CN115832695A

CN115832695A - Dual-mode dual-circularly-polarized antenna array

Info

Publication number: CN115832695A
Application number: CN202211536085.6A
Authority: CN
Inventors: 董春丽; 黄季甫; 陆云龙; 尤阳; 沈书豪
Original assignee: Ningbo University
Current assignee: Ningbo University
Priority date: 2022-12-02
Filing date: 2022-12-02
Publication date: 2023-03-21

Abstract

The invention discloses a dual-mode dual-circularly polarized antenna array, which comprises a dual-mode feed network and a radiation network which are stacked from bottom to top, wherein the dual-mode feed network is used for transmitting electromagnetic waves in forms of TE10 modes and TEM modes input at the dual-mode feed network to the radiation network; the radiation network is used for radiating the electromagnetic wave transmitted to the radiation network to free space, and the dual-mode feed network is a hybrid feed network based on a hollow waveguide structure and a SISL structure; the radiation network is a mixed radiation network based on a clapboard structure and a step gradient horn structure; the high-gain linear array has the advantages of low profile, low side lobe and simple structure, and can be applied to high-gain scenes.

Description

Dual-mode dual-circularly-polarized antenna array

Technical Field

The present invention relates to a circularly polarized antenna array, and more particularly, to a dual-mode dual circularly polarized antenna array.

Background

Circularly Polarized (CP) antennas are widely used in Global Positioning Systems (GPS), satellites and radar scenarios due to their good multipath interference resistance and convenient polarization matching, and in addition, CP antennas have the advantages of high flexibility, better mobility, reduced multipath reflections in transmission and reception, etc., making them increasingly interesting to researchers. The partition plate circular polarizer is formed by inserting the stepped diaphragm into the square hollow waveguide, can simultaneously form double circular polarization, has the advantages of compact structure and easiness in manufacturing, and is very suitable for array application. However, if such a diaphragm circular polarizer is used directly as a large-scale array of radiating elements, the layout of the feed network is difficult to achieve, especially for the millimeter-wave band. To overcome this difficulty, it is usually chosen to add a step-type coupled resonator to the diaphragm polarizer to obtain sufficient space for designing the feed network, but this in turn increases its profile height, which also results in the generation of grating lobes.

The two-layer parallel feed network is arranged in the reported baffle plate dual circularly polarized antenna array so far, and when a large-scale array is arranged, the plane of the antenna is very high, and the problem of high side lobe is also caused. In document 1 ("a wide Dual circular Polarized Full-corporation wave Array Antenna tertiary Triple-Antenna antennas"), a diaphragm Dual Circularly Polarized Antenna Array is disclosed, which has a high planar surface reaching 50.6mm (5.06 wavelengths) and high side lobes, and the structure of the radiating portion is complex, the gain is low, and the efficiency is not very ideal. Therefore, the baffle plate dual circularly polarized antenna can hardly meet the actual requirement of a microwave communication link, and the applicability still needs to be improved.

Disclosure of Invention

The invention aims to provide a dual-mode dual-circularly polarized antenna array which has a lower profile, a lower side lobe and a simple structure and can be applied to a high-gain scene.

The technical scheme adopted by the invention for solving the technical problems is as follows: a dual-mode dual-circularly polarized antenna array comprises a dual-mode feed network and a radiation network which are stacked from bottom to top, wherein the dual-mode feed network is used for transmitting electromagnetic waves in TE10 modes and TEM modes input at the dual-mode feed network to the radiation network; the radiation network is used for radiating the electromagnetic wave transmitted to the radiation network to free space, and the dual-mode feed network is a hybrid feed network based on a hollow waveguide structure and a SISL structure; the radiation network is a mixed radiation network based on a clapboard structure and a step gradient horn structure.

The radiation network comprises three metal plates and 16 radiation units arranged on the three metal plates; the three metal plates are respectively called a first metal plate, a second metal plate and a third metal plate; the second metal plate is positioned below the first metal plate, the third metal plate is positioned below the second metal plate, the first metal plate, the second metal plate and the third metal plate are square plates and have the same size, the first metal plate, the second metal plate and the third metal plate are vertically aligned and laminated together, the length direction of each metal plate is taken as the left-right direction, the width direction is taken as the front-back direction, and the thickness direction is taken as the vertical direction; each radiation unit comprises a first radiation component, a second radiation component and a third radiation component; the first radiation assembly comprises four cylindrical hollow waveguides arranged on the first metal plate, and the four cylindrical hollow waveguides are respectively called a first cylindrical hollow waveguide, a second cylindrical hollow waveguide, a third cylindrical hollow waveguide and a fourth cylindrical hollow waveguide; the radiuses of the four cylindrical hollow waveguides are equal, the four cylindrical hollow waveguides vertically penetrate through the first metal plate, the first cylindrical hollow waveguides, the second cylindrical hollow waveguides, the third cylindrical hollow waveguides and the fourth cylindrical hollow waveguides are uniformly distributed at intervals in a 2-row 2-column mode, the row direction of the four cylindrical hollow waveguides is along the front-back direction, the column direction of the four cylindrical hollow waveguides is along the left-right direction, the first cylindrical hollow waveguides are located in a 1 st-row 1 st-column, the second cylindrical hollow waveguides are located in a 2 nd-row 1 st-column, the third cylindrical hollow waveguides are located in a 1 st-row 2 nd-column, the fourth cylindrical hollow waveguides are located in a 2 nd-row 2 nd-column, the central distance between the first cylindrical hollow waveguides and the second cylindrical hollow waveguides is 12.5mm, and the central distance between the first cylindrical hollow waveguides and the third cylindrical hollow waveguides is 12.5mm, the center distance between the fourth cylindrical hollow waveguide and the second cylindrical hollow waveguide is 12.5mm, the center distance between the third cylindrical hollow waveguide and the fourth cylindrical hollow waveguide is 12.5mm, the first cylindrical hollow waveguide and the second cylindrical hollow waveguide are symmetrical front and back, the plane where the front and back symmetry planes are located is called a first symmetry plane, the first cylindrical hollow waveguide and the third cylindrical hollow waveguide are symmetrical left and right, the plane where the left and right symmetry planes are located is called a second symmetry plane, the intersection of the first symmetry plane and the second symmetry plane is the center line of the first radiation component, the plane where the symmetry plane of the first cylindrical hollow waveguide along the front and back direction is located is called a third symmetry plane, the plane where the symmetry plane of the first cylindrical hollow waveguide along the left and right direction is located is called a fourth symmetry plane, the straight line where the center line of the first radiation assembly is located is called the center of the radiation unit; the second radiation assembly comprises a three-stage step gradient horn arranged on the second metal plate, the three-stage step gradient horn is composed of three square hollow waveguides, and the three square hollow waveguides are respectively called a first square hollow waveguide, a second square hollow waveguide and a third square hollow waveguide; the first square hollow waveguide, the second square hollow waveguide and the third square hollow waveguide are distributed from top to bottom in sequence, the upper end surfaces of the first square hollow waveguide, the second square hollow waveguide and the third square hollow waveguide are square, the upper end surface of the first square hollow waveguide is flush with the upper end surface of the second metal plate, and the central line of the first square hollow waveguide in the vertical direction and the central line of the first radiation assembly are positioned on the same straight line; four edges of the first square hollow waveguide are chamfered along the vertical direction, the plane of the front end surface of the first square hollow waveguide is positioned on the front side of the fourth symmetrical surface, the distance between the four edges is larger than the radius of the first hollow waveguide, the upper end surface of the second square hollow waveguide is connected with the lower end surface of the first square hollow waveguide in a joint state, the center line of the second square hollow waveguide along the vertical direction and the center line of the first square hollow waveguide along the vertical direction are positioned on the same straight line, the side length of the second square hollow waveguide is smaller than that of the first square hollow waveguide, the height of the second square hollow waveguide along the vertical direction is smaller than that of the first square hollow waveguide, the plane of the front end surface of the second square hollow waveguide is positioned on the front side of the fourth symmetrical surface, and the distance between the two edges is smaller than the radius of the first cylindrical hollow waveguide, the upper end surface of the third square hollow waveguide is connected with the lower end surface of the second square hollow waveguide in a joint state, the vertical center line of the third square hollow waveguide and the vertical center line of the second square hollow waveguide are positioned on the same straight line, the lower end surface of the third square hollow waveguide is flush with the lower end surface of the second metal plate, the side length of the third square hollow waveguide is smaller than that of the second square hollow waveguide, the vertical height of the third square hollow waveguide is larger than that of the second square hollow waveguide, the plane where the front end surface of the third square hollow waveguide is positioned at the rear side of the fourth symmetrical surface, and the distance between the front end surface and the plane is smaller than the radius of the first cylindrical hollow waveguide (ii) a The third radiation assembly comprises a first square groove and a five-stage metal ladder which are arranged on the third metal plate; the first square groove vertically penetrates through the third metal plate, the central line of the first square groove along the vertical direction and the central line of the third square hollow waveguide along the vertical direction are positioned on the same straight line, the front end surface of the first square groove and the front end surface of the third square hollow waveguide are positioned on the same plane, the rear end surface of the first square groove and the rear end surface of the third square hollow waveguide are positioned on the same plane, the left end surface of the first square groove and the left end surface of the third square hollow waveguide are positioned on the same plane, the right end surface of the first square groove and the right end surface of the third square hollow waveguide are positioned on the same plane, the five-stage metal ladder comprises five rectangular metal blocks which are respectively called as a first rectangular metal block, a second rectangular metal block, a third rectangular metal block, a fourth rectangular metal block and a fifth rectangular metal block, the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are sequentially arranged in the first rectangular groove from front to back, the front end face of the first rectangular metal block is fixedly connected with the front end face of the first rectangular groove and is in a joint state, the front end face of the second rectangular metal block is fixedly connected with the back end face of the first rectangular metal block and is in a joint state, the front end face of the third rectangular metal block is fixedly connected with the back end face of the second rectangular metal block and is in a joint state, the front end face of the fourth rectangular metal block is fixedly connected with the back end face of the third rectangular metal block and is in a joint state, the front end face of the fifth rectangular metal block is fixedly connected with the back end face of the fourth rectangular metal block and is in a joint state, the rear end face of the fifth rectangular metal block is fixedly connected with the rear end face of the first square groove and is in a joint state, the left end faces of the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are positioned on the same plane, the right end faces of the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are positioned on the same plane, the lower end faces of the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are positioned on the same plane with the lower end face of the first square groove, the distance from the right end surface of the first rectangular metal block to the right end surface of the first rectangular groove is equal to the distance from the left end surface of the first rectangular metal block to the left end surface of the first rectangular groove, the length of the first rectangular metal block in the left-right direction is smaller than the length of the first rectangular groove in the left-right direction, the upper end surface of the first rectangular metal block and the upper end surface of the first rectangular groove are positioned on the same plane, the width of the second rectangular metal block in the front-back direction is smaller than the width of the first rectangular metal block in the front-back direction, the height of the second rectangular metal block in the up-down direction is smaller than the height of the first rectangular metal block in the up-down direction, the width of the third rectangular metal block in the front-back direction is larger than the width of the second rectangular metal block in the front-back direction, and the height of the third rectangular metal block in the up-down direction is smaller than the height of the second rectangular metal block in the up-down direction, the width of the fourth rectangular metal block along the front-back direction is larger than that of the third rectangular metal block along the front-back direction, and the height of the fourth rectangular metal block along the up-down direction is smaller than that of the third rectangular metal block along the up-down direction; the width of the fifth rectangular metal block along the front-back direction is smaller than the width of the fourth rectangular metal block along the front-back direction, and the height of the fifth rectangular metal block along the up-down direction is smaller than the height of the fourth rectangular metal block along the up-down direction; a first input port of the radiation unit is defined by the front end of the lower end surface of the first square groove, the rear end of the lower end surface of the first square groove, the left end of the lower end surface of the first square groove and the left end of the lower end surface of the five-level metal ladder, a second input port of the radiation unit is defined by the front end of the lower end surface of the first square groove, the rear end of the lower end surface of the first square groove, the right end of the lower end surface of the first square groove and the right end of the lower end surface of the five-level metal ladder, and the upper end surfaces of the four cylindrical hollow waveguides jointly form an output port of the radiation unit; the 16 radiation units are uniformly distributed at intervals in a 4-row and 4-column mode, the row direction of the radiation units is along the front-back direction, the column direction of the radiation units is along the left-right direction, the distance between the central lines of every two adjacent radiation units in the same row is 25mm, and the distance between the central lines of every two adjacent radiation units in the same column is 25mm.

