Line-to-circular polarization Huygens transmission array

Abstract

The invention relates to a line-to-circular polarization Huygens transmission array, which comprises a plurality of transmission array units arranged according to a square matrix form, each transmission array unit sequentially comprises a first metal layer, a dielectric substrate layer and a second metal layer from top to bottom, the first metal layer is located on the upper surface of the dielectric substrate layer, and the second metal layer is located on the lower surface of the dielectric substrate layer. The second metal layer is located on the lower surface of the dielectric substrate layer; the first metal layer comprises a C-like rectangular ring group arranged along the x direction and a C-like rectangular ring group arranged along the y direction; the second metal layer comprises a C-like rectangular ring group arranged along the x direction and a C-like rectangular ring group arranged along the y direction; the structures and sizes of the C-like rectangular ring groups placed in the x direction are the same, and the structures and sizes of the C-like rectangular ring groups placed in the y direction are the same. Compared with the prior art, the problem that an existing line-to-circular polarization transmission array antenna is low in aperture efficiency is solved, and the antenna has the function of focusing and converting a linear polarization spherical incident wave into a circular polarization plane transmission wave based on phase compensation.

Description

Technical Field

[0001] The present invention relates to the field of transmission array antennas, in particular to a linearly rotated circularly polarized Huygens transmission array. Background Art

[0002] A transmission array is a periodic array structure that can manipulate the phase and amplitude of incident electromagnetic waves, thereby forming a high-gain, focused beam in a specific direction. Transmission array antennas combine the advantages of lens antenna optical theory and planar array antenna theory, offering high gain, lightweight design, and low cost. They are widely used in long-distance wireless communication systems. Satellite communication, as a form of long-distance communication, requires antenna systems with high gain. Furthermore, when there is a polarization mismatch between transceivers in a satellite communication system, the signal will be severely attenuated during transmission, resulting in decreased communication quality or even interruption. To address this polarization mismatch, the use of circularly polarized waves is an effective technical solution. Therefore, high-gain circularly polarized transmission array antennas can meet the satellite communication system's need for circularly polarized, high-gain radiated waves. This can be achieved through a circularly polarized feed and a transmission array (the latter can focus the incident circularly polarized wave). However, this approach suffers from the drawback of complex circularly polarized feed design. In contrast, the solution using a linearly polarized feed combined with a transmission array has greater advantages. By converting linearly polarized spherical waves into circularly polarized plane waves, the transmission array can achieve high-gain circularly polarized radiation while significantly simplifying the feed structure. Currently, most research on linearly polarized transmission arrays uses receive-transmit or frequency-selective surface structures. Due to the inclusion of multiple dielectric substrate layers or metal vias, these structures are difficult to manufacture, exhibit unstable performance, and have low antenna aperture efficiency. In addition, the mainstream approach to conformal array design in existing technologies is to achieve curved conformality by bending ultra-thin arrays (thickness <0.8mm). If the structure contains metal vias, the structure may fracture and fail when bent, seriously restricting the feasibility of conformal design. China's patent application "CN118174044A" discloses a linear-to-circular-polarization transmission metasurface unit, which provides a single dielectric substrate and double metal layer structure without the need for metal vias, solving the problems of multiple dielectric substrate layers or metal vias being difficult to process, unstable performance, and difficult to conform. Top-layer patches and bottom-layer patches are printed on the upper and lower surfaces of the substrate respectively. The two layers of patches have the same size and shape and correspond in position. The top-layer patches and the bottom-layer patches are rectangular ring structures, and the four corners of the rectangular ring structure are chamfered so that the chamfers are located at the edge of the substrate and the edge lines are not broken. Although a solution is proposed to solve the problems existing in the prior art, it does not have functions such as beam focusing and cannot solve the problem of low aperture efficiency of the transmission array antenna.

