CN112467378A - Dual-band MIMO antenna based on decoupling surface of array antenna - Google Patents
Dual-band MIMO antenna based on decoupling surface of array antenna Download PDFInfo
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- CN112467378A CN112467378A CN202011300647.8A CN202011300647A CN112467378A CN 112467378 A CN112467378 A CN 112467378A CN 202011300647 A CN202011300647 A CN 202011300647A CN 112467378 A CN112467378 A CN 112467378A
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- 239000000758 substrate Substances 0.000 claims abstract description 74
- 230000005855 radiation Effects 0.000 claims abstract description 13
- 239000002184 metal Substances 0.000 claims abstract description 8
- 239000003822 epoxy resin Substances 0.000 claims description 3
- 239000006261 foam material Substances 0.000 claims description 3
- 239000000463 material Substances 0.000 claims description 3
- 229920000647 polyepoxide Polymers 0.000 claims description 3
- 238000002955 isolation Methods 0.000 abstract description 19
- 238000004891 communication Methods 0.000 abstract description 8
- 238000010586 diagram Methods 0.000 description 6
- 230000008878 coupling Effects 0.000 description 5
- 238000010168 coupling process Methods 0.000 description 5
- 238000005859 coupling reaction Methods 0.000 description 5
- 238000005516 engineering process Methods 0.000 description 3
- 238000001228 spectrum Methods 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010295 mobile communication Methods 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/52—Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure
- H01Q1/521—Means for reducing coupling between antennas; Means for reducing coupling between an antenna and another structure reducing the coupling between adjacent antennas
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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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q21/00—Antenna arrays or systems
-
- 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
- H01Q5/20—Arrangements for simultaneous operation of antennas on two or more different wavebands, e.g. dual-band or multi-band arrangements characterised by the operating wavebands
- H01Q5/28—Arrangements for establishing polarisation or beam width over two or more different wavebands
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Abstract
本发明公开了一种基于阵列天线解耦表面的双频带MIMO天线，涉及通信系统综合设计中的天线技术领域，解决了目前MIMO通信系统子信道相关性高的技术难题。本发明由并排放置的四个天线单元构成，包括第一基板、第二基板和第三基板自上而下依次层叠；阵列天线解耦表面设置于第一基板上表面，且包含四组金属条带，每组条带由三条长条带和两条短条带组成，长条带和短条带分别用于提高低频和高频段的隔离度，微带馈线和辐射单元设置于第三基板上表面，辐射单元包含一条长半圆弧条带和一条短半圆弧条带，接地板设置于第三基板下表面。本发明可工作在WLAN的2.4/5.2GHz频段，结构简单，成本低，可靠性高，满足MIMO通信系统子信道相关性的要求。
The invention discloses a dual-band MIMO antenna based on an array antenna decoupling surface, relates to the technical field of antennas in the comprehensive design of communication systems, and solves the technical problem of high sub-channel correlation in the current MIMO communication system. The present invention consists of four antenna units placed side by side, including a first substrate, a second substrate and a third substrate stacked in sequence from top to bottom; the decoupling surface of the array antenna is arranged on the upper surface of the first substrate, and includes four groups of metal strips strips, each set of strips consists of three long strips and two short strips, the long strips and the short strips are used to improve the isolation of low frequency and high frequency bands respectively, the microstrip feeder and the radiation unit are arranged on the third substrate On the surface, the radiation unit includes a long semicircular arc strip and a short semicircular arc strip, and the ground plate is arranged on the lower surface of the third substrate. The invention can work in the 2.4/5.2GHz frequency band of WLAN, has simple structure, low cost and high reliability, and meets the requirement of sub-channel correlation of MIMO communication system.
Description
Technical Field
The invention belongs to the technical field of antennas, and particularly relates to a dual-band MIMO antenna based on an array antenna decoupling surface.
Background
With the rapid development of wireless communication technology, spectrum resources are increasingly scarce, and the demands of users on communication rate and communication quality are increasing. The MIMO system adopts a multi-antenna technology at a transmitting end and a receiving end, and improves the receiving quality and the transmission rate of signals by utilizing the spatial freedom of a multipath channel, thereby improving the frequency spectrum utilization rate and the system capacity. Mutual coupling between the MIMO antenna units reduces the isolation of the antennas and increases the correlation of system subchannels.
In recent years, scholars at home and abroad propose various design schemes for improving the isolation between the MIMO antenna units, such as adopting a defected ground structure, loading a resonator, a neutral wire and the like. However, they have the common disadvantage of poor antenna performance, particularly in that the decoupling structure affects the radiation characteristics and matching conditions of the antenna elements, and is difficult to adapt to the fifth generation mobile communication system based on the massive MIMO technology.
