CN120280702A - Low-sidelobe microwave antenna and design method thereof - Google Patents

Abstract

The invention discloses a low-sidelobe microwave antenna, which comprises a main reflecting surface, a feed source and a surrounding edge, wherein the main reflecting surface is of a rotary paraboloid structure, the feed source is arranged at a focus of the main reflecting surface, the feed source comprises a radiation source, a secondary reflecting surface, a circular waveguide and a medium ring arranged on a splash plate, the surrounding edge is arranged around the edge of the main reflecting surface and is used for absorbing signals exceeding the receiving range of the main reflecting surface, the geometric parameters of the medium ring are configured to enable a feed source directional diagram to conform to improved generalized Taylor displacement distribution, and the expression of the improved generalized Taylor displacement distribution is as follows: Wherein r _b is the central shielding radius, B1 is a constant larger than 0.45, J0 is the value of the first zero point of the 0 th order Bessel function, and the microwave antenna can achieve the effect of low side lobe by adjusting the geometric parameters of the medium ring based on the expression.

Description

Low-sidelobe microwave antenna and design method thereof

Technical Field

The invention relates to the technical field of communication antennas, in particular to a low-sidelobe microwave antenna and a design method thereof.

Background

With the rapid development of wireless communication technology, the microwave antenna has increasingly demanded in fields of mobile communication, satellite communication, radar system and the like, especially in complex electromagnetic environment and high-density equipment deployment scene, higher requirements are put on the performance of the antenna, while the traditional parabolic antenna and the cassegrain antenna can realize basic directional radiation function, the side lobe level of the traditional parabolic antenna and the cassegrain antenna generally only meets ETSICLASS3 standard (the side lobe level is about-30 dB to-35 dB), signal crosstalk is easy to be caused in multi-equipment coexistence or strong interference environment, and the cross polarization suppression capability is limited.

In the prior art, although the side lobe performance can be partially improved by a method of optimizing the feed source directional diagram through Taylor distribution, the problems that the directional diagram is insufficient in fitting degree with theoretical distribution, the edge diffraction field is difficult to effectively inhibit and the like still exist in practical application, so that the return loss is high, and the effect of low side lobe cannot be achieved.

Disclosure of Invention

The invention aims to at least solve one of the technical problems in the prior art, and provides a low-sidelobe microwave antenna and a design method thereof, by adjusting the geometric parameters of the medium ring, the feed source pattern accords with the improved generalized Taylor displacement distribution, and the return loss can be effectively reduced, so that the effect of low side lobe is achieved.

The embodiment of the invention provides a low-sidelobe microwave antenna, which comprises a main reflecting surface, a feed source and a surrounding edge, wherein the main reflecting surface is of a rotary paraboloid structure, the feed source is arranged at a focus of the main reflecting surface, the feed source comprises a radiation source, a secondary reflecting surface, a circular waveguide and a medium ring arranged on a splash plate, the surrounding edge is arranged around the edge of the main reflecting surface and is used for absorbing signals exceeding the receiving range of the main reflecting surface, the geometric parameters of the medium ring are configured to enable a feed source directional diagram to conform to improved generalized Taylor displacement distribution, and the expression of the improved generalized Taylor displacement distribution is as follows: Wherein r _b is the center shielding radius, B1 is a constant greater than 0.45, and J0 is the value of the first zero point of the 0 th order bessel function.

In some embodiments, the edges of the dielectric ring form a bevel, the bevel angle of which is configured such that the amplitude variation of the feed pattern conforms to the increasing or decreasing trend of the taylor distribution.

In some embodiments, in the modified generalized taylor displacement profile, r _b is set to 0.1 times the radius, B1 is set to 0.5, and the tuning range of the dielectric ring covers an annular area of 0.2 to 1 times the radius.

In some embodiments, a first wave-absorbing material is added to the inner side of the surrounding edge, the first wave-absorbing material is used for absorbing side lobe signals beyond 60 degrees, and a second wave-absorbing material is uniformly coated on the outer side of the circular waveguide along the circumferential direction.

