A design method for dual-frequency polarization and mode-multiplexing circularly polarized vortex wave antennas

Abstract

This application relates to a design method for a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna. Using only a single dielectric substrate, it offers advantages such as low profile, small size, and light weight. It can be manufactured using mature PCB processes, significantly reducing processing costs and facilitating engineering implementation. Through the design of the elements and array, co-rotational reflection is achieved. The resulting array exhibits polarization and mode-multiplexing characteristics compared to traditional co-aperture reflector arrays, overcoming the limitations of insufficient spectrum resources in traditional wireless communication. The designed antenna can generate vortex waves with different polarizations and mode numbers in different frequency bands, and the beam pointing and mode number can be arbitrarily adjusted, showing significant application potential in wireless communication, target detection, microwave imaging, and security encryption.

Description

Technical Field

[0001] This application relates to the field of antenna design, specifically to a design method for a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna. Background Technology

[0002] Vortex electromagnetic waves carrying orbital angular momentum (OAM) have attracted widespread attention and become a research hotspot in the fields of radio frequency, microwave, and antennas because they have been shown to increase channel capacity through multiplexing orthogonal modes. Currently, in the field of radio frequency and microwave, research on the application of vortex electromagnetic waves mainly focuses on three aspects: (1) Research on OAM-based mode multiplexing technology in wireless communication, which can achieve ultra-high channel capacity while reducing multipath interference. (2) Electromagnetic waves carrying different OAM modes have rich phase wavefront structures, showing great application potential in target detection and microwave imaging, especially in improving azimuth resolution. (3) Combining OAM-based information encryption with polarization multiplexing will further improve the security of information transmission. However, existing vortex wave antennas suffer from a lack of wireless communication spectrum resources and insufficient channel capacity. Summary of the Invention

[0003] To overcome at least one deficiency in the prior art, this application provides a design method for a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna.

[0004] Firstly, a design method for a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna is provided, including:

[0005] Obtain the unit phase required for each metasurface reflection unit to generate a left-hand circularly polarized beam, and the unit phase required for each metasurface reflection unit to generate a right-hand circularly polarized beam;

[0006] The rotation angle for geometric phase control of each metasurface reflective unit and the dynamic phase compensation of the metasurface reflective unit are determined based on the phase of the two units.

[0007] Based on the dynamic phase compensation of the metasurface reflective unit and the correspondence between dynamic phase compensation and side length, the side length of the hexagonal frame of the metal patch in the metasurface reflective unit is determined; the metal patch includes a hexagonal frame with an opening on one side, and a hexagonal patch is set at the center of the hexagonal frame.

[0008] Each metasurface reflective unit is rotated counterclockwise by the specified rotation angle;

[0009] All metasurface reflective elements are arranged in a rectangular or circular periodic pattern to form a rectangular or circular aperture reflective array. A dual-circular polarized feed source is placed in front of the reflective array in a positive feed manner, ultimately forming a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna.

[0010] In one embodiment, determining the rotation angle for geometric phase control of each metasurface reflecting unit and the dynamic phase compensation of the metasurface reflecting unit based on the phases of the two units includes:

[0011] Construct the following relation:

[0012]

[0013] in, The unit phase required for each metasurface reflecting unit to generate a right-hand circularly polarized beam. The unit phase required for each metasurface reflecting unit to generate a left-hand circularly polarized beam. For dynamic phase compensation of metasurface reflective units, The rotation angle;

[0014] The rotation angle is obtained by solving the relationship between the two element phases. Dynamic phase compensation of metasurface reflective units

[0015] In one embodiment, the metasurface reflective unit includes a dielectric plate and a ground plane, with an air layer between the dielectric plate and the ground plane; a metal patch is disposed on the dielectric plate.

[0016] In one embodiment, the dual-frequency polarization and mode-multiplexed circularly polarized vortex wave antenna operates in two frequency bands: 10.7-12.75 GHz with a center frequency of 11.725 GHz, and 12.75-18.1 GHz with a center frequency of 15.425 GHz.

[0017] In one embodiment, the dual-circular polarization feed source is a conical horn antenna, the feeding method is positive feed, and the polarization method is dual-circular polarization.

[0018] In one embodiment, the focal diameter ratio of the reflective array is set to 0.866, and the vertical distance between the phase center of the dual circularly polarized feed and the reflective array is set to 259.8 mm.