How to design a decoupling structure suitable for a large-scale MIMO antenna is a technical problem to be solved. The decoupling surface of the array antenna has the advantages of broadband decoupling and easy design, and is suitable for large-scale MIMO antennas. Therefore, the research on the MIMO antenna based on the decoupling surface of the array antenna is an effective way for solving the technical problem of correlation of the sub-channels of the MIMO system.
Disclosure of Invention
The invention provides a dual-band MIMO antenna based on an array antenna decoupling surface aiming at the problems.
In order to achieve the purpose, the invention adopts the following technical scheme:
a dual-band MIMO antenna based on an array antenna decoupling surface is composed of four antenna units which are arranged side by side and comprises a first substrate, a second substrate and a third substrate which are sequentially stacked from top to bottom; the array antenna decoupling surface is arranged on the upper surface of the first substrate and comprises four groups of metal strips, each group of metal strips consists of three long strips and two short strips, and the long strips and the short strips are arranged at intervals; the microstrip feeder line and the radiation unit are arranged on the upper surface of the third substrate, the radiation unit comprises a long semicircular arc strip and a short semicircular arc strip, and the long semicircular arc strip and the short semicircular arc strip are oppositely arranged at the end part of the microstrip feeder line by taking the microstrip feeder line as a central line; the grounding plate is arranged on the lower surface of the third substrate;
the first substrate, the second substrate, the third substrate and the grounding plate of the four antenna units are connected into a flat plate.
Further, the first substrate, the second substrate and the third substrate are all rectangular dielectric substrates.
Further, the first substrate and the third substrate are made of FR4 epoxy resin material with the dielectric constant of 4.4 and the thickness of 1.6 mm; the second substrate is made of foam material with the dielectric constant of 1.05 and the thickness of 10.4 mm.
Further, the sizes of the first substrate, the second substrate and the third substrate are all 45mm × 175 mm.
Further, the size of the ground plate was 13mm × 175 mm.
Further, the length of the long strip is 40mm, and the width of the long strip is 4.1 mm; the length of the short strip is 14mm, and the width of the short strip is 2.1 mm; the distance between two adjacent long strips is 5.7 mm.
Further, the length of the microstrip feeder line is 17mm, the width of the microstrip feeder line is 3mm, and the characteristic impedance of the microstrip feeder line is 50 Ω; the radius in the long semicircular arc strip of radiating element is 6.8mm, and the radius in the short semicircular arc strip is 2mm, and the width of long semicircular arc strip and short semicircular arc strip is 1 mm.
The array antenna decoupling surface ADS composed of four groups of metal reflection strips is placed above the MIMO antenna and is about half wavelength away from the antenna array, partial reflected waves introduced by the ADS are equal in amplitude and opposite in phase with coupling waves between the MIMO antenna units, the reflected waves and the coupling waves are mutually offset, mutual coupling between the units is reduced, and isolation between the antenna units is improved. The long strip of ADS is used for improving the isolation of the low frequency band, and the short strip is used for improving the isolation of the high frequency band, thereby reducing the correlation of the sub-channels of the MIMO communication system and improving the capacity of the system.
Compared with the prior art, the invention has the following advantages:
1, the decoupling surface of the array antenna is adopted to improve the isolation between the MIMO antenna units, and the decoupling structure does not influence the radiation characteristic and the matching condition of the antenna units, has simple structure and is suitable for large-scale MIMO antennas;
each group of metal strips on the decoupling surface of the array antenna comprises three long strips and two short strips, wherein the long strips are used for improving the isolation of a low frequency band, and the short strips are used for improving the isolation of a high frequency band;
3 the invention can work in 2.4GHz and 5.2GHz bands of WLAN, the relative bandwidth of the two bands is 5.2% and 20.2% respectively, the isolation between units is greater than 15dB, the antenna has good radiation characteristic.