In some embodiments, the inclined plane of the edge of the medium ring is a multi-step inclined plane, the multi-step inclined plane is composed of at least two stages of sub-inclined planes with different inclined angles, the sub-inclined planes at different stages are connected through a short transition section, and a sectional gradual change structure is integrally formed.

In some embodiments, the side lobe level of the microwave antenna is below-40 dB.

In some embodiments, the design method is applied to a low-sidelobe microwave antenna, the microwave antenna comprises a main reflecting surface, a feed source and a surrounding edge, wherein the main reflecting surface is of a rotary paraboloid structure, the feed source is arranged at a focus of the main reflecting surface, the feed source comprises a radiation source, a secondary reflecting surface, a circular waveguide and a medium ring arranged on a splash plate, the surrounding edge is arranged around the edge of the main reflecting surface and used for absorbing signals exceeding the receiving range of the main reflecting surface, and the geometric parameters of the medium ring are configured to enable a feed source directional diagram to conform to an improved generalized Taylor displacement distribution, and the expression of the improved generalized Taylor displacement distribution is as follows: The design method comprises the steps of calculating amplitude distribution parameters of a feed source directional diagram based on the improved generalized Taylor displacement distribution formula, and adjusting the geometric shape of a medium ring according to the amplitude distribution parameters to enable the feed source directional diagram to conform to Taylor distribution corresponding to the improved generalized Taylor displacement distribution formula, wherein r _b is a central shielding radius, B1 is a constant larger than 0.45, J0 is a value of a first zero point of a 0 th order Bezier function.

In some embodiments, after the adjusting the geometry of the dielectric ring, the design method further includes attaching a first wave-absorbing material inside the peripheral edge and uniformly coating a second wave-absorbing material outside the circular waveguide in a circumferential direction.

In some embodiments, after the adjusting the geometry of the dielectric ring, the design method further comprises verifying experimentally whether the side lobe level and the cross polarization of the microwave antenna meet a preset standard, and if not, adjusting the geometry of the dielectric ring again based on a preset rule.

In some embodiments, after the experiment verifies whether the sidelobe level and the cross polarization of the microwave antenna meet the preset standards, the design method further comprises adjusting the inclined plane angle of the edge of the dielectric ring according to the result of the experiment verification to enable the thickness of the dielectric in the signal path to be uniformly changed so as to optimize the fitting degree of the feed source directional diagram and the taylor distribution.

The microwave antenna with low side lobes and the design method thereof have the advantages that the microwave antenna at least comprises a main reflecting surface, a feed source and a surrounding edge, wherein the main reflecting surface adopts a rotary paraboloid structure, the feed source is arranged at a focus, the feed source consists of a radiation source, a secondary reflecting surface, a circular waveguide and a medium ring on a splash plate, the geometric parameters of the medium ring are optimized based on improved generalized Taylor displacement distribution, and the mathematical expression is as follows: Wherein r _b is the central shielding radius, B1 is a constant larger than 0.45, J0 is the value of the first zero point of the 0 th order Bessel function, and the distribution can enable the feed source directional diagram to be strictly attached to Taylor distribution in a radius area of 0.2-1 times by adjusting the geometric shape of a medium ring, such as a multi-step inclined plane design, so that the side lobe level is controlled below-40 dB, the return loss is reduced below-20 dB, and the performance index of the antenna is effectively improved.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate and do not limit the invention.

The invention is further described below with reference to the drawings and examples;

fig. 1 is a schematic structural diagram of a low side lobe microwave antenna according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a feed source according to an embodiment of the present invention;

Fig. 3 is a flowchart of a method for designing a low-sidelobe low-cross-polarization microwave antenna according to an embodiment of the present invention;

FIG. 4 is a flowchart illustrating steps for adjusting the geometry of a media ring according to one embodiment of the present invention;

fig. 5 is a feed pattern provided by an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein the accompanying drawings are used to supplement the description of the written description so that one can intuitively and intuitively understand each technical feature and overall technical scheme of the present invention, but not to limit the scope of the present invention.

