Broadband multi-polarization multi-beam independent regulation reflection type metasurface and design method thereof

Abstract

The invention discloses a broadband multi-polarization multi-beam independent regulation reflective metasurface and a design method thereof, relates to the technical field of electromagnetic metamaterials and artificial electromagnetic surfaces, and aims to solve the problem that a metasurface in the prior art generally only supports single polarization or a fixed beam direction so as to realize independent regulation of a plurality of polarization channels. According to the metasurface provided by the invention, a plurality of metasurface units form a two-dimensional array, each metasurface unit is based on a diagonally symmetrical I-shaped metasurface unit, and independent regulation and control of x polarized waves, y polarized waves, left-hand circularly polarized waves and right-hand circularly polarized waves are realized by calculating a cross polarization reflection phase and a unit rotation angle required by the position of each unit. Through phase distribution optimization design, a plurality of reflection beams with adjustable polarization channel directions can be generated in a broadband at the same time, and the antenna has remarkable advantages in anti-interference capability and system complexity reduction.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic metamaterials and artificial electromagnetic surfaces, and specifically relates to a reflective metasurface structure with broadband multi-polarization and multi-beam independent regulation and its design method, which can be applied to the regulation of multi-polarization electromagnetic waves. Background Art

[0002] A metasurface is an artificial electromagnetic material composed of sub-wavelength unit structures, which can flexibly regulate the phase, amplitude, polarization, etc. of electromagnetic waves. Compared with traditional optical devices, the metasurface has the advantages of low profile, light weight, and easy integration, and has wide applications in the fields of communication, radar, stealth technology, etc. Polarization is an important characteristic of electromagnetic waves, including linear polarization (TE / TM), circular polarization (left-handed / right-handed), etc. In the prior art, the metasurface has been able to achieve single-polarization regulation. However, in multi-polarization regulation, there are still problems such as electromagnetic coupling between channels, complex unit design, insufficient dynamic regulation ability, and small working bandwidth, which limit its application in many mission scenarios. Summary of the Invention

[0003] Object of the Invention: Aiming at the deficiencies of the prior art, the object of the present invention is a reflective metasurface with broadband multi-polarization and multi-beam independent regulation and its design method, which can simultaneously generate multiple reflection beams with adjustable directions of different polarization channels within a broadband, and has the advantages of strong anti-interference ability and low system complexity.

[0004] Technical Solution: To achieve the above object of the invention, the present invention adopts the following technical solutions:

[0005] In a first aspect, the present invention provides a reflective metasurface with broadband multi-polarization and multi-beam independent regulation, which is composed of a two-dimensional array of multiple metasurface units. Each metasurface unit is based on a diagonal-symmetric "I"-type metasurface unit. By calculating the cross-polarization reflection phase and unit rotation angle required for each unit position, independent regulation of x-polarized waves, y-polarized waves, left-handed circularly polarized waves, and right-handed circularly polarized waves is achieved; the diagonal-symmetric "I"-type metasurface unit ensures that the cross-polarization reflectivity is above a set threshold at the center frequency by changing the size parameters, and the cross-polarization reflection phase uniformly covers the full range.

[0006] Further, the cross-polarization reflection phase of the unit and the unit rotation angle θ have the following phase distribution relationship with the four reflection channels

[0007]

[0008] where mn represents the position of the mn-th unit, and respectively represent the phase distributions of the x-polarized wave, y-polarized wave, left-handed circularly polarized wave, and right-handed circularly polarized wave, j represents the imaginary unit, and arg represents the argument function.

[0009] Furthermore, the "I"-type metasurface unit is formed by etching an "I"-type structured metal patch on a dielectric substrate with a metal backplane. The patch consists of two radius edges and two arc edges. When designing the diagonally symmetric "I"-type metasurface unit, first design the unit so that the phase covers 0 - 180°, and then rotate the designed unit by 90° respectively so that the phase covers 0 - 360°.

[0010] Furthermore, the period of the metasurface unit is 0.27 - 0.29λ, the thickness of the substrate dielectric is 0.132 - 0.148λ, the material is F4B board, the radius of the "I"-type structured metal patch is 0.112λ - 0.0896λ, the width of the radius edge is 0.016λ - 0.018λ, the included angle of the arc edge is 80° - 160°, and the width is 0.0216λ - 0.024λ, where λ is the operating wavelength.

