An antenna for implementing quasi-non-diffracting beamforming and scanning

Abstract

The application relates to an antenna for realizing quasi-non-diffracting beam shaping and scanning, which comprises a phase shift super surface and a feed horn antenna, and the feed horn antenna is opposite to the center of the phase shift super surface; the phase shift super surface is a double-layer dielectric substrate structure with an electromagnetic wave phase shift function, and the whole phase shift super surface is composed of a plurality of periodically arranged phase shift units; the structure of each phase shift unit comprises upper, middle and lower three layers of metal patches and upper and lower layers of dielectric substrates; the phase shift unit is equivalent to a low-pass filter phase shifter with a phase shift effect; by setting the size of the three layers of metal patches in each phase shift unit on the phase shift super surface, different angle insertion phase shifts can be realized at any position of the phase shift super surface; and then under the irradiation of the feed horn antenna, a phase distribution meeting the ideal phase shift quantity of the quasi-non-diffracting beam can be generated on the outlet surface of the phase shift super surface, so as to generate the quasi-non-diffracting beam. The application solves the uncontrollable problem of the starting point of the non-diffracting area of the quasi-non-diffracting beam.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of electromagnetic beam forming, in particular to an antenna for realizing quasi-non-diffracting beam shaping and scanning. BACKGROUND

[0002] Bessel beams have the characteristics of beam propagation, and can propagate for a considerable distance in a non-diffracting manner. Spatially focused propagation of electromagnetic waves has very important applications, and is required in the fields of wireless transmission of electromagnetic energy, THz frequency band spatial waveguide, near-field detection radar, microwave medical instruments, high-precision microwave measurement, and even space solar energy ground-to-space transmission.

[0003] Quasi-non-diffracting beams have been extensively and deeply studied in the fields of optics and electromagnetic waves. Quasi-non-diffracting beams can be generated through an axicon lens, a dielectric integrated waveguide, a leaky wave antenna, etc. However, the starting point of the non-diffracting region of the existing quasi-non-diffracting beam antenna is from the beam generating device, and the starting point of the non-diffracting region of the quasi-non-diffracting beam cannot be controlled arbitrarily, which greatly limits the application scenarios of the quasi-non-diffracting beam. Therefore, it is of great significance to design a new quasi-non-diffracting beam generating device with a simple structure and a controllable non-diffracting region of the quasi-non-diffracting beam.

[0004] It should be noted that the information disclosed in the above background section is only used to strengthen the understanding of the background of the present application, and therefore can include information that does not constitute prior art known to those of ordinary skill in the art. SUMMARY

[0005] The present application provides an antenna for realizing quasi-non-diffracting beam shaping and scanning, which solves the problems of uncontrollable starting point of the non-diffracting region of the quasi-non-diffracting beam, complex structure, and high processing cost.

[0006] Other characteristics and advantages of the present application will become apparent from the following detailed description, or will be learned by practice of the present application.

[0007] According to a first aspect of the present application, an antenna for realizing quasi-non-diffracting beam shaping and scanning is provided, comprising a phase shift super surface and a feed horn antenna, the feed horn antenna facing the center of the phase shift super surface; the phase shift super surface is a double-layer dielectric substrate structure with electromagnetic wave phase shift function, comprising a printed circuit upper layer, a dielectric substrate upper layer, a printed circuit middle layer, a dielectric substrate lower layer, and a printed circuit lower layer stacked coaxially from top to bottom, the entire phase shift super surface is composed of a plurality of periodically arranged phase shift units, the structure of each phase shift unit comprises upper, middle and lower metal patches and upper and lower dielectric substrates;

[0008] The phase shift unit is equivalent to a low-pass filter phase shifter with a phase shift effect. By setting the size of the three layers of metal patches in each phase shift unit on the phase shift super surface, an insertion phase shift of 0 degrees, -90 degrees, -180 degrees, and -270 degrees can be achieved at any position on the phase shift super surface. Then, under the irradiation of the feed horn antenna, a phase distribution satisfying the ideal phase shift amount of the quasi-non-diffractive beam is generated on the exit surface of the phase shift super surface to generate the quasi-non-diffractive beam.