Drawings
Fig. 1 is a schematic structural diagram of a dual-band MIMO antenna based on an array antenna decoupling surface according to the present invention;
fig. 2 is a top view of a first substrate of a dual-band MIMO antenna based on an array antenna decoupling surface according to the present invention;
fig. 3 is a top view of a third substrate of the dual-band MIMO antenna based on an array antenna decoupling surface according to the present invention;
FIG. 4 is S parameters of unit 1 and unit 2 with or without ADS for a dual-band MIMO antenna based on an array antenna decoupling surface according to the present invention;
FIG. 5 is S parameters of unit 2 and unit 3 with or without ADS for a dual-band MIMO antenna based on an array antenna decoupling surface according to the present invention;
FIG. 6 is S parameters of unit 1 and unit 3 when the dual-band MIMO antenna based on the array antenna decoupling surface of the present invention has or has not ADS;
FIG. 7 is S parameters of unit 1 and unit 4 with or without ADS for a dual-band MIMO antenna based on an array antenna decoupling surface according to the present invention;
FIG. 8 is a radiation pattern of a dual-band MIMO antenna at 2.4GHz based on an array antenna decoupling surface according to the present invention;
fig. 9 is a radiation pattern of the dual-band MIMO antenna based on the decoupling surface of the array antenna at 5.2GHz in accordance with the present invention.
The antenna comprises a first substrate, a second substrate, a third substrate, a 4-array antenna decoupling surface, a long strip, a short strip, a 5-microstrip feeder, a 6-radiating element, a long semicircular strip, a 62-short semicircular strip and a 7-grounding plate, wherein the first substrate is 1-the first substrate, the second substrate is 2-the second substrate, the third substrate is 3-the 4-array antenna decoupling surface, and the second substrate is 7-the grounding plate.
Detailed Description
Embodiments of the present invention will be described in further detail with reference to the accompanying drawings.
Example 1
As shown in fig. 1, 2 and 3, a dual-band MIMO antenna based on an array antenna decoupling surface is composed of four antenna units arranged side by side, and includes a first substrate 1, a second substrate 2 and a third substrate 3 stacked in sequence from top to bottom; the array antenna decoupling surface 4 is arranged on the upper surface of the first substrate 1, the array antenna decoupling surface 4 comprises four groups of metal strips, each group of metal strips consists of three long strips 41 and two short strips 42, and the long strips 41 and the short strips 42 are arranged at intervals; the microstrip feeder line 5 and the radiating element 6 are arranged on the upper surface of the third substrate, the radiating element 6 comprises a long semicircular arc strip 61 and a short semicircular arc strip 62, and the long semicircular arc strip 61 and the short semicircular arc strip 62 are oppositely arranged at the end part of the microstrip feeder line 5 by taking the microstrip feeder line 5 as a central line; the grounding plate 7 is arranged on the lower surface of the third substrate; the first substrate 1, the second substrate 2, the third substrate 3 and the grounding plate 7 of the four antenna units are connected into a flat plate.
Further, the first substrate 1, the second substrate 2 and the third substrate 3 are all rectangular dielectric substrates.
Further, the first substrate 1 and the third substrate 3 are made of FR4 epoxy resin material with dielectric constant of 4.4 and thickness of 1.6 mm; the second substrate 2 is made of foam material with the dielectric constant of 1.05 and the thickness of 10.4 mm.
Further, the first substrate 1, the second substrate 2, and the third substrate 3 each have a size of 45mm × 175 mm.
Further, the size of the ground plate 7 is 13mm × 175 mm.
Further, the long strips 41 have a length of 40mm and a width of 4.1 mm; the short strip 42 is 14mm long and 2.1mm wide; the distance between two adjacent long strips 41 is 5.7 mm.
Further, the length of the microstrip feeder line 5 is 17mm, the width is 3mm, and the characteristic impedance is 50 Ω; the inner radius of the long semicircular arc strip 61 of the radiation unit 6 is 6.8mm, the inner radius of the short semicircular arc strip 62 is 2mm, and the widths of the long semicircular arc strip 61 and the short semicircular arc strip 62 are both 1 mm.
The advantages of the invention can be further illustrated by simulation results. Modeling analysis is carried out on the dual-band MIMO antenna based on the array antenna decoupling surface in the embodiment, the array antenna decoupling surface ADS generates partial reflected waves which are equal in amplitude and opposite in phase with the coupled waves between the antenna units, mutual coupling between the antenna units is reduced, isolation between the antenna units is improved, and then correlation of sub-channels of the MIMO communication system is reduced.