[0003] Therefore, it is a technical problem that needs to be solved to provide a linear circular polarization transmission array that can achieve beam focusing, is easy to conformal, and has high aperture efficiency. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a linear-to-circular polarization Huygens transmission array. By using the Huygens metasurface theory, the structural complexity of the transmission array is reduced, the aperture efficiency of the transmission array antenna is improved, and the linear-to-circular polarization conversion performance is achieved. The transmission array unit provided by the present invention only contains a first metal layer, a dielectric substrate layer, and a second metal layer, and does not contain metal vias.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] The present invention provides a linear circular polarization Huygens transmission array, comprising:

[0007] A plurality of transmission array units are arranged periodically in a square array, wherein the transmission array units at different positions in the square array obtain the required transmission phase shift in each polarization direction by adjusting parameters in orthogonal polarization directions;

[0008] The transmission array unit includes, from top to bottom, a first metal layer, a dielectric substrate layer, and a second metal layer, wherein the first metal layer is located on the upper surface of the dielectric substrate layer, and the second metal layer is located on the lower surface of the dielectric substrate layer;

[0009] The first metal layer includes a C-shaped rectangular ring group placed along the x-direction and a C-shaped rectangular ring group placed along the y-direction; the second metal layer includes a C-shaped rectangular ring group placed along the x-direction and a C-shaped rectangular ring group placed along the y-direction; the C-shaped rectangular ring group consists of a pair of back-to-back C-shaped rectangular rings;

[0010] The C-shaped rectangular ring groups placed along the x-direction have the same structure and size, and the C-shaped rectangular ring groups placed along the y-direction have the same structure and size.

[0011] As a preferred technical solution, the phase of the transmitted wave of the transmission array unit satisfies:

[0012]

[0013] Where λ0 represents the wavelength of the electromagnetic wave in vacuum; (m,n) represents the coordinates of the transmission array unit, that is, the unit in the mth row and nth column on the transmission array aperture; L represents the distance between the (m,n) unit and the phase center of the feed source; F represents the focal length; Indicates the phase compensation of the (m,n) element on the array aperture.

[0014] As a preferred technical solution, the dielectric substrate layer of the transmission array unit is in a square shape.

[0015] As a preferred technical solution, the side length of the dielectric substrate layer of the transmission array unit satisfies p<λ0 / 2, wherein p represents the side length of the dielectric substrate layer of the transmission array unit; λ0 represents the wavelength of the electromagnetic wave in a vacuum.

[0016] As a preferred technical solution, the dielectric substrate layer of the transmission array unit has a side length of p=2.3 mm and a thickness of h=0.787 mm.

[0017] As a preferred technical solution, the length of the C-shaped rectangular ring group placed along the x direction is l x The length of the C-shaped rectangular ring group placed along the y direction is l y , the parameter adjustment is to adjust the l x and l y The transmission phase of the transmission array unit is adjusted, and the control range of the transmission phase of the transmission array unit is 330°. For the same transmission array unit, the transmission phase difference between orthogonal polarization directions at the center frequency is 90°.

[0018] As a preferred technical solution, when the transmission phase difference between the orthogonal polarization directions is ±90°, the transmitted wave of the transmission array is a circularly polarized wave.

[0019] As a preferred technical solution, the transmission array is used to convert a linearly polarized spherical incident wave with an electric field vector forming an angle of 45° with the x or y direction into a circularly polarized plane transmitted wave.

[0020] As a preferred technical solution, the electric field distribution of the linearly polarized incident wave is:

[0021]

[0022] in, represents the electric field distribution of the linearly polarized incident wave; E ix represents the x-polarized electric field component of the linearly polarized incident wave; represents the unit vector in the x direction; E iy represents the y-polarized electric field component of the linearly polarized incident wave; represents the unit vector in the y direction;

[0023] The electric field distribution of the circularly polarized transmitted wave is:

[0024]

[0025] in, represents the electric field distribution of the circularly polarized transmitted wave; S 21 represents the transmission coefficient; S 21x represents the x-polarization component of the transmission coefficient; S 21yrepresents the y-polarization component of the transmission coefficient.