[0009] In some example embodiments, the ideal phase shift amount of each phase shift unit of the phase shift super surface From formulas (1)-(7), it can be obtained that:

[0010] (1)

[0011] (2)

[0012] (3)

[0013] (4)

[0014] (5)

[0015] (6)

[0016] (7)

[0017] wherein, is the working frequency of the antenna, c is the speed of light in free space, and is the coordinate of the center point of each phase shift unit, F is the distance from the phase center of the feed horn antenna to the phase shift super surface, R is the radius of the phase shift super surface, p is the distance from each phase shift unit to the center of the phase shift super surface, θ is the included angle between the beam direction and the phase shift super surface, and z 1 is used to control the depth of field of the quasi-non-diffractive beam and the starting point of the quasi-non-diffractive area, respectively.

[0018] In some example embodiments, the phase shift unit is rectangular or hexagonal; when it is rectangular, the phase shift unit is arranged in a square needle shape, and when it is hexagonal, the phase shift unit is arranged in a honeycomb shape.

[0019] In some example embodiments, the size of the metal patch in the phase shift unit corresponding to different phase shift amplitudes is obtained in full-wave simulation software through periodic boundary conditions.

[0020] In some example embodiments, the feed horn antenna is a linearly polarized, circularly polarized or multi-polarized horn antenna.

[0021] In some example embodiments, in each phase shift unit, the size of the lower metal patch of the printed circuit and the upper metal patch of the printed circuit is the same.

[0022] According to a second aspect of the present application, a design method of an antenna for quasi-non-diffracting beamforming and scanning is provided, a corresponding phase shift unit is selected according to a phase shift amount, a phase shift metasurface is arranged, a desired quasi-non-diffracting beam is generated according to a generated phase distribution, and the phase shift amount is changed in the design 、 and different quasi-non-diffracting beams with different directions and different areas are realized; the design method comprises the following steps:

[0023] The size of the metal patch in the phase shift unit corresponding to different phase shift amounts is obtained by simulation in a full-wave simulation software through a periodic boundary condition;

[0024] According to the position of each phase shift unit, the ideal phase shift amount of the phase shift unit is calculated according to formulas (1)-(7);

[0025] The actual phase shift amount is calculated based on the ideal phase shift amount;

[0026] The size of the metal patch corresponding to the phase shift unit at different positions is selected based on the actual phase shift amount.

[0027] In some example embodiments, the actual phase shift amount is calculated based on the ideal phase shift amount by using the following formula:

[0028] 90°

[0029] wherein, int is a floor function, is the ideal phase shift amount, is the actual phase shift amount.

[0030] The antenna for quasi-non-diffracting beamforming and scanning provided by the embodiments of the present application has the following advantages:

[0031] Firstly, the present application adopts the phase shift metasurface technology and only uses the ordinary PCB process, and the phase shift metasurface is only about 1 millimeter thick;

[0032] Secondly, the starting point of the quasi-non-diffracting region of the quasi-non-diffracting beam can be freely set.

[0033] Third, in terms of implementation effect, since the phase shift super surface is extremely thin, the dielectric loss can be almost ignored;

[0034] Fourth, the mature PCB process can realize higher processing precision, and is a low-cost solution suitable for mass production, and has unique advantages for realizing quasi-non-diffraction beams of microwaves, especially millimeter wave bands;

[0035] Fifth, compared with various quasi-non-diffraction beam antennas under the method of aperture synthesis, the structure is simpler, without complex feeding structure, and transmission and mismatch loss are avoided.

[0036] Sixth, compared with the existing technologies such as axicon lenses, leaky-wave antennas and dielectric integrated waveguides, the beamforming plane of the application has simple structure, low cost and is easy to process.

[0037] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, and cannot limit the application. BRIEF DESCRIPTION OF DRAWINGS

[0038] The drawings incorporated into the specification and forming part of the specification, show embodiments consistent with the application, and together with the specification, serve to explain the principles of the application. Obviously, the drawings in the following description are only some embodiments of the application, and other drawings can be obtained from these drawings without creative labor for those skilled in the art.