[0019] Secondly, a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna is provided, comprising: a feed source and multiple metasurface reflective elements, wherein the multiple metasurface reflective elements are arranged in a rectangular or circular periodic manner to form a reflective array of a rectangular aperture array or a circular aperture array; the feed source is a dual circularly polarized feed source, which is placed in front of the reflective array in a positive feed manner;

[0020] Each metasurface reflective unit includes a dielectric substrate and a ground plane, with an air layer between them; a metal patch is disposed on the dielectric substrate; the metal patch includes a hexagonal frame with an opening on one side, and a hexagonal patch is disposed at the center of the hexagonal frame.

[0021] In one embodiment, the antenna operates in two frequency bands: 10.7-12.75 GHz with a center frequency of 11.725 GHz, and 12.75-18.1 GHz with a center frequency of 15.425 GHz.

[0022] In one embodiment, the feed source is a conical horn antenna, the feeding method is positive feed, and the polarization method is dual circular polarization.

[0023] In one embodiment, the focal diameter ratio of the reflective array is set to 0.866, and the vertical distance between the phase center of the dual circularly polarized feed and the reflective array is set to 259.8 mm.

[0024] Compared with the prior art, this application has the following beneficial effects:

[0025] 1. The circularly polarized vortex wave antenna of this application uses only one dielectric substrate, which has the advantages of low profile, small size and light weight. It can adopt mature PCB manufacturing process, which greatly reduces the processing cost and facilitates engineering implementation.

[0026] 2. The circularly polarized vortex wave antenna of this application achieves co-rotational reflection through the design of the elements and array. The array formed has the characteristics of polarization multiplexing and mode multiplexing compared with the vortex waves generated by the traditional same-aperture reflection array, thus making up for the lack of spectrum resources in traditional wireless communication.

[0027] 3. The broadband circularly polarized vortex wave antenna of this application has an axial ratio bandwidth that can cover the downlink and uplink frequency bands of Ku-band satellite communication, and the peak gains of the downlink and uplink operating frequency bands are 24.32dB and 23.87dB, respectively. Attached Figure Description

[0028] This application can be better understood by referring to the description given below in conjunction with the accompanying drawings, which, together with the detailed description below, are incorporated in and form part of this specification. In the drawings:

[0029] Figure 1 A flowchart illustrating the design method of dual-frequency polarization and mode-multiplexed circularly polarized vortex wave antennas is shown.

[0030] Figure 2 A schematic diagram of the principle of polarization multiplexing of metasurface reflective units is shown;

[0031] Figure 3A schematic diagram of a metasurface reflective unit is shown, wherein (a) is a 3-D view of the metasurface reflective unit, (b) is a top view of the metasurface reflective unit, and (c) is a diagram of the original position of the metasurface reflective unit.

[0032] Figure 4 A schematic diagram of the dynamic phase simulation results for each unit is shown; where (a) is the polarization reflection amplitude, (b) is the cross-polarization reflection amplitude, and (c) is the same polarization reflection phase.

[0033] Figure 5 A dynamic phase simulation diagram of a metasurface reflective unit without hexagonal patches is shown.

[0034] Figure 6 The diagram shows the simulation results of the geometric phase of each unit; where (a) is the simulation result of the geometric phase of the unit at 10.7 GHz, (b) is the simulation result of the geometric phase of the unit at 15 GHz, and (c) is the simulation result of the geometric phase of the unit at 18.1 GHz.

[0035] Figure 7 A schematic diagram of the three-dimensional structure of a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna is shown.

[0036] Figure 8 A top view of a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna is shown.

[0037] Figure 9 A schematic diagram of the amplitude and phase distribution of the near-field electric field of the vortex wave is shown, where (a) is the phase diagram at 11.725 GHz, (b) is the amplitude diagram at 11.725 GHz, (c) is the phase diagram at 15.425 GHz, and (d) is the amplitude diagram at 15.425 GHz.

[0038] Figure 10 The far-field gain pattern of the antenna is shown, where (a) is the gain pattern of the left-hand circularly polarized input at each frequency, and (b) is the gain pattern of the right-hand circularly polarized input at each frequency.

[0039] Figure 11 The antenna axial ratio radiation patterns are shown, where (a) is the axial ratio radiation pattern at each frequency of the left-hand circular polarization input, and (b) is the axial ratio radiation pattern at each frequency of the right-hand circular polarization input. Detailed Implementation

[0040] Exemplary embodiments of the present application will be described below with reference to the accompanying drawings. For clarity and brevity, not all features of the actual embodiments are described in the specification. However, it should be understood that many embodiment-specific decisions can be made in the development of any such actual embodiment to achieve the developer’s specific objectives, and these decisions may vary as the embodiments differ.