The dual-mode feed network comprises two metal plates, a dielectric plate, a sixteen-power divider based on hollow waveguides and sixteen mode separators, wherein the two metal plates are called a fourth metal plate and a fifth metal plate, the fourth metal plate, the dielectric plate and the fifth metal plate are sequentially stacked from top to bottom, the lengths of the fourth metal plate, the dielectric plate and the fifth metal plate in the left-right direction are equal, the lengths of the fourth metal plate, the dielectric plate and the fifth metal plate in the front-back direction are equal, the fourth metal plate is positioned below the third metal plate, the upper end face of the fourth metal plate is attached to the lower end face of the third metal plate, the left end face of the fourth metal plate is flush with the left end face of the third metal plate, the right end face of the fourth metal plate is flush with the right end face of the third metal plate, the front end face of the fourth metal plate is flush with the front end face of the third metal plate, and the rear end face of the fourth metal plate is flush with the rear end face of the third metal plate; a first copper-clad layer is attached to the upper surface of the dielectric plate, the front end surface of the first copper-clad layer is flush with the front end surface of the dielectric plate, the rear end surface of the first copper-clad layer is flush with the rear end surface of the dielectric plate, the left end surface of the first copper-clad layer is flush with the left end surface of the dielectric plate, the right end surface of the first copper-clad layer is flush with the right end surface of the dielectric plate, a second copper-clad layer is attached to the lower surface of the dielectric plate, the front end surface of the second copper-clad layer is flush with the front end surface of the dielectric plate, the rear end surface of the second copper-clad layer is flush with the rear end surface of the dielectric plate, the left end surface of the second copper-clad layer is flush with the left end surface of the dielectric plate, and the right end surface of the second copper-clad layer is flush with the right end surface of the dielectric plate; the hollow waveguide-based sixteen-power divider has an input port and sixteen output ports, the thickness direction of the hollow waveguide-based sixteen-power divider is along the up-down direction, the hollow waveguide-based sixteen-power divider is divided into an upper half structure and a lower half structure along the thickness direction of the hollow waveguide-based sixteen-power divider, the upper half structure of the hollow waveguide-based sixteen-power divider is disposed on the fourth metal plate, the upper half structure of the hollow waveguide-based sixteen-power divider is referred to as a first feeding portion, the lower half structure of the hollow waveguide-based sixteen-power divider is disposed on the fifth metal plate, the lower half structure of the hollow waveguide-based sixteen-power divider is referred to as a second feeding portion, the first feeding portion and the second feeding portion are completely aligned up and down, and if the second feeding portion moves downward, the lower feeding portion and the second feeding portion are spliced to form a complete hollow waveguide-based sixteen-power divider structure; the first copper-clad layer is provided with a first groove with the same contour as a sixteen-one power divider based on a hollow waveguide, the second copper-clad layer is provided with a second groove with the same contour as a sixteen-one power divider based on the hollow waveguide, if the first groove moves downwards, the first copper-clad layer and the second copper-clad layer are completely overlapped, the first feeding part moves downwards to enter the first groove and completely falls inside the first groove, if the second feeding part moves upwards to enter the second groove and completely falls inside the second groove, the first metalized through holes sequentially penetrate through the first copper-clad layer, the dielectric plate and the second copper-clad layer from top to bottom, the first metalized through holes surround a sixteen-one power divider contour area, and if the first feeding part moves downwards, the first metalized through holes completely enter the sixteen power divider contour area; the outline area of the divide-by-sixteen power divider surrounded by the plurality of first metalized through holes is called a first area, the input port of the first area corresponding to the divide-by-sixteen power divider is used as the input port of the first area, the sixteen output ports of the first area corresponding to the divide-by-sixteen power divider are used as the sixteen output ports of the first area, and the first area is provided with one input port and sixteen output ports; the first feeding part and the second feeding part form a feeding network based on a hollow waveguide structure, the first feeding part is provided with the upper half parts of the input port and the sixteen output ports of the one-sixteen power divider based on the hollow waveguide, and the upper half parts of the input port and the sixteen output ports of the one-sixteen power divider based on the hollow waveguide are used as one input port and sixteen output ports of the first feeding part; the second feeding part is provided with the lower half parts of the input port and the sixteen output ports of the hollow waveguide-based one-sixteen power divider, and the lower half parts of the input port and the sixteen output ports of the hollow waveguide-based one-sixteen power divider are used as one input port and sixteen output ports of the second feeding part; an input port of the first feeding part and an input port of the second feeding part jointly form an input port of the feeding network based on the hollow waveguide structure; sixteen output ports of the first feeding part and sixteen output ports of the second feeding part are in one-to-one correspondence up and down to jointly form sixteen output ports of the feeding network based on the hollow waveguide structure; the feed network based on the hollow waveguide structure is provided with an input port and sixteen output ports, and is used for converting one path of electromagnetic waves in a TE10 mode, which are connected to the input port, into sixteen paths of electromagnetic waves in a TE10 mode, and outputting the electromagnetic waves at sixteen output ends in a one-to-one correspondence manner; the first feeding portion, the dielectric plate, the first copper-clad layer, the second copper-clad layer and the second feeding portion constitute a SISL-structure-based feeding network, and an input port of the first feeding portion, an input port of the second feeding portion and an input port of the first area together constitute an input port of the SISL-structure-based feeding network; sixteen output ports of the first feeding portion, sixteen output ports of the second feeding portion and sixteen output ports of the first region are in one-to-one butt joint from top to bottom to form sixteen output ports of a SISL structure-based feeding network; the feed network based on the SISL structure is provided with an input port and sixteen output ports, and is used for changing one path of electromagnetic waves in a TEM mode form accessed by the input port into sixteen paths of electromagnetic waves in a TEM mode form and outputting the electromagnetic waves at the sixteen output ports in a one-to-one correspondence manner; the structure and the size of sixteen mode separators are completely the same, and each mode separator comprises a hollow waveguide part, an anti-leakage structure, a copper-clad block and five metal columns; the hollow waveguide part comprises seven rectangular hollow waveguides which are respectively called a first rectangular hollow waveguide, a second rectangular hollow waveguide, a third rectangular hollow waveguide, a fourth rectangular hollow waveguide, a fifth rectangular hollow waveguide, a sixth rectangular hollow waveguide and a seventh rectangular hollow waveguide; the first rectangular hollow waveguide, the second rectangular hollow waveguide, the third rectangular hollow waveguide, the fourth rectangular hollow waveguide and the fifth rectangular hollow waveguide are all arranged on the fourth metal plate, and the upper end surface of the first rectangular hollow waveguide is flush with the upper end surface of the fourth metal plate; the front end face of the first rectangular hollow waveguide, the front end face of the second rectangular hollow waveguide, the front end face of the third rectangular hollow waveguide, the front end face of the fourth rectangular hollow waveguide, the front end face of the fifth rectangular hollow waveguide, the front end face of the sixth rectangular hollow waveguide and the front end face of the seventh rectangular hollow waveguide are flush; the rear end face of the first rectangular hollow waveguide, the rear end face of the second rectangular hollow waveguide, the rear end face of the third rectangular hollow waveguide, the rear end face of the fourth rectangular hollow waveguide, the rear end face of the fifth rectangular hollow waveguide, the rear end face of the sixth rectangular hollow waveguide and the rear end face of the seventh rectangular hollow waveguide are flush; the upper end surface of the first rectangular hollow waveguide is flush with the upper end surface of the fourth metal plate, the second rectangular hollow waveguide is positioned below the first rectangular hollow waveguide, the lower end surface of the first rectangular hollow waveguide is connected with the upper end surface of the second rectangular hollow waveguide in a fitting state, and the lower end surface of the second rectangular hollow waveguide is positioned above the lower end surface of the fourth metal plate; the left end face of the second rectangular hollow waveguide is positioned on the left side of the plane where the left end face of the first rectangular hollow waveguide is positioned; the right end face of the second rectangular hollow waveguide is positioned on the left side of the plane where the right end face of the first rectangular hollow waveguide is positioned; the thickness of the second rectangular hollow waveguide along the vertical direction is smaller than that of the first rectangular hollow waveguide along the vertical direction; the third rectangular hollow waveguide is positioned below the second rectangular metal waveguide, the upper end surface of the third rectangular hollow waveguide is connected with the lower end surface of the second rectangular metal waveguide, and the third rectangular hollow waveguide and the second rectangular metal waveguide are in a joint state; the lower end surface of the third rectangular hollow waveguide is flush with the lower end surface of the fourth metal plate; the left end surface of the third rectangular hollow waveguide is flush with the left end surface of the second rectangular hollow waveguide; the right end face of the third rectangular hollow waveguide is positioned on the right side of the plane where the right end face of the first rectangular hollow waveguide is positioned; the thickness of the third rectangular hollow waveguide along the vertical direction is smaller than that of the second rectangular hollow waveguide along the vertical direction; the fourth rectangular hollow waveguide and the first rectangular hollow waveguide are bilaterally symmetrical relative to the plane of the third rectangular hollow waveguide along the front-rear direction symmetry plane, and the fifth rectangular hollow waveguide and the second rectangular hollow waveguide are bilaterally symmetrical relative to the plane of the third rectangular hollow waveguide along the front-rear direction symmetry plane; the sixth rectangular hollow waveguide and the seventh rectangular hollow waveguide are both arranged on the fifth metal plate, and the upper end surface of the sixth rectangular hollow waveguide is flush with the upper end surface of the fifth metal plate; the left end surface of the sixth rectangular hollow waveguide is flush with the left end surface of the third rectangular hollow waveguide; the right end face of the sixth rectangular hollow waveguide is flush with the right end face of the third rectangular hollow waveguide; the length of the sixth rectangular hollow waveguide along the left-right direction is consistent with that of the third rectangular hollow waveguide along the left-right direction; the thickness of the sixth rectangular hollow waveguide along the vertical direction is consistent with that of the third rectangular hollow waveguide along the vertical direction; the seventh rectangular hollow waveguide is positioned below the sixth rectangular hollow waveguide, and the upper end surface of the seventh rectangular hollow waveguide is connected with the lower end surface of the sixth rectangular hollow waveguide in a joint state; the lower end surface of the seventh rectangular hollow waveguide is positioned above the lower end surface of the fifth metal plate; the left end face of the seventh rectangular hollow waveguide is positioned on the right side of the plane where the left end face of the sixth rectangular hollow waveguide is positioned; the right end face of the seventh rectangular hollow waveguide is flush with the right end face of the sixth rectangular hollow waveguide; the leakage-proof structure comprises a plurality of second metalized through holes which penetrate through the first copper-clad layer, the dielectric plate and the second copper-clad layer from top to bottom, and a rectangular area is defined by the plurality of second metalized through holes and can enter the rectangular area if the third rectangular air waveguide moves downwards; the copper-clad block comprises three rectangular copper sheets which are respectively called a first rectangular copper sheet, a second rectangular copper sheet and a third rectangular copper sheet, an opening is formed in the first copper-clad layer, the first rectangular copper sheet, the second rectangular copper sheet and the third rectangular copper sheet are positioned at the opening, the upper end faces of the first rectangular copper sheet, the second rectangular copper sheet and the third rectangular copper sheet are flush, and the lower end faces of the first rectangular copper sheet, the second rectangular copper sheet and the third rectangular copper sheet are connected with the upper end face of the dielectric plate and are in a fit state; the rear end face of the first rectangular copper sheet is flush with the rear end face of the third rectangular hollow waveguide, the front end face of the first rectangular copper sheet is positioned behind the plane where the front end face of the third rectangular hollow waveguide is positioned and on the front side of the plane where the rear end face of the third rectangular hollow waveguide is positioned, and the distance from the left end face of the first rectangular copper sheet to the plane where the left end face of the third rectangular hollow waveguide is positioned is equal to the distance from the right end face of the first rectangular copper sheet to the plane where the right end face of the third rectangular hollow waveguide is positioned; the second rectangular copper sheet is positioned on the front side of the first rectangular copper sheet, the rear end face of the second rectangular copper sheet is connected with the front end face of the first rectangular copper sheet and is in a fit state, the left end face of the second rectangular copper sheet is positioned on the left side of the plane where the left end face of the first rectangular copper sheet is positioned, the right end face of the second rectangular copper sheet is positioned on the right side of the plane where the right end face of the first rectangular copper sheet is positioned, and the distance from the plane where the left end face of the second rectangular copper sheet is positioned to the left end face of the first rectangular copper sheet is equal to the distance from the plane where the right end face of the second rectangular copper sheet is positioned to the right end face of the first rectangular copper sheet; the length of the second rectangular copper sheet in the left-right direction is greater than that of the first rectangular copper sheet in the left-right direction, the width of the second rectangular copper sheet in the front-back direction is greater than that of the first rectangular copper sheet in the front-back direction, the third rectangular copper sheet is positioned on the right side of the second rectangular copper sheet, the front end face of the third rectangular copper sheet is flush with the front end face of the second rectangular copper sheet, the left end face of the third rectangular copper sheet is connected with the right end face of the second rectangular copper sheet and is in a fit state, and the width of the third rectangular copper sheet in the front-back direction is less than that of the second rectangular copper sheet in the front-back direction; five metal columns penetrate through the first copper-clad layer, the dielectric plate and the second copper-clad layer, the upper parts of the five metal columns are positioned in the third rectangular hollow waveguide, the lower parts of the five metal columns are positioned in the sixth rectangular hollow waveguide, and the upper end surfaces of the five metal columns are flush with the upper end surface of the third rectangular hollow waveguide; the lower end surfaces of the five metal posts are flush with the lower end surface of the sixth rectangular hollow waveguide; the five metal columns are cylindrical and are respectively called a first metal column, a second metal column, a third metal column, a fourth metal column and a fifth metal column; the first metal posts, the second metal posts and the third metal posts are arranged at intervals in a row from back to front, the distance between the first metal posts and the second metal posts is not equal to the distance between the second metal posts and the third metal posts, the distance between the axis of the first metal posts and the plane where the rear end face of the third rectangular hollow waveguide is located is larger than the radius of the first metal posts, the distance between the axis of the first metal posts and the plane where the right end face of the third rectangular hollow waveguide is located is larger than the radius of the first metal posts, the distance between the axis of the third metal posts and the plane where the front end face of the third rectangular hollow waveguide is located is larger than the radius of the third metal posts, and the distance between the axis of the third metal posts and the plane where the right end face of the third rectangular hollow waveguide is located is larger than the radius of the third metal posts, the first metal column and the second metal column are located on the right side of the plane where the right end face of the second rectangular copper sheet is located and on the rear side of the plane where the rear end face of the third rectangular copper sheet is located, the third metal column is located on the front side of the plane where the front end face of the third rectangular copper sheet is located, the fourth metal column is located on the left side of the plane where the left end face of the second rectangular copper sheet is located, the distance between the axis of the fourth metal column and the plane where the left end face of the third rectangular hollow waveguide is located is larger than the radius of the fourth metal column, the distance between the axis of the fourth metal column and the plane where the front end face of the third rectangular hollow waveguide is located is larger than the radius of the fourth metal column, and the fifth metal column is located on the right front side of the fourth metal column and on the left front side of the third metal column The distance from the fifth metal column to the plane where the front end face of the third rectangular hollow waveguide is located is larger than the radius of the fifth metal column; each mode separator is provided with an input port and two output ports, and the two output ports are respectively called a first output port and a second output port; the rear end face of the third rectangular air waveguide and the rear end face of the sixth rectangular air waveguide jointly form an input port of the mode splitter, the upper end face of the first rectangular hollow waveguide serves as a first output port of the mode splitter, and the upper end face of the fifth rectangular hollow waveguide serves as a second output port of the mode splitter; the sixteen mode separators are uniformly distributed at intervals in a 4-row and 4-column mode, the row direction of the sixteen mode separators is along the front-back direction, the column direction of the sixteen mode separators is along the left-right direction, the center distance between the first rectangular hollow waveguides of every two adjacent mode separators in the same row is 25mm, and the center distance between the first rectangular hollow waveguides of every two adjacent mode separators in the same column is 25mm; the input ports of the sixteen mode splitters are connected with sixteen output ports of the feeding network based on the hollow waveguide structure or the feeding network based on the SISL structure in a one-to-one correspondence manner, the first output ports of the sixteen mode splitters are connected with the first input ports of the sixteen radiating elements in a one-to-one correspondence manner, and the second output ports 2 of the sixteen mode splitters are connected with the second input ports of the sixteen radiating elements in a one-to-one correspondence manner.

