CN117691347A - Miniaturized dual-frenquency bluetooth fractal antenna - Google Patents
Miniaturized dual-frenquency bluetooth fractal antenna Download PDFInfo
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- CN117691347A CN117691347A CN202311705793.2A CN202311705793A CN117691347A CN 117691347 A CN117691347 A CN 117691347A CN 202311705793 A CN202311705793 A CN 202311705793A CN 117691347 A CN117691347 A CN 117691347A
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- 239000000758 substrate Substances 0.000 claims abstract description 80
- 230000005855 radiation Effects 0.000 claims abstract description 52
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical group [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 13
- 230000008878 coupling Effects 0.000 claims abstract description 10
- 238000010168 coupling process Methods 0.000 claims abstract description 10
- 238000005859 coupling reaction Methods 0.000 claims abstract description 10
- 230000002093 peripheral effect Effects 0.000 claims abstract description 10
- 229910001218 Gallium arsenide Inorganic materials 0.000 claims description 7
- JBRZTFJDHDCESZ-UHFFFAOYSA-N AsGa Chemical compound [As]#[Ga] JBRZTFJDHDCESZ-UHFFFAOYSA-N 0.000 claims description 6
- PEZNEXFPRSOYPL-UHFFFAOYSA-N (bis(trifluoroacetoxy)iodo)benzene Chemical group FC(F)(F)C(=O)OI(OC(=O)C(F)(F)F)C1=CC=CC=C1 PEZNEXFPRSOYPL-UHFFFAOYSA-N 0.000 claims description 5
- 230000005540 biological transmission Effects 0.000 claims description 4
- 238000004804 winding Methods 0.000 claims 2
- 238000013461 design Methods 0.000 abstract description 7
- 229910052802 copper Inorganic materials 0.000 abstract description 5
- 239000010949 copper Substances 0.000 abstract description 5
- 230000000191 radiation effect Effects 0.000 abstract description 3
- 230000000694 effects Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 4
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000010295 mobile communication Methods 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02D—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN INFORMATION AND COMMUNICATION TECHNOLOGIES [ICT], I.E. INFORMATION AND COMMUNICATION TECHNOLOGIES AIMING AT THE REDUCTION OF THEIR OWN ENERGY USE
- Y02D30/00—Reducing energy consumption in communication networks
- Y02D30/70—Reducing energy consumption in communication networks in wireless communication networks
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Abstract
The invention provides a miniaturized double-frequency Bluetooth fractal antenna, which comprises a first substrate layer and a second substrate layer, wherein an air layer is arranged between the first substrate layer and the second substrate layer; the first substrate layer comprises a first radiation patch and a support column, the second substrate layer comprises a second radiation patch and a peripheral copper wire structure arranged at the side edge of the second substrate layer, the first substrate layer further comprises a grounding wire, and the first radiation patch of the first substrate layer adopts a fractal structure; the radiation structure of the double-layer plate is adopted, the first radiation patch is designed by the Hilbert fractal structure, the curve structure can realize multimode resonance, so that the characteristic of broadband multifrequency is obtained, and meanwhile, the mutual coupling influence between reverse flowing currents between adjacent patches can be eliminated by the design of the double-layer overlapped fractal structure, the radiation effect is greatly enhanced, and the requirement of miniaturization is met; the periphery of the second substrate layer adopts a copper sheet surrounding structure to enhance radiation efficiency, and excites various resonance modes so as to further expand bandwidth.
Description
Technical Field
The invention relates to the technical field of antennas, in particular to a miniaturized dual-frequency Bluetooth fractal antenna.
Background
With the rapid development of wireless communication technology nowadays, while the popularity of various terminal devices in daily life is rapidly increasing, the requirements of mobile communication devices are increasingly tending to be integrated, miniaturized and low-cost, so how to design miniaturized high-performance antennas is a focus of research. In order to meet the requirements of portability, multifunction and high performance, the built-in bluetooth antenna needs to have the characteristics of small volume, light weight and strong adaptability, and meanwhile, the performances such as bandwidth, gain and the like cannot be obviously reduced.
