CN110808458A - Dual-polarization multilayer patch filtering antenna and communication equipment - Google Patents
Dual-polarization multilayer patch filtering antenna and communication equipment Download PDFInfo
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- CN110808458A CN110808458A CN201911180485.6A CN201911180485A CN110808458A CN 110808458 A CN110808458 A CN 110808458A CN 201911180485 A CN201911180485 A CN 201911180485A CN 110808458 A CN110808458 A CN 110808458A
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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
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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
- H01Q1/50—Structural association of antennas with earthing switches, lead-in devices or lightning protectors
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Abstract
The invention discloses a dual-polarization multilayer patch filter antenna and communication equipment, which comprise four layers of dielectric substrates, a metal reflecting plate and a feed probe, wherein the four layers of dielectric substrates sequentially comprise a first layer of dielectric substrate, a second layer of dielectric substrate, a third layer of dielectric substrate and a fourth layer of dielectric substrate from top to bottom; the filtering antenna does not comprise a filtering circuit, and the filtering characteristics are generated in a parasitic mode, so that the filtering antenna has high roll-off characteristics and low pass-band loss.
Description
Technical Field
The invention relates to the field of wireless communication, in particular to a dual-polarized multilayer patch filter antenna and communication equipment.
Background
With the development of wireless communication technology, the requirements for communication systems tend to be small and highly integrated, and the requirements for antenna units are higher and higher. In the 5G technology, the loss of the wireless base station is greatly increased compared with the loss of the previous generation communication system, the loss of energy must be reduced from various layers in order to reduce the energy consumption, and for the dual-polarized antenna unit, polarization isolation and high roll-off property must be made.
In recent years, the design of the filter antenna can be simply classified into the following three types, the first type of design is to cooperatively design a filter and an antenna feed part or simply cascade the filter and a traditional antenna through an impedance converter, the second type of design is to open a slot and dig a hole on a patch antenna or add a metal probe for combination so that a radiator has the filter characteristic, and the third type of design is to enable the radiation of the antenna to generate the filter effect by adding a non-radiation parasitic structure, so that the filter antenna can greatly reduce the transmission loss, reduce the energy loss in a passband, meet the requirement of 5G wireless communication, and is beneficial to the realization of miniaturization and integration.
Disclosure of Invention
In order to overcome the defects and shortcomings of the prior art, the invention provides a dual-polarized multilayer patch filter antenna and communication equipment, wherein the dual-polarized multilayer patch filter antenna comprises a multilayer parasitic structure and adopts differential feed, so that the filter antenna with high roll-off characteristic comprising a 5G frequency band of 3.4-3.7GHZ is realized on the basis of better polarization isolation performance.
The invention adopts the following technical scheme:
a dual-polarized multilayer patch filter antenna comprises four layers of dielectric substrates, a metal reflecting plate and a feed probe, wherein the four layers of dielectric substrates sequentially comprise a first layer of dielectric substrate, a second layer of dielectric substrate, a third layer of dielectric substrate and a fourth layer of dielectric substrate from top to bottom, the upper surface of the first layer of dielectric substrate is a main radiation patch, the lower surface of the first layer of dielectric substrate is an X-shaped parasitic patch, the upper surface of the second layer of dielectric substrate is a first annular parasitic patch, the lower surface of the second layer of dielectric substrate is a second annular parasitic patch, the upper surface of the third layer of dielectric substrate is a third annular parasitic patch, the upper surface of the fourth layer of dielectric substrate is a feed circuit floor, the lower surface of the fourth layer of dielectric substrate is a differential feed circuit, and the metal reflecting plate is arranged below the third layer of dielectric substrate and is positioned on the upper surface of the feed circuit floor;
the feed probe is respectively connected with the X-shaped parasitic patch, the first annular parasitic patch, the second annular parasitic patch, the third annular parasitic patch and the differential feed circuit.
The main radiation patch is a square patch with a hollow middle part, and the hollow part is square.
And four end points of the X-shaped parasitic patch are coupled with the feed probe through the gap.