[0011] In a second aspect, the present invention provides a design method for a broadband multi-polarization multi-beam independently controllable reflective metasurface for the broadband multi-polarization multi-beam independently controllable reflective metasurface, including the steps:

[0012] Step S1, independently control the left-handed circularly polarized wave and the right-handed circularly polarized wave according to the cross-polarization reflection phase and rotation angle of the unit;

[0013] Step S2, calculate the phase distributions of the beams in the target directions respectively according to the generalized Snell's law;

[0014] Step S3, represent the total reflected field as the superposition of the left-handed circularly polarized wave and the right-handed circularly polarized wave;

[0015] Step S4, independently control the reflection phases of the four polarization channels with the cross-polarization reflection phase and rotation angle of the unit.

[0016] Furthermore, in the step S1, specifically includes:

[0017] Step S11, for the diagonally symmetric unit, the diagonal terms of the Jones matrix become 0, and the Jones matrix is simplified to

[0018]

[0019] Step S12, introduce the unit rotation angle θ, for the rotated unit, its Jones matrix is expressed as

[0020]

[0021] When an x-polarized wave is incident, the reflected field is expressed as

[0022]

[0023] The first term is the left - hand circularly polarized wave, and the second term is the right - hand circularly polarized wave. Then

[0024]

[0025] wherein, is the phase of the left - hand circularly polarized wave, is the phase of the right - hand circularly polarized wave. By adjusting the cross - polarization reflection phase and the unit rotation angle θ, independent control of the left - hand circularly polarized wave and the right - hand circularly polarized wave can be achieved.

[0026] Furthermore, in the step S2, the designed target reflection wave deflection phase is that the x - polarized wave deflects by θ in the - x direction x , the y - polarized wave deflects by θ in the - y direction y , the right - hand circularly polarized wave deflects by θ in the x direction R , and the left - hand circularly polarized wave deflects by θ in the y direction L ; According to the generalized Snell's law for normal incidence:

[0027]

[0028] where θ r is the exit angle, n r is the refractive index of the exit medium, λ0 is the operating wavelength, dφ is the phase difference between adjacent units, and dx is the unit period. The phases required for the four reflection channels can be designed as

[0029]

[0030] wherein, is the phase of the x - polarized wave, is the phase of the y - polarized wave, is the phase of the right - hand circularly polarized wave, is the phase of the left - hand circularly polarized wave.

[0031] Furthermore, in the step S3, when an x - polarized wave is incident, the total reflection field E of any single metasurface unit mn can be regarded as the superposition of the reflection fields in each polarization channel:

[0032]

[0033] wherein, are the reflection fields of the x - polarization, y - polarization, right - hand circular polarization, and left - hand circular polarization channels respectively;

[0034] Expressing the linearly polarized wave in terms of the circular polarization basis gives:

[0035]

[0036] Among them, mn represents the position of the mn-th unit, and E x , E y , E r , E l respectively represent the amplitude values of the x-polarized, y-polarized, right-handed circularly polarized, and left-handed circularly polarized waves. The total reflected field is a superposition of three left-handed circularly polarized waves and three right-handed circularly polarized waves.

[0037] Furthermore, in the step S4, according to the phase addition operation:

[0038]

[0039] Among them, represents the total phase distribution, represents the phase distribution of the q-th channel, N is the number of channels, is the compensation phase, then the total phase of the left-handed circularly polarized wave component in the total reflected field is

[0040]

[0041] The total phase of the right-handed circularly polarized wave component is

[0042]

[0043] Since the unit has achieved independent control of the left-handed circularly polarized wave and the right-handed circularly polarized wave, the four reflection channels can be independently controlled by the cross-polarization reflection phase of the unit and the unit rotation angle θ. The formula is

[0044]

[0045] Thirdly, the present invention provides a computer program product, including a computer program, and when the computer program is executed by a processor, it implements the steps of the design method of a broadband multi-polarization multi-beam independent control reflective metasurface.

[0046] Beneficial effects: Compared with the prior art, the present invention can independently control the directions of the reflected waves of the four polarization channels according to the designed deflection angle to meet the reflection requirements of different polarization waves. Experiments show that for the broadband multi-polarization multi-beam independent control reflective metasurface designed by the present invention, the cross-polarization reflectivity of the metasurface unit is greater than 0.9 at the center frequency, and the energy loss is small. In the working frequency band of 8 - 12 GHz, the deflection angle error of the reflected wave does not exceed 1°, and it has good broadband performance. Description of the Drawings

[0047] Figure 1It is the overall structure diagram of the metasurface unit.

[0048] Figure 2 It is the simulation result diagram of the cross-polarization reflectivity of 18 units in the embodiment.

