 113 and the second microstrip line 114 are both 0.4 mm. The length of the first microstrip line 113 and the second microstrip line 114 can be adjusted to adjust the cut-off frequency of the low frequency of the antenna, the width adjustment of the first radiation band 111, the second radiation band 112, the first microstrip line 113 and the second microstrip line 114 can adjust the standing wave bandwidth and the axial ratio bandwidth of the antenna, and when the bandwidths of the first radiation band 111 and the second radiation band 112 are both 18mm and the bandwidths of the first microstrip line 113 and the second microstrip line 114 are both 0.4mm, the circularly polarized antenna has better standing wave bandwidth and axial ratio bandwidth.
In one embodiment, the major axes of the three elliptical areas are equal, and the minor axes of the three elliptical areas are equal; therefore, the circular polarization axial ratio bandwidth and the standing wave bandwidth of the circular polarization antenna are obviously improved.
In one embodiment, the first microstrip line 113 and the second microstrip line 114 are both serpentine. The serpentine first microstrip line 113 and the serpentine second microstrip line 114 can reduce the structural size of the antenna, which is convenient for realizing miniaturization of the circularly polarized antenna.
In an embodiment, the circular polarization antenna further includes a first dielectric plate 210, and the first dielectric plate 210 is disposed on a side of the radiation metal layer 110 away from the ground metal layer 120. The first dielectric plate 210 is disposed to reduce the low-end frequency of the antenna and increase the gain of the antenna.
Referring to fig. 1, in an embodiment, the circular polarization antenna further includes a second dielectric plate 220, the second dielectric plate 220 is disposed between the radiation metal layer 110 and the ground metal layer 120, the radiation metal layer 110 is disposed on one side of the second dielectric plate 220, which is far away from the reflection metal layer 130, and the ground metal layer 120 is disposed on one side of the second dielectric plate 220, which is close to the reflection metal layer 130. The second dielectric plate 220 is disposed to facilitate the radiation metal layer 110 and the ground metal layer 120 to be spaced apart from each other.
It should be noted that the ground metal layer 120 is formed on the second dielectric plate 220 by etching or electroplating, and the power feed metal layer 110 is formed on the first dielectric plate 210 or the second dielectric plate 220 by etching or electroplating. Specifically, in the present embodiment, the ground metal layer 120 and the radiation metal layer 110 are both formed on the second dielectric plate 220 by etching.
In one embodiment, the reflective metal layer 130 is a circular third metal sheet. The structure is simple, and the first metal sheet can correspond to the circular first metal sheet 121, so that the material is saved.
In one embodiment, the circularly polarized antenna further includes a plastic pillar 500 disposed between the ground metal layer 120 and the reflective metal layer 130, one end of the plastic pillar 500 is connected to the ground metal layer 120, and the other end of the plastic pillar 500 is connected to the reflective metal layer 130. The plastic posts 500 can be disposed to facilitate the ground metal layer 120 and the reflective metal layer 130 to maintain a spaced state.
Specifically, a dielectric layer 400 is disposed between the reflective metal layer 130 and the ground metal layer 120. Further, the dielectric layer 400 is an air layer. Preferably, the distance between the ground metal layer 120 and the reflective metal layer 130 is 35 mm.
Referring to fig. 4, the circular polarization antenna of the present embodiment has a standing wave bandwidth of 1.24 to 1.82GHz, which is 40.6%.
With reference to fig. 5, the circular polarization axial ratio bandwidth of the circular polarization antenna of the present embodiment is 1.25 to 1.57GHz, which reaches 22.7%.
The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.
Claims (9)
1. A circularly polarized antenna is characterized by comprising a feed column, and a reflection metal layer, a grounding metal layer and a radiation metal layer which are sequentially arranged at intervals;
the grounding metal layer comprises a first metal sheet and a second metal sheet; the outer contour of the first metal sheet is circular, a material removing area is formed in the first metal sheet and comprises three elliptical areas, the centers of the three elliptical areas are overlapped, and the long axes of two adjacent elliptical areas form an included angle of 45 degrees; the outer contour of the second metal sheet is circular, the second metal sheet is arranged in the center of the material removing area, the outer edge of the second metal sheet and the inner edge of the material removing area are arranged at intervals, and the inner edge of the first metal sheet and the outer edge of the second metal sheet are used for forming a TE11 die and a TE21 die in a matching mode;
the radiation metal layer comprises a first radiation band, a second radiation band, a first microstrip line and a second microstrip line, one end of the first radiation band is electrically connected with one end of the second radiation band and is used for being coupled with a first metal sheet and a second metal sheet to form perturbation, one end of the first microstrip line is electrically connected with the other end of the first radiation band, the other end of the first microstrip line is electrically connected with one end of the feed column, the other end of the feed column is electrically connected with the first metal sheet, one end of the second microstrip line is electrically connected with the second radiation band, and the other end of the second microstrip line is used for signal transmission.
