A light and thin waveguide slot antenna

Abstract

The application discloses a light and thin waveguide slot antenna, which comprises a waveguide cavity and a feeding printed board, and the feeding printed board is located below the waveguide cavity; a waveguide wall is arranged in the waveguide cavity, and the waveguide wall divides the waveguide cavity of the whole waveguide cavity into a first waveguide cavity and a second waveguide cavity; the first waveguide cavity is a rectangular waveguide cavity, and the second waveguide cavity is a ridge waveguide cavity. The waveguide slot antenna only adopts one layer of waveguide cavity, and the feeding network integrates an electric bridge, a power division network and a coupling feeding strip line, so that the waveguide slot antenna has the advantages of light weight, light weight, simple antenna processing and assembly.

Description

Technical Field

[0001] The present invention relates to the technical field of microwave antennas, and in particular to a lightweight and thin waveguide slot antenna. Background Art

[0002] Circularly polarized antennas can eliminate polarization distortion caused by the Faraday rotation effect of the ionosphere, resist interference from rain and fog on electromagnetic signals, and reduce performance losses caused by polarization mismatch. Therefore, circularly polarized antennas are widely used in wireless communications, radar, and other fields. In circularly polarized phased array radars, left-hand or right-hand circular polarization is used for transmission. However, the electromagnetic signal changes its direction after a single reflection, necessitating the use of the opposite right-hand or left-hand circular polarization for reception. Therefore, radiating antenna elements with dual circular polarization can be used to minimize the impact of polarization mismatch on radar range. Common methods for implementing dual circularly polarized antennas include cross-element antennas with a circularly polarized bridge, patch antennas with a 90° bridge, and waveguide antennas with a baffle polarizer. These designs, when applied to antenna arrays, typically require complex feed networks, reducing antenna efficiency and increasing manufacturing costs.

[0003] As a high-efficiency and easy-to-array antenna, waveguide slot antennas are widely used in communication, radar and other systems. Waveguide slot antennas mainly use two slot forms: wide-side slots and narrow-side slots. The polarization form is usually linear polarization or dual-linear polarization. The literature "Wang Wei, Broadband Diaphragm-Excited Waveguide Narrow-Side Non-Tilted Slot Array Antenna, Journal of Microwaves, 2005, 21(5)" theoretical analysis points out that when the number of slots is large, the bandwidth of the waveguide slot antenna will be limited. In this paper, a single waveguide has 16 slots, which are divided into 4 resonant arrays. The antenna bandwidth is increased from 2% to 8%. However, a waveguide power divider needs to be added below the waveguide for feeding, which undoubtedly increases the cross-sectional height, weight and processing difficulty of the antenna. The patent "Lu Jiaguo, Dual-polarized slot waveguide antenna array, CN104518289A" discloses a design in which the wide-side slots are staggered along the wide-side centerline and the narrow-side slots are inclined slots. The waveguide cavity is divided into a radiation waveguide and a feeding waveguide. The antenna has a high cross-section, and the structure and processing of the antenna multi-layer cavity are complex, requiring high processing accuracy. The patent "Song Guodong, A broadband dual-polarized waveguide slot antenna, CN113285215A" discloses a design in which the wide-side slots are arranged along the wide-side centerline and vertical slots are arranged on the narrow side. The slots are staggered with disturbance blocks to achieve dual-polarized radiation. The waveguide antenna is fed by a coaxial connector, and the feed matching block is located inside the waveguide cavity, which also has the disadvantage of being difficult to process. The paper "Zhang Zhihui, High-efficiency Dual Circularly Polarized Antenna Array, Design and Development, 2019,6." and the invention "Zhang Hongtao, A Circularly Polarized Waveguide Slot Antenna and Its Design Method, CN104538742A" respectively proposed to use the combination of long slots and oblique slots of ridge waveguide antennas to achieve the circularly polarized radiation performance of waveguide slot antennas, but only single circularly polarized radiation performance can be formed. Summary of the Invention

[0004] To solve the above problems, the present invention proposes a lightweight waveguide slot antenna, comprising a waveguide cavity and a feed printed circuit board, wherein the feed printed circuit board is located below the waveguide cavity; a waveguide wall is provided in the waveguide cavity, which divides the entire waveguide cavity into a first waveguide cavity and a second waveguide cavity, wherein the first waveguide cavity is a rectangular waveguide cavity and the second waveguide cavity is a ridge waveguide cavity;

[0005] The waveguide cavity is assembled from two parts: the upper cavity part and the lower cavity part. The waveguide wall divides the lower cavity part into a first cavity lower part and a second cavity lower part. An "L"-shaped first feeding slot is opened on the left and right parts of the bottom of the first cavity lower part; an "H"-shaped second feeding slot is opened on the left and right parts of the bottom of the second cavity lower part.

