A low sidelobe, wide scanning angle vortex wave antenna and its implementation method

Abstract

The present invention discloses a low sidelobe and wide scanning angle vortex wave antenna and an implementation method thereof, which includes a first annular antenna sub-array, a second annular antenna sub-array and a third annular antenna sub-array that are installed on the same installation surface and are concentrically arranged; the first annular antenna sub-array, the second annular antenna sub-array and the third annular antenna sub-array are each composed of a plurality of antenna elements arranged uniformly; each antenna element includes an electric dipole and a magnetic dipole; by designing different annular antenna sub-arrays and designing electric dipoles and magnetic dipoles in the antenna elements of each annular antenna sub-array, the present invention solves the problem of the increase in sidelobe level during the beam scanning process, and the sidelobe level of the scanning vortex beam generated is smaller than that of the traditional antenna, so that a larger vortex wave scanning angle can be achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of microwave radio frequency antennas, and particularly relates to a low sidelobe and wide scanning angle vortex wave antenna and a method for realizing the same. Background Art

[0002] When the traditional conical beam antenna deflects at a large angle, the sidelobe level will increase, affecting the reception of long-distance signals. Due to its inherent divergence, the sidelobe level of the vortex beam is already relatively high when the beam is in the non-deflected state, and it will deteriorate further during the scanning process, thereby reducing the beam quality. Therefore, reducing the sidelobe level of the vortex beam is the key to increasing the beam scanning angle.

[0003] In order to realize a wide scanning angle vortex beam, an array antenna combining a taper distribution and Chebyshev is usually adopted, but such antennas still have the problem of too high sidelobe level during the scanning process, which greatly limits the scanning angle of the vortex beam. Summary of the Invention

[0004] The purpose of the present invention is to provide a low sidelobe and wide scanning angle vortex wave antenna and a method for realizing the same, so as to reduce the sidelobe level of the vortex beam and increase the scanning angle of the vortex beam.

[0005] The present invention adopts the following technical solutions: A low sidelobe and wide scanning angle vortex wave antenna includes a first circular antenna sub-array, a second circular antenna sub-array, and a third circular antenna sub-array that are installed on the same mounting surface and are concentrically arranged;

[0006] The radii of the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are successively λ / 2, λ and 3 λ / 2; where λ is the free space wavelength corresponding to the antenna operating frequency;

[0007] The first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are all composed of a number of antenna elements arranged uniformly;

[0008] Each antenna element includes an electric dipole and a magnetic dipole;

[0009] Among them, the feeding amplitudes of the antenna elements on the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are different.

[0010] Further, the normalized values of the feeding amplitudes of the antenna elements in the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array follow the Bayliss distribution.

[0011] Further, the antenna element includes a circular substrate;

[0012] The first side of the substrate is attached with a first oscillator and a fourth oscillator that are perpendicular to each other;

[0013] Both the first oscillator and the fourth oscillator are strip-shaped, and the two are connected to the middle of the substrate;

[0014] The second side of the substrate is attached with a second oscillator and a third oscillator that are perpendicular to each other;

[0015] Both the second oscillator and the third oscillator are strip-shaped, and the two are connected to the middle of the substrate;

[0016] The first oscillator and the second oscillator are collinear, and the two are arranged along the radial direction of the substrate;

[0017] The fourth oscillator and the third oscillator are collinear; and the two are arranged along the radial direction of the substrate;

[0018] The free ends of the first oscillator, the fourth oscillator, the second oscillator, and the third oscillator are all arranged on the outer periphery of the substrate.

[0019] Further, both the first oscillator and the fourth oscillator are connected to the inner conductor of the coaxial line;

[0020] Both the second oscillator and the third oscillator are connected to the outer conductor of the coaxial line.

[0021] Further, both between the first oscillator and the fourth oscillator and between the second oscillator and the third oscillator are connected by an arc-shaped ring.