The radius of the four cylindrical hollow waveguides is 5.1mm, the side length of the second square hollow waveguide is 7mm smaller than that of the first square hollow waveguide, the height of the second square hollow waveguide in the vertical direction is 2.8mm smaller than that of the first square hollow waveguide in the vertical direction, the side length of the third square hollow waveguide is 7.3mm smaller than that of the second square hollow waveguide, the height of the third square hollow waveguide in the vertical direction is 0.2mm larger than that of the second square hollow waveguide in the vertical direction, four edges of the first square hollow waveguide in the vertical direction are chamfered, the radius of the chamfer is 3mm, the width of the second rectangular metal block in the vertical direction is 0.56mm smaller than that of the first rectangular metal block in the vertical direction, the height of the second rectangular metal block in the vertical direction is 5.85mm smaller than that of the first rectangular metal block in the vertical direction, the height of the third rectangular metal block in the vertical direction is 5.85mm larger than that of the third rectangular metal block in the vertical direction, and the height of the third rectangular metal block in the vertical direction is 3.8mm larger than that of the third rectangular metal block in the vertical direction, and the third rectangular metal block in the vertical direction is 3.25 mm larger than that of the third rectangular metal block in the vertical direction; the width of the fifth rectangular metal block along the front-back direction is 4.35mm smaller than that of the fourth rectangular metal block along the front-back direction, and the height of the fifth rectangular metal block along the up-down direction is 1.95mm smaller than that of the fourth rectangular metal block along the up-down direction; the distance between the lower end surface of the second rectangular hollow waveguide and the lower end surface of the fourth metal plate is 1.3mm; the distance between the planes of the left end surfaces of the second rectangular hollow waveguide and the first rectangular hollow waveguide is 0.2mm; the distance between the right end face of the second rectangular hollow waveguide and the plane where the right end face of the first rectangular hollow waveguide is located is 1.6mm; the thickness of the second rectangular hollow waveguide along the vertical direction is 1.05mm smaller than that of the first rectangular hollow waveguide along the vertical direction; the distance between the right end face of the third rectangular hollow waveguide and the plane where the right end face of the first rectangular hollow waveguide is located is 11mm; the thickness of the third rectangular hollow waveguide along the vertical direction is 0.15mm smaller than that of the second rectangular hollow waveguide along the vertical direction; the distance between the lower end face of the seventh rectangular hollow waveguide and the lower end face of the fifth metal plate is 2.9mm; the distance between the left end surface of the seventh rectangular hollow waveguide and the plane where the left end surface of the sixth rectangular hollow waveguide is located is 11.5mm, the distance between the front end surface of the first rectangular copper sheet and the plane where the front end surface of the third rectangular hollow waveguide is located is 7.05mm, the length of the second rectangular copper sheet in the left-right direction is 0.59mm larger than that of the first rectangular copper sheet in the left-right direction, the width of the second rectangular copper sheet in the front-back direction is 0.3mm larger than that of the first rectangular copper sheet in the front-back direction, and the width of the third rectangular copper sheet in the front-back direction is 1.43mm smaller than that of the second rectangular copper sheet in the front-back direction; the edges of the second rectangular copper sheet in the left front direction are rounded with the radius of 2.6 mm; the radii of the five metal columns are all 0.3mm.

Compared with the prior art, the dual-mode feed network is realized by a hybrid feed network based on a hollow waveguide structure and a SISL structure, the radiation network is realized by a hybrid radiation network based on a partition plate structure and a stepped gradient horn structure, five rectangular metal blocks, namely a first rectangular metal block, a second rectangular metal block, a third rectangular metal block, a fourth rectangular metal block and a fifth rectangular metal block, in each radiation unit of the radiation network form the partition plate structure, three square hollow waveguides, namely a first square hollow waveguide, a second square hollow waveguide and a third square hollow waveguide, form the stepped gradient horn structure, in the dual-mode feed network, a traditional sixteen-division power divider based on the hollow waveguides is divided into an upper half part structure and a lower half part structure along the thickness direction, the upper half part structure is used as a first feed part, the lower half part structure is used as a second feed part, meanwhile, a dielectric plate, a first copper-clad layer on the upper surface of the dielectric plate and a second copper-clad layer on the lower surface of the dielectric plate are inserted between a first feeding part and a second feeding part as base materials, a sixteen-power divider outline area is formed on the dielectric plate, the first copper-clad layer and the second copper-clad layer through a plurality of vertically penetrating first metalized through holes, so that a feeding network based on a hollow waveguide structure is formed through the first feeding part and the second feeding part, a feeding network based on a SISL structure is formed through the first feeding part, the sixteen-power divider outline area and the second feeding part, when one path of TE10 mode electromagnetic waves are input from an input port of the feeding network based on the hollow waveguide structure, the feeding network based on the hollow waveguide structure changes the TE10 mode electromagnetic waves entering the feeding network into sixteen paths of TE10 mode electromagnetic waves and correspondingly outputs the sixteen mode separators to sixteen output ports of the feeding network, the sixteen paths of electromagnetic waves in the TE10 mode are continuously transmitted through the sixteen mode separators, the first output ports of the sixteen mode separators continuously transmit the electromagnetic waves in the TE10 mode to the input ports of the sixteen radiation units, and each radiation unit converts one path of electromagnetic waves in the TE10 mode, which are input into the radiation unit, into one path of circularly polarized electromagnetic waves through the inner partition plate structure and the stepped gradient horn structure of the radiation unit and radiates the circularly polarized electromagnetic waves to a free space; when one path of electromagnetic wave in TEM mode is input from the input port of the feed network based on SISL structure, the feed network based on SISL structure changes the electromagnetic wave in TEM mode into sixteen paths of electromagnetic wave in TEM mode and outputs them to sixteen mode splitters in sixteen output ports, the sixteen paths of electromagnetic wave in TEM mode are transmitted continuously through sixteen mode splitters, the second output port of sixteen mode splitters continuously transmits the sixteen paths of electromagnetic wave in TEM mode to the second input ports of sixteen radiating elements, each radiating element changes one path of electromagnetic wave in TEM mode into another path of circularly polarized electromagnetic wave through its internal partition plate structure and stepped gradient horn structure and radiates it to free space, the dual-mode feed network of the invention realizes two-mode feed function, the feed network based on SISL structure is almost completely embedded in the feed network based on hollow waveguide structure, in addition, because TEM mode signals are transmitted by the feed network based on SISL structure, TE10 mode signals are transmitted by the feed network based on hollow waveguide structure, and the two modes have extremely high isolation, the feasibility of combining the two feed networks into one set in the dual-mode feed network is ensured, larger coupling between energy is also ensured, and the dual-circular polarization antenna has great advantages in size compared with the existing dual-circular polarization antenna fed by two independent feed networks, and simultaneously, the radiation network is designed by adopting a partition plate structure and a step gradient horn structure, the symmetry of a directional diagram is also ensured while the excellent axial ratio is ensured, therefore, the dual-mode feed network has low section and low side lobe, the antenna also has better axial ratio and stable directional diagram, has simple structure and can meet the application requirements of high gain and low cost of a satellite communication link.

Drawings

FIG. 1 is a perspective view of a dual-mode dual circularly polarized antenna array of the present invention;

fig. 2 is a perspective view of a radiating network of the dual-mode dual circularly polarized antenna array of the present invention;

FIG. 3 is an exploded view of the radiating network of the dual-mode dual circularly polarized antenna array of the present invention;

FIG. 4 is a perspective view of a radiating element of the radiating network of the dual mode dual circularly polarized antenna array of the present invention;

fig. 5 is a first exploded view of a radiating element of a radiating network of the dual-mode dual circularly polarized antenna array of the present invention;

fig. 6 is a second exploded view of the radiating elements of the radiating network of the dual-mode dual circularly polarized antenna array of the present invention;

fig. 7 is a third exploded view of the radiating elements of the radiating network of the dual-mode dual circularly polarized antenna array of the present invention;

FIG. 8 is a perspective view of a dual mode feed network of the dual mode dual circularly polarized antenna array of the present invention;

figure 9 is an exploded view of a dual mode feed network of the dual mode dual circularly polarized antenna array of the present invention;

fig. 10 is a perspective view of a mode splitter of the dual mode feed network of the dual mode dual circularly polarized antenna array of the present invention;

figure 11 is an exploded view of a mode splitter of the dual mode feed network of the dual mode dual circularly polarized antenna array of the present invention;

fig. 12 is a simulation graph of reflection coefficients of the broadband dual-polarized antenna array of the present invention;

fig. 13 is a graph of axial ratio simulation of the broadband dual-polarized antenna array of the present invention;

fig. 14 is a graph showing a simulation of gain of the wideband dual-polarized antenna array of the present invention.

Detailed Description

The invention is described in further detail below with reference to the accompanying examples.

The first embodiment is as follows: as shown in fig. 1, a dual-mode dual circularly polarized antenna array includes a dual-mode feeding network 1 and a radiation network 2 stacked in order from bottom to top, where the dual-mode feeding network 1 is configured to transmit electromagnetic waves in TE10 mode and TEM mode input thereto to the radiation network 2; the radiation network 2 is used for radiating the electromagnetic wave transmitted to the dual-mode feed network 1 to a free space, and the dual-mode feed network 1 is a hybrid feed network based on a hollow waveguide structure and a SISL structure; the radiation network 2 is a hybrid radiation network 2 based on a diaphragm structure and a stepped gradient horn structure.

