Double-layer all-metal dual-band transmission array antenna

Abstract

According to the double-layer all-metal dual-band transmission array antenna, compared with a traditional metasurface, an all-metal structure is adopted, a dielectric substrate structure is removed, the antenna adopting the all-metal structure is not prone to being affected by the environment temperature and is more difficult to be broken down by high-power wave beams, and compared with an existing double-layer all-metal transmission array antenna, the double-layer all-metal dual-band transmission array antenna has the advantages that the structure is simple, and the cost is low. Under the conditions that a high transmission coefficient and a 360-degree phase compensation range are achieved at the same time, metal connecting columns do not need to be added, the machining process of the array is simplified, transmission electromagnetic waves cannot be subjected to polarization rotation, and the universality of the double-layer all-metal unit is greatly widened. And compared with a Huygens unit, the design is simpler and more convenient in design difficulty. And the design realizes the double-frequency working capability under a double-layer all-metal structure for the first time.

Description

Technical Field

[0001] The utility model belongs to the technical field of super surface antennas, in particular to a double-layer all-metal dual-band transmission array antenna. Background Art

[0002] As a new generation of high-gain antennas, metasurfaces combine the advantages of optical lens principles and array antennas and have been widely studied. Compared with reflective array antennas, transmission array antennas have been studied more deeply because they eliminate feeding obstacles. So far, dual-band antennas, multi-beam antennas, orbital angular momentum antennas, reconfigurable antennas and other fields have been widely studied. The units in these antenna structures are usually composed of a dielectric substrate and a metal patch structure.

[0003] Since most metasurface components have dielectric layers, the extreme temperature conditions in the space environment and the temperature changes caused by the heat generated by dielectric loss when facing high-power beams will cause changes in the dielectric constant of the material, thereby affecting the performance of the antenna. In order to overcome these shortcomings, all-metal metasurfaces have received widespread attention.

[0004] The all-metal transmission array antenna eliminates the expensive dielectric substrate of the antenna, removes the restrictions on the use environment, and when the antenna array surface is large, the all-metal structure will greatly reduce the production cost of the antenna. It only needs to be laser engraved, which greatly simplifies the processing complexity.

[0005] In recent years, people have conducted relevant research on all-metal transmission array antennas. It is generally believed that at least three metal layers are required to enable the unit to achieve a 360-degree transmission phase shift of electromagnetic waves. Therefore, in order to obtain a better transmission coefficient and phase range, people generally use a unit structure of multi-layer metal plates. However, the multi-layer all-metal transmission array has a complex structure, a difficult manufacturing process, and high cost.

[0006] Therefore, the design of all-metal transmission arrays that reduce the number of layers to two or less has been widely studied. And how to make the unit still have a high transmission coefficient and a 360-degree phase compensation range under this structure is an urgent problem to be solved. At present, one of the design methods of double-layer pure metal elements is a double-layer pure metal transmission array antenna with polarization rotation function disclosed in the patent document with Chinese patent publication number CN112421227A. The transmission unit includes an upper metal layer, a lower metal layer and a metal column; the upper metal layer and the lower metal layer have two U-shaped gaps of different lengths and the U-shaped gaps are orthogonally distributed; the metal column connects the upper metal layer and the lower metal layer. Relying on the metal column, the unit has a good transmission coefficient and a 360-degree phase compensation range. There is also a transmission array and antenna based on an all-metal Huygens metasurface disclosed in the patent document with Chinese patent publication number CN115207638A, in which the transmission array unit is composed of all-metal multi-slot gaps, which realizes 360-degree transmission phase control while keeping the transmission amplitude higher than -2dB. There is also a low-profile double-layer all-metal transmission array antenna disclosed in the patent document with Chinese patent publication number CN218385764U, in which the transmission array unit includes an upper metal plate and a lower metal plate, and a double C-shaped slot is etched on the metal plate. The double C-shaped slot structure of the lower layer is obtained by rotating ±90 degrees on the basis of the double C-shaped slot of the upper layer. The double C-shaped slot structure of the lower layer is rotated 90 degrees counterclockwise on the basis of the C-shaped slot of the upper layer to obtain state A, which can achieve a phase range of about 180 degrees; rotate 90 degrees clockwise to obtain state B, which is 180 degrees different from state A in phase, so a total phase shift range of 360 degrees can be obtained.

[0007] However, in the above-mentioned units, the use of metal columns for connection will not only increase the difficulty of antenna manufacturing, but also bring more insertion loss. The units designed using the Huygens principle require a large number of parameter scans on three parameters to build a database that meets the performance requirements. This design process is complex and time-consuming. The units that rely on the C-shaped slot structure will cause the electromagnetic waves to undergo unavoidable polarization rotation. And the above-mentioned existing units are difficult to achieve the function of dual-frequency operation. Utility Model Content

[0008] The utility model provides a double-layer all-metal dual-band transmission array antenna, which solves the problem of complicated design process of the all-metal transmission array when the number of layers is reduced to two layers or less.