[0026] As a preferred technical solution, when a linearly polarized spherical electromagnetic wave with an electric field vector at a 45° angle to the x or y direction is incident, the incident wave can be decomposed into electromagnetic wave components with equal amplitudes in the x-polarization and y-polarization directions. When the x- or y-polarization electromagnetic wave components are incident, the first metal layer and the second metal layer generate surface induced currents, and in the first and third quarter time periods, the directions of the surface induced currents of the first metal layer and the second metal layer are the same; in the second and fourth quarter time periods, the directions of the surface induced currents of the first metal layer and the second metal layer are opposite, forming a current loop, which is equivalent to having The equivalent magnetic current of time delay, where T represents one time period of the electromagnetic wave.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1) The present invention achieves phase control of the transmission array unit by adjusting the length of the C-shaped rectangular ring group placed along the x-direction in the first metal layer and the second metal layer, and the C-shaped rectangular ring group placed along the y-direction in the first metal layer and the second metal layer. The transmission array unit with such phase control capability is used to form an array to achieve a beam focusing function based on phase control, thereby achieving a high-gain beam.

[0029] 2) The transmission array provided by the present invention is based on the Huygens metasurface theory. When an electromagnetic wave is incident on the transmission array provided by the present invention, the scattering field of the induced current and magnetic current caused by the metasurface structure can interact with the incident wave to produce Huygens resonance with full transmission and non-reflection characteristics, thereby improving the transmission focusing efficiency of the incident wave and reducing the loss, and can convert the linearly polarized spherical incident wave into a circularly polarized plane transmitted wave, thereby improving the aperture efficiency of the linear-to-circularly polarized transmission array antenna.

[0030] 3) The present invention provides a transmission array with a simple structure, which includes multiple transmission array units arranged periodically in a square array. The transmission array unit has a simple structure, including only a dielectric substrate layer without metal vias and two metal layers. It not only solves the problems of the existing linear-to-circular polarization transmission array caused by the inclusion of multiple dielectric substrate layers or metal vias, such as high processing difficulty, unstable performance, and difficulty in conformality. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of the structure of the reference transmission array unit of the present invention;

[0032] Figure 2 A top view of a reference transmission array unit of the present invention;

[0033] Figure 3 A bottom view of a reference transmission array unit of the present invention;

[0034] Figure 4 Schematic diagram of the structure of the reference transmission array antenna of the present invention;

[0035] Figure 5 This is a principle diagram of the relationship between the reference transmission array phase compensation and the transmission array unit positions of the present invention;

[0036] Figure 6 Schematic diagram of the x-polarization phase distribution of the reference transmission array of the present invention;

[0037] Figure 7 Schematic diagram of the y-polarization phase distribution of the reference transmission array of the present invention;

[0038] Figure 8 is a graph showing the relationship between the transmission amplitude and phase and frequency for the reference transmission array unit of the present invention at x and y polarizations;

[0039] Figure 9 The transmission amplitude and phase of the reference transmission array unit of the present invention at the center frequency x and y polarization are related to the parameter l x and l y The relationship curve diagram;

[0040] Figure 10 The current distribution diagram of the first and second metal layers of the reference transmission array unit of the present invention at the center frequency x-polarization;

[0041] Figure 11 The current distribution diagram of the first and second metal layers of the reference transmission array unit of the present invention on the y-polarization at the center frequency;

[0042] Figure 12 Schematic diagram of left-hand and right-hand circular polarization reflection coefficients of the reference transmission array antenna of the present invention;

[0043] Figure 13 is the left-hand circularly polarized radiation pattern of the reference transmission array antenna of the present invention operating at the center frequency;

[0044] Figure 14 is the right-hand circular polarization pattern of the reference transmission array antenna of the present invention operating at the center frequency;

[0045] Figure 15 is a graph showing the relationship between the left-hand and right-hand circular polarization gains and aperture efficiency and frequency of the reference transmission array of the present invention;

[0046] Figure 16 Schematic diagram of the relationship between the left-hand and right-hand circular polarization axis ratios and frequency of the reference transmission array of the present invention. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0048] Unless otherwise defined, the technical or scientific terms used in this application should have the ordinary meaning understood by a person of ordinary skill in the technical field to which this application belongs. The words "one", "a", "the" and the like used in this application do not indicate a limit on quantity and may indicate the singular or plural. The terms "include", "comprise", "have" and any variations thereof used in this application are intended to cover non-exclusive inclusions; for example, a process, method, system, product or device that includes a series of steps or modules (units) is not limited to the listed steps or units, but may also include steps or units that are not listed, or may also include other steps or units that are inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like used in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The word "multiple" used in this application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the objects before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in this application are only used to distinguish similar objects and do not represent a specific order for the objects.