In the current mobile communication system, along with the development of the portability of equipment, the miniaturization of an antenna is also more and more important, but the antenna has the functions of meeting the requirement of 2.4HGz and 5GHz multi-resonance point operation while being miniaturized, and the current length and the radiation area are greatly reduced due to the extremely small size, so that the bandwidth and the peak gain of the resonance point of the common miniaturized antenna are not satisfactory. In addition, the design of the miniaturized antenna is generally limited, and the original antenna can not be slightly changed according to the index requirement so as to achieve the desired effect.
Disclosure of Invention
Aiming at the defects in the technology, the invention provides a miniaturized double-frequency Bluetooth fractal antenna, which comprises a first substrate layer and a second substrate layer which are sequentially arranged in a layering manner, wherein an air layer is arranged between the first substrate layer and the second substrate layer; the first substrate layer comprises a first radiation patch and a support column, the second substrate layer comprises a second radiation patch and a peripheral copper wire structure arranged at the side edge of the second substrate layer, the first substrate layer further comprises a grounding wire, and the first radiation patch of the first substrate layer adopts a fractal structure.
In one embodiment, the fractal of the first radiating patch is a hilbert fractal.
In one embodiment, the first radiation patch uses any side of the first substrate layer as an end, and the first radiation patch is wound back in the board surface of the first substrate layer to form an outer layer structure with a first shape, and then is wound back to the inner side of the outer layer structure to form an inner layer structure with the same shape.
In one embodiment, the circuit further comprises a grounding shorting line, wherein the grounding shorting line is a PIFA structure.
In one embodiment, the first radiating patch includes a transmission line feed that is at least 50 ohms.
In one embodiment, the patch width of the first radiating patch is at least 0.25mm and the outer layer structure and the inner layer structure of the first radiating patch are spaced apart by a distance of at least 0.22mm.
In one embodiment, the second radiating patches are provided in plurality, and the second radiating patches use coupling feeding.
In one embodiment, the first substrate layer is 0.8mm-1mm, the second substrate layer is 0.4mm-0.6mm, and the air layer is 0.2mm-0.4mm.
In one embodiment, the first substrate layer and the second substrate layer are gallium arsenide dielectric substrate layers.
In one embodiment, the peripheral copper wire structure is wrapped around the side edge of the second base plate and is an asymmetric wrapped structure.
The beneficial effects of the invention are as follows: compared with the prior art, the miniaturized double-frequency Bluetooth fractal antenna is characterized by comprising a first substrate layer and a second substrate layer which are sequentially arranged in a layering manner, wherein an air layer is arranged between the first substrate layer and the second substrate layer; the first substrate layer comprises a first radiation patch and a support column, the second substrate layer comprises a second radiation patch and a peripheral copper wire structure arranged at the side edge of the second substrate layer, the first substrate layer further comprises a grounding wire, and the first radiation patch of the first substrate layer adopts a fractal structure; the radiation structure of the double-layer plate is adopted, the first radiation patch is designed by the Hilbert fractal structure, the curve structure can realize multimode resonance, so that the characteristic of broadband multifrequency is obtained, and meanwhile, the mutual coupling influence between reverse flowing currents between adjacent patches can be eliminated by the design of the double-layer overlapped fractal structure, the radiation effect is greatly enhanced, and the requirement of miniaturization is met; the periphery of the second substrate layer adopts a copper sheet surrounding structure to enhance radiation efficiency, and excites various resonance modes so as to further expand bandwidth; in addition, compared with the common double-layer plate, the peripheral copper sheet effectively enhances the gain of the antenna, overcomes the defect that the radiation pattern of the multi-frequency antenna is not ideal enough, and achieves better radiation omnidirectionality in better low frequency.
Drawings
Fig. 1 is a hierarchical structure diagram of the present invention.
Fig. 2 is a diagram of a first substrate layer structure according to the present invention.
Fig. 3 is a diagram of a second substrate layer structure according to the present invention.