Example two: this embodiment is substantially the same as the first embodiment, except that: as shown in fig. 2 to 7, the radiation network 2 includes three metal plates and 16 radiation units 7 disposed on the three metal plates; the three metal plates are respectively called a first metal plate 4, a second metal plate 5 and a third metal plate 6; the second metal plate 5 is positioned below the first metal plate 4, the third metal plate 6 is positioned below the second metal plate 5, the first metal plate 4, the second metal plate 5 and the third metal plate 6 are square plates and have the same size, the first metal plate 4, the second metal plate 5 and the third metal plate 6 are vertically aligned and stacked together, the first metal plate 4, the second metal plate 5 and the third metal plate 6 are integrally formed, the length direction of each metal plate is taken as the left-right direction, the width direction is taken as the front-back direction, and the thickness direction is taken as the up-down direction; each radiation unit 7 includes a first radiation member, a second radiation member, and a third radiation member; the first radiation component comprises four cylindrical hollow waveguides arranged on the first metal plate 4, and the four cylindrical hollow waveguides are respectively called a first cylindrical hollow waveguide 8, a second cylindrical hollow waveguide 9, a third cylindrical hollow waveguide 10 and a fourth cylindrical hollow waveguide 11; the radiuses of the four cylindrical hollow waveguides are equal and are all 5.1mm, the four cylindrical hollow waveguides vertically penetrate through the first metal plate 4, the first cylindrical hollow waveguide 8, the second cylindrical hollow waveguide 9, the third cylindrical hollow waveguide 10 and the fourth cylindrical hollow waveguide 11 are uniformly distributed at intervals in a 2-row and 2-column mode, the row direction of the hollow waveguide is along the front-back direction, the column direction is along the left-right direction, the first cylindrical hollow waveguide 8 is positioned in the 1 st row and the 1 st column of the 1 st row, the second cylindrical hollow waveguide 9 is positioned in the 1 st row and the 1 st column of the 2 nd row, the third cylindrical hollow waveguide 10 is positioned in the 1 st row and the 2 nd column of the 1 st row, the fourth cylindrical hollow waveguide 11 is positioned in the 2 nd column of the 2 nd row, the central distance between the first cylindrical hollow waveguide 8 and the second cylindrical hollow waveguide 9 is 12.5mm, the central distance between the first cylindrical hollow waveguide 8 and the third cylindrical hollow waveguide 10 is 12.5mm, the central distance between the fourth cylindrical hollow waveguide 11 and the second cylindrical hollow waveguide 9 is 12.5mm, and the central distance between the third cylindrical hollow waveguide 10 and the fourth cylindrical hollow waveguide 11 is 12.5mm, the first cylindrical hollow waveguide 8 and the second cylindrical hollow waveguide 9 are symmetrical back and forth, the plane where the front and back symmetrical surfaces are located is called a first symmetrical surface, the first cylindrical hollow waveguide 8 and the third cylindrical hollow waveguide 10 are symmetrical left and right, the plane where the left and right symmetrical surfaces are located is called a second symmetrical surface, the intersection of the first symmetrical surface and the second symmetrical surface is the center line of the first radiation component, the plane where the symmetrical surface of the first cylindrical hollow waveguide 8 along the front and back directions is located is called a third symmetrical surface, the plane where the symmetrical surface of the first cylindrical hollow waveguide 8 along the left and right directions is located is called a fourth symmetrical surface, and the straight line where the center line of the first radiation component is located is called the center of the radiation unit 7; the second radiation component comprises a three-stage step gradient horn arranged on the second metal plate 5, the three-stage step gradient horn is composed of three square hollow waveguides, and the three square hollow waveguides are respectively called a first square hollow waveguide 12, a second square hollow waveguide 13 and a third square hollow waveguide 14; the first square hollow waveguide 12, the second square hollow waveguide 13 and the third square hollow waveguide 14 are distributed from top to bottom in sequence, the upper end surfaces of the first square hollow waveguide 12, the second square hollow waveguide 13 and the third square hollow waveguide 14 are square, the upper end surface of the first square hollow waveguide 12 is flush with the upper end surface of the second metal plate 5, and the central line of the first square hollow waveguide 12 in the vertical direction and the central line of the first radiation component are positioned on the same straight line; four edges of the first square hollow waveguide 12 along the vertical direction are chamfered, the radius of the chamfer is 3mm, the plane of the front end surface of the first square hollow waveguide 12 is positioned on the front side of the fourth symmetrical surface, the distance between the plane and the fourth symmetrical surface is larger than the radius of the first cylindrical hollow waveguide 8, the upper end surface of the second square hollow waveguide 13 is connected with the lower end surface of the first square hollow waveguide 12 and is in a joint state, the central line of the second square hollow waveguide 13 along the vertical direction and the central line of the first square hollow waveguide 12 along the vertical direction are positioned on the same straight line, the side length of the second square hollow waveguide 13 is smaller than that of the first square hollow waveguide 12, and is 7mm smaller, the height of the second square hollow waveguide 13 along the up-down direction is smaller than the height of the first square hollow waveguide 12 along the up-down direction, and is 2.8mm smaller, the plane of the front end surface of the second square hollow waveguide 13 is positioned at the front side of the fourth symmetrical surface, the distance between the front end surface and the fourth symmetrical surface is smaller than the radius of the first cylindrical hollow waveguide 8, the upper end surface of the third square hollow waveguide 14 is connected with the lower end surface of the second square hollow waveguide 13 and is in a joint state, the central line of the third square hollow waveguide 14 along the vertical direction and the central line of the second square hollow waveguide 13 along the vertical direction are positioned on the same straight line, the lower end surface of the third square hollow waveguide 14 is flush with the lower end surface of the second metal plate 5, the side length of the third square hollow waveguide 14 is smaller than that of the second square hollow waveguide 13, and is 7.3mm smaller, the height of the third square hollow waveguide 14 in the up-down direction is larger than that of the second square hollow waveguide 13 in the up-down direction, the size of the third hollow waveguide is 0.2mm, the plane where the front end face of the third square hollow waveguide 14 is located on the rear side of the fourth symmetrical plane, and the distance between the plane and the fourth symmetrical plane is smaller than the radius of the first cylindrical hollow waveguide 8; the third radiation component comprises a first square groove 15 and a five-stage metal ladder which are arranged on the third metal plate 6; the first square groove 15 penetrates through the third metal plate 6 up and down, the central line of the first square groove 15 along the up-down direction and the central line of the third square hollow waveguide 14 along the up-down direction are positioned on the same straight line, the front end face of the first square groove 15 and the front end face of the third square hollow waveguide 14 are positioned on the same plane, the rear end face of the first square groove 15 and the rear end face of the third square hollow waveguide 14 are positioned on the same plane, the left end face of the first square groove 15 and the left end face of the third square hollow waveguide 14 are positioned on the same plane, the right end face of the first square groove 15 and the right end face of the third square hollow waveguide 14 are positioned on the same plane, the five-stage metal ladder comprises five rectangular metal blocks which are respectively called a first rectangular metal block 16, a second rectangular metal block 17, a third rectangular metal block 18, a fourth rectangular metal block 19 and a fifth rectangular metal block 20, the first rectangular metal block 16, the second rectangular metal block 17, the third rectangular metal block 18, the fourth rectangular metal block 19 and the fifth rectangular metal block 20 are sequentially arranged in the first square groove 15 from front to back, the front end face of the first rectangular metal block 16 is fixedly connected with and in a joint state with the front end face of the first square groove 15, the front end face of the second rectangular metal block 17 is fixedly connected with and in a joint state with the back end face of the first rectangular metal block 16, the front end face of the third rectangular metal block 18 is fixedly connected with and in a joint state with the back end face of the second rectangular metal block 17, the front end face of the fourth rectangular metal block 19 is fixedly connected with and in a joint state with the back end face of the third rectangular metal block 18, the front end face of the fifth rectangular metal block 20 is fixedly connected with and in a joint state with the back end face of the fourth rectangular metal block 19, the back end face of the fifth rectangular metal block 20 is fixedly connected with and in a joint state with the back end face of the first square groove 15, the left end faces of the first rectangular metal block 16, the second rectangular metal block 17, the third rectangular metal block 18, the fourth rectangular metal block 19 and the fifth rectangular metal block 20 are positioned on the same plane, the right end faces of the first rectangular metal block 16, the second rectangular metal block 17, the third rectangular metal block 18, the fourth rectangular metal block 19 and the fifth rectangular metal block 20 are positioned on the same plane, the lower end faces of the first rectangular metal block 16, the second rectangular metal block 17, the third rectangular metal block 18, the fourth rectangular metal block 19 and the fifth rectangular metal block 20 and the lower end face of the first square groove 15 are positioned on the same plane, the distance from the right end face of the first rectangular metal block 16 to the right end face of the first square groove 15 is equal to the distance from the left end face of the first rectangular metal block 16 to the left end face of the first square groove 15, the length of the first rectangular metal block 16 in the left-right direction is smaller than the length of the first square groove 15 in the left-right direction, the upper end face of the first rectangular metal block 16 and the upper end face of the first rectangular groove 15 are located on the same plane, the width of the second rectangular metal block 17 in the front-rear direction is smaller than the width of the first rectangular metal block 16 in the front-rear direction by 0.56mm, the height of the second rectangular metal block 17 in the up-down direction is smaller than the height of the first rectangular metal block 16 in the up-down direction by 5.85mm, the width of the third rectangular metal block 18 in the front-rear direction is larger than the width of the second rectangular metal block 17 in the front-rear direction by 1.32mm, the height of the third rectangular metal block 18 in the up-down direction is smaller than the height of the second rectangular metal block 17 in the up-down direction by 5.25mm, the width of the fourth rectangular metal block 19 in the front-rear direction is larger than the width of the third rectangular metal block 18 in the front-rear direction by 3.04mm, the height of the fourth rectangular metal block 19 in the up-down direction is smaller than the height of the third rectangular metal block 18 in the up-down direction, and is 3.8mm smaller; the width of the fifth rectangular metal block 20 in the front-back direction is 4.35mm smaller than that of the fourth rectangular metal block 19 in the front-back direction, and the height of the fifth rectangular metal block 20 in the up-down direction is 1.95mm smaller than that of the fourth rectangular metal block 19 in the up-down direction; a first input port of the radiation unit 7 is defined by the front end of the lower end face of the first square groove 15, the rear end of the lower end face of the first square groove 15, the left end of the lower end face of the first square groove 15 and the left end of the lower end face of the five-level metal ladder, a second input port of the radiation unit 7 is defined by the front end of the lower end face of the first square groove 15, the rear end of the lower end face of the first square groove 15, the right end of the lower end face of the first square groove 15 and the right end of the lower end face of the five-level metal ladder, and the upper end faces of the four cylindrical hollow waveguides jointly form an output port of the radiation unit 7; the 16 radiation units 7 are uniformly distributed at intervals in a 4-row and 4-column mode, the row direction is along the front-back direction, the column direction is along the left-right direction, the distance between the center lines of every two adjacent radiation units 7 in the same row is 25mm, and the distance between the center lines of every two adjacent radiation units 7 in the same column is 25mm.