[0006] The upper metal surface of the feeding printed board is etched with a third feeding slot in the shape of "L" and a fourth feeding slot in the shape of "H"; the position, size and shape of the third feeding slot correspond to those of the first feeding slot, and the position, size and shape of the fourth feeding slot correspond to those of the second feeding slot, forming a signal transmission channel.

[0007] Further, the rear part of the upper part of the cavity is higher than the front part by one step, 2n narrow-edge slots perpendicular to the azimuth direction are formed on the rear part of the upper part of the cavity, and the narrow-edge slots are uniformly distributed on the rear part of the upper part of the cavity; 2n wide-edge slots parallel to the azimuth direction are formed on the front part of the upper part of the cavity.

[0008] Further, narrow-edge slot disturbance blocks are staggered and arranged on the upper and lower sides of the narrow-edge slots, and the narrow-edge slot disturbance blocks are on both sides of the narrow-edge slots; wide-edge slot disturbance blocks are staggered and arranged on both sides of the wide-edge slots; the narrow-edge slot disturbance blocks and the wide-edge slot disturbance blocks are on the inner top surface of the upper part of the cavity.

[0009] Further, the spacing between the wide-edge slots is consistent with the spacing of the narrow-edge slots, and the center line of each wide-edge slot and the center line of the corresponding narrow-edge slot are the same line.

[0010] Further, the lower part of the cavity is a cuboid cavity structure without a top surface, the waveguide wall is located in the middle of the lower part of the cavity, the waveguide wall is located on the interface between the front part and the rear part of the upper part of the cavity, and the waveguide wall is parallel to the azimuth direction and perpendicular to the bottom surface of the lower part of the cavity.

[0011] Further, the middle part of the lower part of the cavity is provided with a partition plate perpendicular to the azimuth direction and perpendicular to the bottom surface of the lower part of the cavity, and the partition plate divides the first waveguide cavity and the second waveguide cavity into left and right parts respectively; the partition plate intersects the waveguide wall perpendicularly; the partition plate divides the first waveguide cavity into two cavities along the azimuth direction, and divides the second waveguide cavity into two cavities along the azimuth direction.

[0012] Further, the second lower part of the cavity is provided with a ridge, the ridge of the second lower part of the cavity is parallel to the waveguide wall, and the ridge divides the second waveguide cavity into left front, left rear, right front and right rear parts with the partition plate; the wide-edge slot is located directly above the ridge.

[0013] Further, the short sides of the two first feeding slots are perpendicular to the azimuth direction and are located at the middle of the first lower part of the cavity and the middle of the first lower part of the cavity respectively. The The long sides of the two first feeding slots are parallel to the azimuth direction, and the "L" shapes of the two first feeding slots are reversed, both facing away from the direction of the partition plate. The The long sides of the two first feeding slots are parallel to the azimuth direction, and the "L" shapes of the two first feeding slots are reversed, both facing away from the direction of the partition plate.

[0014] The two second feeding slots are located at the bottom of the lower part of the second cavity. and The middle of the wide side gap, the bottom of the lower part of the first cavity and The middle of each wide side slot is located in the middle of each wide side slot, and the short horizontal line in the middle of each H-shaped second feeding slot is perpendicular to the ridge and symmetrical about the ridge;

[0015] The second feeding slot penetrates the ridge of the second waveguide cavity from bottom to top, forming a feeding opening of the ridge of the second waveguide cavity to realize the transmission of electromagnetic wave signals.

[0016] Furthermore, the n narrow-side slots distributed on the left cavity of the first waveguide cavity form a group of subarrays, the position of the first narrow-side slot perturbation block is left front and right rear, the position of the second narrow-side slot perturbation block is left rear and right front, and so on; the n narrow-side slots distributed on the right cavity of the first waveguide cavity form another group of subarrays, the positions of the narrow-side slot perturbation blocks are opposite to those of the narrow-side slot perturbation blocks on the left cavity;

[0017] The n broadside slots distributed in the left cavity of the second waveguide cavity form a group of subarrays, and the n broadside slots in the right cavity form another group of subarrays; among the n broadside slots in the left cavity of the second waveguide cavity, the first broadside slot perturbation block is located behind the first broadside slot, the second broadside slot perturbation block is located in front of the second broadside slot, and so on; the positions of the n broadside slot perturbation blocks in the right cavity of the second waveguide cavity are opposite to those of the broadside slot perturbation blocks in the left cavity.