Fig. 4 is a graph showing the performance of the return loss |s11| according to the present invention.
Fig. 5 is a gain performance diagram of the present invention.
Fig. 6 is a graph of 2.4GHz radiation direction performance of the present invention.
Fig. 7 is a graph of the 5.5GHz radiation direction performance of the present invention.
Detailed Description
In order to more clearly illustrate the invention, the invention is further described below with reference to the accompanying drawings.
Technical solutions in the embodiments of the present application will be clearly and comprehensively described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to fall within the scope of the invention.
In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the apparatus or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or the inclusion of a number of indicated features. Thus, a feature defining "a first" or "a second" may include, either explicitly or implicitly, one or more of the described features. In the description of the present invention, the meaning of "a plurality" is two or more unless explicitly defined otherwise.
In the application, the term "exemplary" is used to mean "serving as an example, instance, or illustration. Any embodiment described herein as exemplary is not necessarily to be construed as preferred or advantageous over other embodiments. The following description is presented to enable any person skilled in the art to make and use the invention. In the following description, details are set forth for purposes of explanation. It will be apparent to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well-known structures and processes have not been described in detail so as not to obscure the description of the invention with unnecessary detail. Thus, the present invention is not intended to be limited to the embodiments shown, but is to be accorded the widest scope consistent with the principles disclosed herein.
Referring to fig. 1-3, the miniaturized dual-frequency bluetooth fractal antenna comprises a first substrate layer and a second substrate layer which are sequentially arranged in a layering manner, wherein an air layer is arranged between the first substrate layer and the second substrate layer; the first substrate layer comprises a first radiation patch and a support column, the second substrate layer comprises a second radiation patch and a peripheral copper wire structure arranged at the side edge of the second substrate layer, the first substrate layer further comprises a grounding wire, and the first radiation patch of the first substrate layer adopts a fractal structure; in this embodiment, three-frequency function is realized through the miniaturized antenna of the first layer base plate layer +0.2mm thickness air bed +0.4mm thickness second layer base plate layer "of structure for 0.8mm thickness, broken through the constraint of traditional miniaturized blue ear antenna individual layer radiation board, with the effective thickness control in acceptable degree when reducing the antenna size, thereby delay that produces different degrees through the electromagnetic wave propagation velocity difference in different medium reaches the effect of shifting the phase, this product combines the phase shifter into double-deck radiation board, possess better radiation pattern when satisfying antenna frequency channel requirement.
Preferably, according to the miniaturized dual-frequency Bluetooth fractal antenna provided by the invention, the radiation patterns of each frequency band can be freely adjusted according to requirements by changing the height of an intermediate air layer, namely the distance between two layers of dielectric substrates, so that the applicable scene and the degree of freedom of the antenna are greatly increased.
In this embodiment, the second substrate layer is added at a distance of 0.2mm (changeable) from the first substrate layer, and is made of gallium arsenide, so that the effect of a simple phase shifter is achieved through the structure of a gallium arsenide dielectric substrate-air-gallium arsenide dielectric substrate, and the radiation pattern can be moderately changed. Meanwhile, the second radiation patch on the first substrate layer is fed by the coupling of the first radiation patch, so that the bandwidth of high frequency is increased, the double-frequency resonance point is improved, and the frequency bands of 2.2-2.48GHz and 5.2-5.7GHz are completely covered.
In one embodiment, the fractal structure of the first radiation patch is a hilbert fractal structure; in this embodiment, the first substrate layer adopts a CPW coplanar waveguide feeding mode, and the first radiating patch of the hilbert fractal structure and the grounding short-circuit line of the inverted-F design structure (PIFA structure) form a main radiating patch, which is attached to a special material substrate of a gallium arsenide medium, which is a high dielectric constant material, so that the area of the patch is greatly reduced while the performance is maintained, and the low-profile effect is achieved.