Example two: this embodiment is substantially the same as the second embodiment, except that: in this embodiment, as shown in fig. 8 to 11, the dual-mode feeding network 1 includes two metal plates, a dielectric plate 21, a sixteen power divider based on a hollow waveguide, and sixteen mode separators, where the two metal plates are referred to as a fourth metal plate 22 and a fifth metal plate 23, the fourth metal plate 22, the dielectric plate 21, and the fifth metal plate 23 are stacked in order from top to bottom, the lengths of the fourth metal plate 22, the dielectric plate 21, and the fifth metal plate 23 in the left-right direction are equal, and the lengths in the front-back direction are equal, the fourth metal plate 22 is located below the third metal plate 6, the upper end surface of the fourth metal plate 22 is attached to the lower end surface of the third metal plate 6, the left end surface of the fourth metal plate 22 is flush with the left end surface of the third metal plate 6, the right end surface of the fourth metal plate 22 is flush with the right end surface of the third metal plate 6, the front end surface of the fourth metal plate 22 is flush with the front end surface of the third metal plate 6, and the rear end surface of the fourth metal plate 22 is flush with the rear end surface of the third metal plate 6; a first copper-clad layer 24 is attached to the upper surface of the dielectric plate 21, the front end surface of the first copper-clad layer 24 is flush with the front end surface of the dielectric plate 21, the rear end surface of the first copper-clad layer 24 is flush with the rear end surface of the dielectric plate 21, the left end surface of the first copper-clad layer 24 is flush with the left end surface of the dielectric plate 21, the right end surface of the first copper-clad layer 24 is flush with the right end surface of the dielectric plate 21, a second copper-clad layer 25 is attached to the lower surface of the dielectric plate 21, the front end surface of the second copper-clad layer 25 is flush with the front end surface of the dielectric plate 21, the rear end surface of the second copper-clad layer 25 is flush with the rear end surface of the dielectric plate 21, the left end surface of the second copper-clad layer 25 is flush with the left end surface of the dielectric plate 21, and the right end surface of the second copper-clad layer 25 is flush with the right end surface of the dielectric plate 21; the hollow waveguide-based sixteen power divider has an input port and sixteen output ports, the thickness direction of the hollow waveguide-based sixteen power divider is along the up-down direction, the hollow waveguide-based sixteen power divider is divided into an upper half structure and a lower half structure along the thickness direction, the upper half structure of the hollow waveguide-based sixteen power divider is arranged on the fourth metal plate 22, the upper half structure of the hollow waveguide-based sixteen power divider is called a first feeding portion 26, the lower half structure of the hollow waveguide-based sixteen power divider is arranged on the fifth metal plate 23, the lower half structure of the hollow waveguide-based sixteen power divider is called a second feeding portion 27, the first feeding portion 26 and the second feeding portion 27 are completely aligned up and down, and if the second feeding portion 27 moves downwards, the hollow waveguide-based sixteen power divider and the second feeding portion 27 are spliced to form a complete hollow waveguide-based sixteen power divider structure; the first copper-clad layer 24 is provided with a first groove 28 with the same contour as a sixteen-one power divider based on a hollow waveguide, the second copper-clad layer 25 is provided with a second groove 29 with the same contour as a sixteen-one power divider based on a hollow waveguide, if the first groove 28 moves downwards, the first groove will be completely overlapped with the second groove 29, the first feeding portion 26 will completely fall inside the first groove 28 when moving downwards to enter the first groove 28, and if the second feeding portion 27 moves upwards to enter the second groove 29, the second feeding portion will completely fall inside the second groove 29, the first metalized through holes respectively penetrate through the first copper-clad layer 24, the dielectric plate 21 and the second copper-clad layer 25 from top to bottom in sequence, the first metalized through holes surround a sixteen-one power divider contour region, and if the first feeding portion 26 moves downwards, the first feeding portion will completely enter the sixteen-one power divider contour region; the outline area of the divide-by-sixteen power divider surrounded by the plurality of first metalized through holes is called a first area, the input port of the first area corresponding to the divide-by-sixteen power divider is used as the input port of the first area, the sixteen output ports of the first area corresponding to the divide-by-sixteen power divider are used as the sixteen output ports of the first area, and the first area is provided with one input port and sixteen output ports; the first feeding portion 26 and the second feeding portion 27 constitute a feeding network based on a hollow waveguide structure, the first feeding portion 26 has upper half portions of an input port and sixteen output ports of a sixteen-one-tenth power divider based on a hollow waveguide, and the upper half portions of the input port and the sixteen output ports of the sixteen-one-sixteenth power divider based on the hollow waveguide are used as one input port and sixteen output ports of the first feeding portion 26; the second feeding portion 27 has the lower half portions of the input port and the sixteen output ports of the sixteen-one-tenth power divider based on the hollow waveguide, and the lower half portions of the input port and the sixteen output ports of the sixteen-one-tenth power divider based on the hollow waveguide are used as one input port and sixteen output ports of the second feeding portion 27; one input port of the first feeding portion 26 and one input port of the second feeding portion 27 together constitute an input port of a feeding network based on a hollow waveguide structure; sixteen output ports of the first feeding portion 26 and sixteen output ports of the second feeding portion 27 are in one-to-one correspondence up and down, and form sixteen output ports of a feeding network based on a hollow waveguide structure; the feed network based on the hollow waveguide structure is used for converting one path of electromagnetic waves in a TE10 mode form, which are accessed by the input port, into sixteen paths of electromagnetic waves in a TE10 mode form, and the sixteen output ends of the electromagnetic waves are correspondingly output one by one; the first feeding portion 26, the dielectric plate 21, the first copper-clad layer 24, the second copper-clad layer 25, and the second feeding portion 27 constitute a SISL structure-based feeding network, and an input port of the first feeding portion 26, an input port of the second feeding portion 27, and an input port of the first area collectively constitute an input port of the SISL structure-based feeding network; sixteen output ports of the first feeding portion 26, sixteen output ports of the second feeding portion 27, and sixteen output ports of the first region are butted one by one from top to bottom, forming sixteen output ports of a SISL-structure-based feeding network; the feed network based on the SISL structure is used for converting one path of electromagnetic waves in a TEM mode accessed by the input port into sixteen paths of electromagnetic waves in a TEM mode and outputting the electromagnetic waves at sixteen output ends in a one-to-one correspondence manner; the structure and the size of the sixteen mode separators are completely the same, and each mode separator comprises a hollow waveguide part, a leakage-proof structure, a copper-clad block and five metal columns; the hollow core waveguide portion comprises seven rectangular hollow core waveguides, which are respectively referred to as a first rectangular hollow core waveguide 30, a second rectangular hollow core waveguide 31, a third rectangular hollow core waveguide 32, a fourth rectangular hollow core waveguide 33, a fifth rectangular hollow core waveguide 34, a sixth rectangular hollow core waveguide 35 and a seventh rectangular hollow core waveguide 36; the first rectangular hollow waveguide 30, the second rectangular hollow waveguide 31, the third rectangular hollow waveguide 32, the fourth rectangular hollow waveguide 33 and the fifth rectangular hollow waveguide 34 are all arranged on the fourth metal plate 22, and the upper end face of the first rectangular hollow waveguide 30 is flush with the upper end face of the fourth metal plate 22; the front end face of the first rectangular hollow waveguide 30, the front end face of the second rectangular hollow waveguide 31, the front end face of the third rectangular hollow waveguide 32, the front end face of the fourth rectangular hollow waveguide 33, the front end face of the fifth rectangular hollow waveguide 34, the front end face of the sixth rectangular hollow waveguide 35 and the front end face of the seventh rectangular hollow waveguide 36 are flush; the rear end face of the first rectangular hollow waveguide 30, the rear end face of the second rectangular hollow waveguide 31, the rear end face of the third rectangular hollow waveguide 32, the rear end face of the fourth rectangular hollow waveguide 33, the rear end face of the fifth rectangular hollow waveguide 34, the rear end face of the sixth rectangular hollow waveguide 35 and the rear end face of the seventh rectangular hollow waveguide 36 are flush; the upper end face of the first rectangular hollow waveguide 30 is flush with the upper end face of the fourth metal plate 22, the second rectangular hollow waveguide 31 is positioned below the first rectangular hollow waveguide 30, the lower end face of the first rectangular hollow waveguide 30 is connected with the upper end face of the second rectangular hollow waveguide 31 and is in a fit state, the lower end face of the second rectangular hollow waveguide 31 is positioned above the lower end face of the fourth metal plate 22, and the distance between the lower end face of the first rectangular hollow waveguide and the lower end face of the fourth metal plate 22 is 1.3mm; the left end face of the second rectangular hollow waveguide 31 is positioned on the left side of the plane where the left end face of the first rectangular hollow waveguide 30 is positioned, and the distance between the left end face and the plane is 0.2mm; the right end face of the second rectangular hollow waveguide 31 is positioned on the left side of the plane of the right end face of the first rectangular hollow waveguide 30, and the distance between the right end face and the plane is 1.6mm; the thickness of the second rectangular hollow waveguide 31 in the up-down direction is smaller than the thickness of the first rectangular hollow waveguide 30 in the up-down direction by 1.05mm; the third rectangular hollow waveguide 32 is positioned below the second rectangular metal waveguide, the upper end surface of the third rectangular hollow waveguide 32 is connected with the lower end surface of the second rectangular metal waveguide, and the third rectangular hollow waveguide and the second rectangular metal waveguide are in a joint state; the lower end surface of the third rectangular hollow waveguide 32 is flush with the lower end surface of the fourth metal plate 22; the left end surface of the third rectangular hollow waveguide 32 is flush with the left end surface of the second rectangular hollow waveguide 31; the right end face of the third rectangular hollow waveguide 32 is positioned on the right side of the plane of the right end face of the first rectangular hollow waveguide 30, and the distance between the right end face and the plane is 11mm; the thickness of the third rectangular hollow waveguide 32 in the up-down direction is smaller than that of the second rectangular hollow waveguide 31 in the up-down direction by 0.15mm; the fourth rectangular hollow waveguide 33 and the first rectangular hollow waveguide 30 are bilaterally symmetrical with respect to the plane of the symmetry plane of the third rectangular hollow waveguide 32 in the front-rear direction, and the fifth rectangular hollow waveguide 34 and the second rectangular hollow waveguide 31 are bilaterally symmetrical with respect to the plane of the symmetry plane of the third rectangular hollow waveguide 32 in the front-rear direction; the sixth rectangular hollow waveguide 35 and the seventh rectangular hollow waveguide 36 are both arranged on the fifth metal plate 23, and the upper end surface of the sixth rectangular hollow waveguide 35 is flush with the upper end surface of the fifth metal plate 23; the left end face of the sixth rectangular hollow waveguide 35 is flush with the left end face of the third rectangular hollow waveguide 32; the right end face of the sixth rectangular hollow waveguide 35 is flush with the right end face of the third rectangular hollow waveguide 32; the length of the sixth rectangular hollow waveguide 35 in the left-right direction is identical to the length of the third rectangular hollow waveguide 32 in the left-right direction; the thickness of the sixth rectangular hollow waveguide 35 in the up-down direction is the same as the thickness of the third rectangular hollow waveguide 32 in the up-down direction; the seventh rectangular hollow waveguide 36 is located below the sixth rectangular hollow waveguide 35, and the upper end surface of the seventh rectangular hollow waveguide 36 is connected with the lower end surface of the sixth rectangular hollow waveguide 35 and is in a fitting state; the lower end surface of the seventh rectangular hollow waveguide 36 is located above the lower end surface of the fifth metal plate 23, and the distance between the lower end surface and the fifth end surface is 2.9mm; the left end face of the seventh rectangular hollow waveguide 36 is positioned on the right side of the plane where the left end face of the sixth rectangular hollow waveguide 35 is positioned, and the distance between the left end face and the plane is 11.5mm; the right end face of the seventh rectangular hollow waveguide 36 is flush with the right end face of the sixth rectangular hollow waveguide 35; the leakage-prevention structure comprises a plurality of second metallized through holes 37 penetrating through the first copper-clad layer 24, the dielectric plate 21 and the second copper-clad layer 25 from top to bottom, the plurality of second metallized through holes 37 enclosing a rectangular region 38, which would enter the inside of the rectangular region 38 if the third rectangular air waveguide were moved downward; the copper-clad block comprises three rectangular copper sheets which are respectively called a first rectangular copper sheet 39, a second rectangular copper sheet 40 and a third rectangular copper sheet 41, an opening is formed in the first copper-clad layer 24, the first rectangular copper sheet 39, the second rectangular copper sheet 40 and the third rectangular copper sheet 41 are positioned at the opening, the upper end faces of the first rectangular copper sheet 39, the second rectangular copper sheet 40 and the third rectangular copper sheet 41 are flush, and the lower end faces of the first rectangular copper sheet 39, the second rectangular copper sheet 40 and the third rectangular copper sheet 41 are connected with the upper end face of the dielectric plate 21 and are in a fit state; the rear end face of the first rectangular copper sheet 39 is flush with the rear end face of the third rectangular hollow waveguide 32, the front end face of the first rectangular copper sheet 39 is positioned behind the plane where the front end face of the third rectangular hollow waveguide 32 is positioned and on the front side of the plane where the rear end face of the third rectangular hollow waveguide 32 is positioned, the distance between the front end face of the first rectangular copper sheet 39 and the plane where the front end face of the third rectangular hollow waveguide 32 is positioned is 7.05mm, and the distance between the left end face of the first rectangular copper sheet 39 and the plane where the left end face of the third rectangular hollow waveguide 32 is positioned is equal to the distance between the right end face of the first rectangular copper sheet 39 and the plane where the right end face of the third rectangular hollow waveguide 32 is positioned; the second rectangular copper sheet 40 is positioned on the front side of the first rectangular copper sheet 39, the rear end face of the second rectangular copper sheet 40 is connected with the front end face of the first rectangular copper sheet 39 and is in a fit state, the left end face of the second rectangular copper sheet 40 is positioned on the left side of the plane where the left end face of the first rectangular copper sheet 39 is positioned, the right end face of the second rectangular copper sheet 40 is positioned on the right side of the plane where the right end face of the first rectangular copper sheet 39 is positioned, and the distance between the plane where the left end face of the second rectangular copper sheet 40 is positioned and the left end face of the first rectangular copper sheet 39 is equal to the distance between the plane where the right end face of the second rectangular copper sheet 40 is positioned and the right end face of the first rectangular copper sheet 39; the length of the second rectangular copper sheet 40 in the left-right direction is 0.59mm greater than that of the first rectangular copper sheet 39 in the left-right direction, the width of the second rectangular copper sheet 40 in the front-back direction is 0.3mm greater than that of the first rectangular copper sheet 39 in the front-back direction, and the edges of the second rectangular copper sheet 40 in the left-front direction are rounded with the radius of 2.6 mm; the third rectangular copper sheet 41 is positioned on the right side of the second rectangular copper sheet 40, the front end face of the third rectangular copper sheet 41 is flush with the front end face of the second rectangular copper sheet 40, the left end face of the third rectangular copper sheet 41 is connected with the right end face of the second rectangular copper sheet 40 and is in a bonding state, and the width of the third rectangular copper sheet 41 in the front-back direction is 1.43mm smaller than the width of the second rectangular copper sheet 40 in the front-back direction; five metal posts penetrate through the first copper-clad layer 24, the dielectric plate 21 and the second copper-clad layer 25, the upper parts of the five metal posts are positioned in the third rectangular hollow waveguide 32, the lower parts of the five metal posts are positioned in the sixth rectangular hollow waveguide 35, and the upper end surfaces of the five metal posts are flush with the upper end surface of the third rectangular hollow waveguide 32; the lower end faces of the five metal posts are flush with the lower end face of the sixth rectangular hollow waveguide 35; the radiuses of the five metal columns are all 0.3mm, and the five metal columns are all cylindrical and are respectively called as a first metal column 42, a second metal column 43, a third metal column 44, a fourth metal column 45 and a fifth metal column 46; the first metal posts 42, the second metal posts 43 and the third metal posts 44 are arranged at intervals of one row from the rear to the front, and the distance between the first metal column 42 and the second metal column 43 is not equal to the distance between the second metal column 43 and the third metal column 44, the distance between the axis of the first metal column 42 and the plane of the rear end face of the third rectangular hollow waveguide 32 is greater than the radius of the first metal column 42, the distance between the axis of the first metal column 42 and the plane of the right end face of the third rectangular hollow waveguide 32 is greater than the radius of the first metal column 42, the distance between the axis of the third metal column 44 and the plane of the front end face of the third rectangular hollow waveguide 32 is greater than the radius of the third metal column 44, the distance between the axis of the third metal column 44 and the plane of the right end face of the third rectangular hollow waveguide 32 is greater than the radius of the third metal column 44, the first metal column 42 and the second metal column 43 are both located on the right side of the plane where the right end face of the second rectangular copper sheet 40 is located and on the rear side of the plane where the rear end face of the third rectangular copper sheet 41 is located, the third metal column 44 is located on the front side of the plane where the front end face of the third rectangular copper sheet 41 is located, the fourth metal column 45 is located on the left side of the plane where the left end face of the second rectangular copper sheet 40 is located, the distance between the axis of the fourth metal column 45 and the plane where the left end face of the third rectangular hollow waveguide 32 is located is larger than the radius of the fourth metal column 45, the distance between the axis of the fourth metal column 45 and the plane where the front end face of the third rectangular hollow waveguide 32 is located is larger than the radius of the fourth metal column 45, the fifth metal column 46 is located on the right front side of the fourth metal column 45 and on the left front side of the third metal column 44, and the distance between the fifth metal column 46 and the plane where the front end face of the third rectangular hollow waveguide 32 is located is larger than the radius of the fifth metal column 46; each mode separator is provided with an input port and two output ports which are respectively called a first output port and a second output port; the rear end face of the third rectangular air waveguide and the rear end face of the sixth rectangular air waveguide jointly form an input port of the mode separator, the upper end face of the first rectangular hollow waveguide 30 serves as a first output port of the mode separator, and the upper end face of the fifth rectangular hollow waveguide 34 serves as a second output port of the mode separator; the sixteen mode separators are uniformly distributed at intervals in a 4-row and 4-column mode, the row direction of the sixteen mode separators is along the front-back direction, the column direction of the sixteen mode separators is along the left-right direction, the center distance between the first rectangular hollow waveguides 30 of every two adjacent mode separators located in the same row is 25mm, and the center distance between the first rectangular hollow waveguides 30 of every two adjacent mode separators located in the same column is 25mm; the input ports of the sixteen mode splitters are connected with sixteen output ports of a feed network based on a hollow waveguide structure or a feed network based on a SISL structure in a one-to-one correspondence manner, the first output ports of the sixteen mode splitters are connected with the first input ports of the sixteen radiation units 7 in a one-to-one correspondence manner, and the second output ports 2 of the sixteen mode splitters are connected with the second input ports of the sixteen radiation units 7 in a one-to-one correspondence manner.