[0018] Furthermore, the feed printed board is a microwave stripline structure, and further includes a stripline, a microwave dielectric board, a lower metal surface, a left-hand circular polarization port connector, and a right-hand circular polarization port connector; the stripline includes a bridge, a "T"-shaped power splitter, an "L"-shaped slot coupling and matching section, a phase compensation section, and an "H"-shaped slot coupling and matching section;

[0019] The left-hand circular polarization port connector and the right-hand circular polarization port connector are arranged on the lower metal surface of the feed printed board.

[0020] Furthermore, the "L"-shaped slot coupling matching section is located directly below the third feeding slot; the "H"-shaped slot coupling matching section is located directly below the fourth feeding slot; both the "L"-shaped slot coupling matching section and the "H"-shaped slot coupling matching section play the role of excitation slot and impedance matching; the feeding strip line phase compensation section is used to adjust the phase difference between the first waveguide cavity and the second waveguide cavity.

[0021] Further, the upper metal surface and the lower metal surface are interconnected through metal shielding holes, and the metal shielding holes are uniformly distributed on both sides of the strip line; the feeding printed board further comprises mounting screws, the feeding printed board is provided with a plurality of mounting holes, and the mounting screws pass through the mounting holes to mount the feeding printed board with the waveguide cavity; when the feeding printed board is mounted, the upper metal surface of the feeding printed board is attached to the bottom of the waveguide cavity.

[0022] Compared with the prior art, the present application has the following beneficial effects:

[0023] 1. The waveguide cavity structure is simple: the waveguide cavity in the present application adopts a single-layer rectangular waveguide cavity and a ridge waveguide cavity, the rectangular waveguide cavity and the ridge waveguide cavity are co-wall designed, and are divided into two parts when processed, only one welding is needed, and the processing difficulty is reduced.

[0024] 2. Low profile and light weight: the antenna in the present application adopts the form of one layer of cavity plus a feeding printed board, the profile is lower than that of the traditional waveguide slot antenna, the feeding waveguide is omitted, the processing difficulty of the antenna is simplified, and the profile height and weight of the antenna are reduced.

[0025] 3. New feeding form: the antenna in the present application adopts the feeding forms of L-shaped coupling feeding slot, H-shaped coupling feeding slot and coupling feeding strip line, and realizes the wideband working performance of the antenna. Compared with the coaxial probe feeding form of the traditional waveguide slot antenna, the matching block for inserting the coaxial connector does not need to be processed in the waveguide cavity, and the loss introduced by the coaxial feeding is reduced.

[0026] 4. Integration of antenna and feeding network: the antenna in the present application has high integration, integrates the dual circularly polarized electric bridge and the power dividing network in the feeding printed board, and can realize dual circularly polarized working and multiple waveguide slot subarray integrated design. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is an overall appearance view of the antenna of the embodiment of the present application.

[0028] Figure 2 It is a side view of the antenna of the embodiment of the present application.

[0029] Figure 3 It is a top perspective view of the waveguide cavity of the antenna of the embodiment of the present application.

[0030] Figure 4 It is an exploded view of the parts of the antenna of the embodiment of the present application.

[0031] Figure 5 It is a schematic view of L-shaped and H-shaped slotting at the bottom of the waveguide cavity of the antenna of the embodiment of the present application.

[0032] Figure 6The upper layer pattern of the antenna feeding printed board of the embodiment of the present application.

[0033] Figure 7 The circuit diagram of the strip line of the antenna feeding printed board of the embodiment of the present application.

[0034] Figure 8 The standing wave ratio curve of the two polarization ports of the antenna of the embodiment of the present application.

[0035] Figure 9 The isolation curve of the two polarization ports of the antenna of the embodiment of the present application.

[0036] Figure 10 The directional diagram curve when the left-handed circular polarization port of the antenna of the embodiment of the present application is excited.