[0039] Figure 1 is a side view schematic diagram of the antenna of the application;

[0040] Figure 2 is a side view schematic diagram of the phase shift super surface in embodiment 1 of the application;

[0041] Figure 3 is a schematic diagram of the phase shift unit distribution of the upper and lower layers of the phase shift super surface printed circuit in embodiment 1 of the application;

[0042] Figure 4 is a schematic diagram of the phase shift unit distribution of the middle layer of the phase shift super surface printed circuit in embodiment 1 of the application;

[0043] Figure 5 is a front view of the phase shift unit on the phase shift super surface of the application;

[0044] Figure 6 is a simulation diagram of the longitudinal and transverse cross-section of the quasi-non-diffraction beam electric field intensity in embodiment 1 of the application;

[0045] Figure 7is a comparison diagram of the axial electric field intensity of the quasi-non-diffracting wave beam generated by the present application and the axial electric field intensity of the quasi-non-diffracting wave beam with the starting point of the quasi-non-diffracting area fixed;

[0046] Wherein: 1 is the bunching plane, 2 is the feed horn antenna, 1 is the upper layer of the printed circuit, 21 is the upper layer of the high-frequency dielectric substrate, 12 is the middle layer of the printed circuit, 22 is the lower layer of the high-frequency dielectric substrate, 13 is the lower layer of the printed circuit, 111, 121 and 131 are metal patches arranged in the upper, middle and lower layers of the printed circuit respectively. DETAILED DESCRIPTION

[0047] Example implementations will now be described more fully with reference to the accompanying drawings. Example implementations may, however, be implemented in many different forms and should not be construed as limited to the examples set forth herein; rather, these implementations are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the example implementations to those skilled in the art. The described features, structures, or characteristics can be combined in any suitable manner in one or more implementations.

[0048] In addition, the accompanying drawings are included to provide a further understanding of the present application, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application. In the drawings:

[0049] In the related art, an antenna generating a Bessel wave beam has been disclosed, which can generate a Bessel wave beam with controllable depth of field by changing the phase distribution of the bunching plane. However, the antenna in this invention can only generate a Bessel wave beam perpendicular to the bunching plane, and the starting point of the non-diffraction area cannot be controlled and is always located on the bunching plane.

[0050] In the related art, an antenna generating a Bessel wave beam has been disclosed, which can generate a Bessel wave beam with controllable depth of field by changing the phase distribution of the bunching plane. However, the antenna in this invention can only generate a Bessel wave beam perpendicular to the bunching plane, and the starting point of the non-diffraction area cannot be controlled and is always located on the bunching plane.

[0051] A paper titled "Multitarget wireless power transfer system using metasurface for quasi-Bessel beams with large half power beam length" is also disclosed in the prior art, which proposes a wireless power transfer system. The phase distribution of the metasurface is calculated according to the desired quasi-Bessel beam, and the quasi-Bessel beam is generated by illuminating the metasurface with a horn antenna to wirelessly transfer power to multiple targets. However, the starting point of the quasi-Bessel beam generated by the method proposed in the paper is located on the metasurface, which has lower energy utilization compared to the quasi-non-diffractive beam with adjustable starting point.

[0052] A paper titled "Quasi-Nondiffractive Multibeam Antennas Based on Phase Shift Surfaces" is also disclosed in the prior art, which proposes a method for generating quasi-non-diffractive multi-beam. The method generates quasi-non-diffractive multi-beam by illuminating the phase shift surface with a horn antenna, each beam can be independently controlled, and the interference between each beam is reduced by introducing an optimized phase. However, the starting point of the quasi-non-diffractive multi-beam generated by this method is always located on the phase shift surface, and the starting point of the quasi-non-diffractive region of the quasi-non-diffractive beam cannot be controlled.

[0053] A beam direction adjustable non-diffractive phase shift super surface antenna is also disclosed in the prior art. The invention realizes a specific non-diffractive beam through the phase distribution on the phase shift super surface. Similarly, the antenna in the invention can only generate non-diffractive beams perpendicular to the phase shift super surface, and the starting point of the non-diffractive region cannot be controlled and is always located on the phase shift super surface.

