CN114976673B - Dual-polarized double-notch independently adjustable structural wave absorber - Google Patents
Dual-polarized double-notch independently adjustable structural wave absorber Download PDFInfo
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- CN114976673B CN114976673B CN202210242359.4A CN202210242359A CN114976673B CN 114976673 B CN114976673 B CN 114976673B CN 202210242359 A CN202210242359 A CN 202210242359A CN 114976673 B CN114976673 B CN 114976673B
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- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q17/00—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems
- H01Q17/008—Devices for absorbing waves radiated from an antenna; Combinations of such devices with active antenna elements or systems with a particular shape
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Abstract
The invention relates to the technical field of communication, in particular to a dual-polarized double-notch independently adjustable structural wave absorber which mainly comprises a three-layer structure, wherein the wave absorbing structure, an air filling layer and a notch structure are sequentially arranged from top to bottom; the air filling layer is positioned in the middle of the structure and is composed of an air medium; the notch structure is located at the bottom of the structure and comprises a medium substrate, a metal square double-ring unit and an L-shaped parasitic structure which are located on the upper layer of the medium substrate and a metal floor which is located on the lower layer of the medium substrate, the notch absorber can achieve the 4.8GHz-15GHz wave absorbing bandwidth, two notch bands are achieved through the addition of the square double-ring structure, the two notch bands are polarization insensitive, and independent adjustment of the notch band range can be achieved through simple parameter adjustment.
Description
Technical Field
The invention relates to the technical field of communication, in particular to a dual-polarized double-notch independently adjustable structural wave absorber.
Background
With the continuous development of wireless communication, the electromagnetic environment is more and more complex, the interference between devices is more and more serious, and the interference of electromagnetic waves can cause drastic deterioration to the devices and the communication quality. In addition, the military detection of the target basically uses radar to radiate electromagnetic waves, receives the electromagnetic waves reflected by the target body to confirm the position of the target body, and military equipment such as stealth fighters and the like need to reduce the reflection of the electromagnetic waves to realize stealth effects, so that wave absorbing materials are generated. The traditional wave absorbing material is generally manufactured by using high-loss substances such as ferrite, metal micropowder, graphite, silicon carbide and the like, and external electromagnetic waves are incident on the materials and can be quickly attenuated, but the traditional wave absorbing material has the problems of low recycling rate, limited absorption frequency band range, large size, poor high-temperature characteristic and the like.
The structural electromagnetic absorber has the advantages of wide absorption bandwidth, low cost, low profile, small size and the like, and brings great attention to students at home and abroad. The structural wave absorber utilizes the periodic structural units of specific metal patterns to realize the absorption of external electromagnetic waves, and the current research is mainly focused on the aspects of wave absorption bandwidth, low profile, wide incidence angle and the like. The university of western-style electronic technology has published a structural wave-absorbing material (the university of western-style electronic technology, structural wave-absorbing material, application number CN201110102712.0, application date 2011.04.22), which implements two wave-absorbing bands with an arrowhead-shaped metal pattern and a metal floor on the back, the wave-absorbing rate being approximately 1; the Shenzhen city ring wave technology Limited liability company discloses a wave absorbing structure (Shenzhen city ring wave technology Limited liability company, application number CN201910713580.1, application date 2019.08.02), a wave absorbing function for specific frequency is realized by utilizing a multi-layer metal structure, and the absorption effect of 2.5GHz-4GHz can be realized by changing parameters. Although the two wave-absorbing structures can realize wave-absorbing effect within a certain range, the wave-absorbing bandwidth is still very narrow, and the wave-absorbing structure is still not applicable to certain scenes needing broadband wave absorption.