[0037] Figure 11 The directional diagram curve when the right-handed circular polarization port of the antenna of the embodiment of the present application is excited.

[0038] The meaning represented by the mark in the figure:

[0039] Waveguide cavity 1, first cavity lower part 11, narrow edge slot 111, narrow edge slot disturbance block 112, first feed slot 113, second cavity lower part 12, wide edge slot 121, wide edge slot disturbance block 122, second feed slot 123, cavity upper part 13, cavity lower part 14, waveguide wall 15, ridge 16, partition plate 17, feed opening 161, feed printed board 2, third feed slot 21, fourth feed slot 22, mounting hole 23, left-handed circular polarization port connector 24, right-handed circular polarization port connector 25, strip line 26, upper layer metal surface 27, metal shielding hole 28, lower layer metal surface 29, electric bridge 261, "T" shaped power division 262, "L" shaped slot coupling matching section 263, phase compensation section 264, "H" shaped slot coupling matching section 265, mounting screw 3. DETAILED DESCRIPTION

[0040] The present application aims to provide a light and thin waveguide slot antenna with integrated feeding network, which has the advantages of compact structure, easy processing and assembly, low profile, light weight and low cost.

[0041] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the accompanying drawings. The embodiments of the present application are shown in the drawings. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0042] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing particular embodiments only and is not intended to be limiting of the application.

[0043] The embodiment relates to a light and thin waveguide slot antenna, which comprises a waveguide cavity 1 and a feeding printed board 2. The waveguide cavity 1 is composed of a rectangular waveguide cavity and a ridge waveguide cavity. The rectangular waveguide cavity is provided with narrow-edge slots 111 and narrow-edge slot perturbation blocks 112, and the ridge waveguide cavity is provided with wide-edge slots 121 and wide-edge slot perturbation blocks 122. The feeding printed board 2 is a microwave strip line, and the strip line 26 comprises a bridge 261, a 'T' shaped power division 262, a phase compensation section 264, an 'L' shaped slot coupling matching section 263 and an 'H' shaped slot coupling matching section 265. The 'L' shaped slots and the 'H' shaped slots formed in the bottom of the waveguide cavity 1 correspond to the 'L' shaped slots and the 'H' shaped slots formed in the upper metal surface 27 of the feeding printed board 2 respectively, and serve as signal transmission channels.

[0044] As shown in the accompanying drawings, Figures 1-7 The light and thin waveguide slot antenna of the embodiment comprises the waveguide cavity 1, the feeding printed board 2 and the mounting screw 3. The feeding printed board 2 is located below the waveguide cavity 1 and is assembled with the waveguide cavity 1 through the mounting screw 3. Figure 4 As shown in the accompanying drawings,

[0045] During the antenna processing, the waveguide cavity 1 is divided into two parts, i.e., a cavity upper part 13 and a cavity lower part 14, and then the two parts are combined into one through welding.

[0046] The rear part of the cavity upper part 13 is higher than the front part by one step, and eight narrow-edge slots 111 perpendicular to the azimuth direction are formed on the rear part of the cavity upper part 13 along the azimuth direction. The narrow-edge slots 111 are uniformly distributed on the rear part of the cavity upper part 13. The narrow-edge slot perturbation blocks 112 are staggered and arranged on the upper and lower sides of the narrow-edge slots 111, and the narrow-edge slot perturbation blocks 112 are located on the two sides of the narrow-edge slots 111. The wide-edge slots 121 parallel to the azimuth direction are formed on the front part of the cavity upper part 13 along the azimuth direction, and the wide-edge slot perturbation blocks 122 are staggered and arranged on the two sides of the wide-edge slots 121. The narrow-edge slot perturbation blocks 112 and the wide-edge slot perturbation blocks 122 are located on the inner top surface of the cavity upper part 13. The interval between the wide-edge slots 121 is consistent with the interval between the narrow-edge slots 111, and the center line of each wide-edge slot 121 and the center line of the corresponding narrow-edge slot 111 are the same line.