[0009] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0010] A double-layer all-metal dual-band transmission array antenna comprises a pyramidal horn antenna and a transmission array, wherein the pyramidal horn antenna is a feed source of the transmission array, wherein the transmission array comprises two layers of metal plates, an air layer is arranged between the two layers of the metal plates, and each of the metal plates is provided with a plurality of transmission units, wherein the transmission units are provided with a first I-shaped slot structure and a third I-shaped slot structure of two groups of different lengths parallel to the x-direction and a second I-shaped slot structure and a fourth I-shaped slot structure of two groups of different lengths parallel to the y-direction.

[0011] Preferably, the second I-shaped slit structure and the fourth I-shaped slit structure are both periodically arranged on the transmission unit, with a period of P in the y direction and a period of P / 2 in the x direction.

[0012] Preferably, the first I-shaped slit structure and the third I-shaped slit structure are both periodically arranged on the transmission unit, with a period of P / 2 in the y direction and a period of P in the x direction.

[0013] Preferably, the geometric centers of the second I-shaped gap structure and the fourth I-shaped gap structure are P / 4 apart in the x direction and P / 2 apart in the x direction.

[0014] Preferably, the geometric centers of the first I-shaped gap structure and the third I-shaped gap structure are P / 2 apart in the x direction and P / 4 apart in the x direction.

[0015] Preferably, the two metal plates are both square structures and have the same size.

[0016] Preferably, the size of the metal plate is 480 mm×480 mm.

[0017] Preferably, the transmission units are periodically arranged on the metal plate.

[0018] Preferably, the spacing between the transmission units is 30 mm.

[0019] Preferably, the first I-shaped slot structure, the third I-shaped slot structure, the second I-shaped slot structure and the fourth I-shaped slot structure have the same slot width.

[0020] Compared with the prior art, the utility model has the following beneficial effects: This patent provides a double-layer all-metal dual-band transmission array antenna, which adopts an all-metal structure and removes the dielectric substrate structure compared to the traditional metasurface. The dielectric constant of the dielectric substrate is easily affected by the ambient temperature, so the temperature changes in some extreme environments such as the space environment will make the performance of the traditional metasurface unstable or even unable to work. And when facing high-power beams, the large amount of heat generated by the dielectric loss of the dielectric substrate will easily break down the unit. The antenna with an all-metal structure is not easily affected by the ambient temperature and is more difficult to be broken down by high-power beams. Compared with the existing double-layer all-metal transmission array antenna, under the condition of having a high transmission coefficient and a phase compensation range of 360 degrees, this design first does not require the addition of metal connecting columns, which simplifies the processing process of the array and does not cause the polarization rotation of the transmitted electromagnetic wave, which greatly broadens the universality of the double-layer all-metal unit. Moreover, compared with the Huygens unit, this design is simpler and more convenient in terms of design difficulty. And this design realizes the dual-frequency working capability under the double-layer all-metal structure for the first time. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of a double-layer all-metal dual-band transmission array antenna of the utility model operating at 6.5 GHz.

[0022] Figure 2 This is a schematic diagram of a double-layer all-metal dual-band transmission array antenna of the utility model operating at 9.5 GHz.

[0023] Figure 3 This is a double-layer all-metal dual-band transmission array antenna of the utility model, wherein a is an enlarged view of the array surface structure and b is a schematic diagram of the basic unit structure.

[0024] Figure 4 It is a three-dimensional schematic diagram of a transmission unit of a double-layer all-metal dual-band transmission array antenna of the utility model.

[0025] Figure 5 This is a curve diagram of the transmission coefficient and phase shift of a transmission unit of a double-layer all-metal dual-band transmission array antenna of the utility model, which varies with L11 and L1 at design frequencies of 6.3 GHz, 6.5 GHz and 6.7 GHz.

[0026] Figure 6 The utility model is a transmission unit of a double-layer all-metal dual-band transmission array antenna, and is a curve diagram showing the transmission coefficient and phase shift as L33 changes at design frequencies of 9.3 GHz, 9.5 GHz and 9.7 GHz.

[0027] Figure 7The utility model discloses a double-layer all-metal dual-band transmission array antenna, and provides measured and simulated normalized radiation patterns of the E-plane at 6.3 GHz, 6.5 GHz and 6.7 GHz.

[0028] Figure 8 The utility model discloses a double-layer all-metal dual-band transmission array antenna, and provides measured and simulated normalized radiation patterns of the E-plane at 9.3 GHz, 9.5 GHz and 9.7 GHz.