In recent years, a simple broadband wave-absorbing structure is mature, specific functions are realized on the broadband wave-absorbing structure, a research hot spot is gradually formed, a notch frequency band is formed in a broadband wave-absorbing frequency band, and the broadband wave-absorbing structure can realize total reflection of specific frequencies, can be integrated with an antenna, and can be used as a functional floor of the antenna to reduce the radar scattering cross section of the antenna. For example, "A Band-Notched Absorber Designed With High Notch-Band-Edge selection" (IEEE Transactions on Antennas and Propagation, vol.65, no. 7, pp. 3560-3567) published in electronic technology university Mei Peng 2017 is to add metal slits and metal grids to a broadband structural wave absorber, and to realize a notch Band of 8.2GHz-9.8GHz within a wave-absorbing bandwidth of 4.8GHz-16 GHz. However, the above research still has the defects that the function implementation is only aimed at single polarized electromagnetic waves, and the notch frequency is only one, so that the method is difficult to apply to the application scene of the dual-frequency dual-polarized antenna required by the communication at present.
Aiming at the technical problems, the invention designs the structural wave absorber which has wide frequency band, low profile, dual polarization and double notch frequency band and is independently adjustable. The wave absorber can achieve 4.8GHz-15GHz wave absorbing bandwidth, two notch frequency bands, namely 7.2GHz-7.6GHz and 13.1Hz-13.5GHz, are achieved through adding the square double-ring structure, the two notch frequency bands have polarization insensitivity, namely TE waves and TM waves can meet the characteristics, and independent adjustment of the notch frequency band range can be achieved through simply adjusting parameters.
Disclosure of Invention
First, the technical problem to be solved
The dual-polarized dual-notch independently adjustable structural wave absorber solves the problem that the function of the wave absorber at the present stage is realized only for single-polarized electromagnetic waves, only one notch band is needed, and the wave absorber is difficult to apply to the application scene of the dual-frequency dual-polarized antenna required by the communication at present.
(II) technical scheme
The dual-polarized double-notch independently adjustable structural wave absorber mainly comprises a three-layer structure, wherein the wave absorbing structure, an air filling layer and a notch structure are sequentially arranged from top to bottom, and the wave absorbing structure is positioned at the top of the structure and comprises a medium substrate, a metal rectangular patch and a resistor which are positioned at the upper layer of the medium substrate, a metalized through hole positioned in the medium substrate, a metal bow tie type dipole unit and a resistor which are positioned at the lower layer of the medium substrate; the air filling layer is positioned in the middle of the structure and is composed of an air medium; the notch structure is positioned at the bottom of the structure and comprises a dielectric substrate, a metal square double-ring unit and an L-shaped parasitic structure which are positioned at the upper layer of the dielectric substrate, and a metal floor positioned at the lower layer of the dielectric substrate.
As the preferable technical scheme, the metal bow tie type dipole unit consists of four completely consistent bow tie type metal patches, a resistor is welded between the left bow tie type metal patch and the right bow tie type metal patch, and the middle of the upper bow tie type metal patch and the lower bow tie type metal patch are disconnected and connected with a metalized through hole.
As the preferable technical scheme, the metallized through holes are composed of twelve metallized cylinders and are symmetrically distributed and used for connecting the metal rectangular patch at the upper layer of the top dielectric substrate and the metal bow tie type metal patch at the lower layer.
As the preferable technical scheme, the metal rectangular patch consists of two small metal rectangular patches which are symmetrically distributed, a gap is reserved in the middle of the metal rectangular patches and is used for being connected with a resistor, and the small metal rectangular patches are respectively connected with six metallized through holes.
As the preferable technical scheme, the metal square double-ring unit consists of two nested metal square rings, wherein an inner small metal square ring is used for realizing a high-frequency notch point, and an outer large metal square ring is used for realizing a low-frequency notch point.
As an optimal technical scheme, the L-shaped parasitic structure is positioned around the metal square double-ring unit, and a high-frequency notch point is realized through coupling with the metal square double-ring unit.
As the preferable technical scheme, the metal bow tie type dipole unit, the metal square double-ring unit and the L-shaped parasitic structure are all in central symmetry with the centers of the respective substrates.
As the preferable technical scheme, a U-shaped groove is formed in the metal bow tie type dipole unit, and T-shaped gaps are formed at two sides of the U-shaped groove and used for adjusting low-frequency notch points.