[0047] As shown in the accompanying drawings, Figure 3 andFigure 4 As shown, the lower cavity portion 14 is a rectangular hollow cavity structure without a top surface. A waveguide wall 15 is provided in the middle of the lower cavity portion 14, parallel to the azimuth direction and perpendicular to the bottom surface of the lower cavity portion 14. The waveguide wall 15 is located at the interface between the front and rear portions of the upper cavity portion 13. The waveguide wall 15 divides the entire waveguide cavity 1 into a first waveguide cavity and a second waveguide cavity, and also divides the lower cavity portion 14 into a first cavity lower portion 11 and a second cavity lower portion 12. A partition 17 is provided in the middle of the lower cavity portion 14, perpendicular to the azimuth direction and the bottom surface of the lower cavity portion 14. The partition 17 divides the first waveguide cavity and the second waveguide cavity into left and right portions, respectively. The partition 17 intersects the waveguide wall 15 at right angles. The partition 17 divides the first waveguide cavity into left and right cavities along the azimuth direction, and the partition 17 divides the second waveguide cavity into left and right cavities along the azimuth direction.

[0048] The first waveguide cavity is a rectangular waveguide cavity, with the wide side of the waveguide running vertically and the narrow side running horizontally. A ridge 16 is provided on the lower portion 12 of the second cavity. Thus, the second waveguide cavity is a ridge waveguide cavity. The first and second waveguide cavities share a common wall, with waveguide wall 15 being a common wall between the first and second cavities.

[0049] The four narrow-side slots 111 distributed on the left side of the first waveguide cavity form the first sub-array. The first narrow-side slot perturbation block 112 is located at the left front and right rear, the second narrow-side slot perturbation block 112 is located at the left rear and right front, and so on. The four narrow-side slots 111 distributed on the right side of the first waveguide cavity form the second sub-array. The positions of the narrow-side slot perturbation blocks 112 are opposite to those of the narrow-side slot perturbation blocks 112 on the left side.

[0050] The ridge 16 of the lower portion 12 of the second cavity is parallel to the waveguide wall 15 and, together with the partition 17, divides the second waveguide cavity into four sections: the left front, left rear, right front, and right rear. In this embodiment, the four sections have the same volume. The broadside slots 121 described above are located directly above the ridge 16. The four broadside slots 121 in the left cavity form one subarray, and the four broadside slots 121 in the right cavity form another subarray. Of the four broadside slots 121 in the left cavity of the second waveguide cavity, the first broadside slot perturbation block 122 is located behind the first broadside slot 121, the second broadside slot perturbation block 122 is located in front of the second broadside slot 121, and so on. The positions of the four broadside slot perturbation blocks 122 in the right cavity of the second waveguide cavity are opposite to those of the broadside slot perturbation blocks 122 in the left cavity.

[0051] A first feeding slot 113 is formed on the left and right parts of the bottom of the first cavity lower part 11. The short side of the first feeding slot 113 is perpendicular to the azimuth and is located in the middle of the two narrow edge slots 111. The long side is parallel to the azimuth. The openings of the two first feeding slots 113 are reversed and both are away from the partition 17. The short side of the left first feeding slot 113 is located in the middle of the second and third narrow edge slots 111.

[0052] A second feeding slot 123 is formed on the left and right parts of the bottom of the second cavity lower part 12. The left second feeding slot 123 is located in the middle of the second and third wide edge slots 121. The short horizontal of the middle of the "H" shape of all the second feeding slots 123 is perpendicular to the ridge 16 and is symmetric about the ridge 16. The short horizontal is flush with the short side of the first feeding slot 113. As shown in the attached drawings, the second feeding slot 123 penetrates the ridge 16 of the second waveguide cavity from bottom to top. The width corresponding to the short side of the second feeding slot 123 is also removed to form a feeding opening 161 of the ridge 16 of the second waveguide cavity to realize the transmission of electromagnetic wave signals. Figure 5

[0053] The feeding printed board 2 is a microwave strip line structure and is composed of an upper metal surface 27 of the feeding printed board, a strip line 26 of the feeding printed board, a microwave dielectric plate and a lower metal surface 29 of the feeding printed board. When the feeding printed board 2 is installed, the upper metal surface 27 of the feeding printed board is attached to the bottom of the waveguide cavity 1.

