Low-scattering antenna array plane based on artificial magnetic conductor structure

Abstract

The invention relates to the technical field of antennas and electromagnetic stealth, and particularly discloses a low-scattering antenna array plane based on an artificial magnetic conductor structure, which comprises an upper dielectric layer, an air layer and a lower dielectric layer which are sequentially arranged from top to bottom, a plurality of groups of patch units A and a plurality of groups of patch units B are arranged on the upper surface of the upper dielectric layer in an array staggered manner; each group of patch units A comprises a plurality of groups of slotted kerf patches which are periodically arranged and are provided with kerfs; each group of patch units B comprises a plurality of groups of common patches which are periodically arranged; an upper micro-strip feeder line is arranged on the upper surface of the lower dielectric layer; the lower surface of the lower dielectric layer is provided with a metal floor, and the metal floor is provided with a lower strip-shaped gap corresponding to the upper micro-strip feeder line and a coaxial cable connected with the upper micro-strip feeder line. The radiation and scattering integrated antenna array plane with broadband radiation performance and broadband low scattering performance is realized through a mechanism that the artificial magnetic conductor orthogonal reflecting screen performs interference cancellation by using a reflected wave phase difference.

Description

Technical Field

[0001] The present invention relates to the technical field of antenna and electromagnetic stealth, and more specifically, to a low-scattering antenna array based on an artificial magnetic conductor structure. Background Art

[0002] With the continuous development of radar wireless detection technology, the demand for broadband scattering reduction performance of stealth antennas is also increasing; this requires that the antenna has broadband radiation performance and the ability to reduce the radar cross section (RCS) within a wider frequency band to ensure the low detectability of one's own aircraft.

[0003] At present, antenna scattering reduction technologies include traditional shaping technology, applying absorbing materials, and using metasurface structures for scattering cancellation and diffuse reflection. Common metasurface structures used for scattering reduction include artificial magnetic conductors, electromagnetic bandgap structures, polarization rotation surfaces, etc.

[0004] However, the metasurface structure is only placed around the antenna as an additional structure, which has a large physical area as a whole and may deteriorate the radiation performance of the antenna. In existing work, it is rare to have an antenna array that has both good radiation performance and low scattering performance without introducing additional structures. Therefore, the development of low-scattering antenna arrays that have both radiation functions and electromagnetic stealth characteristics is particularly important to meet the increasingly stringent high bandwidth and low detectability in engineering. Summary of the invention

[0005] The technical problem to be solved by the present invention is to provide a low-scattering antenna array based on an artificial magnetic conductor structure;

[0006] The solution adopted by the present invention to solve the technical problem is:

[0007] A low-scattering antenna array based on an artificial magnetic conductor structure, comprising an upper dielectric layer, an air layer and a lower dielectric layer arranged in sequence from top to bottom;

[0008] On the upper surface of the upper dielectric layer, a plurality of groups of patch units A and a plurality of groups of patch units B are arranged in an array and staggered;

[0009] Each group of patch units A includes a plurality of groups of slotted and slit patches that are periodically arranged and have slits; each group of patch units B includes a plurality of groups of ordinary patches that are periodically arranged;

[0010] An upper microstrip feed line corresponding to the slotted and slit patches and the common patches is arranged on the upper surface of the lower dielectric layer;

[0011] A metal floor is arranged on the lower surface of the lower dielectric layer, and a lower strip-shaped gap corresponding to the upper microstrip feeder line and a coaxial cable connected to the upper microstrip feeder line are arranged on the metal floor.

[0012] In some possible implementations, the slotted patch is provided with two groups of first slits located on the same straight line, and slit units that are provided on the straight line where the two groups of first slits are located and are symmetrically arranged.

[0013] The two groups of the first slits are close to each other at one end to form a gap; the other ends of the two groups of the first slits extend to two opposite end surfaces of the slotted patch.

[0014] In some possible embodiments, the gap unit includes a second gap and a gap group arranged on the side of the second gap away from the first gap; the first gap, the second gap, and the gap group are arranged at equal intervals; and both ends of the second gap pass through two opposite end surfaces of the slotted patch.

[0015] In some possible implementations, the slit group includes a third slit disposed on a side of the second slit away from the first slit, and a fourth slit disposed on a side of the third slit away from the second slit;

[0016] The first gap, the second gap, the third gap, and the third gap are arranged at equal intervals and the gap is B; the length of the second gap is a, the length of the third gap is b, and the length of the third gap is c, a>b>c;

[0017] The midpoints of the straight lines where the two groups of first gaps are located, the midpoints of the second gaps, the midpoints of the third gaps, and the midpoints of the third gaps are on the same straight line.