[0041] It should also be noted that, in order to avoid obscuring this application with unnecessary details, only the device structure closely related to the solution according to this application is shown in the accompanying drawings, while other details that are not closely related to this application are omitted.

[0042] It should be understood that this application is not limited to the described embodiments by virtue of the following description with reference to the accompanying drawings. In this document, embodiments may be combined with each other, features may be substituted or borrowed between different embodiments, and one or more features may be omitted in one embodiment, where feasible.

[0043] This application provides a design method for a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna. Figure 1 A flowchart illustrating the design method for dual-frequency polarization and mode-multiplexed circularly polarized vortex wave antennas is shown. (See attached image.) Figure 1 It mainly includes the following steps:

[0044] Step S1: Obtain the unit phase required for each metasurface reflection unit to generate a left-hand circularly polarized beam, and the unit phase required for each metasurface reflection unit to generate a right-hand circularly polarized beam.

[0045] Step S2: Determine the rotation angle for geometric phase control of each metasurface reflective unit and the dynamic phase compensation of the metasurface reflective unit based on the phases of the two units.

[0046] Figure 2 A schematic diagram of the polarization multiplexing principle of metasurface reflective units is shown. Combined with dynamic phase and geometric phase modulation, independent control of beams with different polarizations can be achieved. Geometric phase modulation can be achieved by rotating the unit; the rotation angle is... So, what is the unit phase required for each metasurface reflection unit to generate a left-handed circularly polarized beam? And the unit phase required for each metasurface reflecting unit to generate a right-hand circularly polarized beam. It has the opposite effect.

[0047] When the gradient changes linearly, the left-hand and right-hand circularly polarized reflected waves point in opposite directions and are symmetrical about the reflector's normal. Dynamic phase compensation is achieved by adjusting the total length of the sides of the open hexagonal ring. If the reflection array is composed of isotropic elements, it will provide the same phase compensation for both left-hand and right-hand circularly polarized reflected waves.

[0048] By combining dynamic phase and geometric phase, right-hand circular polarization (RHCP) and left-hand circular polarization (LHCP) can be adjusted independently to achieve dual circular polarization multiplexing.

[0049] Specifically, construct the following relation:

[0050]

[0051] in, The unit phase required for each metasurface reflecting unit to generate a right-hand circularly polarized beam. The unit phase required for each metasurface reflecting unit to generate a left-hand circularly polarized beam. For dynamic phase compensation of metasurface reflective units, The rotation angle;

[0052] The rotation angle is obtained by solving the relationship between the two element phases. Dynamic phase compensation of metasurface reflective units

[0053] Step S3: Based on the dynamic phase compensation of the metasurface reflective unit and the correspondence between dynamic phase compensation and side length, determine the side length of the hexagonal frame of the metal patch in the metasurface reflective unit. The metal patch includes a hexagonal frame with an opening on one side, and a hexagonal patch is placed at the center of the hexagonal frame. Table 1 shows the correspondence between dynamic phase compensation and side length. It should be noted that the dynamic phase of the unit also changes with a gradient, but for simplicity, the dynamic phase of 360° is represented discretely here. Starting from 0°, the dynamic phase of 360° can be obtained by increasing the gradient by 10°. Among them, 0-170° can be divided into 18 units of state 1, and 180°-350° can be divided into 18 units of state 2. The 18 units of state 1 are represented as No.1-No.18 in Table 1, and the 18 units of state 2 are represented as No.19-No.36 in Table 1. The intervals between No.1-No.18 and No.19-No.36 are simply a 90° rotation of the elements, and all the parameters of these elements are exactly the same. Since element rotation does not change its dynamic phase characteristics, for the sake of simplicity, the dynamic phase analysis will only focus on the characteristics of these 18 elements (No.1-No.18) in state 1.

[0054] The side length of the hexagonal frame can be obtained by looking up Table 1 based on the dynamic phase compensation (DP / °).

[0055] Figure 3 A schematic diagram of a metasurface reflective unit is shown, wherein (a) is a 3-D view of the metasurface reflective unit, (b) is a top view of the metasurface reflective unit, and (c) is a diagram of the original position of the metasurface reflective unit.