[0054] In view of the shortcomings and deficiencies of the prior art, the present application provides an antenna for realizing quasi-non-diffractive beam shaping and scanning. In view of the problem that the starting point of the non-diffractive region of the quasi-non-diffractive beam cannot be controlled, the starting point of the non-diffractive region of the quasi-non-diffractive beam is controlled by adjusting the phase distribution of the focusing plane, and the structure is simple and the processing cost is low. The technical problems existing in the traditional non-diffractive beam antenna can be solved:

[0055] 1. With the extensive and in-depth research of quasi-non-diffractive beams in the field of optics and electromagnetic waves, quasi-non-diffractive beams are generated by technologies such as axicon lenses, dielectric integrated waveguides, and leaky wave antennas. However, the structure of axicon lenses, dielectric integrated waveguides, and leaky wave antennas is complex and the processing cost is high, so a quasi-non-diffractive beam antenna with simple structure and low processing cost is needed.

[0056] 2. Traditional quasi-diffraction-free beam antennas generate quasi-diffraction-free beams, and the starting point of the quasi-diffraction-free region always starts from the beam generating device. It is impossible to control the starting point of the diffraction-free region. For scenarios where the target diffraction-free range is located at a distance from the beam generating device, the energy utilization rate is low compared to quasi-diffraction-free beam antennas with controllable starting points, which greatly limits the practical application scenarios of quasi-diffraction-free beam antennas.

[0057] This invention provides a quasi-diffraction-free beam antenna that generates a quasi-diffraction-free region and has a controllable scanning angle. The antenna includes a phase-shifting metasurface and a fed horn antenna, with the fed horn antenna facing the center of the phase-shifting metasurface. The phase-shifting metasurface is a double-layer dielectric substrate structure with electromagnetic wave phase-shifting functionality. It comprises, from top to bottom, a coaxially stacked upper layer of printed circuitry, an upper layer of dielectric substrate, a middle layer of printed circuitry, a lower layer of dielectric substrate, and a lower layer of printed circuitry. The entire phase-shifting metasurface is composed of several periodically arranged phase-shifting units. Each phase-shifting unit includes upper, middle, and lower metal patches and upper and lower dielectric substrates.

[0058] Ideal phase shift amount per cell of phase-shifted metasurface From formulas (1) to (7), we can obtain:

[0059] (1)

[0060] (2)

[0061] (3)

[0062] (4)

[0063] (5)

[0064] (6)

[0065] (7)

[0066] in, f The operating frequency of the antenna. c The speed of light in free space. and Let the coordinates of the center point of each phase-shifting unit be... Let be the distance from the phase center of the fed horn antenna to the phase-shifted metasurface. Let be the radius of the phase-shifting metasurface. p The distance between each phase-shifting unit and the center of the phase-shifting metasurface. θ It is the angle between the beam direction and phase-shifting metasurface 1. and respectively used to control the depth of field of the quasi-non-diffracting beam and the starting point of the quasi-non-diffracting region, 、 、 、 、 and are intermediate variables. According to the positions of each phase shift unit, the phase shift amount of each phase shift unit is calculated according to the above formulas (1)-(7), the corresponding phase shift unit is selected according to the phase shift amount, the phase shift metasurface is laid out, the expected quasi-non-diffracting beam is generated according to the generated phase distribution, and 、 and different quasi-non-diffracting beams with different directions and different regions are realized.

[0067] The phase distribution of the phase shift metasurface designed in the application is derived according to the expected quasi-non-diffracting beam through formulas (1)-(7). The quasi-non-diffracting beam generated is different from the prior art in that the starting point of the quasi-non-diffracting region of the quasi-non-diffracting beam can be freely set as required, instead of being fixed on the beam generating device. The ideal phase shift amount calculated in the conventional quasi-non-diffracting beam only focuses on the angle between the beam direction and the phase shift metasurface and the depth of field of the quasi-non-diffracting beam, and the quasi-non-diffracting beam generated in the application not only focuses on the angle between the beam direction and the phase shift metasurface and the depth of field of the quasi-non-diffracting beam, but also focuses on the starting point of the quasi-non-diffracting region.