As a preferable technical scheme, the metal floor is 16mm by 16mm in size; the air filling layer is positioned in the middle of the top and bottom dielectric substrates and has a thickness of 3mm; the distance between the L-shaped parasitic structure and the metal square double-ring unit is 0.15mm, so as to increase the coupling quantity; chamfering the edges of the metal bow tie type dipole units to widen the bandwidth; the dielectric substrate plate was TLY-5, had a dielectric constant of 2.2, a loss tangent of 0.0009, and a thickness of 1.52mm.
(III) beneficial effects
The invention has the beneficial effects that:
1. the invention has the outstanding characteristics of low cost, low profile, wide absorption frequency band and the like; compared with the traditional wave-absorbing material, the cross-section height of the invention is only 0.048 while the excellent wave-absorbing performance is realized; compared with the traditional structural wave absorber, the dual-polarized ultra-wide wave absorber realizes the dual-polarized ultra-wide wave absorbing frequency band (4.8 GHz-15 GHz), and also realizes the construction of dual notch frequency bands (7.2 GHz-7.6GHz and 13.1GHz-13.5 GHz) in the wave absorbing frequency band, each notch frequency band can be independently regulated by simply modifying structural parameters, the dual-polarized ultra-wide wave absorber is easy to integrate with a dual-polarized dual-frequency antenna, the radar scattering area of the antenna is reduced, and the current increasingly-improved communication requirement is met.
2. The wave absorber can achieve 4.8GHz-15GHz wave absorbing bandwidth, two notch frequency bands, namely 7.2GHz-7.6GHz and 13.1Hz-13.5GHz, are achieved through adding the square double-ring structure, the two notch frequency bands have polarization insensitivity, namely TE waves and TM waves can meet the characteristics, and independent adjustment of the notch frequency band range can be achieved through simply adjusting parameters.
Drawings
The invention may be better understood by referring to the following description in conjunction with the accompanying drawings in which like or similar reference numerals are used to indicate like or similar elements throughout the several views. The accompanying drawings, which are included to provide a further illustration of the preferred embodiments of the invention and together with a further understanding of the principles and advantages of the invention, are incorporated in and constitute a part of this specification. In the drawings:
FIG. 1 is a schematic diagram of a structural absorber unit according to the present embodiment;
FIG. 2 is a graph showing the reflection coefficient of the structure of the absorber in the pure absorption mode;
FIG. 3 (a) is a graph of reflectance for adjusting the change in TE mode high frequency notch frequency in the notch mode of the absorber of the present example structure; FIG. 3 (b) is a graph of reflectance for adjusting the change in TM mode high frequency notch frequency in the notch mode of the absorber of the present example structure;
FIG. 4 (a) is a graph showing the reflection coefficient of the notch mode of the absorber of the present example structure for adjusting the change of the TE mode low-frequency notch frequency; fig. 4 (b) is a graph showing the reflection coefficient of the TM mode high frequency notch frequency change in the notch mode of the absorber of the present example.
Description of the embodiments
For a better understanding of the present invention, reference will be made to the accompanying drawings, in which it is apparent that the embodiments described are only some, but not all embodiments of the present invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the present invention without making any inventive effort, shall fall within the scope of the present invention.
The terms first, second, third and the like in the description and in the claims and in the above drawings, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.
The following will each explain in detail by means of specific examples.
The invention provides a dual-polarized double-notch independently adjustable structural wave absorber which mainly comprises a three-layer structure, wherein the three-layer structure comprises a wave absorbing structure, an air filling layer and a notch structure from top to bottom, the wave absorbing structure is positioned at the top of the structure and comprises a medium substrate, a metal rectangular patch and a resistor which are positioned at the upper layer of the medium substrate, a metalized through hole positioned in the medium substrate, a metal bow tie type dipole unit and a resistor which are positioned at the lower layer of the medium substrate; the air filling layer is positioned in the middle of the structure and is composed of an air medium; the notch structure is positioned at the bottom of the structure and comprises a dielectric substrate, a metal square double-ring unit and an L-shaped parasitic structure which are positioned at the upper layer of the dielectric substrate, and a metal floor positioned at the lower layer of the dielectric substrate.