The first annular parasitic patch, the second annular parasitic patch and the third annular parasitic patch are all square annular structures, and branches are respectively led out from four corners of each square annular structure and connected with the feed probe.
And a circular through hole through which the feed probe passes is formed in the middle of the metal reflecting plate.
The number of the feed probes is four, and the feed probes are all vertically arranged.
The differential feed circuit comprises two one-to-two power dividers, each one-to-two power divider comprises a 50-ohm line width microstrip line and an impedance matching adjusting microstrip line with adjustable length and width, the impedance matching adjusting microstrip line is connected to a feed probe, and the feed probe is connected with another feed probe on the same diagonal line through a 180-degree phase difference adjusting microstrip line.
The peripheral edge of the metal reflecting plate is erected upwards.
In the invention, the first annular parasitic patch, the second annular parasitic patch and the third annular parasitic patch are different in size.
A communication device comprising the dual polarized multi-layer patch filter antenna of any one of claims 1-9.
The invention has the beneficial effects that:
(1) the filtering antenna has controllable size, and can adjust the radiation patch according to the requirementThe size of the cut-off part in the middle of the chip controls the size of the filter antenna, and the size of the antenna in the design is 0.23 lambda0；
(2) The filtering antenna does not comprise a filtering circuit, and filtering characteristics are generated in a parasitic mode, so that the filtering antenna has higher roll-off characteristics and lower pass-band loss, the energy loss of a 5G base station on a radiation antenna can be better reduced, and the operation cost of the base station is reduced;
(3) the invention adopts a simple differential feed power divider, reduces unnecessary loss, and the differential feed mode can bring better polarization isolation effect.
Drawings
FIG. 1 is a schematic structural view of the present invention;
fig. 2 is a diagram of a main radiating patch of the present invention;
FIG. 3 is a schematic diagram of an X-shaped parasitic patch structure of the present invention;
FIG. 4 is a schematic view of a first annular parasitic patch structure of the present invention;
FIG. 5 is a schematic diagram of a second loop parasitic patch structure of the present invention;
FIG. 6 is a schematic diagram of a third annular parasitic patch structure of the present invention;
FIG. 7 is a schematic structural view of a metal reflector according to the present invention;
FIG. 8 is a schematic structural view of a feeder circuit board of the present invention;
FIG. 9 is a schematic diagram of the structure of the differential feed circuit of the present invention;
FIG. 10 is a graph of reflection coefficient S11 versus frequency results for a simulation of the present invention;
FIG. 11 is a graph of transmission coefficient S21 versus frequency results for a simulation of the present invention;
FIG. 12 is a graph of the actual gain versus frequency results of the simulation of the present invention;
FIG. 13 is a graph of actual gain-azimuth theta results from simulations of the present invention.
Detailed Description
The present invention will be described in further detail with reference to examples and drawings, but the present invention is not limited to these examples.
Examples
As shown in fig. 1, the dual-polarized multi-layer patch filter antenna has a symmetrical structure and is linearly polarized at ± 45 °.
The dielectric substrate comprises four layers of dielectric substrates 1, wherein the four layers of dielectric substrates are arranged at intervals at certain intervals and are symmetrical about the center. The first layer of dielectric substrate, the second layer of dielectric substrate, the third layer of dielectric substrate and the fourth layer of dielectric substrate are arranged from top to bottom in sequence.
The upper surface of the first layer of dielectric substrate is a main radiation patch 2, the lower surface of the first layer of dielectric substrate is an X-shaped parasitic patch 3, the upper surface of the second layer of dielectric substrate is a first annular parasitic patch 4, the lower surface of the second layer of dielectric substrate is a second annular parasitic patch 5, the upper surface of the third layer of dielectric substrate is a third annular parasitic patch 6, the upper surface of the fourth layer of dielectric substrate is a feed circuit floor 8, the lower surface of the fourth layer of dielectric substrate is a differential feed circuit 9, and the metal reflecting plate 7 is arranged below the third layer of dielectric substrate and located on the upper surface of the feed circuit floor 8.