[0049] Figure 3 It is the metasurface phase arrangement diagram in the embodiment.

[0050] Figure 4 It is the overall structure diagram of the arranged metasurface in the embodiment.

[0051] Figure 5 It is the far-field pattern of the simulated metasurface in the embodiment.

[0052] Figure 6 It is the far-field pattern in the xoz plane in the embodiment.

[0053] Figure 7 It is the far-field pattern in the yoz plane in the embodiment.

[0054] Figure 8 It is the diagram of the variation of the four-channel beam deflection angle with frequency in the embodiment. Specific implementation manner

[0055] To make the technical solutions and objectives of the present invention clearer, the technical solutions of the embodiments of the present invention will be described clearly and completely below. The described embodiments are part of the embodiments of the present invention, rather than all of the embodiments.

[0056] A reflective metasurface for broadband multi-polarization and multi-beam independent regulation disclosed in an embodiment of the present invention is composed of a two-dimensional array of multiple metasurface units. Each metasurface unit is based on a diagonally symmetric "I"-type metasurface unit. By calculating the cross-polarization reflection phase and unit rotation angle required for each unit position, independent regulation of x-polarized waves, y-polarized waves, left-handed circularly polarized waves, and right-handed circularly polarized waves is achieved. The diagonally symmetric "I"-type metasurface unit is formed by etching an "I"-type metal structure patch on a dielectric substrate with a metal backplane. For this diagonally symmetric unit, the diagonal terms of its Jones matrix become 0. By changing the size parameters of the metal patch, units with different design parameters are designed to maintain a high cross-polarization reflectivity within the working frequency band, and the cross-polarization reflectivity is guaranteed to be above a set threshold at the center frequency, and the cross-polarization reflection phase uniformly covers the entire range.

[0057] In the specific design, the period of the metasurface unit is 0.27 - 0.29λ, the thickness of the substrate dielectric is 0.132 - 0.148λ, the material is F4B board, the radius of the metal patch of the "I"-shaped structure is 0.112λ - 0.0896λ, the width of the radius side is 0.016λ - 0.018λ, the opening angle of the arc side is 80° - 160°, and the width is 0.0216λ - 0.024λ, where λ is the operating wavelength.

[0058] A design method of a broadband multi-polarization multi-beam independent regulation reflective metasurface disclosed in an embodiment of the present invention introduces a unit rotation angle, obtains the Jones matrix of the rotated unit, calculates and realizes the independent regulation of the phases of the left-handed circularly polarized wave and the right-handed circularly polarized wave by the cross-polarized reflection phase and the unit rotation angle. A metasurface phase arrangement method is designed to enable the free and independent control of the four reflected channel beams when an incident linearly polarized wave is present, and the required beam deflection angle can be achieved in each channel. The incident wave is defined as an x-polarized wave. The four reflected channels designed by this method are two orthogonal linearly polarized channels of x-polarization (co-polarization) and y-polarization (cross-polarization), and two orthogonal circularly polarized channels of left-handed circularly polarized wave and right-handed circularly polarized wave. The required phase distribution of each reflected channel is calculated according to the generalized Snell's law. Any linearly polarized wave can be decomposed into a combination of a left-handed circularly polarized wave and a right-handed circularly polarized wave. Representing the required linearly polarized reflection phase in the circular polarization basis, the total reflected field can be expressed as the superposition of the left-handed circularly polarized wave and the right-handed circularly polarized wave. Since the unit described above can already achieve the independent regulation of the left-handed circularly polarized wave and the right-handed circularly polarized wave, the independent regulation of the four reflected channels can be calculated and realized.

[0059] Through the CST electromagnetic simulation software, the far-field pattern after the plane wave is reflected by this metasurface can be drawn. A far-field monitor is added every 0.5 GHz within the working frequency band. The error between the reflected beam and the theoretical design within the working frequency band does not exceed 1°. It can be seen that the broadband performance of this metasurface is good.

[0060] In this embodiment, taking the working frequency band of 8 - 16 GHz and the center frequency of 12 GHz as an example, a metasurface unit is designed in this embodiment, which is formed by etching a metal patch of the "I"-shaped structure on a dielectric substrate with a metal backplane as Figure 1 shown. Its specific parameters are that the unit period d = 7 mm. The thickness of the substrate dielectric h = 3.5 mm, and the material is F4B board with a relative dielectric constant of 2.65 and a loss tangent of 0.001. The size parameters of the metal patch of the "I"-shaped structure are that the radius r = 2.24 mm, the width of the radius side w2 = 0.42 mm, the opening angle of the arc side width w1 = 0.56 mm, and the material is copper.