[0054] As shown in the attached drawings, the upper metal surface 27 of the feeding printed board is etched with a third feeding slot 21 in the shape of "L" and a fourth feeding slot 22 in the shape of "H". The position, size and shape of the third feeding slot 21 correspond to those of the first feeding slot 113. The position, size and shape of the fourth feeding slot 22 correspond to those of the second feeding slot 123. When installed, the third feeding slot 21 and the fourth feeding slot 22 are aligned and installed. Figure 6 The upper metal surface 27 of the feeding printed board and the lower metal surface 29 of the feeding printed board are interconnected through metal shielding holes 28 which are uniformly distributed on both sides of the strip line 26 of the feeding printed board. The strip line 26 of the feeding printed board includes an electric bridge 261 of the feeding strip line, a "T" shape power division 262 of the feeding strip line, an "L" shape slot coupling matching section 263 of the feeding strip line, a phase compensation section 264 of the feeding strip line and an "H" shape slot coupling matching section 265 of the feeding strip line. The left-hand circularly polarized port connector 24 and the right-hand circularly polarized port connector 25 are welded on the lower metal surface 29 of the feeding printed board.

[0055]

[0056] ​​The L-shaped slot coupling and matching section 263 is located directly below the third feed slot 21. The H-shaped slot coupling and matching section 265 is located directly below the fourth feed slot 22. Both coupling and matching sections function as excitation slots and impedance matching. The feed stripline phase compensation section 264 adjusts the phase difference between the first and second waveguide cavities.

[0057] Taking left-hand circularly polarized port excitation as an example, the signal is first fed into the left-hand circularly polarized port connector 24, and after passing through the feed strip line bridge 261, it is divided into two groups of upper and lower signals with a phase difference of 90°. After passing through the upper and lower feed strip line "T"-shaped power splitters 262, it is transmitted to the left and right sides. The signal passes through the L"-shaped feeding slot 21 and the "H"-shaped feeding slot 22, and then enters the waveguide cavity 1 through the waveguide cavity "L"-shaped feeding slot 113 and the waveguide cavity "H"-shaped feeding slot 123. Finally, it radiates into free space through the wide side slot 121 and the narrow side slot 111. Since the phase difference between the radiated signals of the wide side slot 121 and the narrow side slot 111 is 90°, the signal is synthesized into a left-hand circularly polarized wave.

[0058] The feed printed board 2 is provided with mounting holes 23 and is mounted to the waveguide cavity 1 by mounting screws 3. When the feed printed board 2 is mounted, the upper metal surface 27 of the feed printed board is attached to the bottom of the waveguide cavity 1.

[0059] As attached Figure 4 As shown, during the antenna manufacturing process, the waveguide cavity 1 is divided into two parts, namely the cavity upper part 13 and the cavity lower part 14, and then the two parts are combined into one by welding.

[0060] The port standing wave ratio curve and isolation performance results of a lightweight waveguide slot antenna in this embodiment are shown in the attached figure. Figure 8 and Figure 9 The antenna operates at frequencies fL~fH with a center frequency of f0. Within the operating bandwidth of fL~fH, the standing wave ratio is less than 2, and the isolation between the two polarizations is less than -20dB.

[0061] Attachment Figure 10 and Figure 11 They are the main polarization pattern and cross-polarization pattern in the azimuth direction when the left-hand circularly polarized port and the right-hand circularly polarized port of this embodiment are excited, respectively. The antenna has excellent directional pattern performance. The amplitude of the cross-polarization in the 0° direction is much lower than the amplitude of the main polarization, indicating that the antenna has good circular polarization performance.

[0062] The dual circularly polarized waveguide slot antenna of the embodiment has the advantages of simple cavity structure and low processing cost, and can meet the needs of multifunctional radar, wireless communication and other applications. In the embodiment, the waveguide cavity is divided into left and right cavities in the azimuth direction, and four slots are arranged in each of the left and right cavities. Arranging the waveguide cavity into cavities of other numbers in the azimuth direction, or providing other numbers of slots above the cavities, or forming a larger array antenna by the dual circularly polarized waveguide slot antenna provided by the application, are also within the protection scope of the application.

[0063] The application can achieve the following effects:

[0064] 1. Simple waveguide cavity structure: The waveguide cavity in the application adopts a single-layer rectangular waveguide cavity and a ridge waveguide cavity, and the rectangular waveguide cavity and the ridge waveguide cavity share a wall. The waveguide cavity is divided into two parts during processing, and only one welding is needed, so the processing difficulty is reduced.

[0065] 2. Low profile and light weight: The antenna in the application adopts a form of one cavity plus a feeding printed board, and the profile is lower than that of the traditional waveguide slot antenna. The antenna profile height and weight are reduced.