[0022] Further, on the second side of the substrate and between the projections of the first oscillator and the fourth oscillator, between the second oscillator and the third oscillator, between the projection of the fourth oscillator and the second oscillator, and between the projection of the first oscillator and the third oscillator, sector-shaped patches are all arranged; wherein, the second side is the opposite side of the first side;

[0023] The outer arc of the sector-shaped patch coincides with the outer periphery of the substrate;

[0024] The outer arc of the sector-shaped patch is connected with an arc-shaped piece perpendicular to the second side of the substrate, and one arc side of the arc-shaped piece is connected with the outer arc of the sector-shaped patch.

[0025] Further, the other arc side of the arc-shaped piece is connected with a metal bottom plate.

[0026] Further, there is a gap between the straight side of the sector-shaped patch and the corresponding first oscillator, fourth oscillator, second oscillator, and third oscillator.

[0027] Further, there is a gap between adjacent sector-shaped patches.

[0028] Another technical solution of the present invention: A method for implementing the above-mentioned low sidelobe and wide scanning angle vortex wave antenna, calculating the feeding amplitudes of the antenna elements in the first annular antenna sub-array, the second annular antenna sub-array, and the third annular antenna sub-array includes:

[0029] ,

[0030] wherein, when , represents the feeding amplitude of the antenna element in the first annular antenna sub-array, when , represents the feeding amplitude of the antenna element in the second annular antenna sub-array, when , represents the feeding amplitude of the antenna element in the third annular antenna sub-array, represents the number of equal-power sidelobes in the antenna pattern, , B n represents n the corresponding Bayliss distribution coefficient, N = 3.

[0031] The beneficial effects of the present invention are: By designing different annular antenna sub-arrays and designing electric dipoles and magnetic dipoles in the antenna elements of each annular antenna sub-array, the present invention solves the problem of the increase in sidelobe level during the beam scanning process. Compared with the scanning vortex beam generated by the traditional antenna, the sidelobe level is smaller, so that a larger vortex wave scanning angle can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a schematic structural diagram of a low sidelobe and wide scanning angle vortex wave antenna according to an embodiment of the present invention;

[0033] Figure 2 is a schematic structural diagram of an antenna element according to an embodiment of the present invention;

[0034] Figure 3 is a schematic side view structural diagram of an antenna element according to an embodiment of the present invention;

[0035] Figure 4 is a schematic internal structural diagram of an antenna element according to an embodiment of the present invention;

[0036] Figure 5 is a schematic connection structural diagram of an electric dipole and a coaxial cable according to an embodiment of the present invention;

[0037] Figure 6 is the far-field pattern of the antenna according to an embodiment of the present invention;

[0038] Figure 7This is the far - field phase distribution diagram when the beam of the antenna radiation in the embodiment of the present invention deflects by 15°;

[0039] Figure 8 This is the far - field phase distribution diagram when the beam of the antenna radiation in the embodiment of the present invention deflects by 30°;

[0040] Figure 9 This is the far - field phase distribution diagram when the beam of the antenna radiation in the embodiment of the present invention deflects by 45°;

[0041] Figure 10 This is the modal spectrum diagram of the antenna in the embodiment of the present invention;

[0042] Figure 11 This is the reflection coefficient curve diagram of the antenna element in the embodiment of the present invention;

[0043] Figure 12 This is the pattern and axial ratio curve diagram of the antenna element with an azimuth angle of 0° in the embodiment of the present invention;

[0044] Figure 13 This is the pattern and axial ratio curve diagram of the antenna element with an azimuth angle of 90° in the embodiment of the present invention;

[0045] Figure 14 This is the comparison diagram of the antenna patterns with different feeding methods in the embodiment of the present invention.

[0046] Wherein: 10. Antenna element; 11. First oscillator; 12. Fourth oscillator; 13. Substrate; 14. Second oscillator; 15. Third oscillator; 16. Arc - shaped piece; 17. Metal bottom plate; 18. Sector - shaped patch; 20. Mounting plate; 30. Coaxial cable. Detailed implementation manner

[0047] The present invention will be described in detail below with reference to the drawings and specific implementation manners.