In the dual-mode dual-circularly polarized antenna array of the present invention, the dual-mode feed network is implemented by a hybrid feed network based on a hollow waveguide structure and a SISL structure, in each radiation unit of the radiation network, five rectangular metal blocks, namely a first rectangular metal block 16, a second rectangular metal block 17, a third rectangular metal block 18, a fourth rectangular metal block 19 and a fifth rectangular metal block 20, form a partition structure, three square hollow waveguides, namely a first square hollow waveguide 12, a second square hollow waveguide 13 and a third square hollow waveguide 14, form a stepped-change horn structure, in the dual-mode feed network, by dividing a conventional hollow waveguide-based sixteen power divider into an upper half structure and a lower half structure along the thickness direction thereof, the upper half structure serves as a first feed portion 26, and the lower half structure serves as a second feed portion 27, meanwhile, a dielectric plate 21, a first copper-clad layer 24 on the upper surface of the dielectric plate and a second copper-clad layer 25 on the lower surface of the dielectric plate are inserted between a first feeding portion 26 and a second feeding portion 27 as a base material, a sixteen power divider outline area is formed on the dielectric plate 21, the first copper-clad layer 24 and the second copper-clad layer 25 through a plurality of vertically penetrating first metalized through holes, so that a feeding network based on a hollow waveguide structure is formed through the first feeding portion 26 and the second feeding portion 27, a feeding network based on a SISL structure is formed through the first feeding portion 26, the sixteen power divider outline area and the second feeding portion 27, when one TE10 mode electromagnetic wave is input from an input port of the feeding network based on the hollow waveguide structure, the feeding network based on the hollow waveguide structure changes the TE10 mode electromagnetic wave entering the feeding network into sixteen TE10 mode electromagnetic waves and correspondingly outputs the sixteen mode separators at sixteen output ports thereof, the sixteen paths of electromagnetic waves in the TE10 mode are continuously transmitted through the sixteen mode separators, the first output ports of the sixteen mode separators continuously transmit the electromagnetic waves in the TE10 mode to the input ports of the sixteen radiation units, and each radiation unit converts one path of electromagnetic waves in the TE10 mode, which are input into the radiation unit, into one path of circularly polarized electromagnetic waves through the inner partition plate structure and the stepped gradient horn structure of the radiation unit and radiates the circularly polarized electromagnetic waves to a free space; when one path of electromagnetic waves in the TEM mode is input from an input port of a feed network based on the SISL structure, the feed network based on the SISL structure changes the electromagnetic waves entering the feed network into sixteen paths of electromagnetic waves in the TEM mode, the electromagnetic waves are correspondingly output to sixteen mode separators one by one at sixteen output ports of the feed network, the sixteen paths of electromagnetic waves in the TEM mode are continuously transmitted through the sixteen mode separators, a second output port of the sixteen mode separators continuously transmits the sixteen paths of electromagnetic waves in the TEM mode to second input ports of sixteen radiating units, and each radiating unit changes one path of electromagnetic waves input into the feed network into another path of circularly polarized electromagnetic waves through an inner partition plate structure and a stepped gradient horn structure of each radiating unit and radiates the other path of circularly polarized electromagnetic waves to a free space.

In order to verify the performance of the dual-mode dual-circularly polarized antenna array, HFSS simulation is performed on the dual-mode dual-circularly polarized antenna array. The simulation curve of the reflection coefficient of the dual-mode dual circularly polarized antenna array of the invention is shown in fig. 12, and the simulation curve of the axial ratio of the dual-mode dual circularly polarized antenna array of the invention is shown in fig. 13. The simulation curve diagram of the gain of the dual-mode dual circularly polarized antenna array of the invention is shown in fig. 14.

Analysis of FIG. 12 reveals that: the reflection coefficient S of the input port (port 1) of the feed network based on the hollow waveguide structure is within the whole working frequency band (18-21 GHz) ₁₁ Below-10.8 dB, reflection coefficient S of input port (port 2) of SISL-based feed network ₂₂ Isolation between port 1 and port 2, S, below-11.9 dB ₁₂ Below-15 dBi. Analysis of FIG. 13 reveals that: the axial ratio of the input port (port 1) of the feeding network based on the hollow waveguide structure is below 22.5dB and the axial ratio of the input port (port 2) of the feeding network based on the SISL structure is below 2.7dB in the whole working frequency band (18-21 GHz). Analysis of fig. 14 reveals that the gain of the input port (port 1) of the feeding network based on the hollow core waveguide structure is in the range of 24.8-26.9dBi and the gain of the input port (port 2) of the feeding network based on the SISL structure is in the range of 25-26.9dBi in the whole operating frequency band (18-21 GHz). In summary, the dual-mode dual-circularly polarized antenna array has a low profile, a good axial ratio, a simple structure, and can meet the application requirements of a satellite communication link on high gain and low cost.

Claims

1. A dual-mode dual-circularly polarized antenna array comprises a dual-mode feed network and a radiation network which are stacked from bottom to top, wherein the dual-mode feed network is used for transmitting electromagnetic waves in TE10 modes and TEM modes input at the dual-mode feed network to the radiation network; the radiation network is used for radiating the electromagnetic wave transmitted to the radiation network to free space; the dual-mode feed network is a hybrid feed network based on a hollow waveguide structure and a SISL structure; the radiation network is a mixed radiation network based on a clapboard structure and a step gradient horn structure.