As shown in fig. 2, the main radiating patch is in a symmetrical shape, and completes energy radiation of the filtering antenna. The main radiating patch of the present embodiment is square, the middle of the square is hollowed, and the hollowed portion 10 is square, so that the current path is lengthened, and the size of the antenna is miniaturized.
The included angle of the X-shaped parasitic patch is 90 degrees, four end points of the X-shaped parasitic patch are respectively coupled with the four feeding probes 11 through 0.03mm of gaps, and a weaker filtering zero point can be formed on the basis of feeding the main radiation patch.
As shown in fig. 3 to 6, the first annular parasitic patch, the second annular parasitic patch, and the third annular parasitic patch are all square annular structures, in this embodiment, the three annular parasitic patches have different sizes, and the size of the first annular parasitic patch is smaller than that of the third annular parasitic patch. Four microstrip lines are led out from each annular parasitic patch and connected with four feed probes.
In this embodiment, the three annular parasitic patches have different sizes, and each of the three annular parasitic patches generates a stronger parasitic zero point, adjusts the size of the parasitic patch, and can move the positions of the parasitic zero points, so that one of the parasitic zero points is located on the left side of the passband, and the other three parasitic zero points are located on the right side of the passband, thereby realizing the high roll-off characteristic of the filter antenna, and adjusting the weaker filtering zero point generated by the X-shaped parasitic patch to the right edge of the passband, thereby realizing the low-loss design of the right edge of the passband, and the other zero points are located on the right side of the passband, thereby realizing better out.
The invention generates four parasitic zeros, the positions of the four parasitic zeros are controlled by the four parasitic patches relatively independently, the resonant frequency of the parasitic patches corresponds to the frequency position of the parasitic filtering zeros, and the positions of the filtering zeros can be moved by adjusting the sizes of the parasitic patches.
As shown in fig. 7, the metal reflection plate is made of an aluminum material. The peripheral edge of the metal reflecting plate is erected upwards to adjust the beam width and the front-to-back ratio of the antenna unit, four holes corresponding to the positions of the feed probes are dug in the metal reflecting plate, and the metal feed probes penetrate through the holes and are connected to a lower differential circuit to ensure the transmission of signals.
As shown in fig. 8, the feed circuit floor is also hollowed out a circular hole with a corresponding size at the position where the metal reflector plate is hollowed out, and the differential signal from the feed circuit is input into the filter antenna through the feed probe in the middle.
As shown in fig. 9, the differential feeding circuit includes two one-to-two 0-degree and 180-degree phase power dividers; each power divider can be divided into three parts: the differential signal generating device comprises a 50-ohm microstrip connecting line 12, an impedance matching adjusting microstrip line 13 and a 180-degree phase difference adjusting microstrip line 14, wherein output signals of the power divider are respectively connected to a pair of feed probes on two diagonals, and generation of differential signals is completed.
The structures of all layers are connected through four feed probes positioned on the diagonal line of the main radiation patch and are completely symmetrical about the center of the main antenna patch; signals are transmitted to the four layers of parasitic patches from the metal probes through a pair of differential feed circuits with almost consistent performance, and then are coupled to the upper layer of main radiating patches through the dielectric substrate below the uppermost layer of dielectric substrate, so that the radiation of the antenna is completed.
In addition, the invention can simultaneously parasitize a plurality of parasitic elements with different shapes or the same shape under the main parasitic patch, and the parasitic mode can be coupling parasitic or directly connected with the feed probe.
As shown in fig. 10-11, which are graphs of simulation results of reflection coefficient S11-frequency and actual gain-frequency of the plus-minus 45-degree dual-polarized filter antenna provided by an embodiment of the present invention, impedance matching in the pass band is good, the impedance bandwidth is 3.3-3.8GHz, the return loss is less than-15 dB, and the gain in the common operating band is about 6.5 dB. The two sides of the passband have high roll-off filtering characteristics, and the out-of-band rejection of 0-3.1GHz over 12dB and the out-of-band rejection of 4-4.7GHz over 13.5dB are realized.
As shown in fig. 12, which is a graph of a simulation result of transmission coefficient S21-frequency of the positive and negative 45-degree dual-polarized filtering antenna provided by an embodiment of the present invention, two ports in a pass band are well isolated and both are below-30 dB.