[0048] The present invention discloses a low - sidelobe, wide - scanning - angle vortex - wave antenna, as Figure 1 shown, which includes a first circular - antenna sub - array, a second circular - antenna sub - array, and a third circular - antenna sub - array that are installed on the same mounting surface and are concentrically arranged; the radii of the first circular - antenna sub - array, the second circular - antenna sub - array, and the third circular - antenna sub - array are successively λ / 2, λ and 3 λ / 2; wherein, λis the free space wavelength corresponding to the antenna operating frequency; the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are each composed of a number of antenna elements 10 arranged uniformly; each antenna element 10 includes an electric dipole and a magnetic dipole; wherein, the feeding amplitudes of the antenna elements 10 on the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are different.

[0049] By designing different circular antenna sub-arrays and designing electric dipoles and magnetic dipoles in the antenna elements 10 of each circular antenna sub-array, the present invention solves the problem of the increase in sidelobe level during the beam scanning process. Compared with the scanning vortex beam generated by the traditional antenna, the sidelobe level is smaller, so that a larger scanning angle of the vortex wave can be achieved.

[0050] In the present invention, a number of antenna elements 10 are arranged uniformly on three concentric circular antenna sub-arrays to form three circular arrays, thereby generating a vortex beam. The three circular antenna sub-arrays are all mounted on the same mounting plate 20.

[0051] In an embodiment of the present invention, the numbers of the antenna elements 10 on the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are 6, 12, and 18 in sequence.

[0052] In this antenna, a number of antenna elements 10 arranged along the radial direction of the antenna are regarded as constituting a linear array. The normalized value of the feeding amplitude of the linear array follows the Bayliss distribution, which can reduce the sidelobe level of the vortex beam. That is to say, the normalized values of the feeding amplitudes of the antenna elements 10 in the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array follow the Bayliss distribution. The antenna feeding uses a phase shifter, which can excite a vortex wave with a mode number of +1 and can achieve a wide-angle beam scanning of 0° - 45°. That is, the wide scanning angle in the present invention refers to a scanning angle of 0° - 45°.

[0053] In an embodiment, as Figure 2 shown, the antenna element 10 includes a circular substrate 13; a first oscillator 11 and a fourth oscillator 12 perpendicular to each other are attached to the first surface of the substrate 13; both the first oscillator 11 and the fourth oscillator 12 are strip-shaped, and the two are connected to the middle of the substrate 13; as Figure 5 shown, a second oscillator 14 and a third oscillator 15 perpendicular to each other are attached to the second surface of the substrate 13; both the second oscillator 14 and the third oscillator 15 are strip-shaped, and the two are connected to the middle of the substrate 13; the first oscillator 11 and the second oscillator 14 are collinear, and the two are arranged along the radial direction of the substrate 13; the fourth oscillator 12 and the third oscillator 15 are collinear; and the two are arranged along the radial direction of the substrate 13; the free ends of the first oscillator 11, the fourth oscillator 12, the second oscillator 14, and the third oscillator 15 are all arranged on the outer periphery of the substrate 13.

[0054] As Figure 3 , Figure 4 and Figure 5 shown, both the first oscillator 11 and the fourth oscillator 12 are connected to the inner conductor of the coaxial line 30; both the second oscillator 14 and the third oscillator 15 are connected to the outer conductor of the coaxial line 30. Between the first oscillator 11 and the fourth oscillator 12, and between the second oscillator 14 and the third oscillator 15, they are connected by an arc-shaped ring.

[0055] Through the above design, the first oscillator 11 and the second oscillator 14 form an electric dipole, and the fourth oscillator 12 and the third oscillator 15 form another electric dipole. The two arms of the electric dipole (i.e., the corresponding two oscillators) are respectively printed on two surfaces of the substrate 13. When feeding, the first oscillator 11 and the fourth oscillator 12 located on the first surface of the substrate 13 are connected by a metal arc-shaped ring with three-quarter circumference, and then connected to the inner conductor of the coaxial line 30. The second oscillator 14 and the third oscillator 15 located on the second surface of the substrate 13 are similarly connected by a metal arc-shaped ring with three-quarter circumference, and then connected to the outer conductor of the coaxial line 30. The function of the metal arc-shaped ring is to provide a 90° feeding phase difference for the two cross-placed electric dipoles, thereby synthesizing circularly polarized radiation.