[0061] In one embodiment, by changing the size parameters of the metal patch, cells with different design parameters are designed to maintain a high cross-polarization reflectivity within the operating frequency band, and the cross-polarization reflectivity is above 0.9 at the center frequency, and the cross-polarization reflection phase uniformly covers 360°.

[0062] In this embodiment, since the cell is a diagonally symmetric cell, it remains diagonally symmetric after rotating 90°, and the cross-polarization phase will add a phase difference of 180°. Therefore, only need to design the cell so that the phase covers 0-180°, and then rotate the designed cells by 90° respectively, then the phase can cover 0-360°. The size table of the 18 different cells designed is shown in Table 1:

[0063] Table 1 Cell Size Table

[0064]

[0065] Among them, represents the central angle of the arc, θ0 represents the rotation angle, r represents the radius length, represents the cross-polarization reflection phase. The simulation results of the cells in the CST electromagnetic simulation software are as Figure 2 shown. The cross-polarization reflectivity of these 18 cells is above 0.9 at the center frequency, and the energy loss is small.

[0066] The specific design method of this broadband multi-polarization multi-beam independent regulation reflective metasurface includes:

[0067] Step S1: Independently regulate the left-handed circularly polarized wave and the right-handed circularly polarized wave according to the cross-polarization reflection phase and rotation angle of the cell.

[0068] Specifically, the Jones matrix of the reflective cell is

[0069]

[0070] The first subscript represents the reflected polarization state, and the second represents the incident polarization state. For the diagonally symmetric cell designed in this scheme, the diagonal terms of the Jones matrix become 0, and the Jones matrix can be simplified to

[0071]

[0072] Introduce the cell rotation angle θ. For the rotated cell, its Jones matrix can be expressed as

[0073]

[0074] Among them, represents the Jones matrix of the rotation factor.

[0075] When an x-polarized wave is incident, the reflected field is expressed as

[0076]

[0077] It can be seen that the first term is a left - hand circularly polarized wave and the second term is a right - hand circularly polarized wave. Then

[0078]

[0079] wherein, is the phase of the left - hand circularly polarized wave, is the phase of the right - hand circularly polarized wave. Therefore, by adjusting the propagation phase and the unit rotation angle θ, independent control of the left - hand circularly polarized wave and the right - hand circularly polarized wave can be achieved.

[0080] Step S2: Calculate the phase distribution of the beam in the target direction according to the generalized Snell's law respectively.

[0081] In this embodiment, the designed deflection phase of the target reflected wave is that the x - polarized wave deflects 10° in the - x direction, the y - polarized wave deflects 12° in the - y direction, the right - hand circularly polarized wave deflects 15° in the x direction, and the left - hand circularly polarized wave deflects 18° in the y direction.

[0082] Specifically, according to the generalized Snell's law at normal incidence:

[0083]

[0084] where θ r is the exit angle, n r is the refractive index of the exit medium (1 in air), λ0 is the operating wavelength, dφ is the phase difference between adjacent units, that is, the phase gradient to be designed, and dx is the unit period. The phases required for the four reflection channels can be designed as:

[0085]

[0086] wherein, is the phase of the x - polarized wave, is the phase of the y - polarized wave, is the phase of the right - hand circularly polarized wave, is the phase of the left - hand circularly polarized wave.

[0087] Step S3: Represent the total reflected field as the superposition of the left - hand circularly polarized wave and the right - hand circularly polarized wave.

[0088] Specifically, when the x - polarized wave irradiates on the metasurface, the total reflected field E mn of any single meta - unit can be regarded as the superposition of the reflected fields in each polarization channel:

[0089]

[0090] wherein, The reflected fields of the x-polarized, y-polarized, right-handed circularly polarized, and left-handed circularly polarized channels, respectively.

[0091] Expressing the linearly polarized wave in terms of the circular polarization basis gives:

[0092]

[0093] where mn represents the position of the mn-th unit, and E x , E y , E r , E l represent the amplitude values of the x-polarized, y-polarized, right-handed circularly polarized, and left-handed circularly polarized waves, respectively. Since the amplitude mainly affects the radiation efficiency and sidelobe level but has little effect on the main beam direction, the influence of the amplitude term can be ignored during calculation. According to the formula, the total reflected field can be divided into the superposition of three left-handed circularly polarized waves and three right-handed circularly polarized waves.