As shown in fig. 13, which is a graph of actual gain peak equalized gain-azimuth angle theta of the positive and negative 45-degree dual-polarized filtering antenna according to an embodiment of the present invention, the beam width of 3dB in 3.34 to 3.82GHz within the pass band is 89.6 to 78.99 °, which can meet the requirement of the antenna element wave width of the base station.
A communication device comprises a transmitting system and a receiving system which are formed by the invention.
The embodiment of the invention can adjust the size of the related structure according to the requirement to adapt to the receiving and transmitting equipment of the wireless communication system with different frequency bands, and is particularly suitable for being used in wide and complex communication scenes due to the filtering characteristic of the invention. Meanwhile, the communication equipment formed by the invention is also suitable for integration of wireless mobile communication due to the integration of the filtering characteristic and the radiation characteristic.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (10)
1. A dual-polarization multi-layer patch filter antenna is characterized by comprising four layers of dielectric substrates, a metal reflecting plate and a feed probe, wherein the four layers of dielectric substrates sequentially comprise a first layer of dielectric substrate, a second layer of dielectric substrate, a third layer of dielectric substrate and a fourth layer of dielectric substrate from top to bottom, the upper surface of the first layer of dielectric substrate is a main radiation patch, the lower surface of the first layer of dielectric substrate is an X-shaped parasitic patch, the upper surface of the second layer of dielectric substrate is a first annular parasitic patch, the lower surface of the second layer of dielectric substrate is a second annular parasitic patch, the upper surface of the third layer of dielectric substrate is a third annular parasitic patch, the upper surface of the fourth layer of dielectric substrate is a feed circuit floor, the lower surface of the fourth layer of dielectric substrate is a differential feed circuit, and the metal reflecting plate is arranged below the third layer of dielectric substrate and is positioned on the upper surface of the feed circuit;
the feed probe is respectively connected with the X-shaped parasitic patch, the first annular parasitic patch, the second annular parasitic patch, the third annular parasitic patch and the differential feed circuit.
2. The dual polarized multi-layer patch filter antenna as claimed in claim 1, wherein said main radiating patch is a square patch with a hollow in the middle, and the hollow is a square.
3. The dual polarized multi-layer patch filter antenna according to claim 1, wherein four ends of said X-shaped parasitic patch are coupled to the feed probe through slots.
4. The dual-polarized multi-layer patch filter antenna according to claim 1, wherein the first, second and third annular parasitic patches are all square annular structures, and branches are respectively led out from four corners of each square annular structure and connected with the feed probe.
5. The dual polarized multilayer patch filter antenna according to claim 1, wherein a circular through hole for passing a feed probe is opened in the middle of said metal reflection plate.
6. A dual polarized multi-layered patch filter antenna according to any of claims 1-5, wherein said feed probes are four in number, all arranged vertically.
7. The dual-polarized multi-layer patch filter antenna according to claim 1, wherein the differential feed circuit comprises two one-to-two power dividers, each one-to-two power divider comprises a 50-ohm line-width microstrip line and an impedance matching adjusting microstrip line with adjustable length and width, the impedance matching adjusting microstrip line is connected to a feed probe, and the feed probe is connected with another feed probe on the same diagonal line through a 180-degree phase difference adjusting microstrip line.
8. A dual polarized multi-layer patch filter antenna according to claim 1, wherein said metallic reflector plates are erected upwardly at their peripheral edges.
9. The dual polarized multi-layer patch filter antenna of claim 4, wherein the first, second and third annular parasitic patches are different in size.