[0066] 3. New feeding form: The antenna in the application adopts an L-shaped coupling feeding slot, an H-shaped coupling feeding slot and a coupling feeding strip line, and realizes the broadband working performance of the antenna. Compared with the coaxial probe feeding form of the traditional waveguide slot antenna, the matching block for inserting the coaxial connector does not need to be processed in the waveguide cavity, and the loss introduced by the coaxial feeding is reduced.

[0067] 4. Integration of antenna and feeding network: The antenna in the application has high integration, and the dual circularly polarized electric bridge and the power division network are integrated in the feeding printed board, so that the dual circularly polarized working and the integration design of multiple waveguide slot subarrays can be realized.

[0068] Based on the above considerations, a dual circularly polarized waveguide slot antenna is developed, which has a simple cavity structure and has the advantages of low profile, light weight and easy processing and integration.

[0069] The above description is only the preferred embodiment of the application, and is not intended to limit the application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the application shall be included in the protection scope of the application.

Claims

1. A lightweight waveguide slot antenna, characterized in that: The invention comprises a waveguide cavity (1) and a feed printed circuit board (2), wherein the feed printed circuit board (2) is located below the waveguide cavity (1); a waveguide wall (15) is provided in the waveguide cavity (1), and the waveguide wall (15) divides the waveguide cavity of the entire waveguide cavity (1) into a first waveguide cavity and a second waveguide cavity, wherein the first waveguide cavity is a rectangular waveguide cavity and the second waveguide cavity is a ridge waveguide cavity; the waveguide wall (15) is located in the middle of the lower part (14) of the cavity, and the waveguide wall (15) is parallel to the azimuth direction and perpendicular to the bottom surface of the lower part (14) of the cavity; The waveguide cavity (1) is assembled from two parts, namely, a cavity upper part (13) and a cavity lower part (14); the waveguide wall (15) divides the cavity lower part (14) into a first cavity lower part (11) and a second cavity lower part (12); the left and right parts of the bottom of the first cavity lower part (11) are each provided with an "L"-shaped first feeding slot (113); the left and right parts of the bottom of the second cavity lower part (12) are each provided with an "H"-shaped second feeding slot (123); the rear part of the cavity upper part (13) is one step higher than the front part; the rear part of the cavity upper part (13) is provided with 2n narrow side slots (111) perpendicular to the azimuth direction along the azimuth direction, and the narrow side slots (111) are evenly distributed on the rear part of the cavity upper part (13); the front part of the cavity upper part (13) is provided with 2n wide side slots parallel to the azimuth direction along the azimuth direction. Slot (121), wherein n is a positive even number; an upper metal surface (27) of the feed printed board is etched with an "L"-shaped third feed slot (21) and an "H"-shaped fourth feed slot (22); the position, size and shape of the third feed slot (21) correspond one-to-one to the first feed slot (113), and the position, size and shape of the fourth feed slot (22) correspond one-to-one to the second feed slot (123), forming a signal transmission channel; the feed printed board (2) is a microwave stripline structure, and further includes a stripline (26), a microwave dielectric plate, a lower metal surface (29), a left-handed circularly polarized port connector (24) and a right-handed circularly polarized port connector (25); the stripline (26) includes a bridge (261), a "T"-shaped power splitter (262), an "L"-shaped slot coupling and matching section (263), a phase compensation section (264) and an "H"-shaped slot coupling and matching section (265).

2. The lightweight waveguide slot antenna according to claim 1, wherein: Narrow-side gap disturbance blocks (112) are arranged alternately up and down on both sides of the narrow-side gap (111), and the narrow-side gap disturbance blocks (112) are located on both sides of the narrow-side gap (111); wide-side gap disturbance blocks (122) are arranged alternately on both sides of the wide-side gap (121); and the narrow-side gap disturbance blocks (112) and the wide-side gap disturbance blocks (122) are both located on the inner top surface of the upper portion (13) of the cavity.

3. The lightweight waveguide slot antenna according to claim 1, wherein: The spacing between the wide side slits (121) is consistent with the spacing between the narrow side slits (111), and the center line of each wide side slit (121) and the center line of the corresponding narrow side slit (111) are the same line.

4. The lightweight waveguide slot antenna according to claim 1, wherein: The lower cavity part (14) is a rectangular parallelepiped cavity structure without a top surface, and the waveguide wall (15) is located on the interface between the front part and the rear part of the upper cavity part (13).