Fig. 4-7 show the reflection coefficient and isolation of the dual-band MIMO antenna with or without loading ADS according to the present invention, where the abscissa represents the frequency variable in GHz and the ordinate represents the amplitude variable in dB. As can be seen, the antenna operates in the 2.4GHz and 5.2GHz bands of the WLAN. The impedance bandwidths of the antenna without loading the ADS in two frequency bands are respectively 2.4-2.64GHz (9.5%) and 4.97-5.81GHz (15.6%), and the isolation between adjacent antenna units ( units 1 and 2, units 2 and 3) is poor; the impedance bandwidths of the antenna loaded with ADS are 2.37-2.47GHz (4.1%) and 4.9-6GHz (20.2%) respectively in the two frequency bands, the isolation between unit 1 and unit 2 increases from 12.3dB and 13.9dB to 15.7dB and 15.3dB, the isolation between unit 2 and unit 3 increases from 10.1dB and 12.5dB to 15.5dB and 15.8dB, the isolation between unit 1 and unit 3 increases from 19dB and 17.3dB to 21.9dB and 23.9dB, the isolation between unit 1 and unit 4 decreases from 21.4dB to 19dB in the low frequency band, and the isolation increases from 18.6dB to 22.1dB in the high frequency band. Therefore, the isolation of the MIMO antenna loaded with the ADS between the two frequency band units is larger than 15 dB.
Fig. 8-9 show normalized radiation patterns at two resonant frequencies for a dual-band MIMO antenna based on an array antenna decoupling surface in accordance with the present invention. As can be seen from the figure, at 2.4GHz, the E-plane directional diagram of the antenna is in a 8 shape, and the H-plane directional diagram is approximately omnidirectional; at 5.2GHz, the directional diagram of the antenna is slightly deteriorated, the E-plane directional diagram is close to the 8 shape, and the H-plane directional diagram is approximate to the omnidirectional.
Those skilled in the art will appreciate that the invention may be practiced without these specific details. Although illustrative embodiments of the present invention have been described above to facilitate the understanding of the present invention by those skilled in the art, it should be understood that the present invention is not limited to the scope of the embodiments, and various changes may be made apparent to those skilled in the art as long as they are within the spirit and scope of the present invention as defined and defined by the appended claims, and all matters of the invention which utilize the inventive concepts are protected.
Claims (7)
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011300647.8A CN112467378A (en) | 2020-11-19 | 2020-11-19 | Dual-band MIMO antenna based on decoupling surface of array antenna |
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| CN202011300647.8A CN112467378A (en) | 2020-11-19 | 2020-11-19 | Dual-band MIMO antenna based on decoupling surface of array antenna |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113471718A (en) * | 2021-05-17 | 2021-10-01 | 西安电子科技大学 | Different-frequency self-decoupling millimeter wave array antenna |
| CN113517572A (en) * | 2021-03-25 | 2021-10-19 | 西安电子科技大学 | A high isolation dual frequency dual polarized array antenna for millimeter wave band |
| CN113517558A (en) * | 2021-03-24 | 2021-10-19 | 西安电子科技大学 | High-isolation 5G base station antenna and wireless communication terminal |
| CN113644437A (en) * | 2021-08-19 | 2021-11-12 | 深圳市道通智能汽车有限公司 | Microstrip antenna and millimeter wave radar |
| WO2022233212A1 (en) * | 2021-05-06 | 2022-11-10 | 中兴通讯股份有限公司 | Decoupling device and decoupling method |
| CN117458147A (en) * | 2023-12-08 | 2024-01-26 | 深圳市中天迅通信技术股份有限公司 | A UWB positioning antenna and its production method |
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| CN211605403U (en) * | 2020-03-25 | 2020-09-29 | 山东农业大学 | Double-frequency printed monopole antenna with resonant branches and suitable for 5G communication |
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2020
- 2020-11-19 CN CN202011300647.8A patent/CN112467378A/en active Pending
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Non-Patent Citations (1)
| Title |
|---|
| 陈洁: "基于ADS的阵列天线的研究与设计", 《万方论文库》 * |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113517558A (en) * | 2021-03-24 | 2021-10-19 | 西安电子科技大学 | High-isolation 5G base station antenna and wireless communication terminal |
| CN113517572A (en) * | 2021-03-25 | 2021-10-19 | 西安电子科技大学 | A high isolation dual frequency dual polarized array antenna for millimeter wave band |
| WO2022233212A1 (en) * | 2021-05-06 | 2022-11-10 | 中兴通讯股份有限公司 | Decoupling device and decoupling method |
| CN113471718A (en) * | 2021-05-17 | 2021-10-01 | 西安电子科技大学 | Different-frequency self-decoupling millimeter wave array antenna |
| CN113644437A (en) * | 2021-08-19 | 2021-11-12 | 深圳市道通智能汽车有限公司 | Microstrip antenna and millimeter wave radar |
| CN117458147A (en) * | 2023-12-08 | 2024-01-26 | 深圳市中天迅通信技术股份有限公司 | A UWB positioning antenna and its production method |
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Application publication date: 20210309 |