[0056] On the second surface of the substrate 13 and between the projections of the first oscillator 11 and the fourth oscillator 12, between the second oscillator 14 and the third oscillator 15, between the projection of the fourth oscillator 12 and the second oscillator 14, and between the projection of the first oscillator 11 and the third oscillator 15, sector-shaped patches 18 are provided; wherein, the second surface is the opposite surface of the first surface; the projection of the first oscillator 11 refers to the projection of the first oscillator 11 on the second surface, and the projection of the fourth oscillator 12 refers to the projection of the fourth oscillator 12 on the second surface.

[0057] The outer arc of the sector-shaped patch 18 coincides with the outer circumference of the substrate 13; the outer arc of the sector-shaped patch 18 is connected to an arc-shaped piece 16 perpendicular to the second surface of the substrate 13, and one arc edge of the arc-shaped piece 16 is connected to the outer arc of the sector-shaped patch 18. The other arc edge of the arc-shaped piece 16 is connected to a metal bottom plate 17. The length of the arc-shaped piece 16 is designed to be one-quarter wavelength.

[0058] It should be noted that there is a gap between the straight edge of the sector-shaped patch 18 and the corresponding first oscillator 11, fourth oscillator 12, second oscillator 14, and third oscillator 15. There is a gap between adjacent sector-shaped patches 18.

[0059] Between two cross - placed electric dipoles, four spaces are formed. Therefore, sector patches 18 and arc - shaped pieces 16 are arranged in all of these four spaces. Combining a part of the metal floor 17 and the coaxial line 30 forms four magnetic dipoles. The magnetic dipoles are coupled and fed by the electric dipoles, which can broaden the half - power beam width and the axial - ratio beam width of the antenna element 10.

[0060] The antenna element 10 of the present invention is a wide - beam right - hand circularly polarized antenna. Each antenna element 10 is fed by a 50Ω coaxial line 30, and its operating frequency band is 2.3 GHz.

[0061] As a specific implementation method, adjusting the feeding phase of the antenna element 10 can excite the vortex wave and achieve scanning. The specific calculation of the required phase is as follows:

[0062] Taking the innermost first circular antenna sub - array as an example, all antenna elements 10 are evenly arranged along the circumference with a radius of λ / 2. Assuming the current of the p th antenna element 10 is ( A p represents the current value), represents the phase of the p th antenna element 10. Then the direction function of this antenna sub - array at the field point in the antenna radiation field is:

[0063] ,

[0064] Among them, r 、 θ 、 respectively represent the distance, elevation angle, and azimuth angle of the field point relative to the center point of the antenna. j represents the imaginary unit, k represents the wave number in free space, , represents the azimuth angle of the p th antenna element 10, , P represents the number of array elements on this circular antenna sub - array.

[0065] Furthermore, if the direction of the beam maximum is to be , then the phase of the p th antenna element 10 should be . Among them, represents the elevation angle of the direction of the beam maximum, represents the azimuth angle of the direction of the beam maximum.

[0066] The antenna generates a modulus of The requirements for the vortex wave are as follows: the feeding amplitudes of the antenna elements 10 in the circular antenna sub-array are the same, and the deflection phase between the antenna elements 10 is . Therefore, to make the modulus of the vortex beam point to , the feeding phase of the p th antenna element 10 should be the superposition of the deflection phase and the vortex phase, which can be written as:

[0067] .

[0068] In Figure 6 , the abscissa is the elevation angle and the ordinate is the antenna gain. When the beam points to 0°, the main lobe gain is 13.5 dBic, the main-to-side lobe isolation is 28.2 dB, and the mode purity is 0.99; when the beam scans to 30°, the main lobe gain is 13.5 dBic, the main-to-side lobe isolation is 19.5 dB, and the mode purity is 0.95; when the beam scans to 45°, the main lobe gain is 13.5 dBic, the main-to-side lobe isolation is 17 dB, and the mode purity is 0.91. It can be seen from this that as the scanning angle increases, the main-to-side lobe isolation and the modal purity of the antenna both deteriorate, but it meets the requirements that the main-to-side lobe isolation is greater than 10 dB and the main lobe gain decreases by less than 3 dB during scanning.