2. The dual-mode dual-circularly polarized antenna array of claim 1, wherein the radiating network comprises three metal plates and 16 radiating elements disposed on the three metal plates; the three metal plates are respectively called a first metal plate, a second metal plate and a third metal plate; the second metal plate is positioned below the first metal plate, the third metal plate is positioned below the second metal plate, the first metal plate, the second metal plate and the third metal plate are square plates and have the same size, the first metal plate, the second metal plate and the third metal plate are vertically aligned and laminated together, the length direction of each metal plate is taken as the left-right direction, the width direction is taken as the front-back direction, and the thickness direction is taken as the vertical direction; each radiation unit comprises a first radiation component, a second radiation component and a third radiation component; the first radiation assembly comprises four cylindrical hollow waveguides arranged on the first metal plate, and the four cylindrical hollow waveguides are respectively called a first cylindrical hollow waveguide, a second cylindrical hollow waveguide, a third cylindrical hollow waveguide and a fourth cylindrical hollow waveguide; the radiuses of the four cylindrical hollow waveguides are equal, the four cylindrical hollow waveguides vertically penetrate through the first metal plate, the first cylindrical hollow waveguides, the second cylindrical hollow waveguides, the third cylindrical hollow waveguides and the fourth cylindrical hollow waveguides are uniformly distributed at intervals in a 2-row 2-column mode, the row direction of the four cylindrical hollow waveguides is along the front-back direction, the column direction of the four cylindrical hollow waveguides is along the left-right direction, the first cylindrical hollow waveguides are located in a 1 st-row 1 st-column, the second cylindrical hollow waveguides are located in a 2 nd-row 1 st-column, the third cylindrical hollow waveguides are located in a 1 st-row 2 nd-column, the fourth cylindrical hollow waveguides are located in a 2 nd-row 2 nd-column, the central distance between the first cylindrical hollow waveguides and the second cylindrical hollow waveguides is 12.5mm, and the central distance between the first cylindrical hollow waveguides and the third cylindrical hollow waveguides is 12.5mm, the center distance between the fourth cylindrical hollow waveguide and the second cylindrical hollow waveguide is 12.5mm, the center distance between the third cylindrical hollow waveguide and the fourth cylindrical hollow waveguide is 12.5mm, the first cylindrical hollow waveguide and the second cylindrical hollow waveguide are symmetrical front and back, the plane where the front and back symmetry planes are located is called a first symmetry plane, the first cylindrical hollow waveguide and the third cylindrical hollow waveguide are symmetrical left and right, the plane where the left and right symmetry planes are located is called a second symmetry plane, the intersection of the first symmetry plane and the second symmetry plane is the center line of the first radiation component, the plane where the symmetry plane of the first cylindrical hollow waveguide along the front and back direction is located is called a third symmetry plane, the plane where the symmetry plane of the first cylindrical hollow waveguide along the left and right direction is located is called a fourth symmetry plane, the straight line where the center line of the first radiation assembly is located is called the center of the radiation unit; the second radiation assembly comprises a three-stage step gradient horn arranged on the second metal plate, the three-stage step gradient horn is composed of three square hollow waveguides, and the three square hollow waveguides are respectively called a first square hollow waveguide, a second square hollow waveguide and a third square hollow waveguide; the first square hollow waveguide, the second square hollow waveguide and the third square hollow waveguide are distributed from top to bottom in sequence, the upper end surfaces of the first square hollow waveguide, the second square hollow waveguide and the third square hollow waveguide are square, the upper end surface of the first square hollow waveguide is flush with the upper end surface of the second metal plate, and the central line of the first square hollow waveguide in the vertical direction and the central line of the first radiation assembly are positioned on the same straight line; four edges of the first square hollow waveguide along the vertical direction are chamfered, the plane of the front end surface of the first square hollow waveguide is positioned on the front side of the fourth symmetrical surface, the distance between the plane and the plane is greater than the radius of the first hollow waveguide, the upper end surface of the second square hollow waveguide is connected with the lower end surface of the first square hollow waveguide in a joint state, the central line of the second square hollow waveguide along the vertical direction and the central line of the first square hollow waveguide along the vertical direction are positioned on the same straight line, the side length of the second square hollow waveguide is smaller than that of the first square hollow waveguide, the height of the second square hollow waveguide along the vertical direction is smaller than that of the first square hollow waveguide along the vertical direction, the plane where the front end surface of the second square hollow waveguide is located on the front side of the fourth symmetrical surface, and the distance between the plane and the fourth symmetrical surface is smaller than the radius of the first cylindrical hollow waveguide, the upper end surface of the third square hollow waveguide is connected with the lower end surface of the second square hollow waveguide in a joint state, the central line of the third square hollow waveguide along the vertical direction and the central line of the second square hollow waveguide along the vertical direction are positioned on the same straight line, the lower end surface of the third square hollow waveguide is flush with the lower end surface of the second metal plate, the side length of the third square hollow waveguide is smaller than that of the second square hollow waveguide, the height of the third square hollow waveguide along the vertical direction is greater than that of the second square hollow waveguide along the vertical direction, the plane where the front end face of the third square hollow waveguide is located on the rear side of the fourth symmetrical plane, and the distance between the plane and the fourth square hollow waveguide is smaller than the radius of the first cylindrical hollow waveguide; the third radiation assembly comprises a first square groove and a five-stage metal ladder which are arranged on the third metal plate; the first square groove vertically penetrates through the third metal plate, the central line of the first square groove along the vertical direction and the central line of the third square hollow waveguide along the vertical direction are positioned on the same straight line, the front end surface of the first square groove and the front end surface of the third square hollow waveguide are positioned on the same plane, the rear end surface of the first square groove and the rear end surface of the third square hollow waveguide are positioned on the same plane, the left end surface of the first square groove and the left end surface of the third square hollow waveguide are positioned on the same plane, the right end surface of the first square groove and the right end surface of the third square hollow waveguide are positioned on the same plane, the five-stage metal ladder comprises five rectangular metal blocks which are respectively called as a first rectangular metal block, a second rectangular metal block, a third rectangular metal block, a fourth rectangular metal block and a fifth rectangular metal block, the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are sequentially arranged in the first rectangular groove according to the sequence from the front to the back, the front end face of the first rectangular metal block is fixedly connected with the front end face of the first rectangular groove and is in a joint state, the front end face of the second rectangular metal block is fixedly connected with the back end face of the first rectangular metal block and is in a joint state, the front end face of the third rectangular metal block is fixedly connected with the back end face of the second rectangular metal block and is in a joint state, the front end face of the fourth rectangular metal block is fixedly connected with the back end face of the third rectangular metal block and is in a joint state, the front end face of the fifth rectangular metal block is fixedly connected with the back end face of the fourth rectangular metal block and is in a joint state, the rear end face of the fifth rectangular metal block is fixedly connected with the rear end face of the first square groove and is in a joint state, the left end faces of the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are positioned on the same plane, the right end faces of the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are positioned on the same plane, the lower end faces of the first rectangular metal block, the second rectangular metal block, the third rectangular metal block, the fourth rectangular metal block and the fifth rectangular metal block are positioned on the same plane with the lower end face of the first square groove, the distance from the right end surface of the first rectangular metal block to the right end surface of the first rectangular groove is equal to the distance from the left end surface of the first rectangular metal block to the left end surface of the first rectangular groove, the length of the first rectangular metal block in the left-right direction is smaller than the length of the first rectangular groove in the left-right direction, the upper end surface of the first rectangular metal block and the upper end surface of the first rectangular groove are positioned on the same plane, the width of the second rectangular metal block in the front-back direction is smaller than the width of the first rectangular metal block in the front-back direction, the height of the second rectangular metal block in the up-down direction is smaller than the height of the first rectangular metal block in the up-down direction, the width of the third rectangular metal block in the front-back direction is larger than the width of the second rectangular metal block in the front-back direction, and the height of the third rectangular metal block in the up-down direction is smaller than the height of the second rectangular metal block in the up-down direction, the width of the fourth rectangular metal block along the front-back direction is larger than that of the third rectangular metal block along the front-back direction, and the height of the fourth rectangular metal block along the up-down direction is smaller than that of the third rectangular metal block along the up-down direction; the width of the fifth rectangular metal block along the front-back direction is smaller than the width of the fourth rectangular metal block along the front-back direction, and the height of the fifth rectangular metal block along the up-down direction is smaller than the height of the fourth rectangular metal block along the up-down direction; a first input port of the radiation unit is defined by the front end of the lower end surface of the first square groove, the rear end of the lower end surface of the first square groove, the left end of the lower end surface of the first square groove and the left end of the lower end surface of the five-level metal ladder, a second input port of the radiation unit is defined by the front end of the lower end surface of the first square groove, the rear end of the lower end surface of the first square groove, the right end of the lower end surface of the first square groove and the right end of the lower end surface of the five-level metal ladder, and the upper end surfaces of the four cylindrical hollow waveguides jointly form an output port of the radiation unit; the 16 radiation units are uniformly distributed at intervals in a 4-row and 4-column mode, the row direction of the radiation units is along the front-back direction, the column direction of the radiation units is along the left-right direction, the distance between the center lines of every two adjacent radiation units in the same row is 25mm, and the distance between the center lines of every two adjacent radiation units in the same column is 25mm.