[0094] Step S4: Independently regulate the reflection phases of the four polarization channels using the cross-polarization reflection phase and rotation angle of the unit.

[0095] Specifically, according to the phase addition operation:

[0096]

[0097] where, represents the total phase distribution, represents the phase distribution of the q-th channel, is the compensation phase. Then the total phase of the left-handed circularly polarized wave component in the total reflected field is:

[0098]

[0099] The total phase of the right-handed circularly polarized wave component is:

[0100]

[0101] Since the unit in this embodiment has achieved independent regulation of the left-handed circularly polarized wave and the right-handed circularly polarized wave, the four reflection channels can be independently regulated by the cross-polarization reflection phase and the unit rotation angle of the unit:

[0102]

[0103] In this embodiment, the designed metasurface is composed of 19*19 units. According to the calculation, the cross-polarization phase and rotation angle required for each unit at each position are found. The unit closest to the required phase is found among the 18 designed units, and after rotation, it is arranged on the metasurface. The cross-polarization phase distribution of the units on the metasurface is as Figure 3As shown, the arrangement of the metasurface is carried out in the CST electromagnetic simulation software, and the overall metasurface obtained is as Figure 4 shown.

[0104] In this embodiment, the parameters of the CST electromagnetic simulation software are set. The working frequency band is 8 - 16 GHz, the boundary condition is oppen (add space), a far - field monitor is added every 0.5 GHz, the incident wave is set as an x - polarized wave, vertically incident on the metasurface, the time - domain solver is used for simulation, and the far - field reflection pattern is plotted. The far - field pattern at the center frequency of 12 GHz is as Figure 5 shown.

[0105] In this embodiment, the far - field results of the reflected waves of the four channels are respectively viewed. The deflection angle of the reflected wave of the x - polarized channel is 10.45°, the deflection angle of the reflected wave of the y - polarized channel is 12.08°, the deflection angle of the reflected wave of the right - hand circularly polarized channel is 15.56°, and the deflection angle of the reflected wave of the left - hand circularly polarized channel is 17.65°. The pattern in the xoz plane is as Figure 6 shown, and the pattern in the yoz plane is as Figure 7 shown. It can be seen that it is consistent with the theoretical design. The metasurface realizes the independent control of the reflected waves of the four different polarization channels, and the side - lobe level drops by more than 10 dB compared with the main - lobe level, effectively suppressing the interference of the side - lobes.

[0106] In this embodiment, the designed metasurface has good broadband performance. The far - field pattern is viewed every 0.5 GHz within the working frequency band, and the plot of the beam deflection angles of different channels changing with frequency is as Figure 8 shown. It can be known that within the working frequency band, the metasurface can independently control the beam directions of the four channels, and the errors do not exceed 1°, having good broadband performance.

[0107] The above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any replacement made by those skilled in the art within the technical scope shown in this application without creative efforts should be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claims.

Claims

1. A broadband multi-polarized multi-beam independently controllable reflective metasurface, characterized in that A two-dimensional array is composed of multiple metasurface units. Each metasurface unit is based on a diagonally symmetric "I"-type metasurface unit. By calculating the cross-polarization reflection phase and unit rotation angle required for each unit position, independent control of x-polarized waves, y-polarized waves, left-handed circularly polarized waves, and right-handed circularly polarized waves is achieved. For the diagonally symmetric "I"-type metasurface unit, by changing the size parameters, the cross-polarization reflectivity at the center frequency is guaranteed to be above a set threshold, and the cross-polarization reflection phase uniformly covers the full range.

2. The reflective metasurface with independent broadband multi-polarization multi-beam control according to claim 1, wherein Cross-polarization reflection phase of the unit and the unit rotation angle θ, and the phase distribution relationship with the four reflection channels is where, mn represents the position of the mn-th unit, and represent the phase distributions of the x-polarized wave, y-polarized wave, left-handed circularly polarized wave, and right-handed circularly polarized wave respectively, j represents the imaginary unit, and arg represents the argument function.

3. A reflective metasurface with broadband multi-polarization and multi-beam independent regulation according to claim 1, characterized in that The "I"-type metasurface unit is formed by etching an "I"-type structured metal patch on a dielectric substrate with a metal backplane. The patch consists of two radius edges and two arc edges. When designing the diagonally symmetric "I"-type metasurface unit, first design the unit so that the phase covers 0 - 180°, and then rotate the designed unit by 90° respectively so that the phase covers 0 - 360°.