As shown in fig. 1, a dual-polarized dual-notch independently adjustable structural wave absorber comprises a dielectric substrate 1, which is divided into a top part and a bottom part, a metal square double-ring unit and an L-shaped parasitic structure 2 are positioned on the upper layer of the bottom dielectric substrate, a metal floor 5 is positioned on the lower layer of the bottom dielectric substrate, a metal bow-tie type dipole unit 3 is positioned on the lower layer of the top dielectric substrate and is connected with a metallized through hole 6, a metal rectangular patch 7 is positioned on the upper layer of the top dielectric substrate, and a resistor 4 is welded with the metal bow-tie type dipole unit and the metal rectangular patch.
Further, the materials adopted by the metal rectangular patch, the metal bow tie type dipole unit and the metal square double-ring unit are copper, and the thickness of the material adopted by the L-shaped parasitic structure and the metal floor is 0.035mm.
Further, the dielectric substrate 1 was made of TLY-5, and had a relative permittivity of 2.2, a loss tangent of 0.0009, and a cell size of 16mm by 1.52mm.
It should be noted that, the outer diameter of the small square metal ring of the metal square double-ring unit is FC, the FC can be 5mm-6mm, the inner diameter of the large square metal ring of the metal square double-ring unit is FB, the FB can be 6.5mm-7.5mm, the side length of the L-shaped parasitic structure close to the metal square double-ring unit is q2, and the q2 can be 0.2mm-1mm.
It should be noted that, in the metal bow tie type dipole unit 3, the length and width of the feeder line portion are 1mm x 0.8mm, the length and width of a single bow tie type metal patch is 7mm x 4.5mm, a U-shaped groove is formed in the metal bow tie type dipole unit, the width of the U-shaped groove is 0.15mm, wherein T-shaped gaps are formed on two sides of the U-shaped groove, the size of each T-shaped gap is qq, and the qq can be 5.2mm-6.1mm.
Further, the resistor 4 is in a chip resistor form, the size is 0402 packaged, and the resistance value is 110 ohms.
Further, the metal floor 5 is located at the lowest layer, and has a size of 16mm by 16mm.
Further, the metallized through holes 6 are located in the top dielectric substrate and are formed by six metal cylinders, the ground circle diameter of each metal cylinder is 0.2mm, the distance between the metal cylinders is 0.15mm, and the length is 1.52mm.
Further, the metal rectangular patch 7 is composed of two small metal rectangular patches, the length and width of each small metal rectangular patch is 1.2mm x 0.8mm, a gap is reserved between the two small metal patches, and the length of the gap is 0.6mm.
It should be noted that, simulation is performed on the optimized model, and under the condition of not adding a notch structure, the return loss is obtained as shown in fig. 2, and the wave absorption bandwidth is 4.8GHz-15GHz; after the wave absorbing structure is added, as shown in fig. 3 (a) and 3 (b), by adjusting parameters FC and q2, the high-frequency notch frequencies of the TE mode and the TM mode can be adjusted, and the low-frequency notch point is maintained unchanged; as shown in fig. 4 (a) and 4 (b), by adjusting the parameters FB and qq, the TE mode and TM mode low-frequency notch frequencies can be adjusted, and the high-frequency notch point is maintained unchanged.
The above examples are merely illustrative of the preferred embodiments of the present invention and are not intended to limit the spirit and scope of the present invention, and various modifications and improvements made by those skilled in the art to the technical solutions of the present invention should fall within the scope of protection of the present invention, and the technical content claimed by the present invention is fully described in the claims.