In the description of the present invention, the meaning of several is one or more, the meaning of several is two or more, greater than, less than, exceeding, etc. are understood to exclude the present number, the above, below, within, etc. are understood to include the present number, "any one" means one or more, "at least one item below" and the like, and any combination of these items, including any combination of single items or plural items. The description of the first and second is for the purpose of distinguishing between technical features only and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

It should be noted that, in the embodiments of the present invention, terms such as setting, installing, connecting and the like should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meaning of the foregoing terms in the embodiments of the present invention in combination with the specific content of the technical solution. The term "coupled" may mean either a mechanical or an electrical connection or may communicate with each other, for example, or may be directly or indirectly coupled through an intermediary.

The technical features of the embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.

Currently, with the rapid development of wireless communication technology, the microwave antenna has increasingly demanded in fields of mobile communication, satellite communication, radar system and the like, especially in complex electromagnetic environment and high-density equipment deployment scene, higher requirements are put on the performance of the antenna, while the conventional parabolic antenna and the cassegrain antenna can realize basic directional radiation function, the side lobe level of the conventional parabolic antenna and the cassegrain antenna generally only meets ETSICLASS standard (the side lobe level is about-30 dB to-35 dB), signal crosstalk is easy to be caused in multi-equipment coexistence or strong interference environment, and the cross polarization suppression capability is limited. In the prior art, although the side lobe performance can be partially improved by a method of optimizing the feed source directional diagram through Taylor distribution, the problems that the directional diagram is insufficient in fitting degree with theoretical distribution, the edge diffraction field is difficult to effectively inhibit and the like still exist in practical application, so that the return loss is high, and the effect of low side lobe cannot be achieved.

Based on the above, the invention aims to at least solve one of the technical problems in the prior art, and provides a low-sidelobe microwave antenna and a design method thereof.

The invention is further described below with reference to the drawings and examples;

Referring to fig. 1 and 2, fig. 1 is a schematic structural view of a low-sidelobe microwave antenna provided by an embodiment of the present invention, fig. 2 is a schematic structural view of a feed source provided by an embodiment of the present invention, and the embodiment of the present invention provides a low-sidelobe microwave antenna, which includes a main reflecting surface 100, a feed source 200 and a surrounding edge 300, wherein the main reflecting surface 100 is a paraboloid of revolution, the feed source 200 is disposed at a focal point of the main reflecting surface, the feed source 200 includes a radiation source, a secondary reflecting surface 210, a circular waveguide 230 and a dielectric ring 220 disposed on a scattering plate, the surrounding edge 300 is disposed around an edge of the main reflecting surface 100 and is used for absorbing signals exceeding a receiving range of the main reflecting surface 100, and geometric parameters of the dielectric ring 220 are configured such that the direction diagram of the feed source 200 conforms to an improved generalized taylor displacement distribution, and the expression of the improved generalized taylor displacement distribution is: Wherein r _b is the center shielding radius, B1 is a constant greater than 0.45, and J0 is the value of the first zero point of the 0 th order bessel function.

In some embodiments, the secondary reflecting surface 210 is positioned in front of the primary reflecting surface 100, and is used for secondarily reflecting the electromagnetic waves converged by the primary reflecting surface 100, optimizing the directivity of the antenna, further focusing or diffusing the beam of the primary reflecting surface 100 to increase the gain or adjust the beam width, a radiation source for generating or receiving the electromagnetic waves, and a splash plate mounted on the periphery of the radiation source or on a metal/dielectric structure in the feed system, for controlling the scattering direction of the electromagnetic waves, suppressing side lobes or adjusting the shape of the main beam.