[0029] Fig. 9 This is a curve diagram of the gain and aperture efficiency of a double-layer all-metal dual-band transmission array antenna of the utility model, which is simulated and measured at 6.5GHz and changes with frequency.

[0030] Fig.10 This is a curve diagram of the gain and aperture efficiency of a double-layer all-metal dual-band transmission array antenna of the utility model, which is simulated and measured at 9.5GHz and changes with frequency.

[0031] Fig.11 It is a schematic diagram of the I-type structure arrangement in the embodiment;

[0032] In the figure: 1. pyramidal horn antenna; 2. second pyramidal horn antenna; 3. transmission array; 4. transmission unit; 5. metal plate; 6. first I-shaped slot structure; 7. second I-shaped slot structure; 8. third I-shaped slot structure; 9. fourth I-shaped slot structure. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.

[0034] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] In the description of the embodiments of the present utility model, it should be noted that if the terms "upper", "lower", "horizontal", "inner", etc. indicate an orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the utility model product is usually placed when in use, it is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.

[0037] In addition, if the term "horizontal" appears, it does not mean that the component must be absolutely horizontal, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", which does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0038] In the description of the embodiments of the present utility model, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0039] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below in conjunction with the accompanying drawings.

[0040] like Figure 1 The utility model provides a double-layer all-metal dual-band transmission array antenna, including a pyramid horn antenna and a transmission array, wherein the pyramid horn antenna 1 is a feed source of the transmission array 3, and the transmission array 3 includes two layers of metal plates 5, an air layer is arranged between the two layers of the metal plates 5, and each of the metal plates 5 is provided with a plurality of transmission units 4.

[0041] The thickness of the metal plate is d=1 mm, and the thickness of the air layer is h=8 mm. The transmission array is composed of transmission units arranged periodically, and the spacing between the transmission units is P=30 mm.

[0042] The transmission unit 4 is provided with two groups of first I-shaped slot structures 6 and third I-shaped slot structures 8 with different lengths parallel to the x direction and two groups of second I-shaped slot structures 7 and fourth I-shaped slot structures 9 with different lengths parallel to the y direction. The second I-shaped slot structures 7 and the third I-shaped slot structures 9 are periodically arranged on the transmission unit 4, with a period of P in the y direction and a period of P / 2 in the x direction. The first I-shaped slot structures 6 and the third I-shaped slot structures 8 are periodically arranged on the transmission unit 4, with a period of The period is P / 2, the period in the x direction is P, the geometric centers of the second I-shaped slit structure 7 and the fourth I-shaped slit structure 9 are P / 4 apart in the x direction and P / 2 apart in the x direction, the geometric centers of the first I-shaped slit structure 6 and the third I-shaped slit structure 8 are P / 2 apart in the x direction and P / 4 apart in the x direction, the first I-shaped slit structure 6, the third I-shaped slit structure 8, the second I-shaped slit structure 7 and the fourth I-shaped slit structure 9 have the same slit width, and the width of all the I-shaped slits is W. And the length is adjustable for linearly adjusting the transmission performance of the unit, for specific positional relationships, see Fig.11 , the dotted box is a transmission unit 4, two I-shaped slots are arranged in the same direction, blue and green correspond to the second I-shaped slot structure 7 and the fourth I-shaped slot structure 9, the two structures work together at the first frequency 6.5GHz, all blue structures have a period of P / 2 in the x direction and a period of P in the y direction, all green structures have a period of P / 2 in the x direction and a period of P in the y direction. The blue structure is a complete structure in the center of the transmission unit 4, with half on each side. The distance between green and blue in the x direction is P / 4.

[0043] exist Figure 4 In the figure, the first I-shaped slot structure 6 and the third I-shaped slot structure 8 parallel to the x-direction work at a first frequency of 9.5 GHz, and can regulate electromagnetic waves with polarization direction in the y-direction. The second I-shaped slot structure 7 and the fourth I-shaped slot structure 9 parallel to the x-direction work at a second frequency of 6.5 GHz, and can regulate electromagnetic waves with polarization direction in the x-direction. The orthogonal arrangement of the two structures working at different frequencies can minimize the coupling between the structures due to cross-coupling, so that the array has the function of dual-frequency operation.

[0044] The vertical distance between the phase center of the pyramid horn antenna and the transmission array is 514.7 mm. The aperture size of the transmission array 3 is 480 mm × 480 mm, including 256 transmission units;

[0045] When working at 6.5GHz, the main length L1 of the second I-shaped slot structure 7 varies in the range of 23mm-26mm, and the range of L11 varies in the range of 2mm-5mm. The main length L2 of the fourth I-shaped slot structure 9 varies in two states. When L11=2mm, L2=0.67×L1+4.67mm, where L1 varies in the range of 23mm-26mm; when L1=26mm, L2=0.67×L11+20.67mm, where L11 varies in the range of 2mm-5mm. Figure 5 , the performance of the unit operating at 6.5GHz and nearby is given. By continuously adjusting the lengths of L1 and L11, a continuously changing phase compensation can be obtained, which enables the unit to have a higher transmission coefficient>-2dB and a phase shift compensation range of 360 degrees.