5. The lightweight waveguide slot antenna according to claim 1, wherein: A partition (17) perpendicular to the azimuth direction and perpendicular to the bottom surface of the lower cavity part (14) is provided in the middle of the lower cavity part (14), and the partition (17) divides the first waveguide cavity and the second waveguide cavity into two left and right parts respectively; the partition (17) intersects the waveguide wall (15) perpendicularly; the partition (17) divides the first waveguide cavity into two left and right cavities along the azimuth direction, and the partition (17) divides the second waveguide cavity into two left and right cavities along the azimuth direction.

6. The lightweight waveguide slot antenna according to claim 5, characterized in that: The lower portion (12) of the second cavity is provided with a ridge (16), the ridge (16) of the lower portion (12) of the second cavity is parallel to the waveguide wall (15), and together with the partition (17), the second waveguide cavity is divided into four parts: left front, left rear, right front, and right rear; the wide side gap (121) is located directly above the ridge (16).

7. The lightweight waveguide slot antenna according to claim 6, characterized in that: The short sides of the two first feeding slots (113) are perpendicular to the azimuth direction and are respectively located at the bottom of the lower part (11) of the first cavity. and The middle of the narrow side gap (111), the bottom of the first cavity lower part (11) and In the middle of the narrow side slot (111), the long sides of the two first feeding slots (113) are parallel to the azimuth direction, and the "L"-shaped openings of the two first feeding slots (113) are opposite and both face away from the partition (17); The two second feeding slots (123) are respectively located at the bottom of the second cavity lower part (12). and The middle of the wide side gap (121), the bottom of the first cavity lower part (11) and In the middle of each wide side slot (121), the short horizontal line in the middle of the "H" shape of all second feed slots (123) is perpendicular to the ridge (16) and symmetrical about the ridge (16); The second feeding slot (123) penetrates the ridge (16) of the second waveguide cavity from bottom to top, forming a feeding opening (161) of the ridge (16) of the second waveguide cavity to achieve transmission of electromagnetic wave signals.

8. The lightweight waveguide slot antenna according to claim 2, wherein: The n narrow-side slots (111) distributed on the left cavity of the first waveguide cavity form a sub-array, the position of the first narrow-side slot perturbation block (112) is left front and right rear, the position of the second narrow-side slot perturbation block (112) is left rear and right front, and so on; the n narrow-side slots (111) distributed on the right cavity of the first waveguide cavity form another sub-array, the position of the narrow-side slot perturbation block (112) is opposite to the position of the narrow-side slot perturbation block (112) on the left cavity; The n wide-side slots (121) distributed in the left cavity of the second waveguide cavity form a group of sub-arrays, and the n wide-side slots (121) distributed in the right cavity form another group of sub-arrays; among the n wide-side slots (121) in the left cavity of the second waveguide cavity, the first wide-side slot perturbation block (122) is located behind the first wide-side slot (121), the second wide-side slot perturbation block (122) is located in front of the second wide-side slot (121), and so on; the positions of the n wide-side slot perturbation blocks (122) in the right cavity of the second waveguide cavity are opposite to those of the wide-side slot perturbation blocks (122) in the left cavity.

9. The lightweight waveguide slot antenna according to claim 1, wherein: The left-hand circular polarization port connector (24) and the right-hand circular polarization port connector (25) are arranged on the lower metal surface (29) of the feed printed circuit board.

10. The lightweight waveguide slot antenna according to claim 9, characterized in that: The "L"-shaped slot coupling matching section (263) is located directly below the third feeding slot (21); the "H"-shaped slot coupling matching section (265) is located directly below the fourth feeding slot (22); both the "L"-shaped slot coupling matching section (263) and the "H"-shaped slot coupling matching section (265) play the role of exciting the slot and impedance matching; the feeding strip line phase compensation section (264) is used to adjust the phase difference between the first waveguide cavity and the second waveguide cavity.

11. The lightweight waveguide slot antenna according to claim 10, characterized in that: The upper metal surface (27) and the lower metal surface (29) are interconnected through metal shielding holes (28), and the metal shielding holes (28) are evenly distributed on both sides of the strip line (26); the feed printed board (2) also includes mounting screws (3), and the feed printed board (2) is provided with a plurality of mounting holes (23), and the mounting screws (3) pass through the mounting holes (23) to mount the feed printed board (2) and the waveguide cavity (1); when the feed printed board (2) is installed, the upper metal surface (27) of the feed printed board is attached to the bottom of the waveguide cavity (1).

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