Wherein the secondary reflecting surface 210 is fixed in front of the primary reflecting surface 100 by a support rod, and the axes of the secondary reflecting surface and the primary reflecting surface are aligned strictly. The position of the secondary reflecting surface 210 is determined according to the focal length and hyperboloid eccentricity of the primary reflecting surface 100, for example, the distance can be 0.2 to 0.3 times of the focal length of the primary reflecting surface 100, the radiation source is arranged at the central position of the feed source 200, such as the opening end of a horn antenna, the splash plate is used as a part of the feed source 200 and is arranged around the radiation source, in addition, the splash plate can be fixed at the front end of the feed source 200 through a flange or a buckle structure, the geometric shape of a medium ring 220 arranged on the splash plate directly influences the directional diagram of the feed source 200, and the energy distribution of the primary/secondary reflecting surface 210 is regulated.

It can be understood that the signal emission process includes the steps of generating electromagnetic waves by the radiation source, adjusting the wave front phase/amplitude by the splash plate, guiding the electromagnetic waves to the secondary reflection surface 210 through the feed source 200, secondarily reflecting the electromagnetic waves to the primary reflection surface 100 by the secondary reflection surface 210, directionally radiating the wave beams to the space by the primary reflection surface 100, receiving external electromagnetic waves by the primary reflection surface 100, focusing the external electromagnetic waves to the secondary reflection surface 210, reflecting the external electromagnetic waves to the feed source 200 by the secondary reflection surface 210, suppressing stray signals by the splash plate, and transmitting the signals to the rear-end circuit by the radiation source, wherein the splash plate can enable the directional diagram of the feed source 200 to conform to Taylor distribution through the inclined plane formed by the dielectric ring 220, and reduce the sidelobe level.

It can be understood that the microwave antenna includes a main reflecting surface 100, a feed source 200 and a surrounding edge 300, wherein the main reflecting surface 100 adopts a rotating paraboloid structure, the feed source 200 is arranged at a focus, the feed source 200 is composed of a radiation source, a secondary reflecting surface 210, a circular waveguide 230 and a dielectric ring 220 on a splash plate, geometric parameters of the dielectric ring 220 are optimized based on improved generalized taylor displacement distribution, and mathematical expressions are as follows: Wherein r _b is the central shielding radius, B1 is a constant larger than 0.45, J0 is the value of the first zero point of the 0 th order Bessel function, and the distribution can enable the feed source 200 direction diagram to be strictly attached to Taylor distribution in a 0.2-1-time radius area by adjusting the geometric shape of the dielectric ring 220, such as a multi-step inclined plane design, so that the side lobe level is controlled below-40 dB, the return loss is reduced below-20 dB, and the performance index of the antenna is effectively improved.

In some embodiments, it can be understood that in the improved generalized taylor displacement distribution parameter setting, rb=0.1r represents that the central shielding radius is set to be 0.1 times of the radius, so as to avoid that the central area of the main reflecting surface 100 is shielded too much, and reduce gain loss caused by shielding of the feed source 200, b1=0.5 represents that the gradient of the constant control amplitude distribution is set to be 0.5, smooth transition can be realized in the area from 0.2R to 1R, severe fluctuation of the directional diagram is avoided, and the range from 0.2R to 1R represents that the main distribution area of the energy of the covering side lobes, and the radiation field amplitude is precisely controlled by adjusting the geometric shape, such as thickness and bevel angle, of the medium ring 220 in the area.

In some embodiments, the edge of the dielectric ring 220 is processed into an inclined plane, and the inclination angle can be configured according to the amplitude gradual change requirement of the taylor distribution, so that the taylor distribution requires the amplitude of the feed source 200 direction diagram to be gradually increased or decreased in a specific area so as to inhibit side lobes, and it is worth noting that the inclined plane formed by the processing of the edge of the dielectric ring 220 can enable the thickness of the dielectric in signal paths with different radiation angles to be uniformly increased or decreased, so that the reflected signals can be reduced, the return loss is reduced, and the fluctuation of the feed source 200 direction diagram is not easy to occur, so that the curve is more fit with the generalized taylor displacement distribution, and the technical effect of low cross polarization and low side lobes is improved.

In some embodiments, the bevel achieves this by having a small bevel angle, such as 5 °, if the Taylor distribution requires a low center region amplitude and a high edge, tapering the thickness of the media from the center outward, directing electromagnetic wave energy toward the edge, and a large bevel angle, such as 15 °, if the distribution requires a high center amplitude and a low edge, thickening the thickness of the media from the center outward, suppressing edge radiated energy.