[0069] Figure 7 indicates that when the beam radiated by the antenna deflects by 15°, a 360-degree phase change occurs in the plane perpendicular to the propagation direction. Figure 8 indicates that when the beam radiated by the antenna deflects by 30°, a 360-degree phase change occurs in the plane perpendicular to the propagation direction. Figure 9 indicates that when the beam radiated by the antenna deflects by 45°, a 360-degree phase change occurs in the plane perpendicular to the propagation direction, that is, when the beam radiated by the antenna deflects by 15°, 30°, and 45°, the vortex wave with a modal number of 1 is radiated.

[0070] Figure 10 indicates that the modal purity of the beam radiated by the antenna is the highest when the modal number is 1, and it can be considered that the beam radiated by the antenna is a vortex wave with a modal number of 1.

[0071] It can be seen from this that after the present invention uses the phase shifter to provide the phase required for exciting the vortex wave and the phase of the beam offset, the vortex wave with a modal number of +1 is excited and the beam is scanned from 0° to 45°.

[0072] As a specific implementation method, in this embodiment, the substrate 13 is selected as Duroid RO4003 with a thickness of 1 mm, a relative dielectric constant of 3.38, and a diameter of 61.5 mm. The specific parameters of the antenna element 10 are as follows:

[0073] Widths of the first oscillator 11 and the second oscillator 14 w 1 = 3.5 mm, lengths of the first oscillator 11 and the second oscillator 14 = 25.8 mm, widths of the widened end sections of the first oscillator 11 and the second oscillator 14 w 2 = 11 mm, lengths of the third oscillator 15 and the fourth oscillator 12 = 30.1 mm, radii of the semi-circular end portions of the third oscillator 15 and the fourth oscillator 12 close to the center of the substrate 13 r = 5.6 mm, height of the arc-shaped sheet 16 h = 20 mm, central angle of the sector-shaped patch 18 is 80°.

[0074] The metal arc-shaped ring introduces a 90° phase difference to the crossed electric dipole, such that at t = 0, the current on the electric dipole is maximum at J 1, and its current direction is horizontal. At this time, the electric dipole is the main radiation patch. In addition, the currents on the sector-shaped patch 18, the arc-shaped sheet 16, the coaxial line 30 and the metal bottom plate 17 form a co-directional current loop J 2. Since the radius of the sector-shaped patch 18 is close to the oscillator length of the electric dipole patch, approximately equal to one-quarter of the free space wavelength, and the length of the arc-shaped sheet 16 is also approximately equal to one-quarter of the wavelength, the electrical length of the formed current loop is approximately equal to one wavelength. Therefore, this current loop can be equivalent to a magnetic current M . Similarly, the diagonal arc-shaped sheets 16 and sector-shaped patches 18 can also be equivalent to co-directional magnetic currents M . The E-plane and H-plane radiation patterns of the electric dipole are respectively in the shape of "∞" and " " shapes, while the E-plane and H-plane radiation patterns of the magnetic dipole are respectively in the shape of " " shape and "∞" shape, which are complementary to the radiation patterns of the electric dipole. The combination of the two forms a magneto-electric dipole, making the E-plane and H-plane radiation patterns of the antenna similar in shape and broadening the beam width of the antenna.

[0075] The antenna element 10 of the present invention radiates a right-handed circularly polarized wave at 2.3 GHz, with a gain of 3.5 dBic. The half-power beam widths are 145° and 144.3° respectively at azimuth angles of 0° and 90°, and the 3 dB axial ratio beam widths are 156° and 148° respectively.

[0076] As Figure 11 shown, the reflection coefficient of the antenna is less than -10 dB in the frequency band of 1.9 - 2.73 GHz, and the antenna can normally radiate a beam in this frequency band.