[0068] In the following, the structure of the antenna for realizing quasi-non-diffracting beam shaping and scanning in the example embodiment will be described in more detail in combination with the accompanying drawings and examples.

[0069] Example 1

[0070] As shown in Figure 1 , the present embodiment provides a quasi-non-diffracting beam antenna with controllable quasi-non-diffracting region and scanning angle, which comprises a phase shift metasurface 1 and a feed horn antenna 2, the feed horn antenna 2 is opposite to the center of the phase shift metasurface 1; the phase shift metasurface 1 converts the quasi-spherical wave emitted from the feed horn antenna 2 into a quasi-non-diffracting beam.

[0071] As shown in Figure 2 , the phase shift metasurface 1 is a double-layer dielectric substrate structure with electromagnetic wave phase shift function, which comprises a printed circuit upper layer 11, a dielectric substrate upper layer 21, a printed circuit middle layer 12, a dielectric substrate lower layer 22 and a printed circuit lower layer 13 which are coaxially stacked in sequence from top to bottom, the radius of the two layers of dielectric substrates is 215 mm, the thickness is 0.508 mm, and the relative dielectric constant is 2.2; the whole phase shift metasurface is composed of a plurality of periodically arranged phase shift units, the size of the printed circuit upper layer and the printed circuit lower layer is the same, as shown in Figure 3The shape of the middle layer of the printed circuit is a hexagonal structure, which is the same as the shapes of the upper layer and the lower layer of the printed circuit, as shown in Figure 4 The structure of each phase shift unit includes three layers of metal patches 111, 121, and 131, and upper and lower layers of dielectric substrates 211 and 221, as shown in Figure 5 By designing the side length of the three layers of metal patches of the phase shift unit, 0 degrees, -90 degrees, -180 degrees, and -270 degrees of insertion phase shift can be achieved.

[0072] In terms of working principle, the phase shift unit is equivalent to a low-pass filter phase shifter with a phase shift effect. By setting the size of the three layers of metal patches in each phase shift unit on the phase shift metasurface, 0 degrees, -90 degrees, -180 degrees, and -270 degrees of insertion phase shift can be achieved at any position on the phase shift metasurface. Then, under the irradiation of the feed horn antenna, a phase distribution that satisfies the ideal phase shift amount of the quasi-non-diffractive beam is generated on the exit surface of the phase shift metasurface to generate a quasi-non-diffractive beam.

[0073] In this example, the radius R of the phase shift metasurface 1 is 215 mm, the working frequency f is 29 GHz, the free space light speed c is 3 x 108m / s, the upper layer 21 and the lower layer 22 of the dielectric substrate are Taconic TLY-5 dielectric plates with a relative dielectric constant of 2.2 and a thickness of 0.508 mm; the feed horn antenna 2 is a standard gain horn antenna with a -10 dB beam width of 64 degrees, and the distance F between the phase center of the feed horn antenna and the center of the phase shift metasurface is 346 mm; the number of quasi-non-diffractive beams in this example is 3, the included angles between the beams and the phase shift metasurface are 45 degrees, 90 degrees, and 135 degrees respectively, the starting points of the quasi-non-diffractive beams are 100 mm, 100 mm, and 200 mm respectively, the depths of field are 200 mm, 400 mm, and 300 mm respectively, and the distances from the centers of the dielectric substrates are p The ideal phase shift amount of the phase shift unit is:

[0074] (1)

[0075] (2)

[0076] (3)

[0077] (4)

[0078] (5)

[0079] (6)

[0080] (7)

[0081] wherein, is the operating frequency of the antenna, is the speed of light in free space, and is the coordinate of the center point of each phase shift unit, the coordinate axis is shown as Figure 3 , F is the distance from the phase center of the feed horn antenna to the phase shift super surface, is the radius of the phase shift super surface, p is the distance from each phase shift unit to the center of the phase shift super surface, θ is the angle between the beam direction and the phase shift super surface 1, and are used to control the depth of field of the quasi-diffraction-free beam and the starting point of the quasi-diffraction-free area, respectively.