[0046] When working at 9.5GHz, the main length L1 of the second I-shaped slot structure 7 varies from 23mm to 26mm, and the length L11 varies from 2mm to 5mm. The length L33 of the branches at both ends of the first I-shaped slot structure 6 varies from 7mm to 11mm, and the length L44 of the branches at both ends of the fourth I-shaped slot structure 9 is equal to 0.625×L33+0.125mm. Figure 6 , the performance of the unit operating at 9.5GHz and nearby is given. Similarly, by continuously adjusting the length of L33, the unit has a higher transmission coefficient>-2dB and a phase shift compensation range of 360 degrees.

[0047] The other parameters are L2=20mm, L3=11mm, L4=11mm.

[0048] Reference Fig.11 , the green structure changes in length with the blue structure at a certain ratio, but the blue structure starts from a state without horizontal branches at both ends and then the branches at both ends begin to grow longer after the trunk reaches a certain length, so there are two changing functions. The length of the trunk in the other direction remains unchanged, only the length of the branches at both ends changes, so there is only one changing function

[0049] Figure 7 and Figure 8 The normalized simulated and measured radiation patterns of the designed array operating at 6.5 GHz and 9.5 GHz are given, which are in good agreement. The E-plane sidelobe level and cross-polarization at 6.5 GHz are -19.82 dB and -41.22 dB, respectively, and the E-plane sidelobe level and cross-polarization at 9.5 GHz are -19.11 and -40.69 dB, respectively.

[0050] Fig. 9 and Fig.10The following is a measurement and simulation curve of the gain and aperture efficiency of the transmission array antenna as it changes with frequency. The maximum gain in the two frequency bands is 24.85dBi and 27.64dBi, respectively, and the corresponding aperture efficiency is 23.18% and 20.4%. At the same time, the transmission array antenna can achieve a 3-dB relative gain bandwidth of 15.6% and 22.34% in the two frequency bands, respectively.

[0051] This double-layer all-metal dual-band transmission array antenna unit enables the antenna to have dual-frequency operation function while achieving a transmission amplitude greater than -2dB and a 360° phase shift range. It simplifies the structure, reduces costs, has stable performance, and is simpler in design. It has the advantages of low profile, high gain, and simple structure. This design also avoids the insertion of additional metal column structures, and solves the inevitable polarization rotation problem of other units, and has better universality.

Claims

1. A double-layer all-metal dual-band transmission array antenna, characterized in that: The invention comprises a pyramidal horn antenna (1) and a transmission array (3), wherein the pyramidal horn antenna (1) is a feed source of the transmission array (3), and the transmission array (3) comprises two layers of metal plates (5), an air layer is arranged between the two layers of the metal plates (5), and a plurality of transmission units (4) are arranged on each of the metal plates (5), and the transmission units (4) are provided with two groups of first I-shaped slot structures (6) and third I-shaped slot structures (8) with different lengths and parallel to the x-direction, and two groups of second I-shaped slot structures (7) and fourth I-shaped slot structures (9) with different lengths and parallel to the y-direction.

2. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The second I-shaped slit structure (7) and the fourth I-shaped slit structure (9) are both periodically arranged on the transmission unit (4), with a period of P in the y direction and a period of P / 2 in the x direction.

3. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The first I-shaped slit structure (6) and the third I-shaped slit structure (8) are both periodically arranged on the transmission unit (4), with a period of P / 2 in the y direction and a period of P in the x direction.

4. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The geometric centers of the second I-shaped gap structure (7) and the fourth I-shaped gap structure (9) are P / 4 apart in the x direction and P / 2 apart in the x direction.

5. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The geometric centers of the first I-shaped gap structure (6) and the third I-shaped gap structure (8) are P / 2 apart in the x direction and P / 4 apart in the x direction.

6. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The two metal plates (5) are both square structures and have the same size.

7. The double-layer all-metal dual-band transmission array antenna according to claim 6, characterized in that: The size of the metal plate is 480 mm×480 mm.

8. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The transmission units (4) are periodically arranged on the metal plate (5).

9. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The spacing between the transmission units (4) is 30 mm.

10. The double-layer all-metal dual-band transmission array antenna according to claim 1, characterized in that: The first I-shaped slot structure (6), the third I-shaped slot structure (8), the second I-shaped slot structure (7) and the fourth I-shaped slot structure (9) have the same slot width.

Images