In one embodiment, the first radiation patch takes any side of the first substrate layer as an end, and the first radiation patch is wound in a plate surface extending to the first substrate layer to form an outer layer structure with a first shape, and then is wound to the inner side of the outer layer structure to form an inner layer structure with the same shape; the first radiation patch is wound back, the inner layer structure and the outer layer structure form a double-layer superposition structure, the current flow direction in the patch is guaranteed to be the same, mutual interference coupling generated by opposite currents between adjacent patches is effectively eliminated, and meanwhile, the current length in the patch is remarkably increased, so that the required resonant frequency is achieved, and the radiation efficiency is enhanced.
In one embodiment, the circuit further comprises a grounding shorting line, wherein the grounding shorting line is a PIFA structure; the grounding short-circuit line is mainly responsible for effectively reducing the size of the antenna to reach a low-profile structure by referring to the PIFA antenna structure; a plane radiating unit is adopted as a radiator, a large ground is adopted as a reflecting surface, and two Pin pins which are close to each other are arranged on the radiator and are respectively used for grounding and serving as a feed point; when the ground and feed lines are only a thin line, the equivalent radio frequency distributed inductance is large, while the distributed capacitance on the leads is small, which means that the antenna has a high Q value and a narrow frequency band. According to the relation between the Q value and the bandwidth of the electrically small antenna, the way to increase the bandwidth is to decrease the Q value, so that the distributed capacitance and the distributed inductance can be increased by replacing the grounding wire and the feeding wire with metal sheets with certain widths, thereby increasing the bandwidth of the antenna.
In one embodiment, the first radiating patch includes a transmission line feed that is at least 50 ohms.
In one embodiment, the patch width of the first radiating patch is at least 0.25mm and the outer layer structure and the inner layer structure of the first radiating patch are spaced apart by a distance of at least 0.22mm; the first radiation patch with the Hilbert fractal structure is mainly responsible for bandwidth resonance of high-frequency 5.5GHz-5.7GHz frequency bands, effective radiation and low-frequency 2.4GHz resonance with narrower bandwidth; the strip-shaped patches are obtained through multiple optimization, the width of each strip-shaped patch is 0.25mm, and the distance between adjacent patches is 0.22mm. The double-layer overlapped first radiation patches enable currents in adjacent patches to flow in the same direction, eliminate mutual interference coupling between reverse currents, lengthen current length and enhance radiation efficiency, and therefore resonance points of two frequency bands of 2.4GHz and 5.5GHz are provided.
In one embodiment, the second radiating patch is provided in plurality, and the second radiating patch is fed by coupling.
In one embodiment, the first substrate layer is 0.8mm-1mm, the second substrate layer is 0.4mm-0.6mm, and the air layer is 0.2mm-0.4mm; the second substrate layer is mainly divided into two parts, and the second substrate layer is 10.6mm×7.9mm×0.4mm 3 The peripheral copper wire structure is wrapped on the side edge of the second base plate and is of an asymmetric wrapping structure, and the peripheral wrapping is performed on copper wires with asymmetric thickness of 0.2mm, so that the radiation efficiency is effectively increased, and the bandwidth is improved; the structure with the left side of 6.2mm and the right side of 2.2mm is beneficial to improving the direction of the antenna; the second radiation patch of the second substrate layer adopts coupling feed, and the special structural design effectively increases the resonance bandwidth of low frequency and improves the gain of double frequency.
In one embodiment, the first substrate layer and the second substrate layer are gallium arsenide dielectric substrate layers.
To better demonstrate the effects of the present application, test charts of FIGS. 4-7 are attached to further illustrate the actions and effects of the products of the present application.
Fig. 4 is a graph showing the effects of the |s-11| parameters of the antenna, and it can be seen that the antenna satisfies 2.31GHz-2.48GHz,4.00-4.20GHz,5.22-5.74GHz (S11 < -6 dB).
Fig. 5 is a graph of gain peaks at corresponding frequencies of the antenna, and it can be seen from the graph that the peak gains are respectively > 2.5dBi, > 4dBi, > 5.2dBi in the corresponding frequency bands.