10. A communication device, characterized in that it comprises a dual polarized multi-layer patch filter antenna according to any of claims 1-9.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201911180485.6A CN110808458A (en) | 2019-11-27 | 2019-11-27 | Dual-polarization multilayer patch filtering antenna and communication equipment |
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| CN201911180485.6A CN110808458A (en) | 2019-11-27 | 2019-11-27 | Dual-polarization multilayer patch filtering antenna and communication equipment |
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| CN110808458A true CN110808458A (en) | 2020-02-18 |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112038761A (en) * | 2020-08-04 | 2020-12-04 | 广州智讯通信系统有限公司 | High-gain circularly polarized antenna |
| CN112072267A (en) * | 2020-09-15 | 2020-12-11 | 华南理工大学 | Dual-polarized wide-stop-band filtering antenna and communication equipment |
| CN113224518A (en) * | 2021-04-01 | 2021-08-06 | 华南理工大学 | High-gain band-pass dual-polarization filtering patch antenna with compact structure |
| CN114204256A (en) * | 2021-11-29 | 2022-03-18 | 广东工业大学 | Broadband high-isolation patch antenna applied in full duplex and wireless communication equipment |
| CN114512817A (en) * | 2022-04-21 | 2022-05-17 | 华南理工大学 | Dual-polarization filtering antenna, antenna array and radio frequency communication equipment |
| CN114899594A (en) * | 2022-06-27 | 2022-08-12 | 东莞理工学院 | Broadband filtering patch antenna based on double-ring gap structure coupling feed |
| CN114899610A (en) * | 2022-04-21 | 2022-08-12 | 中国人民解放军63660部队 | Broadband microstrip patch antenna working in X wave band |
| CN115473045A (en) * | 2022-11-14 | 2022-12-13 | 四川斯艾普电子科技有限公司 | Miniaturized high-directivity antenna based on thick film and implementation method thereof |
| WO2022267822A1 (en) * | 2021-06-21 | 2022-12-29 | 中兴通讯股份有限公司 | Antenna module, radio frequency device, and base station |
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2019
- 2019-11-27 CN CN201911180485.6A patent/CN110808458A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112038761A (en) * | 2020-08-04 | 2020-12-04 | 广州智讯通信系统有限公司 | High-gain circularly polarized antenna |
| CN112072267A (en) * | 2020-09-15 | 2020-12-11 | 华南理工大学 | Dual-polarized wide-stop-band filtering antenna and communication equipment |
| CN112072267B (en) * | 2020-09-15 | 2021-11-23 | 华南理工大学 | Dual-polarized wide-stop-band filtering antenna and communication equipment |
| CN113224518B (en) * | 2021-04-01 | 2022-12-16 | 华南理工大学 | High-gain band-pass dual-polarization filtering patch antenna with compact structure |
| CN113224518A (en) * | 2021-04-01 | 2021-08-06 | 华南理工大学 | High-gain band-pass dual-polarization filtering patch antenna with compact structure |
| WO2022267822A1 (en) * | 2021-06-21 | 2022-12-29 | 中兴通讯股份有限公司 | Antenna module, radio frequency device, and base station |
| CN114204256A (en) * | 2021-11-29 | 2022-03-18 | 广东工业大学 | Broadband high-isolation patch antenna applied in full duplex and wireless communication equipment |
| CN114512817A (en) * | 2022-04-21 | 2022-05-17 | 华南理工大学 | Dual-polarization filtering antenna, antenna array and radio frequency communication equipment |
| CN114899610A (en) * | 2022-04-21 | 2022-08-12 | 中国人民解放军63660部队 | Broadband microstrip patch antenna working in X wave band |
| CN114512817B (en) * | 2022-04-21 | 2022-08-16 | 华南理工大学 | Dual-polarization filtering antenna, antenna array and radio frequency communication equipment |
| CN114899594A (en) * | 2022-06-27 | 2022-08-12 | 东莞理工学院 | Broadband filtering patch antenna based on double-ring gap structure coupling feed |
| CN114899594B (en) * | 2022-06-27 | 2023-04-14 | 东莞理工学院 | Broadband filtering patch antenna based on double-ring gap structure coupling feed |
| CN115473045A (en) * | 2022-11-14 | 2022-12-13 | 四川斯艾普电子科技有限公司 | Miniaturized high-directivity antenna based on thick film and implementation method thereof |
| CN115473045B (en) * | 2022-11-14 | 2023-02-03 | 四川斯艾普电子科技有限公司 | Miniaturized high-directivity antenna based on thick film and implementation method thereof |
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