[0018] In some possible implementations, the gap A between the two groups of the first gaps is: A=5.9 mm±0.1 mm; B=4.6 mm±0.1 mm.

[0019] In some possible implementations, each group of the slotted and slit patches in the patch unit A is four groups, and the four groups of slotted and slit patches are distributed in two rows and two columns; the patch unit B is four groups of ordinary patches, and the four groups of ordinary patches are distributed in two rows and two columns.

[0020] In some possible implementations, the widths of the first gap, the second gap, the third gap and the fourth gap are all 1 mm, and the lengths of the first gap, the second gap, the third gap and the fourth gap are 15 mm, 36 mm, 19 mm and 17 mm respectively.

[0021] In some possible implementations, the slotted and slit patch and the common patch are both square structures, and the slotted and slit patch and the common patch are the same in size, and the side lengths of both are 38 mm;

[0022] The upper dielectric layer, the air layer and the lower dielectric layer are all of square structure, and the side lengths of the upper dielectric layer, the air layer and the lower dielectric layer are all 240 m.

[0023] In some possible implementations, the length of the upper microstrip feed line is 26.5 mm and the width is 4 mm; the length of the lower strip-shaped gap is 47 mm and the width is 0.5 mm;

[0024] The thickness of the upper dielectric layer is 2 mm, the thickness of the air layer is 7 mm, and the thickness of the lower dielectric layer is 5 mm.

[0025] In some possible implementations, the upper microstrip feed line is connected to the coaxial cable through a metallized via; and the material of the upper dielectric layer and the lower dielectric layer is RT / duroi d5880.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention utilizes two slotted patches and common patches with the same shape and size but different structures as radiation units, and the radiation characteristics thereof are similar but the reflection phases of electromagnetic waves are different;

[0028] The present invention realizes the radiation and scattering integrated antenna array with broadband radiation performance and broadband low scattering performance by using the mechanism of interference cancellation of reflected wave phase difference through an artificial magnetic conductor orthogonal reflection screen;

[0029] The present invention has the advantages of low profile, simple structure and strong robustness. Without introducing additional scattering reduction structure, it realizes an antenna array with low scattering characteristics, with an impedance bandwidth of 2-2.5GHz and a radar scattering cross-section reduction bandwidth of 8dB of 2-4GHz. When the installation space is limited, it can provide a better solution for stealth antennas. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0031] Figure 2 is a schematic structural diagram of the lower dielectric layer in the present invention;

[0032] Figure 3 It is a structural schematic diagram of the upper surface of the lower dielectric layer in the present invention;

[0033] Figure 4 It is a structural schematic diagram of the lower surface of the lower dielectric layer in the present invention;

[0034] Figure 5 It is a schematic diagram of the structure of the slotted and slit patch in the present invention;

[0035] Figure 6 It is the S(1,1) curve diagram of the present invention;

[0036] Figure 7 is an RCS reduction curve diagram of the present invention;

[0037] in:

[0038] 1. Upper dielectric layer;

[0039] 11. Slotting and cutting patches;

[0040] 111. The first gap;

[0041] 112. The second gap;

[0042] 113. The third gap;

[0043] 114. The fourth gap;

[0044] 12. Ordinary patch;

[0045] 2. Air layer;

[0046] 3. Lower dielectric layer;

[0047] 31. Upper microstrip feed line;

[0048] 32. Metal floor;

[0049] 33. Lower strip gap;

[0050] 4. Coaxial cable. DETAILED DESCRIPTION

[0051] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral body; it can be directly connected, or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. The "first", "second" and similar words mentioned in this application do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, "one" or "one" and other similar words do not indicate a quantity restriction, but indicate the existence of at least one. In the implementation of this application, "and / or" describes the association relationship of the associated objects, indicating that there can be three relationships, for example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In the description of the embodiments of the present application, unless otherwise specified, the meaning of "multiple" refers to two or more. For example, multiple positioning columns refer to two or more positioning columns. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] The present invention is described in detail below.