In some embodiments, the first wave absorbing material on the inner side of the surrounding edge 300 may be a multi-layer composite structure, such as an outer conductive carbon fiber layer, an intermediate ferrite layer, and an inner flexible foam layer, where the outer conductive carbon fiber layer is used to reflect high frequency clutter, the intermediate ferrite layer is used to absorb 6GHz to 40GHz signals, and the inner flexible foam layer is used to buffer vibration, and it is understood that, corresponding to fig. 1, by tuning the secondary reflection surface and forming the edge of the dielectric ring into a slope, the pattern is the lowest when 165 degrees, where 180 degrees corresponds to the center of the primary reflection surface, 160 degrees corresponds to about 0.2 times the radius, 130 degrees reaches the highest, and then starts to drop at 105 degrees, which conforms to the range of the taylor distribution, and for signals exceeding 60 degrees, the method of adding wave absorbing material on the surrounding edge is adopted to absorb, and reduce the cross polarization while reducing the secondary lobe.

Further, attaching a wave-absorbing material to the outer side of the circular waveguide 230 can prevent diffraction from reaching the technical effects of low side lobes and low cross polarization, and the second wave-absorbing material on the outer side of the circular waveguide 230 can be coated with ferrite coating along the circumference section for suppressing the diffraction field generated on the surface of the circular waveguide 230, and in addition, the thickness of the wave-absorbing material can be dynamically adjusted according to the intensity of the diffraction field, for example, a strong diffraction area such as a waveguide junction is coated with 1.5mm to 2mm, and a weak area is coated with 0.5mm to 1mm.

In some embodiments, the multi-step bevel at the edge of the dielectric ring 220 is composed of at least two levels of sub-bevels, the levels are connected by a short transition section, for example, the multi-step bevel is divided into three levels, 5 °,10 °,15 °, the length of the multi-step bevel is 10% to 20% of the sub-bevels, it being understood that different steps correspond to different frequency band wavelengths, for example, 5 ° bevel optimized low frequency band (6 GHz to 18 GHz), and 15 ° bevel optimized high frequency band (18 GHz to 40 GHz).

In some embodiments, the side lobe level of the microwave antenna is lower than-40 dB, and it can be understood that the side lobe level lower than-40 dB is the core requirement of ETSI-CLASS4, and by adopting the scheme of the invention, the improved Taylor distribution and the multi-step inclined plane are combined to control the radiation field amplitude distribution, and the surrounding edge 300 and the circular waveguide 230 wave-absorbing layer absorb stray signals directionally, the microwave antenna can realize high performance indexes of less than or equal to-40 dB, less than or equal to-35 dB in cross polarization and less than or equal to-20 dB in return loss, and the ETSI-CLASS4 level is achieved.

Referring to fig. 3, fig. 3 is a flow chart of a design method of a low sidelobe low cross polarization microwave antenna provided by an embodiment of the present invention, in some embodiments, the design method is applied to a low sidelobe microwave antenna, the microwave antenna includes a main reflecting surface, a feed source and a surrounding edge, wherein the main reflecting surface is in a rotating paraboloid structure, the feed source is arranged at a focus of the main reflecting surface, the feed source includes a radiation source, a secondary reflecting surface, a circular waveguide and a dielectric ring arranged on a splash plate, the surrounding edge is arranged around an edge of the main reflecting surface and is used for absorbing signals exceeding a receiving range of the main reflecting surface, and geometric parameters of the dielectric ring are configured to enable the feed source direction diagram to conform to an improved generalized taylor displacement distribution, and the expression of the improved generalized taylor displacement distribution is as follows: wherein r _b is the central shielding radius, B1 is a constant larger than 0.45, J0 is the value of the first zero point of the 0 th order Bessel function, and the design method comprises the following steps:

step S310, calculating amplitude distribution parameters of a feed source directional diagram based on an improved generalized Taylor displacement distribution formula;

Step S320, the geometric shape of the medium ring is adjusted according to the amplitude distribution parameters, so that the feed source directional diagram accords with the Taylor distribution corresponding to the improved generalized Taylor displacement distribution formula.