2. The circularly polarized antenna of claim 1, wherein the first radiating strip and the second radiating strip are both linear, and the first radiating strip is disposed perpendicular to the second radiating strip in an L-shape.
3. The circular polarization antenna of claim 1, wherein the first and second radiation bands each have a bandwidth of 18mm, and the first and second microstrip lines each have a bandwidth of 0.4 mm.
4. The circularly polarized antenna of claim 1, wherein the major axes of the three elliptical areas are equal and the minor axes of the three elliptical areas are equal.
5. The circular polarization antenna of claim 1, wherein the first microstrip line and the second microstrip line are serpentine.
6. The circular polarization antenna of claim 1, further comprising a first dielectric plate disposed on the radiation metal layer on a side away from the ground metal layer.
7. The circularly polarized antenna of claim 1, further comprising a second dielectric plate disposed between the radiation metal layer and the ground metal layer, wherein the radiation metal layer is disposed on the second dielectric plate at a side away from the reflective metal layer, and the ground metal layer is disposed on the second dielectric plate at a side close to the reflective metal layer.
8. The circularly polarized antenna of claim 1, wherein the reflective metal layer is a circular third metal sheet.
9. The circularly polarized antenna of claim 1, further comprising a plastic post disposed between the ground metal layer and the reflective metal layer, wherein one end of the plastic post is connected to the ground metal layer and the other end of the plastic post is connected to the reflective metal layer.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811344523.2A CN109616775B (en) | 2018-11-12 | 2018-11-12 | Circularly polarized antenna |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201811344523.2A CN109616775B (en) | 2018-11-12 | 2018-11-12 | Circularly polarized antenna |
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| CN109616775A CN109616775A (en) | 2019-04-12 |
| CN109616775B true CN109616775B (en) | 2020-09-18 |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103280627A (en) * | 2013-05-23 | 2013-09-04 | 西安电子科技大学 | CPW (Co-Planar Waveguide) feeding broadband circular polarization antenna |
| CN105161848A (en) * | 2015-09-29 | 2015-12-16 | 中国电子科技集团公司第五十四研究所 | Elliptical slot circularly-polarized microstrip antenna |
| CN206271883U (en) * | 2016-12-13 | 2017-06-20 | 广东工业大学 | A kind of circularly-polarized patch antenna for medical treatment detection |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100358977B1 (en) * | 2001-02-20 | 2002-11-01 | 엔알디테크 주식회사 | Circular Polarization NRD Guide |
| CN105305045B (en) * | 2015-10-15 | 2017-11-07 | 厦门大学 | T-shaped/oblique L-type drainage gap double-frequency broadband double-circle polarization micro-strip laminated antenna |
| CN105226390B (en) * | 2015-10-16 | 2017-11-17 | 大连海事大学 | A kind of 840/920MHz double frequency round polarized radio frequency identification reader antenna and its impedance matching methods |
| CN105789908B (en) * | 2016-04-19 | 2019-05-24 | 电子科技大学 | A kind of novel circular polarisation or double-circle polarization cylinder Luneberg lens antenna |
| CN206098687U (en) * | 2016-09-30 | 2017-04-12 | 深圳市维力谷无线技术股份有限公司 | Support navigation antenna of low section high -gain of multisystem |
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2018
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Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103280627A (en) * | 2013-05-23 | 2013-09-04 | 西安电子科技大学 | CPW (Co-Planar Waveguide) feeding broadband circular polarization antenna |
| CN105161848A (en) * | 2015-09-29 | 2015-12-16 | 中国电子科技集团公司第五十四研究所 | Elliptical slot circularly-polarized microstrip antenna |
| CN206271883U (en) * | 2016-12-13 | 2017-06-20 | 广东工业大学 | A kind of circularly-polarized patch antenna for medical treatment detection |
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