[0053] like Figure 1-Figure 5 As shown:

[0054] A low-scattering antenna array based on an artificial magnetic conductor structure comprises an upper dielectric layer 1, an air layer 2 and a lower dielectric layer 3 which are stacked in sequence from top to bottom;

[0055] On the upper surface of the upper dielectric layer 1, a plurality of groups of patch units A and a plurality of groups of patch units are arranged in an array in an interlaced manner; that is, the distribution of the plurality of groups of patch units A and the plurality of groups of patch units B is similar to the distribution of black and white squares on a chess board; the patch units A and the patch units are distributed in an interlaced manner;

[0056] Each group of patch units A includes a plurality of groups of slotted and slit patches 11 which are periodically arranged and have slits; each group of patch units B includes a plurality of groups of ordinary patches 12 which are periodically arranged;

[0057] The slotted patch 11 and the common patch 12 have the same shape and size, which may be round or square. The slotted patch 11 and the common patch 12 are made of the same material as the antenna array surface in the prior art, and will not be described in detail here.

[0058] An upper microstrip feed line 31 corresponding to the slotted patch 11 and the common patch 12 is provided on the upper surface of the lower dielectric layer 3;

[0059] A metal floor 32 is provided on the lower surface of the lower dielectric layer 3, and a lower strip gap 33 corresponding to the upper microstrip feeder line 31 and a coaxial cable 4 connected to the upper microstrip feeder line 31 are provided on the metal floor 32; specifically, the upper microstrip feeder line 31 is connected to the coaxial cable 4 provided on the metal floor 32 through a metallized via; the standard load of the coaxial cable 4 is preferably 50 ohms.

[0060] The air layer 2 is used for impedance matching of antenna coupling feeding, and the material of the upper dielectric layer 1 and the lower dielectric layer 3 is preferably RT / duro i d5880 high frequency board;

[0061] The slotted patch 11 and the common patch 12 are used as two artificial magnetic conductor units at the same time; the orthogonal reflection screen of the artificial magnetic conductor unit utilizes the interference cancellation mechanism of the reflected wave phase difference to realize the radiation and scattering integrated antenna array with broadband radiation performance and broadband low scattering performance;

[0062] The slotted and slit patch 11 is slotted and slitted so that the upper surface of the slotted and slit patch 11 has slits. While the radiation performance of the square microstrip antenna is not changed, the structural change makes it have a reflected beam phase difference of nearly 180° compared with the original structure, thereby forming artificial magnetic conductor characteristics for scattering cancellation.

[0063] The upper microstrip feed line 31 is used for impedance matching and coupled feeding, and stimulates the slotted patch 11 and the common patch 12 on the upper surface of the upper dielectric layer 1, so as to independently adjust the radiation performance of the antenna;

[0064] In some possible implementations, the slotted patch 11 is provided with two groups of first slits 111 located on the same straight line, and slit units that are provided on the straight line where the two groups of first slits 111 are located and are symmetrically arranged.

[0065] The two groups of the first slits 111 are close to each other at one end to form a gap; the other ends of the two groups of the first slits 111 extend to two opposite end surfaces of the slotted patch 11.

[0066] In some possible embodiments, the gap unit includes a second gap 112 and a gap group arranged on the side of the second gap 112 away from the first gap 111; the first gap 111, the second gap 112, and the gap group are arranged at equal intervals; the two ends of the second gap 112 pass through the two opposite end faces of the slotted patch 11.

[0067] In some possible implementations, the slit group includes a third slit 113 disposed on a side of the second slit 112 away from the first slit 111, and a fourth slit 114 disposed on a side of the third slit 113 away from the second slit 112;

[0068] The first slit 111, the second slit 112, the third slit 113, and the third slit 113 are arranged at equal intervals and the interval is B; the length of the second slit 112 is a, the length of the third slit 113 is b, and the length of the third slit 113 is c, a>b>c;

[0069] The midpoints of the straight lines where the two groups of first slits 111 are located, the midpoints of the second slits 112 , and the midpoints of the third slits 113 are located on the same straight line.

[0070] In some possible implementations, the gap A between the two groups of the first gaps 111 is A=5.9 mm±0.1 mm; B=4.6 mm±0.1 mm.

[0071] In some possible implementations, each group of the slotted and slit patches 11 in the patch unit A is four groups, and the four groups of slotted and slit patches 11 are distributed in two rows and two columns; the patch unit B is four groups of ordinary patches 12, and the four groups of ordinary patches 12 are distributed in two rows and two columns.

[0072] In some possible implementations, the widths of the first gap 111, the second gap 112, the third gap 113 and the fourth gap 114 are all 1 mm, and the lengths of the first gap 111, the second gap 112, the third gap 113 and the fourth gap 114 are 15 mm, 36 mm, 19 mm and 17 mm respectively.