The amplitude parameter of the feed source directional diagram is calculated through an improved generalized Taylor displacement distribution formula, the amplitude gradual change of a radiation field can be accurately controlled, so that the side lobe level is restrained, the geometrical shape (such as the inclined plane angle and the thickness distribution) of a medium ring is regulated to enable the directional diagram to strictly fit the Taylor distribution, the directional diagram fluctuation is reduced, the side lobe level is ensured to be stably lower than-40 dB, and the cross polarization level is lower than-35 dB.

In some embodiments, electromagnetic simulation software (e.g., CST or HFSS) may be used to formulate And (3) performing parametric modeling, wherein the input R _b is a central shielding radius, the B1 is a constant larger than 0.45, a target amplitude distribution curve is generated, and the inclined plane angle and the debugging range (0.2R to 1R) of the medium ring are adjusted through optimization algorithms such as a genetic algorithm, so that errors of a simulation directional diagram and Taylor distribution are reduced.

In some embodiments, after adjusting the geometry of the dielectric ring, the design method further comprises attaching a first wave-absorbing material to the inside of the peripheral edge and uniformly coating a second wave-absorbing material circumferentially on the outside of the circular waveguide.

Referring to fig. 4, fig. 4 is a flowchart illustrating steps for adjusting the geometry of a dielectric ring according to an embodiment of the present invention, and in some embodiments, after adjusting the geometry of the dielectric ring, the design method further includes the steps of:

step S410, verifying whether the side lobe level and the cross polarization of the microwave antenna meet preset standards or not through experiments;

in step S420, in case the preset criterion is not met, the geometry of the media ring is adjusted again based on the preset rule.

In some embodiments, after verifying whether the sidelobe level and the cross polarization of the microwave antenna meet the preset standard through experiments, the design method further comprises the step of adjusting the inclined plane angle of the edge of the medium ring according to the result of the experiment verification under the condition that the sidelobe level and the cross polarization of the microwave antenna do not meet the preset standard, so that the thickness of the medium in the signal path is uniformly changed to optimize the fitting degree of the feed source directional diagram and the Taylor distribution, wherein the sidelobe level stability is less than or equal to-40 dB, the cross polarization is less than or equal to-35 dB through the experiment verification and the feedback adjustment, and the ETSI CLASS standard is met.

Referring to fig. 5, fig. 5 is a feed pattern provided by an embodiment of the present invention, and in some embodiments, fig. 5 shows a feed pattern (far field gain absolute value, phi=90°) of a microwave antenna according to an embodiment of the present invention, as shown, in a range of Theta angle 0 ° to 180 °, a main lobe gain peaks about 10dB around theta=0°, and a main lobe width (half power beam width) is about 20 °, exhibiting excellent directional radiation capability. In addition, the gain value is maintained below-35 dB near theta=90° (cross polarization sensitive area), which shows that the synergism of the surrounding edge wave absorbing material and the circular waveguide coating effectively inhibits cross polarization interference, the pattern data is measured by a three-dimensional near field test system, the test distance is 3 times of wavelength, the scanning angle covers-180 DEG to 180 DEG, and the deviation from the simulation result is less than +/-2 dB, thereby further proving the reliability of the design method and the broadband stability of the antenna (6 GHz to 40 GHz).

Claims (10)

1. A low side lobe microwave antenna, the microwave antenna comprising:

A main reflecting surface, a feed source and a surrounding edge;

The main reflecting surface is of a rotary paraboloid structure, the feed source is arranged at the focus of the main reflecting surface, the feed source comprises a radiation source, a secondary reflecting surface, a circular waveguide and a medium ring arranged on a splash plate, the surrounding edge is arranged around the edge of the main reflecting surface and used for absorbing signals exceeding the receiving range of the main reflecting surface, the geometric parameters of the medium ring are configured to enable the feed source pattern to conform to improved generalized Taylor displacement distribution, and the expression of the improved generalized Taylor displacement distribution is as follows:

Wherein r _b is the center shielding radius, B1 is a constant greater than 0.45, and J0 is the value of the first zero point of the 0 th order bessel function.