[0082] According to the position of each phase shift unit, the phase shift amount of each phase shift unit is calculated according to the above formulas (1)-(7), the corresponding phase shift unit is selected according to the phase shift amount, and the phase shift super surface 1 is laid out, and the expected quasi-diffraction-free beam is generated according to the generated phase distribution. In the design, changing θ , and z 1 realizes quasi-diffraction-free beams with different directions and different areas.

[0083] The ideal phase shift amount is the theoretical phase difference between each phase shift unit and the center position of the phase shift super surface. In this example, the actual phase shift amount is:

[0084] 90°

[0085] wherein, int is the floor function; by changing the side length of the three-layer metal patch in each phase shift unit, the phase requirement of the quasi-diffraction-free beam on the exit surface of the phase shift super surface can be met; the sizes of the metal patches corresponding to the four phase shift amplitudes are obtained through periodic boundary conditions in the Ansys HFSS full-wave simulation software; in this embodiment, the relationship between the phase shift amount and the side length of the metal patch is:

[0086]

[0087] Therefore, the design of the phase shift super surface can be completed, and a linearly polarized standard gain horn antenna 2 with a -10dB beam width of 64 degrees is applied on the left side of the phase shift super surface to feed, and the horn antenna is opposite to the center of the phase shift super surface, as shown in Figure 1 , so that a linearly polarized quasi-diffraction-free beam can be generated on the right side of the phase shift super surface.

[0088] As shown in Figure 6The longitudinal section and cross section simulation diagram of the quasi-non-diffracting beam electric field strength generated by the application are shown, and it can be seen from the diagram that within the range of 500 millimeters, the electromagnetic wave field strength is distributed in a beam shape on the propagation axis, is symmetrical along the propagation axis, and the field strength remains basically unchanged, the quasi-non-diffracting beam is generated in the expected range, and the design expectation is achieved.

[0089] Example 2

[0090] On the basis of example 1, the number of quasi-non-diffracting beams is changed to 1, and beam 1 (the starting point of the quasi-non-diffracting area is adjustable) and beam 2 (the starting point of the quasi-non-diffracting area is located on the beam generating device) are generated respectively, the included angle between beam 1 and the phase shift metasurface is 90 degrees, the starting point of the quasi-non-diffracting beam is 200 millimeters, and the depth of field is 300 millimeters, the included angle between beam 2 and the phase shift metasurface is 90 degrees, the starting point of the quasi-non-diffracting beam is 0 millimeter, and the depth of field is 500 millimeters, as shown in Figure 7 The comparison diagram of the axial electric field strength of the quasi-non-diffracting beam generated by the application and the axial electric field strength of the quasi-non-diffracting beam with a fixed starting point of the quasi-non-diffracting area is shown. It can be seen from the diagram that within the target area (200 millimeters to 500 millimeters), the electric field strength of the quasi-non-diffracting beam proposed by the application is always higher than that of the quasi-non-diffracting beam with the starting point of the quasi-non-diffracting area located on the generating device, which indicates that in the application scenario where the target area is far away from the generating device, the quasi-non-diffracting beam proposed by the application has stronger and more concentrated energy than the traditional quasi-non-diffracting beam.

[0091] The application relates to a quasi-non-diffracting beam antenna capable of generating a quasi-non-diffracting area and a scanning angle.

[0092] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the application being indicated by the following claims.

[0093] It should be understood that the application is not limited to the precise construction that has been described above and shown in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application. The scope of the application is indicated only by the appended claims.