[0056] The side length l of the hexagonal border is (3l1 / 2 + l2 + l3) * 2, where l1, l2, and l3 are all side lengths of the hexagonal border. Figure 3 As shown in (b).

[0057] Table 1

[0058]

[0059] Here, the hexagonal patch can compensate for the frequency shift caused by the change in the total length of the hexagonal border. The introduction of the hexagonal patch can widen the cell's operating bandwidth, thereby enabling the cell's -10dB cross-polarization bandwidth to cover the downlink and uplink frequencies of Ku-band satellite communication. Figure 4 The diagram shows the simulation results of the dynamic phase of each unit, where (a) is the polarization reflection amplitude, (b) is the cross-polarization reflection amplitude, and (c) is the same polarization reflection phase; (a), (b), and (c) each include three figures, which, from left to right, show the dynamic phase characteristics of 18 units in three groups: No.1-No.6, No.7-No.12, and No.13-No.18 in state 1.

[0060] Figure 5 The simulation diagram of the dynamic phase of the metasurface reflective element without the hexagonal patch is shown, including three figures. From left to right, they represent the dynamic phase characteristics of 18 elements in three groups: No.1-No.6, No.7-No.12, and No.13-No.18 in state 1. It should be noted that... Figure 5 and Figure 4 All 18 elements are identical except for the removal of the hexagonal patch; the other element parameters are exactly the same as those with the hexagonal patch.

[0061] Figure 6 The diagram shows the simulation results of the geometric phase of each unit. (a) shows the simulation results at 10.7 GHz, (b) shows the simulation results at 15 GHz, and (c) shows the simulation results at 18.1 GHz. Each of (a), (b), and (c) includes three figures, from left to right, representing the geometric phase simulation results for No. 1, 4, 7, 10, 13, 16, No. 2, 5, 8, 11, 14, 17, and No. 3, 6, 9, 12, 15, 18 in State 1.

[0062] according to Figure 5 It can be seen that without the hexagonal patch, the -10dB cross-polarization bandwidth of the cell is 11.7-14.5GHz (21.3%). Figure 4 As can be seen from (b), the -10dB cross-polarization bandwidth of the cell with the hexagonal patch is 10.6-18.2 GHz (52.7%). In comparison, the -10dB cross-polarization bandwidth of the cell is widened by 31.4% when the hexagonal patch is used.

[0063] Step S4: Rotate each metasurface reflective unit counterclockwise by the specified rotation angle. Here, the metasurface reflective unit is composed of... Figure 3 The original position shown in (c) is rotated counterclockwise by the rotation angle obtained in step S2, thereby achieving the control of the geometric phase.

[0064] In step S5, all metasurface reflective elements are arranged in a rectangular or circular periodic pattern to form a rectangular aperture array or a circular aperture array reflective array. A dual circularly polarized feed source is placed in front of the reflective array in a positive feed manner, ultimately forming a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna. Figure 7 A schematic diagram of the three-dimensional structure of a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna is shown. Figure 8 A top view of a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna is shown.

[0065] Here, 1600 metasurface reflective units can be set, with an array aperture D = 300 mm.

[0066] In one embodiment, see Figure 2 The metasurface reflective unit includes a dielectric substrate and a ground plane, with an air layer between them; a metal patch is placed on the dielectric substrate.

[0067] Specifically, the thickness of the air layer is 1.6 mm, meaning that the floor 6 is located 1.6 mm below the dielectric plate 4. The fixed parameters of the metasurface reflective unit are: the side length of the dielectric plate d = 7.5 mm, the thickness of the dielectric plate h1 = 1.5 mm, and the thickness of the air layer h2 = 1.6 mm.

[0068] Furthermore, the dual-frequency polarization and mode-multiplexed circularly polarized vortex wave antenna operates in two frequency bands: 10.7-12.75 GHz with a center frequency of 11.725 GHz, and 12.75-18.1 GHz with a center frequency of 15.425 GHz. These two frequency bands correspond to the downlink and uplink bands in Ku-band satellite communication, respectively.

[0069] Furthermore, the dual-circular polarization feed source is a conical horn antenna, the feeding method is positive feed, and the polarization method is dual-circular polarization.

[0070] Furthermore, in order to ensure the radiation efficiency of the reflector array, the illumination level of the feed at the edge of the array needs to be reduced by 10-15dB. Therefore, the focal diameter ratio of the reflector array is set to 0.866, that is, the vertical distance between the phase center of the dual circularly polarized feed and the reflector array is set to 259.8mm.