2. The low sidelobe microwave antenna of claim 1, wherein the edges of the dielectric ring form a bevel, the bevel being inclined at an angle configured such that the amplitude variation of the feed pattern conforms to an increasing or decreasing trend of the taylor distribution.

3. The low side lobe microwave antenna of claim 1 wherein in the modified generalized taylor displacement profile r _b is set to 0.1 times radius and B1 is set to 0.5, the tuning range of the dielectric ring covers an annular area of 0.2 to 1 times radius.

4. The low-sidelobe microwave antenna of claim 1, wherein a first wave absorbing material is added to the inner side of the surrounding edge, the first wave absorbing material is used for absorbing sidelobe signals outside 60 degrees, and a second wave absorbing material is uniformly coated on the outer side of the circular waveguide along the circumferential direction.

5. The low-sidelobe microwave antenna of claim 2, wherein the inclined plane of the edge of the dielectric ring is a multi-step inclined plane, the multi-step inclined plane is composed of at least two stages of sub-inclined planes with different inclined angles, and the sub-inclined planes of each stage are connected through a short transition section to integrally form a sectional gradual change structure.

6. The low side lobe microwave antenna of any one of claims 1 to 4 wherein the side lobe level of the microwave antenna is below-40 dB.

7. A design method of a low-sidelobe low-cross-polarization microwave antenna is characterized by being applied to the low-sidelobe microwave antenna, wherein the microwave antenna comprises a main reflecting surface, a feed source and a surrounding edge, the main reflecting surface is of a rotary paraboloid structure, the feed source is arranged at a focus of the main reflecting surface, the feed source comprises a radiation source, a secondary reflecting surface, a circular waveguide and a dielectric ring arranged on a splash plate, the surrounding edge is arranged around the edge of the main reflecting surface and is used for absorbing signals exceeding the receiving range of the main reflecting surface, and geometric parameters of the dielectric ring are configured to enable a feed source directional diagram to conform to improved generalized Taylor displacement distribution, and the expression of the improved generalized Taylor displacement distribution is as follows: Wherein r _b is the central shielding radius, B1 is a constant greater than 0.45, J0 is the value of the first zero point of the 0 th order Bessel function;

the design method comprises the following steps:

Calculating amplitude distribution parameters of the feed source directional diagram based on the improved generalized Taylor displacement distribution formula;

And adjusting the geometric shape of the medium ring according to the amplitude distribution parameters, so that the feed source directional diagram accords with the Taylor distribution corresponding to the improved generalized Taylor displacement distribution formula.

8. The method of designing a low-side-lobe, low-cross-polarization microwave antenna of claim 7, wherein said adjusting said geometry of said dielectric loop is followed by:

And a first wave-absorbing material is added to the inner side of the surrounding edge, the first wave-absorbing material is used for absorbing side lobe signals beyond 60 degrees, and a second wave-absorbing material is uniformly coated on the outer side of the circular waveguide along the circumferential direction.

9. The method of designing a low-side-lobe, low-cross-polarization microwave antenna of claim 7, wherein said adjusting said geometry of said dielectric loop is followed by:

Experiments prove whether the side lobe level and the cross polarization of the microwave antenna meet preset standards or not;

and in case of not meeting the preset standard, readjusting the geometric shape of the medium ring based on preset rules.

10. The design method according to claim 9, wherein after verifying through experiments whether the side lobe level and the cross polarization of the microwave antenna meet preset standards, the design method further comprises:

And under the condition that the preset standard is not met, adjusting the inclined plane angle of the edge of the medium ring according to the experimental verification result, so that the thickness of the medium in the signal path is uniformly changed, and the fit degree of the feed source directional diagram and the Taylor distribution is optimized.