Claims

1. An antenna implementing quasi-non-diffracting beamforming and scanning, characterized in that, The application relates to a phase shift super surface and a feed horn antenna, and the feed horn antenna is opposite to the geometric center of the phase shift super surface; the phase shift super surface is a double-layer dielectric substrate structure with a phase shift function of electromagnetic waves, and comprises, from top to bottom, a printed circuit upper layer, a dielectric substrate upper layer, a printed circuit middle layer, a dielectric substrate lower layer and a printed circuit lower layer which are coaxially stacked in sequence; the whole phase shift super surface is composed of a plurality of periodically arranged phase shift units; the structure of each phase shift unit comprises upper, middle and lower metal patches and upper and lower dielectric substrates. The phase shift unit is equivalent to a low-pass filter phase shifter with a phase shift effect; by setting the size of the three-layer metal patches in each phase shift unit on the phase shift super surface, 0 degrees, -90 degrees, -180 degrees and -270 degrees of insertion phase shift can be realized at any position of the phase shift super surface; then, under the irradiation of the feed horn antenna, a phase distribution satisfying the ideal phase shift amount of the quasi-non-diffracting wave beam is generated on the outlet surface of the phase shift super surface, so as to generate the quasi-non-diffracting wave beam. An ideal phase shift amount of each phase shift unit of the phase shift super surface From formulas (1)-(7), we have: (1) (2) (3) (4) (5) (6) (7) wherein, is the operating frequency of the antenna, c is the speed of light in free space, and is the coordinate of the center point of each phase shift unit, F is the distance from the phase center of the feed horn antenna to the phase shift metasurface, is the radius of the phase shift metasurface, The phase shift unit is rectangular or hexagonal; when the phase shift unit is rectangular, the phase shift units are arranged in a square needle shape; and when the phase shift unit is hexagonal, the phase shift units are arranged in a honeycomb shape. is the distance from each phase shift unit to the center of the phase shift metasurface, is the angle between the beam direction and the phase shift metasurface, and are used to control the depth of field of the quasi-non-diffracting beam and the starting point of the quasi-non-diffracting region, respectively.

2. The antenna that implements quasi-non-diffracting beamforming and scanning of claim 1, wherein, The size of the metal patch in the phase shift unit corresponding to different phase shift amplitudes is obtained through periodic boundary conditions in full-wave simulation software.

3. The antenna that implements quasi-nondiffractive beamforming and scanning of claim 1, wherein, The feed horn antenna is a linearly polarized, circularly polarized or multi-polarized horn antenna.

4. The antenna that implements quasi-nondiffractive beamforming and scanning of claim 1, wherein, In each phase shift unit, the size of the lower printed circuit metal patch is the same as that of the upper printed circuit metal patch.

5. The antenna that implements quasi-nondiffractive beamforming and scanning of claim 1, wherein, The size of the metal patch in the phase shift unit corresponding to different phase shift amplitudes is obtained through periodic boundary conditions in full-wave simulation software.

6. A design method for an antenna that achieves quasi-diffraction-free beamforming and scanning, characterized in that, According to the phase shift amount, a corresponding phase shift unit is selected, a layout is composed into a phase shift metasurface, and according to a generated phase distribution, a desired quasi-non-diffracting beam can be generated 、 and Quasi-non-diffracting beams with different directions and different areas are realized. According to the position of each phase shift unit, the ideal phase shift amount of the phase shift unit is calculated according to formulas (1)-(7). Based on the ideal phase shift amount, the actual phase shift amount is calculated. (1) (2) (3) (4) (5) (6) (7) wherein, is the operating frequency of the antenna, c is the speed of light in free space, and is the coordinate of the center point of each phase shift unit, F is the distance from the phase center of the feed horn antenna to the phase shift metasurface, is the radius of the phase shift metasurface, Based on the actual phase shift amount, the size of the metal patch corresponding to the phase shift unit at different positions is selected. is the distance from each phase shift unit to the center of the phase shift metasurface, is the angle between the beam direction and the phase shift metasurface, and are used to control the depth of field of the quasi-non-diffracting beam and the starting point of the quasi-non-diffracting area, respectively; The actual phase shift amount is calculated based on the ideal phase shift amount, and the following formula is adopted: ​ 7. The method of designing an antenna to achieve quasi-non-diffracting beamforming and scanning of claim 6, wherein, ​ 90° wherein is a floor function, is an ideal phase shift amount, is an actual phase shift amount.

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