[0071] This application embodiment also provides a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna, including: a feed source and multiple metasurface reflective elements, the multiple metasurface reflective elements being arranged in a rectangular or circular periodic manner to form a reflective array of a rectangular aperture array or a circular aperture array; the feed source is a dual circularly polarized feed source, placed in front of the reflective array in a positive feed manner;

[0072] Each metasurface reflective unit includes a dielectric substrate and a ground plane, with an air layer between them; a metal patch is disposed on the dielectric substrate; the metal patch includes a hexagonal frame with an opening on one side, and a hexagonal patch is disposed at the center of the hexagonal frame.

[0073] Specifically, the antenna operates in two frequency bands: 10.7-12.75GHz with a center frequency of 11.725GHz, and 12.75-18.1GHz with a center frequency of 15.425GHz.

[0074] Specifically, the feed source is a conical horn antenna, the feeding method is positive feed, and the polarization method is dual circular polarization.

[0075] Specifically, the focal diameter ratio of the reflective array is set to 0.866, and the vertical distance between the phase center of the dual circularly polarized feed and the reflective array is set to 259.8 mm.

[0076] The specific implementation method of this embodiment can be found in the previous embodiment section, and its technical effect corresponds to the technical effect of the above method, so it will not be repeated here.

[0077] To further verify the effectiveness of the method in this application, the following experiments were conducted.

[0078] In this embodiment of the invention, the array size is selected as 300mm × 300mm, and the focal diameter ratio is 0.866. When a left-handed circularly polarized wave is incident, it can generate a vortex wave with a mode number of -1, and the beam direction is θ = 3°. When a right-hand circularly polarized wave is incident, it can generate a vortex wave with a mode number of +2, and the beam direction is θ = -5°. After determining the phase to be compensated for each unit using the above formula, the specific dimensions and rotation angles of each unit are determined by combining the dynamic phase and geometric phase, and modeling and simulation are performed using MATLAB in conjunction with full-wave simulation software.

[0079] Figure 9 A schematic diagram of the amplitude and phase distribution of the near-field electric field of the vortex wave is shown, where (a) is the phase diagram at 11.725 GHz, (b) is the amplitude diagram at 11.725 GHz, (c) is the phase diagram at 15.425 GHz, and (d) is the amplitude diagram at 15.425 GHz. The distance between the observation plane and the array for this phase and amplitude is 400 mm, and the size of the observation plane is 300 × 300 mm. 2When a left-handed circularly polarized wave is incident, the phase distribution of the electric field changes by -360° within one revolution, exhibiting a spiral arm and a characteristic of l = -1. When a right-handed circularly polarized wave is incident, the phase distribution of the electric field changes by 720° within one revolution, exhibiting a spiral arm and a characteristic of l = +2. The electric field amplitude has a zero point at the center, causing its amplitude distribution to exhibit a "donut" shape, consistent with the characteristic that the energy at the center of a vortex electromagnetic wave beam is zero.

[0080] Figure 10 The far-field gain pattern of the antenna is shown, where (a) is the gain pattern of the left-hand circularly polarized input at each frequency, and (b) is the gain pattern of the right-hand circularly polarized input at each frequency. Figure 11 The antenna axial ratio patterns are shown, where (a) is the axial ratio pattern at each frequency of the left-hand circularly polarized input, and (b) is the axial ratio pattern at each frequency of the right-hand circularly polarized input. It can be seen from the figures that when a left-hand circularly polarized wave is incident, the beam direction is θ = 3°. The radiation pattern shows a radiation hole at the center, and the axial ratios near the main lobe are all less than 3 dB, indicating that the metasurface reflector array generated left-handed circularly polarized vortex waves in the 10.7-12.75 GHz frequency band, and that these waves could be reflected in the same direction of rotation, with a peak gain of 24.32 dB within the band. When a right-handed circularly polarized wave is incident, the beam direction is θ = -5°. The radiation hole is visible at the center of the radiation pattern, and the axial ratio near the main lobe is less than 3dB, indicating that the metasurface reflector array generated right-hand circularly polarized vortex waves in the 12.75-18.1GHz frequency band and can reflect in the same direction of rotation. The peak gain in the frequency band is 23.87dB.