[0049] Example 1

[0050] Existing linear-to-circular polarization transmission arrays face three main technical bottlenecks: First, the complex configuration of multi-layer metal structures, some of which contain metal vias, significantly increases the difficulty of processing and can easily lead to unstable array performance due to manufacturing errors; second, in terms of conformal array design, the mainstream solution is to achieve surface conformality by bending ultra-thin arrays (thickness <0.8mm), but structures containing metal vias are prone to fracture and failure when bent, which seriously restricts the feasibility of conformal design; third, existing linear-to-circular polarization transmission arrays generally have the problem of low aperture efficiency.

[0051] Based on the above reasons, the present invention proposes an innovative solution based on the Huygens metasurface principle: by optimizing the unit structure design, while maintaining a single-layer ultra-thin substrate (thickness 0.787mm), abandoning the traditional multi-layer and partially metal via structure, only using one dielectric substrate layer and two metal layers, not only can it significantly improve the processing reliability, but also can maintain structural integrity during the bending process, and it is easy to realize conformal arrays. In detail, the Huygens metasurface is a metasurface structure that can theoretically achieve lossless transmission. The scattering field of the induced current and magnetic current caused by the metasurface structure can generate a transmission field by interacting with the incident wave. Its unit structure consists of an electric response part and a magnetic response part, which respectively regulate the electric field and the magnetic field, thereby realizing free regulation of electromagnetic waves. The electromagnetic properties of the Huygens metasurface can be expressed by the surface electrical admittance Y ES and surface magnetic impedance Z MS To describe it, the lower right subscript S represents the surface distribution of this function, the lower right subscript E indicates that this term is related to the equivalent current of the Huygens surface, and the lower right subscript M indicates that this term is related to the equivalent magnetic current of the Huygens surface. According to the derivation, the relationship between the surface electrical admittance and the reflection coefficient and transmission coefficient on the metasurface is:

[0052]

[0053] Where η0 represents the free space wave impedance; T represents the transmission coefficient; and R represents the reflection coefficient.

[0054] The relationship between surface magnetic impedance and reflection coefficient and transmission coefficient is:

[0055]

[0056] Where η0 represents the free space wave impedance; T represents the transmission coefficient; and R represents the reflection coefficient.

[0057] The transmission array provided by the present invention includes a plurality of transmission array units arranged periodically in a square matrix, and its structure is as follows: Figure 1 shown.

[0058] The specific transmission array unit includes a first metal layer 1, a dielectric substrate layer 2 and a second metal layer 3 from top to bottom, wherein the first metal layer 1 is located on the upper surface of the dielectric substrate layer 2, and the second metal layer 3 is located on the lower surface of the dielectric substrate layer 2.

[0059] The dielectric substrate layer 2 of the transmission array unit is square in shape, and the side length of the transmission array unit satisfies p<λ0 / 2, where p represents the side length of the dielectric substrate layer 2 of the transmission array unit; λ0 represents the wavelength of the electromagnetic wave in a vacuum. In this embodiment, the side length of the dielectric substrate layer of the transmission array unit is set to p = 2.3 mm, and the selected dielectric substrate layer model is Taconic TLY-5, with a relative dielectric constant of 2.2 and a thickness of h = 0.787 mm.