[0077] As Figure 12As shown, when the azimuth angle is 0°, the antenna radiation beam is a right-handed beam, and within the range of elevation angles from 71° to -74°, the circular polarization axial ratio is less than 3 dB, and the antenna radiation beam is a right-handed circular polarization wave.

[0078] As Figure 13 shown, when the azimuth angle is 90°, the antenna radiation beam is a right-handed beam, and within the range of elevation angles from -72° to 72.5°, the circular polarization axial ratio is less than 3 dB, and the antenna radiation beam is a right-handed circular polarization wave.

[0079] In addition, the Bayliss distribution, Taylor distribution, and equal-amplitude feeding method are respectively used to feed the antenna, and the sidelobe level A= -30 dB, , and the normalized feeding amplitude values of the antenna element 10 on each circular antenna sub-array obtained by calculation are shown in Table 1. As Figure 14 shown, the sidelobe level of the beam generated by using the Bayliss distribution method for feeding is the lowest among the three methods.

[0080] Table 1

[0081]

[0082] The present invention also discloses a method for implementing the above-mentioned low-sidelobe and wide-scan-angle vortex wave antenna. For a line source with a length of L , its discretized excitation function can be expressed as:

[0083] ,

[0084] wherein, represents the feeding amplitude at position d , d represents the position where the discretized excitation is located in the line source with a length of L , B n is n the corresponding Bayliss distribution coefficient, represents the number of equal-power sidelobes in the antenna pattern, .

[0085] Thus, for a line source, its discretized excitation function can be expressed as the following formula, that is, calculating the feeding amplitudes of the antenna element 10 in the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array includes:

[0086] ,

[0087] wherein, when , represents the feeding amplitude of the antenna element 10 in the first circular antenna sub-array, and when When represents the feeding amplitude of the antenna element 10 in the second circular antenna sub-array. When When represents the feeding amplitude of the antenna element 10 in the third circular antenna sub-array, represents the number of equal-power sidelobes in the antenna pattern, , B n represents n the corresponding Bayliss distribution coefficient, N = 3.

[0088] More specifically, the calculation method of the Bayliss distribution coefficient is as follows:

[0089] ,

[0090] In the Bayliss distribution, generally, the feeding amplitude of the element at the center position is set to 0. Therefore, there is no antenna element 10 at the center of the substrate 13, and a linear array with 7 antenna elements 10 is formed along the radial direction of the antenna array. The sidelobe level is set A = -30 dB, and the number of equal-power sidelobes , , , is a fixed value related to the sidelobe level, and its values are listed in Table 2; the normalized amplitudes of the Bayliss distribution feeding are obtained by calculation: 0.3371, 0.8388, 1, 0, 1, 0.8388, 0.3371.

[0091] In addition, for a linear array using Bayliss synthesis, its antenna pattern can be expressed as:

[0092] ,

[0093] where x is a variable in radian measure. The antenna pattern has zeros at x = 0 and x = ±( n + 0.5), but the zero at x = 0 cancels out with the denominator in the formula. Therefore, if only the zeros between ±( n + 0.5) are moved, while the zeros at ±( n + 0.5) and beyond are fixed, in order to reduce the sidelobe level, the above formula can be modified as:

[0094] ,

[0095] where σx n is the new zero position of the antenna pattern, , , A is the sidelobe level, is a fixed value related to the sidelobe level, and its value is listed in Table 2.

[0096] Table 2

[0097]

[0098] In summary, the wide-scan-angle vortex wave array antenna designed by the present invention adopts a concentric ring array with Bayliss amplitude distribution, improves the sidelobe level during the beam scanning process, and increases the scanning angle of the vortex wave.