[0073] In some possible implementations, the slotted and slit patch 11 and the common patch 12 are both square structures, and the slotted and slit patch 11 and the common patch 12 have the same size, and the side lengths of both are 38 mm;

[0074] The upper dielectric layer 1, the air layer 2 and the lower dielectric layer 3 are all square structures, and the side lengths of the upper dielectric layer 1, the air layer 2 and the lower dielectric layer 3 are all 240 m.

[0075] In some possible implementations, the length of the upper microstrip feed line 31 is 26.5 mm and the width is 4 mm; the length of the lower strip-shaped gap 33 is 47 mm and the width is 0.5 mm;

[0076] In some possible implementations, the total thickness of the antenna array surface is 14 mm, the thickness of the upper dielectric layer 1 is 2 mm, the thickness of the air layer 2 is 7 mm, and the thickness of the lower dielectric layer 3 is 5 mm.

[0077] Embodiment 1:

[0078] The present embodiment provides a low-scattering antenna array based on an artificial magnetic conductor structure, based on the above structure; specifically, the gap A between the two groups of the first gaps 111, A=5.9m; the first gap 111, the second gap 112, the third gap 113, and the third gap 113 are arranged at equal intervals and the gap is B; B=4.6mm; the total thickness of the antenna array is 14mm, the thickness of the upper dielectric layer 1 is 2mm, the thickness of the air layer 2 is 7mm, and the thickness of the lower dielectric layer 3 is 5mm; the length of the upper microstrip feed line 31 is 26.5mm and the width is 4mm; the length of the lower strip gap 33 is 47mm and the width is 0.5mm; the upper dielectric layer 1, the air layer 2 and the lower dielectric layer 3 are all square structures, and the upper dielectric layer 1 is 2mm thick, the air layer 2 is 7mm thick, and the lower dielectric layer 3 is 5mm thick; The side lengths of the material layer 1, the air layer 2 and the lower dielectric layer 3 are all 240m; there are four groups of slotted and slit patches 11 in each group of the patch unit A, and the four groups of slotted and slit patches 11 are distributed in two rows and two columns; there are four groups of ordinary patches 12 in the patch unit B, and the four groups of ordinary patches 12 are distributed in two rows and two columns; the slotted and slit patches 11 and the ordinary patches 12 are both square structures, and the slotted and slit patches 11 and the ordinary patches 12 have the same size and the side lengths are both 38mm; the widths of the first gap 111, the second gap 112, the third gap 113 and the fourth gap 114 are all 1mm, and the lengths of the first gap 111, the second gap 112, the third gap 113 and the fourth gap 114 are respectively 15mm, 36mm, 19mm, and 17mm. The material of the upper dielectric layer 1 and the lower dielectric layer 3 is preferably RT / duroi d5880 high frequency board; the standard load of the coaxial cable 4 is 50 ohms.

[0079] The present invention starts with a traditional rectangular microstrip antenna and improves it to broaden the impedance bandwidth of the microstrip antenna; the mechanism of interference cancellation of orthogonal reflection screens of artificial magnetic conductors is applied thereto, thereby realizing the design of a low-scattering antenna array with both radiation characteristics and electromagnetic stealth characteristics.

[0080] The present invention utilizes two patches of the same size and different structural forms as radiation units, which have similar radiation characteristics but different electromagnetic wave reflection phases; through the artificial magnetic conductor orthogonal reflection screen, the reflected wave phase difference is used to perform interference cancellation, thereby realizing a radiation and scattering integrated antenna array with broadband radiation performance and broadband low scattering performance.

[0081] In terms of the radiation performance of the antenna, the present invention increases and lengthens the path of the induced current on the antenna surface by introducing the slotted and slit patch 11, thereby improving the impedance bandwidth of the antenna.

[0082] In terms of the scattering performance of the antenna, the slotted patch 11 is introduced to make the patch antenna unit have a reflection phase difference of about 180° within a wide frequency band for the incident electromagnetic wave compared to the ordinary patch antenna unit without slots. The arrangement combination of the slotted patch 11 and the ordinary patch 12 can make the scattered wave beam be offset in reverse phase, thereby achieving single-station RCS reduction without introducing additional stealth structure.

[0083] The slot structure (first slot 111, second slot 112, third slot 113 and fourth slot 114) in the slotted patch 11 is symmetrical in the upper half plane and the lower half plane, and the left half plane and the right half plane are also symmetrical with each other. Therefore, the slot structure has polarization insensitivity and can achieve RCS reduction and antenna electromagnetic stealth under the incidence of electromagnetic waves with different polarizations.

[0084] The present invention has the advantages of low profile, simple structure and strong robustness, and realizes the antenna array design with low scattering characteristics without introducing additional scattering reduction structure.