[0060] The first metal layer 1 includes a C-shaped rectangular ring group 101 placed along the x-direction and a C-shaped rectangular ring group 102 placed along the y-direction; the C-shaped rectangular ring group 101 and the C-shaped rectangular ring group 102 are composed of a pair of back-to-back C-shaped rectangular rings. The second metal layer 3 includes a C-shaped rectangular ring group 301 placed along the x-direction and a C-shaped rectangular ring group 302 placed along the y-direction; the C-shaped rectangular ring group 301 and the C-shaped rectangular ring group 302 are composed of a pair of back-to-back C-shaped rectangular rings; the C-shaped rectangular ring group 101 and the C-shaped rectangular ring group 301 have the same structure and size, and the C-shaped rectangular ring group 102 and the C-shaped rectangular ring group 302 have the same structure and size. In the first metal layer and the second metal layer, the length of the C-shaped rectangular ring group 101 and the C-shaped rectangular ring group 301 placed along the x-direction is l x The length of the C-shaped rectangular ring group 102 and the C-shaped rectangular ring group 302 placed along the y direction is l y , its placement effect is as follows Figure 2 and Figure 3 shown.

[0061] In this embodiment, the width of the C-shaped ring is set to d = 0.3 mm, the width of the metal is set to w = 0.1 mm, the distance between a pair of back-to-back C-shaped rings is set to g = 0.1 mm, and the length of the opening on the C-shaped ring is set to s = 0.127 mm; the distance between the short side of the C-shaped ring and the unit edge is set to a = 0.05 mm, and the distance between the long side of the C-shaped ring with the opening and the unit edge is set to b = 0.225 mm. By adjusting the parameters of the transmission array units at different positions in the array in the orthogonal polarization directions, the required transmission phase shift in each polarization direction is obtained, that is, adjusting l x and l y The transmission phase can be adjusted within a range of 330°, and the transmission phase difference between orthogonal polarizations in the same transmission array unit is 90°. Specifically, when the transmission phase difference between orthogonal polarization directions is ±90°, the transmission wave of the transmission array is a circularly polarized wave.

[0062] The transmission array of the present invention is used to convert a linearly polarized spherical incident wave with an electric field vector at an angle of 45° to the x or y direction into a circularly polarized plane transmitted wave, and the phase of the transmitted wave satisfies:

[0063]

[0064] Where λ0 represents the wavelength of the electromagnetic wave in vacuum; (m,n) represents the coordinates of the transmission array unit, that is, the unit in the mth row and nth column on the transmission array aperture; L represents the distance between the (m,n) unit and the phase center of the feed source; F represents the focal length; Indicates the phase compensation of the (m,n) element on the array aperture.

[0065] The electric field of a linearly polarized incident wave can be decomposed into two orthogonal components with equal amplitudes in the x and y directions, which are expressed as follows:

[0066]

[0067] in, represents the electric field distribution of the linearly polarized incident wave; E ix represents the x-polarized electric field component of the linearly polarized incident wave; represents the unit vector in the x direction; E iy represents the y-polarized electric field component of the linearly polarized incident wave; represents the unit vector in the y direction;

[0068] The electric field distribution of the circularly polarized transmitted wave is:

[0069]

[0070] in, represents the electric field distribution of the circularly polarized transmitted wave; S 21 represents the transmission coefficient; S 21x represents the x-polarization component of the transmission coefficient; S 21y represents the y-polarization component of the transmission coefficient.

[0071] When the x- or y-polarized electromagnetic wave component enters the transmission array unit, the first metal layer 1 and the second metal layer 3 generate surface induced currents. In the first and third quarter time periods, the directions of the surface induced currents of the first metal layer 1 and the second metal layer 3 are the same; in the second and fourth quarter time periods, the directions of the surface induced currents of the first metal layer 1 and the second metal layer 3 are opposite, forming a current loop. The current loop is equivalent to The equivalent magnetic current with time delay, where T represents a time period of the electromagnetic wave, occurs in phase with the equivalent current and the equivalent magnetic current in the orthogonal direction, and a Huygens resonance along the x or y polarization is generated in the transmission array unit.