Claims

1. A low sidelobe, wide scanning angle vortex wave antenna, characterized in that, It includes a first circular antenna sub-array, a second circular antenna sub-array, and a third circular antenna sub-array that are installed on the same mounting surface and are concentrically arranged; The radii of the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are successively λ / 2, λ and 3 λ / 2; where λ is the free space wavelength corresponding to the antenna operating frequency; The first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are each composed of a number of antenna elements (10) arranged uniformly; Each of the antenna elements (10) includes an electric dipole and a magnetic dipole; Among them, the feeding amplitudes of the antenna elements (10) on the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array are different; The normalized values of the feeding amplitudes of the antenna elements (10) on the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array follow the Bayliss distribution; The antenna element (10) includes a circular substrate (13); A first oscillator (11) and a fourth oscillator (12) that are perpendicular to each other are attached to the first surface of the substrate (13); Both the first oscillator (11) and the fourth oscillator (12) are strip-shaped, and the two are connected to the middle of the substrate (13); A second oscillator (14) and a third oscillator (15) that are perpendicular to each other are attached to the second surface of the substrate (13); Both the second oscillator (14) and the third oscillator (15) are strip-shaped, and the two are connected to the middle of the substrate (13); The first oscillator (11) and the second oscillator (14) are collinear and are arranged along the radial direction of the substrate (13); The fourth oscillator (12) and the third oscillator (15) are collinear and are arranged along the radial direction of the substrate (13); The free ends of the first oscillator (11), the fourth oscillator (12), the second oscillator (14), and the third oscillator (15) are all arranged on the outer periphery of the substrate (13); Both the first oscillator (11) and the fourth oscillator (12) are connected to the inner conductor of the coaxial line (30); Both the second oscillator (14) and the third oscillator (15) are connected to the outer conductor of the coaxial line (30); Both between the first oscillator (11) and the fourth oscillator (12), and between the second oscillator (14) and the third oscillator (15) are connected by an arc-shaped ring; Scanning is achieved by adjusting the feeding phase of the antenna element (10). The feeding phase of the p n-th antenna element (10) is the superposition of the deflection phase and the vortex phase, written as: ， Among them, is the feeding phase of the p th antenna element (10), k represents the wave number in free space, , represents the elevation angle of the beam maximum direction, represents the azimuth angle of the beam maximum direction, represents the p th azimuth angle of the antenna element (10), l is the modulus of the vortex wave, is the deflection phase between antenna elements (10).

2. The low sidelobe and wide scanning angle vortex wave antenna according to claim 1, characterized in that, On the second surface of the substrate (13) and between the projections of the first oscillator (11) and the fourth oscillator (12), between the second oscillator (14) and the third oscillator (15), between the projection of the fourth oscillator (12) and the second oscillator (14), and between the projection of the first oscillator (11) and the third oscillator (15), sector-shaped patches (18) are provided; where the second surface is the opposite surface of the first surface; The outer arc of the sector-shaped patch (18) coincides with the outer periphery of the substrate (13); The outer arc of the sector-shaped patch (18) is connected to an arc-shaped piece (16) perpendicular to the second surface of the substrate (13), and one arc-shaped side of the arc-shaped piece (16) is connected to the outer arc of the sector-shaped patch (18).

3. A low sidelobe and wide scanning angle vortex wave antenna according to claim 2, characterized in that, The other arc-shaped side of the arc-shaped piece (16) is connected to a metal bottom plate (17).

4. The low sidelobe and wide scanning angle vortex wave antenna according to claim 2, wherein, There is a gap between the straight side of the sector patch (18) and the corresponding first oscillator (11), fourth oscillator (12), second oscillator (14), and third oscillator (15).

5. The low sidelobe and wide scanning angle vortex wave antenna according to claim 4, characterized in that, There is a gap between adjacent sector patches (18).

6. A method for implementing a low sidelobe and wide scanning angle vortex wave antenna according to any one of claims 1-5, characterized in that, Calculating the feeding amplitude of the antenna elements (10) in the first circular antenna sub-array, the second circular antenna sub-array, and the third circular antenna sub-array includes: ， Among them, when i = 1, represents the feeding amplitude of the antenna element (10) in the first circular antenna sub-array. When i = 2, represents the feeding amplitude of the antenna element (10) in the second circular antenna sub-array. When i = 3, represents the feeding amplitude of the antenna element (10) in the third circular antenna sub-array. represents the number of equal-power side lobes in the antenna pattern, , B n represents n the corresponding Bayliss distribution coefficient, N = 3.

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