3. The dual-mode dual-circularly-polarized antenna array according to claim 2, wherein the dual-mode feed network comprises two metal plates, a dielectric plate, a hollow waveguide-based power divider and sixteen mode splitters, the two metal plates are called a fourth metal plate and a fifth metal plate, the fourth metal plate, the dielectric plate and the fifth metal plate are stacked in sequence from top to bottom, the lengths of the fourth metal plate, the dielectric plate and the fifth metal plate in the left-right direction are equal, the lengths of the fourth metal plate, the dielectric plate and the fifth metal plate in the front-back direction are equal, the fourth metal plate is located below the third metal plate, the upper end face of the fourth metal plate is attached to the lower end face of the third metal plate, the left end face of the fourth metal plate is flush with the left end face of the third metal plate, the right end face of the fourth metal plate is flush with the right end face of the third metal plate, the front end face of the fourth metal plate is flush with the front end face of the third metal plate, and the rear end face of the fourth metal plate is flush with the rear end face of the third metal plate; a first copper-clad layer is attached to the upper surface of the dielectric plate, the front end surface of the first copper-clad layer is flush with the front end surface of the dielectric plate, the rear end surface of the first copper-clad layer is flush with the rear end surface of the dielectric plate, the left end surface of the first copper-clad layer is flush with the left end surface of the dielectric plate, the right end surface of the first copper-clad layer is flush with the right end surface of the dielectric plate, a second copper-clad layer is attached to the lower surface of the dielectric plate, the front end surface of the second copper-clad layer is flush with the front end surface of the dielectric plate, the rear end surface of the second copper-clad layer is flush with the rear end surface of the dielectric plate, the left end surface of the second copper-clad layer is flush with the left end surface of the dielectric plate, and the right end surface of the second copper-clad layer is flush with the right end surface of the dielectric plate; the hollow waveguide-based sixteen-power divider has an input port and sixteen output ports, the thickness direction of the hollow waveguide-based sixteen-power divider is along the up-down direction, the hollow waveguide-based sixteen-power divider is divided into an upper half structure and a lower half structure along the thickness direction of the hollow waveguide-based sixteen-power divider, the upper half structure of the hollow waveguide-based sixteen-power divider is disposed on the fourth metal plate, the upper half structure of the hollow waveguide-based sixteen-power divider is referred to as a first feeding portion, the lower half structure of the hollow waveguide-based sixteen-power divider is disposed on the fifth metal plate, the lower half structure of the hollow waveguide-based sixteen-power divider is referred to as a second feeding portion, the first feeding portion and the second feeding portion are completely aligned up and down, and if the second feeding portion moves downward, the lower feeding portion and the second feeding portion are spliced to form a complete hollow waveguide-based sixteen-power divider structure; the first copper-clad layer is provided with a first groove with the same contour as a sixteen-one power divider based on a hollow waveguide, the second copper-clad layer is provided with a second groove with the same contour as a sixteen-one power divider based on the hollow waveguide, if the first groove moves downwards, the first copper-clad layer and the second copper-clad layer are completely overlapped, the first feeding part moves downwards to enter the first groove and completely falls inside the first groove, if the second feeding part moves upwards to enter the second groove and completely falls inside the second groove, the first metalized through holes sequentially penetrate through the first copper-clad layer, the dielectric plate and the second copper-clad layer from top to bottom, the first metalized through holes surround a sixteen-one power divider contour area, and if the first feeding part moves downwards, the first metalized through holes completely enter the sixteen power divider contour area; the outline area of the sixteen-branch power divider surrounded by the first metalized through holes is called a first area, the input port of the first area, which corresponds to the sixteen-branch power divider, is taken as the input port of the first area, the sixteen output ports of the first area, which corresponds to the sixteen-branch power divider, are taken as the sixteen output ports of the first area, and the first area is provided with one input port and sixteen output ports; the first feeding part and the second feeding part form a feeding network based on a hollow waveguide structure, the first feeding part is provided with the upper half parts of the input port and the sixteen output ports of the one-sixteen power divider based on the hollow waveguide, and the upper half parts of the input port and the sixteen output ports of the one-sixteen power divider based on the hollow waveguide are used as one input port and sixteen output ports of the first feeding part; the second feeding part is provided with the lower half parts of the input port and the sixteen output ports of the hollow waveguide-based one-sixteen power divider, and the lower half parts of the input port and the sixteen output ports of the hollow waveguide-based one-sixteen power divider are used as one input port and sixteen output ports of the second feeding part; an input port of the first feeding portion and an input port of the second feeding portion together form an input port of the hollow waveguide structure-based feeding network; sixteen output ports of the first feeding part and sixteen output ports of the second feeding part are in one-to-one correspondence up and down to jointly form sixteen output ports of the feeding network based on the hollow waveguide structure; the feed network based on the hollow waveguide structure is provided with an input port and sixteen output ports, and is used for converting one path of electromagnetic waves in a TE10 mode, which are connected to the input port, into sixteen paths of electromagnetic waves in a TE10 mode, and outputting the electromagnetic waves at sixteen output ends in a one-to-one correspondence manner; the first feeding portion, the dielectric plate, the first copper-clad layer, the second copper-clad layer and the second feeding portion form a SISL structure-based feeding network, and an input port of the first feeding portion, an input port of the second feeding portion and an input port of the first region together form an input port of the SISL structure-based feeding network; sixteen output ports of the first feeding portion, sixteen output ports of the second feeding portion and sixteen output ports of the first region are in one-to-one butt joint from top to bottom to form sixteen output ports of a SISL structure-based feeding network; the feed network based on the SISL structure is provided with an input port and sixteen output ports, and is used for changing one path of electromagnetic waves in a TEM mode form accessed by the input port into sixteen paths of electromagnetic waves in a TEM mode form and outputting the electromagnetic waves at the sixteen output ports in a one-to-one correspondence manner; the structure and the size of sixteen mode separators are completely the same, and each mode separator comprises a hollow waveguide part, an anti-leakage structure, a copper-clad block and five metal columns; the hollow waveguide part comprises seven rectangular hollow waveguides which are respectively called a first rectangular hollow waveguide, a second rectangular hollow waveguide, a third rectangular hollow waveguide, a fourth rectangular hollow waveguide, a fifth rectangular hollow waveguide, a sixth rectangular hollow waveguide and a seventh rectangular hollow waveguide; the first rectangular hollow waveguide, the second rectangular hollow waveguide, the third rectangular hollow waveguide, the fourth rectangular hollow waveguide and the fifth rectangular hollow waveguide are all arranged on the fourth metal plate, and the upper end surface of the first rectangular hollow waveguide is flush with the upper end surface of the fourth metal plate; the front end face of the first rectangular hollow waveguide, the front end face of the second rectangular hollow waveguide, the front end face of the third rectangular hollow waveguide, the front end face of the fourth rectangular hollow waveguide, the front end face of the fifth rectangular hollow waveguide, the front end face of the sixth rectangular hollow waveguide and the front end face of the seventh rectangular hollow waveguide are flush; the rear end face of the first rectangular hollow waveguide, the rear end face of the second rectangular hollow waveguide, the rear end face of the third rectangular hollow waveguide, the rear end face of the fourth rectangular hollow waveguide, the rear end face of the fifth rectangular hollow waveguide, the rear end face of the sixth rectangular hollow waveguide and the rear end face of the seventh rectangular hollow waveguide are flush; the upper end surface of the first rectangular hollow waveguide is flush with the upper end surface of the fourth metal plate, the second rectangular hollow waveguide is positioned below the first rectangular hollow waveguide, the lower end surface of the first rectangular hollow waveguide is connected with the upper end surface of the second rectangular hollow waveguide in a fitting state, and the lower end surface of the second rectangular hollow waveguide is positioned above the lower end surface of the fourth metal plate; the left end face of the second rectangular hollow waveguide is positioned on the left side of the plane where the left end face of the first rectangular hollow waveguide is positioned; the right end face of the second rectangular hollow waveguide is positioned on the left side of the plane where the right end face of the first rectangular hollow waveguide is positioned; the thickness of the second rectangular hollow waveguide along the vertical direction is smaller than that of the first rectangular hollow waveguide along the vertical direction; the third rectangular hollow waveguide is positioned below the second rectangular metal waveguide, and the upper end surface of the third rectangular hollow waveguide is connected with the lower end surface of the second rectangular metal waveguide and is in a joint state; the lower end surface of the third rectangular hollow waveguide is flush with the lower end surface of the fourth metal plate; the left end surface of the third rectangular hollow waveguide is flush with the left end surface of the second rectangular hollow waveguide; the right end face of the third rectangular hollow waveguide is positioned on the right side of the plane where the right end face of the first rectangular hollow waveguide is positioned; the thickness of the third rectangular hollow waveguide along the vertical direction is smaller than that of the second rectangular hollow waveguide along the vertical direction; the fourth rectangular hollow waveguide and the first rectangular hollow waveguide are bilaterally symmetrical relative to the plane of the symmetry plane of the third rectangular hollow waveguide in the front-back direction, and the fifth rectangular hollow waveguide and the second rectangular hollow waveguide are bilaterally symmetrical relative to the plane of the symmetry plane of the third rectangular hollow waveguide in the front-back direction; the sixth rectangular hollow waveguide and the seventh rectangular hollow waveguide are both arranged on the fifth metal plate, and the upper end surface of the sixth rectangular hollow waveguide is flush with the upper end surface of the fifth metal plate; the left end surface of the sixth rectangular hollow waveguide is flush with the left end surface of the third rectangular hollow waveguide; the right end face of the sixth rectangular hollow waveguide is flush with the right end face of the third rectangular hollow waveguide; the length of the sixth rectangular hollow waveguide along the left-right direction is consistent with that of the third rectangular hollow waveguide along the left-right direction; the thickness of the sixth rectangular hollow waveguide along the vertical direction is consistent with that of the third rectangular hollow waveguide along the vertical direction; the seventh rectangular hollow waveguide is positioned below the sixth rectangular hollow waveguide, and the upper end surface of the seventh rectangular hollow waveguide is connected with the lower end surface of the sixth rectangular hollow waveguide in a joint state; the lower end surface of the seventh rectangular hollow waveguide is positioned above the lower end surface of the fifth metal plate; the left end face of the seventh rectangular hollow waveguide is positioned on the right side of the plane where the left end face of the sixth rectangular hollow waveguide is positioned; the right end face of the seventh rectangular hollow waveguide is flush with the right end face of the sixth rectangular hollow waveguide; the leakage-proof structure comprises a plurality of second metalized through holes penetrating through the first copper-clad layer, the dielectric plate and the second copper-clad layer from top to bottom, the second metalized through holes surround a rectangular area, and if the third rectangular air waveguide moves downwards, the third rectangular air waveguide can enter the rectangular area; the copper-clad block comprises three rectangular copper sheets which are respectively called a first rectangular copper sheet, a second rectangular copper sheet and a third rectangular copper sheet, an opening is formed in the first copper-clad layer, the first rectangular copper sheet, the second rectangular copper sheet and the third rectangular copper sheet are positioned at the opening, the upper end faces of the first rectangular copper sheet, the second rectangular copper sheet and the third rectangular copper sheet are flush, and the lower end faces of the first rectangular copper sheet, the second rectangular copper sheet and the third rectangular copper sheet are connected with the upper end face of the dielectric plate and are in a fit state; the rear end face of the first rectangular copper sheet is flush with the rear end face of the third rectangular hollow waveguide, the front end face of the first rectangular copper sheet is positioned behind the plane where the front end face of the third rectangular hollow waveguide is positioned and on the front side of the plane where the rear end face of the third rectangular hollow waveguide is positioned, and the distance from the left end face of the first rectangular copper sheet to the plane where the left end face of the third rectangular hollow waveguide is positioned is equal to the distance from the right end face of the first rectangular copper sheet to the plane where the right end face of the third rectangular hollow waveguide is positioned; the second rectangular copper sheet is positioned on the front side of the first rectangular copper sheet, the rear end face of the second rectangular copper sheet is connected with the front end face of the first rectangular copper sheet and is in a fit state, the left end face of the second rectangular copper sheet is positioned on the left side of the plane where the left end face of the first rectangular copper sheet is positioned, the right end face of the second rectangular copper sheet is positioned on the right side of the plane where the right end face of the first rectangular copper sheet is positioned, and the distance from the plane where the left end face of the second rectangular copper sheet is positioned to the left end face of the first rectangular copper sheet is equal to the distance from the plane where the right end face of the second rectangular copper sheet is positioned to the right end face of the first rectangular copper sheet; the length of the second rectangular copper sheet along the left-right direction is larger than that of the first rectangular copper sheet along the left-right direction, the width of the second rectangular copper sheet along the front-back direction is larger than that of the first rectangular copper sheet along the front-back direction, the third rectangular copper sheet is positioned on the right side of the second rectangular copper sheet, the front end face of the third rectangular copper sheet is flush with the front end face of the second rectangular copper sheet, the left end face of the third rectangular copper sheet is connected with the right end face of the second rectangular copper sheet and is in a bonding state, and the width of the third rectangular copper sheet along the front-back direction is smaller than that of the second rectangular copper sheet along the front-back direction; five metal columns penetrate through the first copper-clad layer, the dielectric plate and the second copper-clad layer, the upper parts of the five metal columns are positioned in the third rectangular hollow waveguide, the lower parts of the five metal columns are positioned in the sixth rectangular hollow waveguide, and the upper end surfaces of the five metal columns are flush with the upper end surface of the third rectangular hollow waveguide; the lower end faces of the five metal columns are flush with the lower end face of the sixth rectangular hollow waveguide; the five metal columns are cylindrical and are respectively called a first metal column, a second metal column, a third metal column, a fourth metal column and a fifth metal column; the first metal posts, the second metal posts and the third metal posts are arranged at intervals in a row from back to front, the distance between the first metal posts and the second metal posts is not equal to the distance between the second metal posts and the third metal posts, the distance between the axis of the first metal posts and the plane where the rear end face of the third rectangular hollow waveguide is located is larger than the radius of the first metal posts, the distance between the axis of the first metal posts and the plane where the right end face of the third rectangular hollow waveguide is located is larger than the radius of the first metal posts, the distance between the axis of the third metal posts and the plane where the front end face of the third rectangular hollow waveguide is located is larger than the radius of the third metal posts, and the distance between the axis of the third metal posts and the plane where the right end face of the third rectangular hollow waveguide is located is larger than the radius of the third metal posts, the first metal column and the second metal column are positioned on the right side of the plane where the right end face of the second rectangular copper sheet is positioned and on the rear side of the plane where the rear end face of the third rectangular copper sheet is positioned, the third metal column is positioned on the front side of the plane where the front end face of the third rectangular copper sheet is positioned, the fourth metal column is positioned on the left side of the plane where the left end face of the second rectangular copper sheet is positioned, the distance between the axis of the fourth metal column and the plane where the left end face of the third rectangular hollow waveguide is positioned is greater than the radius of the fourth metal column, the distance between the axis of the fourth metal column and the plane where the front end face of the third rectangular hollow waveguide is positioned is greater than the radius of the fourth metal column, and the fifth metal column is positioned on the right front side of the fourth metal column and on the left front side of the third metal column The distance from the fifth metal column to the plane where the front end face of the third rectangular hollow waveguide is located is larger than the radius of the fifth metal column; each mode separator is provided with an input port and two output ports, and the two output ports are respectively called a first output port and a second output port; the rear end face of the third rectangular air waveguide and the rear end face of the sixth rectangular air waveguide jointly form an input port of the mode splitter, the upper end face of the first rectangular hollow waveguide serves as a first output port of the mode splitter, and the upper end face of the fifth rectangular hollow waveguide serves as a second output port of the mode splitter; the sixteen mode separators are uniformly distributed at intervals in a 4-row and 4-column mode, the row direction of the sixteen mode separators is along the front-back direction, the column direction of the sixteen mode separators is along the left-right direction, the center distance between the first rectangular hollow waveguides of every two adjacent mode separators in the same row is 25mm, and the center distance between the first rectangular hollow waveguides of every two adjacent mode separators in the same column is 25mm; the input ports of the sixteen mode splitters are connected with sixteen output ports of the feeding network based on the hollow waveguide structure or the feeding network based on the SISL structure in a one-to-one correspondence manner, the first output ports of the sixteen mode splitters are connected with the first input ports of the sixteen radiating units in a one-to-one correspondence manner, and the second output ports 2 of the sixteen mode splitters are connected with the second input ports of the sixteen radiating units in a one-to-one correspondence manner.

4. A dual-mode dual-circular polarized antenna array according to claim 3, wherein the radius of each of the four cylindrical hollow waveguides is 5.1mm, the side length of the second square hollow waveguide is 7mm smaller than the side length of the first square hollow waveguide, the vertical height of the second square hollow waveguide is 2.8mm smaller than the vertical height of the first square hollow waveguide, the side length of the third square hollow waveguide is 7.3mm smaller than the side length of the second square hollow waveguide, the vertical height of the third square hollow waveguide is 0.2mm greater than the vertical height of the second square hollow waveguide, the vertical four edges of the first square hollow waveguide are chamfered, the radius of the chamfer is 3mm, the vertical width of the second rectangular metal block is 0.56mm smaller than the vertical width of the first rectangular metal block, the vertical height of the second rectangular metal block is 3.56 mm greater than the vertical width of the first rectangular metal block, the vertical height of the second rectangular metal block is 5.85mm greater than the vertical height of the third metal block, the vertical height of the third metal block is 3.8mm greater than the vertical height of the fourth metal block; the width of the fifth rectangular metal block along the front-back direction is 4.35mm smaller than that of the fourth rectangular metal block along the front-back direction, and the height of the fifth rectangular metal block along the up-down direction is 1.95mm smaller than that of the fourth rectangular metal block along the up-down direction; the distance between the lower end surface of the second rectangular hollow waveguide and the lower end surface of the fourth metal plate is 1.3mm; the distance between the left end surface of the second rectangular hollow waveguide and the plane where the left end surface of the first rectangular hollow waveguide is located is 0.2mm; the distance between the right end face of the second rectangular hollow waveguide and the plane where the right end face of the first rectangular hollow waveguide is located is 1.6mm; the thickness of the second rectangular hollow waveguide along the vertical direction is 1.05mm smaller than that of the first rectangular hollow waveguide along the vertical direction; the distance between the right end face of the third rectangular hollow waveguide and the plane where the right end face of the first rectangular hollow waveguide is located is 11mm; the thickness of the third rectangular hollow waveguide along the vertical direction is 0.15mm smaller than that of the second rectangular hollow waveguide along the vertical direction; the distance between the lower end face of the seventh rectangular hollow waveguide and the lower end face of the fifth metal plate is 2.9mm; the distance between the left end surface of the seventh rectangular hollow waveguide and the plane where the left end surface of the sixth rectangular hollow waveguide is located is 11.5mm, the distance between the front end surface of the first rectangular copper sheet and the plane where the front end surface of the third rectangular hollow waveguide is located is 7.05mm, the length of the second rectangular copper sheet in the left-right direction is 0.59mm larger than that of the first rectangular copper sheet in the left-right direction, the width of the second rectangular copper sheet in the front-back direction is 0.3mm larger than that of the first rectangular copper sheet in the front-back direction, and the width of the third rectangular copper sheet in the front-back direction is 1.43mm smaller than that of the second rectangular copper sheet in the front-back direction; the edges of the second rectangular copper sheet in the left front direction are rounded with the radius of 2.6 mm; the radii of the five metal columns are all 0.3mm.