Claims (5)
1. A dual polarization double notch independently adjustable structural wave absorber is characterized in that: the wave absorbing structure is positioned at the top of the structure and comprises a medium substrate, a metal rectangular patch and a resistor which are positioned at the upper layer of the medium substrate, a metalized through hole positioned in the medium substrate, and a metal bow tie type dipole unit and a resistor which are positioned at the lower layer of the medium substrate; the air filling layer is positioned in the middle of the structure and is composed of an air medium; the notch structure is located at the bottom of the structure and comprises a medium substrate, a metal square double-ring unit and an L-shaped parasitic structure which are located on the upper layer of the medium substrate, and a metal floor which is located on the lower layer of the medium substrate, wherein the metal bow-tie type dipole unit is composed of four completely identical bow-tie type metal patches, a resistor is welded between the left bow-tie type metal patches and the right bow-tie type metal patches, the middle of the upper bow-tie type metal patches and the lower bow-tie type metal patches are disconnected and connected with a metallization through hole, the metallization through hole is composed of twelve metallization cylinders and symmetrically distributed and is used for connecting the metal rectangular patches on the upper layer of the top medium substrate and the metal bow-tie type metal patches on the lower layer, the metal rectangular patches are composed of two symmetrically distributed small metal rectangular patches, gaps are reserved in the middle of the metal rectangular patches and are connected with the resistor, the small metal rectangular patches are respectively connected with six metallization through holes, the metal square double-ring unit is composed of two nested metal square rings, the inner small metal square rings are used for realizing high-frequency notch points, and the outer large metal square rings are used for realizing low-frequency notch points.
2. The dual polarized double notch independently adjustable structural wave absorber of claim 1, wherein: the L-shaped parasitic structure is positioned around the metal square double-ring unit, and a high-frequency notch point is realized through coupling with the metal square double-ring unit.
3. A dual polarized dual notch independently adjustable structural wave absorber as defined in claim 2, wherein: the metal bow tie type dipole unit, the metal square double-ring unit and the L-shaped parasitic structure are all in central symmetry with the centers of the respective substrates.
4. A dual polarized dual notch independently adjustable structural wave absorber as defined in claim 3 wherein: and a U-shaped groove is formed in the metal bow tie type dipole unit, and T-shaped gaps are formed at two sides of the U-shaped groove and are used for adjusting low-frequency notch points.
5. The dual polarized double notch independently adjustable structural wave absorber of claim 1, wherein: the size of the metal floor is 16mm by 16mm; the air filling layer is positioned in the middle of the top and bottom dielectric substrates, and the thickness of the air filling layer is 3mm; the distance between the L-shaped parasitic structure and the metal square double-ring unit is 0.15mm, so as to increase the coupling amount; chamfering is carried out on the edges of the metal bow tie type dipole units so as to widen the bandwidth; the dielectric substrate plate is TLY-5, the dielectric constant is 2.2, the loss tangent is 0.0009, and the thickness is 1.52mm.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105305094A (en) * | 2014-06-30 | 2016-02-03 | 南京理工大学 | Broadside folded dipole array-based broadband microwave absorber |
| CN106785477A (en) * | 2017-03-18 | 2017-05-31 | 电子科技大学 | A kind of double-frequency broadband wave absorbing device |
| KR102129386B1 (en) * | 2019-09-16 | 2020-07-02 | 충북대학교 산학협력단 | Ultrawide Bandwidth Electromagnetic Wave Absorbers Using High-Capacitive Spiral Frequency Selective Surfaces |
| CN112928491A (en) * | 2021-01-13 | 2021-06-08 | 电子科技大学 | Ultra-wideband wave-absorbing dual-polarized switchable anti-absorption integrated material |
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2022
- 2022-03-11 CN CN202210242359.4A patent/CN114976673B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105305094A (en) * | 2014-06-30 | 2016-02-03 | 南京理工大学 | Broadside folded dipole array-based broadband microwave absorber |
| CN106785477A (en) * | 2017-03-18 | 2017-05-31 | 电子科技大学 | A kind of double-frequency broadband wave absorbing device |
| KR102129386B1 (en) * | 2019-09-16 | 2020-07-02 | 충북대학교 산학협력단 | Ultrawide Bandwidth Electromagnetic Wave Absorbers Using High-Capacitive Spiral Frequency Selective Surfaces |
| CN112928491A (en) * | 2021-01-13 | 2021-06-08 | 电子科技大学 | Ultra-wideband wave-absorbing dual-polarized switchable anti-absorption integrated material |
Non-Patent Citations (1)
| Title |
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| 基于新型电磁人工材料的吸波材料双极化双频带研究;张鹏程;林先其;沈睿;;新型工业化(第03期);全文 * |
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