[0072] Example 2

[0073] In order to verify the feasibility and superiority of the transmission array provided in the above embodiment, a transmission array is constructed in this embodiment. Figure 4 The structure of the reference transmission array antenna is shown in Figure 4The principle of the relationship between the reference transmission array phase compensation and the transmission array unit position in the structure is as follows Figure 5 In this embodiment, when a linearly polarized spherical electromagnetic wave with an electric field vector and an angle of 45° between the x and y directions is incident on the transmission array, the x and y polarization phase distributions are as follows: Figure 6 and Figure 7 As shown, we can get Figure 8 The relationship between the transmission amplitude and phase of the reference transmission array unit in the x and y polarizations and the frequency is shown. The left arrow in the figure represents the amplitude curve, and the right arrow represents the phase curve. It can be seen from the figure that the transmission phase range of the reference transmission array unit in the x and y polarizations in the frequency range of 50 GHz to 70 GHz is 340° and the transmission amplitude is greater than -1.3 dB. The transmission phase difference between the x and y polarizations is 90° at the center frequency of 60 GHz.

[0074] In addition, this embodiment also verifies that the adjustment l x and l y The transmission phase and amplitude changes when the reference transmission array unit works at 60GHz on the x and y polarizations and the parameter l x and l y The relationship as Figure 9 As shown in the figure, the left arrow represents the amplitude curve, and the right arrow represents the phase curve. It can be seen from the figure that when the reference transmission array unit works at 60GHz, by adjusting the parameter l x and l y With the value of , a transmission phase range of 330° and a transmission amplitude greater than -1.2dB can be achieved in both x and y polarizations.

[0075] At the same time draw Figure 10 and Figure 11 Current distribution diagrams of the first and second metal layers on a reference transmission array unit operating at 60 GHz for x and y polarizations. This verifies the conclusion that when x- or y-polarized electromagnetic waves are incident on the transmission array unit, surface induced currents are generated in the first and second metal layers 1 and 3. During the first and third quarter-time periods, the surface induced currents in the first and second metal layers 1 and 3 are in the same direction; during the second and fourth quarter-time periods, the surface induced currents in the first and second metal layers 1 and 3 are in opposite directions.

[0076] Under the conditions of this embodiment, the left and right circular polarization reflection coefficients of the reference transmission array antenna are as follows: Figure 12 As shown, the corresponding drawable is Figure 13 and Figure 14The left-hand and right-hand circular polarization radiation patterns of the reference transmission array antenna shown in the figure when operating at 60GHz can be seen. The radiation pattern beam width of the transmission array antenna is narrow, which can achieve higher pointing accuracy and greater gain, so that the transmission array of the present invention has a more efficient focusing effect. Figure 15 Figure 2 is the relationship between the left-hand and right-hand circular polarization gain and aperture efficiency of the reference transmission array of the present invention and the frequency. It can be seen that the reference transmission array antenna of the present invention maintains high gain and high efficiency characteristics within a large bandwidth. Figure 16 The relationship between the left-hand and right-hand circular polarization axis ratios and frequency of the reference transmission array of the present invention is shown. The reference transmission array antenna of the present invention maintains good circular polarization characteristics within a larger bandwidth. In summary, the transmission array provided by the present invention has feasibility and advantages.

[0077] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A linear circular polarization Huygens transmission array, characterized in that: include: A plurality of transmission array units are arranged periodically in a square array, wherein the transmission array units at different positions in the square array obtain the required transmission phase shift in each polarization direction by adjusting parameters in orthogonal polarization directions; The transmission array unit comprises, from top to bottom, a first metal layer (1), a dielectric substrate layer (2), and a second metal layer (3), wherein the first metal layer (1) is located on the upper surface of the dielectric substrate layer (2), and the second metal layer (3) is located on the lower surface of the dielectric substrate layer (2); The first metal layer (1) comprises a C-shaped rectangular ring group (101) placed along the x-direction and a C-shaped rectangular ring group (102) placed along the y-direction; the C-shaped rectangular ring group (101) and the C-shaped rectangular ring group (102) are composed of a pair of back-to-back C-shaped rectangular rings; The second metal layer (3) comprises a C-shaped rectangular ring group (301) placed along the x-direction and a C-shaped rectangular ring group (302) placed along the y-direction; the C-shaped rectangular ring group (301) and the C-shaped rectangular ring group (302) are composed of a pair of back-to-back C-shaped rectangular rings; The C-shaped rectangular ring group (101) and the C-shaped rectangular ring group (301) have the same structure and size, and the C-shaped rectangular ring group (102) and the C-shaped rectangular ring group (302) have the same structure and size.