[0081] In summary, this application proposes a broadband low-Q reflective metasurface element with polarization conversion capability. This element can achieve co-rotational reflection of circularly polarized waves and can independently control two beams with different polarizations by combining dynamic phase and geometric phase. An array based on this metasurface element generated left-handed circularly polarized vortex waves in the 10.7-12.75 GHz frequency band with a peak gain of 24.32 dB. It also generated right-handed circularly polarized vortex waves in the 12.75-18.1 GHz frequency band with a peak gain of 23.87 dB. This technology has significant application prospects in the field of communications and lays the technical foundation for the practical development of dual-frequency polarization multiplexing and mode-multiplexed vortex wave antennas.

[0082] The above descriptions are merely various embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A design method for a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna, characterized in that, include: Obtain the unit phase required for each metasurface reflection unit to generate a left-hand circularly polarized beam, and the unit phase required for each metasurface reflection unit to generate a right-hand circularly polarized beam; The rotation angle for geometric phase control of each metasurface reflective unit and the dynamic phase compensation of the metasurface reflective unit are determined based on the phase of the two units. Based on the dynamic phase compensation of the metasurface reflective unit and the correspondence between dynamic phase compensation and side length, the side length of the hexagonal frame of the metal patch in the metasurface reflective unit is determined; the metal patch includes a hexagonal frame with an opening on one side, and a hexagonal patch is disposed at the center of the hexagonal frame. Each metasurface reflective unit is rotated counterclockwise by the specified rotation angle; All metasurface reflective elements are arranged in a rectangular or circular periodic pattern to form a rectangular or circular aperture reflective array. A dual-circular polarized feed source is placed in front of the reflective array in a positive feed manner, ultimately forming a dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna.

2. The method as described in claim 1, characterized in that, in, The rotation angle for geometric phase control of each metasurface reflecting unit is determined based on the phases of the two units, and the dynamic phase compensation of the metasurface reflecting unit includes: Construct the following relation: ， in, The unit phase required for each metasurface reflecting unit to generate a right-hand circularly polarized beam. The unit phase required for each metasurface reflecting unit to generate a left-hand circularly polarized beam. For dynamic phase compensation of metasurface reflective units, The rotation angle; The rotation angle is obtained by solving the relationship based on the phases of the two units. Dynamic phase compensation of metasurface reflective units .

3. The method as described in claim 1, characterized in that, The metasurface reflective unit includes a dielectric plate and a ground plane, with an air layer between the dielectric plate and the ground plane; the metal patch is disposed on the dielectric plate.

4. The method as described in claim 1, characterized in that, The dual-frequency polarization and mode-multiplexed circularly polarized vortex wave antenna operates in two frequency bands: 10.7-12.75GHz with a center frequency of 11.725GHz, and 12.75-18.1GHz with a center frequency of 15.425GHz.

5. The method as described in claim 1, characterized in that, The dual-circular polarization feed source is a conical horn antenna, with positive feed and dual-circular polarization.

6. The method as described in claim 1, characterized in that, The focal diameter ratio of the reflective array is set to 0.866, and the vertical distance between the phase center of the dual circularly polarized feed and the reflective array is set to 259.8 mm.

7. A dual-frequency polarized and mode-multiplexed circularly polarized vortex wave antenna, characterized in that, include: The feed source and multiple metasurface reflective units are arranged in a rectangular or circular periodic pattern to form a reflective array with a rectangular aperture array or a circular aperture array. The feed source is a dual circular polarization feed source, which is placed in front of the reflective array in a positive feed manner; Each metasurface reflective unit includes a dielectric plate and a ground plane, with an air layer between the dielectric plate and the ground plane; a metal patch is disposed on the dielectric plate; the metal patch includes a hexagonal frame with an opening on one side, and a hexagonal patch is disposed at the center of the hexagonal frame; The dual-frequency polarization and mode-multiplexed circularly polarized vortex wave antenna is obtained by the design method of the dual-frequency polarization and mode-multiplexed circularly polarized vortex wave antenna according to claim 1 or 2.

8. The antenna as claimed in claim 7, characterized in that, The antenna operates in two frequency bands: 10.7-12.75GHz with a center frequency of 11.725GHz, and 12.75-18.1GHz with a center frequency of 15.425GHz.

9. The antenna as claimed in claim 7, characterized in that, The feed source is a conical horn antenna, with positive feeding and dual circular polarization.

10. The antenna as claimed in claim 7, characterized in that, The focal diameter ratio of the reflective array is set to 0.866, and the vertical distance between the phase center of the dual circularly polarized feed and the reflective array is set to 259.8 mm.

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