[0085] like Figure 6 and Figure 7 As shown, by simulating Example 1, it is found that the impedance bandwidth is 2-2.5 GHz, and the radar scattering cross section reduction bandwidth is 8 dB 2-4 GHz. It can be seen that the present invention is expected to become a good stealth antenna solution with limited installation space.

[0086] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A low-scattering antenna array based on an artificial magnetic conductor structure, characterized in that: It includes an upper dielectric layer, an air layer and a lower dielectric layer arranged in sequence from top to bottom; On the upper surface of the upper dielectric layer, a plurality of groups of patch units A and a plurality of groups of patch units B are arranged in an array and staggered; Each group of patch units A includes a plurality of groups of slotted and slit patches that are periodically arranged and have slits; each group of patch units B includes a plurality of groups of ordinary patches that are periodically arranged; An upper microstrip feed line corresponding to the slotted and slit patches and the common patches is arranged on the upper surface of the lower dielectric layer; A metal floor is arranged on the lower surface of the lower dielectric layer, and a lower strip-shaped gap corresponding to the upper microstrip feeder line and a coaxial cable connected to the upper microstrip feeder line are arranged on the metal floor.

2. The low-scattering antenna array based on an artificial magnetic conductor structure according to claim 1, characterized in that: The slotted patch is provided with two groups of first slots located on the same straight line, and slot units that are arranged symmetrically on the straight line where the two groups of first slots are located; The two groups of the first slits are close to each other at one end to form a gap; the other ends of the two groups of the first slits extend to two opposite end surfaces of the slotted patch.

3. The low-scattering antenna array based on an artificial magnetic conductor structure according to claim 2, characterized in that: The slot unit comprises a second slot and a slot group arranged at a side of the second slot away from the first slot; the first slot, the second slot and the slot group are arranged at equal intervals; and both ends of the second slot penetrate two opposite end surfaces of the slotted patch.

4. The low-scattering antenna array based on an artificial magnetic conductor structure according to claim 3, characterized in that: The slit group includes a third slit arranged on a side of the second slit away from the first slit, and a fourth slit arranged on a side of the third slit away from the second slit; The first gap, the second gap, the third gap, and the third gap are arranged at equal intervals and the gap is B; the length of the second gap is a, the length of the third gap is b, and the length of the third gap is c, a>b>c; The midpoints of the straight lines where the two groups of first gaps are located, the midpoints of the second gaps, the midpoints of the third gaps, and the midpoints of the third gaps are on the same straight line.

5. The low-scattering antenna array based on an artificial magnetic conductor structure according to claim 4, characterized in that: The gap A between the two groups of the first gaps is A=5.9 mm±0.1 mm; B=4.6 mm±0.1 mm.

6. The low-scattering antenna array based on an artificial magnetic conductor structure according to claim 4, characterized in that: There are four groups of slotted and slit patches in each group of patch units A, and the four groups of slotted and slit patches are distributed in two rows and two columns; there are four groups of ordinary patches in the patch unit B, and the four groups of ordinary patches are distributed in two rows and two columns.

7. The low-scattering antenna array based on an artificial magnetic conductor structure according to claim 4, characterized in that: The widths of the first gap, the second gap, the third gap and the fourth gap are all 1 mm, and the lengths of the first gap, the second gap, the third gap and the fourth gap are 15 mm, 36 mm, 19 mm and 17 mm respectively.

8. A low-scattering antenna array based on an artificial magnetic conductor structure according to any one of claims 1 to 7, characterized in that: The slotted and slit patch and the ordinary patch are both square in structure, and the slotted and slit patch and the ordinary patch are the same in size, and the side length is 38 mm; The upper dielectric layer, the air layer and the lower dielectric layer are all of square structure, and the side lengths of the upper dielectric layer, the air layer and the lower dielectric layer are all 240 m.

9. A low-scattering antenna array based on an artificial magnetic conductor structure according to any one of claims 1 to 7, characterized in that: The length of the upper microstrip feed line is 26.5 mm and the width is 4 mm; the length of the lower strip-shaped gap is 47 mm and the width is 0.5 mm; The thickness of the upper dielectric layer is 2 mm, the thickness of the air layer is 7 mm, and the thickness of the lower dielectric layer is 5 mm.

10. A low-scattering antenna array based on an artificial magnetic conductor structure according to any one of claims 1 to 7, characterized in that: The upper microstrip feed line is connected to the coaxial cable through a metallized via; the material of the upper dielectric layer and the lower dielectric layer is RT / duroid5880.

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