2. The linear circular polarization Huygens transmission array according to claim 1, characterized in that: The phase of the transmission wave of the transmission array unit satisfies: Where λ0 represents the wavelength of the electromagnetic wave in vacuum; (m,n) represents the coordinates of the transmission array unit, that is, the unit in the mth row and nth column on the transmission array aperture; L represents the distance between the (m,n) unit and the phase center of the feed source; F represents the focal length; Indicates the phase compensation of the (m,n) element on the array aperture.

3. The linear circular polarization Huygens transmission array according to claim 1, characterized in that: The dielectric substrate layer (2) of the transmission array unit is in the shape of a square.

4. The linear circular polarization Huygens transmission array according to claim 3, characterized in that: The side length of the dielectric substrate layer (2) of the transmission array unit satisfies p<λ0 / 2, wherein p represents the side length of the dielectric substrate layer (2) of the transmission array unit; and λ0 represents the wavelength of electromagnetic waves in a vacuum.

5. The linear circular polarization Huygens transmission array according to claim 3, characterized in that: The dielectric substrate layer (2) of the transmission array unit has a side length of p=2.3 mm and a thickness of h=0.787 mm.

6. The linear circular polarization Huygens transmission array according to claim 1, characterized in that: The length of the C-shaped rectangular ring group (101) and the C-shaped rectangular ring group (301) is l x The length of the C-shaped rectangular ring group (102) and the C-shaped rectangular ring group (302) is l y , the parameter adjustment is to adjust the l x and l y The transmission phase of the transmission array unit is adjusted, and the control range of the transmission phase of the transmission array unit is 330°. For the same transmission array unit, the transmission phase difference between orthogonal polarization directions at the center frequency is 90°.

7. The linear circular polarization Huygens transmission array according to claim 1, characterized in that: When the transmission phase difference between the orthogonal polarization directions is ±90°, the transmitted wave of the transmission array is a circularly polarized wave.

8. The linear circular polarization Huygens transmission array according to claim 1, characterized in that: The transmission array is used to convert a linearly polarized spherical incident wave with an electric field vector and an x ​​or y direction forming an angle of 45 degrees into a circularly polarized plane transmitted wave.

9. The linear circular polarization Huygens transmission array according to claim 8, characterized in that: The electric field distribution of the linearly polarized incident wave is: in, represents the electric field distribution of the linearly polarized incident wave; E ix represents the x-polarized electric field component of the linearly polarized incident wave; represents the unit vector in the x direction; E iy represents the y-polarized electric field component of the linearly polarized incident wave; represents the unit vector in the y direction; The electric field distribution of the circularly polarized transmitted wave is: in, represents the electric field distribution of the circularly polarized transmitted wave; S 21 represents the transmission coefficient; S 21x represents the x-polarization component of the transmission coefficient; S 21y represents the y-polarization component of the transmission coefficient.

10. The linear circular polarization Huygens transmission array according to claim 8, characterized in that: When a linearly polarized spherical electromagnetic wave with an electric field vector and an angle of 45° between the x-direction and the y-direction is incident, the incident wave can be decomposed into electromagnetic wave components with equal amplitudes in the x-polarization and y-polarization directions; when the x-polarization or y-polarization electromagnetic wave components are incident, the first metal layer (1) and the second metal layer (3) generate surface induced currents, and in the first and third quarter time periods, the directions of the surface induced currents of the first metal layer (1) and the second metal layer (3) are the same; in the second and fourth quarter time periods, the directions of the surface induced currents of the first metal layer (1) and the second metal layer (3) are opposite, forming a current loop, which is equivalent to having The equivalent magnetic current of time delay, where T represents one time period of the electromagnetic wave.

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