Fig. 6-7 show radiation patterns of the antenna in the low frequency band (2.4 GHz) and the high frequency band (5.5 GHz), which have better radiation omnidirectionality and are affected by the triangular radiation patch of the second layer, and the 90-degree direction of the antenna has no obvious recess.
The invention has the advantages that:
the radiation structure of the double-layer plate is adopted, the first radiation patch is designed by the Hilbert fractal structure, the curve structure can realize multimode resonance, so that the characteristic of broadband multifrequency is obtained, and meanwhile, the mutual coupling influence between reverse flowing currents between adjacent patches can be eliminated by the design of the double-layer overlapped fractal structure, the radiation effect is greatly enhanced, and the requirement of miniaturization is met; the periphery of the second substrate layer adopts a copper sheet surrounding structure to enhance radiation efficiency, and excites various resonance modes so as to further expand bandwidth.
The above disclosure is only a few specific embodiments of the present invention, but the present invention is not limited thereto, and any changes that can be thought by those skilled in the art should fall within the protection scope of the present invention.
Claims (10)
1. The miniature dual-frequency Bluetooth fractal antenna is characterized by comprising a first substrate layer and a second substrate layer which are sequentially arranged in a layering manner, wherein an air layer is arranged between the first substrate layer and the second substrate layer; the first substrate layer comprises a first radiation patch and a support column, the second substrate layer comprises a second radiation patch and a peripheral copper wire structure arranged at the side edge of the second substrate layer, the first substrate layer further comprises a grounding wire, and the first radiation patch of the first substrate layer adopts a fractal structure.
2. The miniaturized dual-band bluetooth fractal antenna according to claim 1, wherein said fractal structure of said first radiating patch is a hilbert fractal structure.
3. The miniaturized dual-frequency bluetooth fractal antenna according to claim 2, wherein the first radiating patch is formed by winding an outer layer structure with a first shape in a plane extending to the first substrate layer with any side of the first substrate layer as an end, and then winding the outer layer structure to the inner side of the outer layer structure to form an inner layer structure with the same shape.
4. The miniaturized dual-band bluetooth fractal antenna according to claim 3, further comprising a short-circuit line to ground, said short-circuit line to ground being a PIFA structure.
5. The miniaturized dual-band bluetooth fractal antenna according to claim 4, wherein said first radiating patch includes a transmission line feed, said transmission line feed being at least 50 ohms.
6. A miniaturized dual-band bluetooth fractal antenna according to claim 3, wherein said first radiating patch has a patch width of at least 0.25mm and said outer layer structure and said inner layer structure of said first radiating patch are spaced apart by a distance of at least 0.22mm.
7. The miniaturized dual-frequency bluetooth fractal antenna according to claim 1, wherein a plurality of second radiating patches are provided, and the second radiating patches are fed by coupling.
8. The miniaturized dual-frequency bluetooth fractal antenna according to claim 1, wherein said first substrate layer is 0.8mm-1mm, said second substrate layer is 0.4mm-0.6mm, and said air layer is 0.2mm-0.4mm.
9. The miniaturized dual-band bluetooth fractal antenna according to claim 1, wherein said first and second substrate layers are gallium arsenide dielectric substrate layers.
10. The miniaturized dual-band bluetooth fractal antenna according to claim 1, wherein said peripheral copper wire structure is wrapped around the side edge of said second base plate and is an asymmetric wrapping structure.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311705793.2A CN117691347A (en) | 2023-12-12 | 2023-12-12 | Miniaturized dual-frenquency bluetooth fractal antenna |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311705793.2A CN117691347A (en) | 2023-12-12 | 2023-12-12 | Miniaturized dual-frenquency bluetooth fractal antenna |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117691347A true CN117691347A (en) | 2024-03-12 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311705793.2A Pending CN117691347A (en) | 2023-12-12 | 2023-12-12 | Miniaturized dual-frenquency bluetooth fractal antenna |
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| Country | Link |
|---|---|
| CN (1) | CN117691347A (en) |
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2023
- 2023-12-12 CN CN202311705793.2A patent/CN117691347A/en active Pending
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