4. The reflective metasurface with independent regulation of broadband multi-polarization and multi-beams according to claim 3, characterized in that, The period of the metasurface unit is 0.27 - 0.29λ, the thickness of the substrate dielectric is 0.132 - 0.148λ, the material is F4B board, the radius of the "I"-type structured metal patch is 0.112λ - 0.0896λ, the width of the radius edge is 0.016λ - 0.018λ, the opening angle of the arc edge is 80° - 160°, and the width is 0.0216λ - 0.024λ, where λ is the operating wavelength.

5. A design method for a broadband multi-polarization multi-beam independently controllable reflective metasurface, which is used for a broadband multi-polarization multi-beam independently controllable reflective metasurface according to any one of claims 1-4, characterized in that, It includes the steps: Step S1, independently control the left-handed circularly polarized wave and the right-handed circularly polarized wave according to the cross-polarization reflection phase and rotation angle of the unit; Step S2, calculate the phase distribution of the beam in the target direction respectively according to the generalized Snell's law; Step S3, represent the total reflected field as the superposition of the left-handed circularly polarized wave and the right-handed circularly polarized wave; Step S4, independently control the reflection phases of the four polarization channels with the cross-polarization reflection phase and rotation angle of the unit.

6. The design method of a broadband multi-polarized multi-beam independently controllable reflective metasurface according to claim 5, characterized in that In the said step S1, it specifically includes: Step S11, for the diagonally symmetric unit, the diagonal terms of the Jones matrix become 0, and the Jones matrix is simplified to Among them, is the unit cross-polarization reflection phase; Step S12, introduce the unit rotation angle θ. For the rotated unit, its Jones matrix is expressed as When an x-polarized wave is incident, the reflected field is expressed as The first term is the left-handed circularly polarized wave, and the second term is the right-handed circularly polarized wave, then Among them, is the phase of the left-handed circularly polarized wave, is the phase of the right-handed circularly polarized wave. By adjusting the cross-polarization reflection phase and the unit rotation angle θ, independent control of the left-handed circularly polarized wave and the right-handed circularly polarized wave can be achieved.

7. The design method of a broadband multi-polarization multi-beam independently controllable reflective metasurface according to claim 5, characterized in that, In the step S2, the designed target reflected wave deflection phase is that the x-polarized wave deflects by θ in the -x direction x , the y-polarized wave deflects by θ in the -y direction y , the right-handed circularly polarized wave deflects by θ in the x direction R , the left-handed circularly polarized wave deflects by θ in the y direction L ; According to the generalized Snell's law at normal incidence: where θ r is the exit angle, n r is the refractive index of the exit medium, λ0 is the working wavelength, dφ is the phase difference between adjacent units, dx is the unit period, and the phases required for each of the four reflection channels can be designed as Among them, is the phase of the x-polarized wave, is the phase of the y-polarized wave, is the phase of the right-handed circularly polarized wave, is the phase of the left-handed circularly polarized wave.

8. The design method of a broadband multi-polarized multi-beam independently controllable reflective metasurface according to claim 5, characterized in that, In step S3, when an incident x-polarized wave is involved, the total reflection field E of any single metasurface unit mn can be regarded as the superposition of the reflection fields in each polarization channel: Among them, are the reflected fields of the x-polarization, y-polarization, right-hand circular polarization, and left-hand circular polarization channels respectively; Using the circular polarization basis to represent the linearly polarized wave, we can get: Among them, mn represents the position of the mn-th unit, E x 、E y 、E r 、E l respectively represent the amplitude values of the x-polarized, y-polarized, right-handed circularly polarized, and left-handed circularly polarized waves. The total reflected field is composed of the superposition of three left-handed circularly polarized waves and three right-handed circularly polarized waves.

9. The design method of a broadband multi-polarization multi-beam independently controllable reflective metasurface according to claim 5, characterized in that, In the said step S4, according to the phase addition operation: Among them, represents the total phase distribution, represents the phase distribution of the q-th channel, and N is the number of channels. is the compensation phase, then the total phase of the left-handed circularly polarized wave component in the total reflected field is The total phase of the right-handed circularly polarized wave component is Since the unit has achieved independent regulation of left-handed circularly polarized waves and right-handed circularly polarized waves, the four reflection channels can be independently regulated by the cross-polarization reflection phase of the unit and the rotation angle θ of the unit, and the formula is 10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it realizes the steps of a design method of a broadband multi-polarization multi-beam independently controllable reflective metasurface according to any one of claims 5 - 9.

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