A dual-polarized monopulse waveguide slot antenna array

Abstract

A dual-polarization single-pulse waveguide slot antenna array comprises: a metal reflector, a horizontal polarization waveguide port radiation array and a vertical polarization waveguide port radiation array, which are sequentially arranged from top to bottom, a horizontal polarization waveguide power synthesis network connected to the horizontal polarization waveguide port radiation array, a vertical polarization waveguide power synthesis network connected to the vertical polarization waveguide port radiation array, a horizontal polarization sum difference network connected to the horizontal polarization waveguide power synthesis network, and a vertical polarization sum difference network connected to the vertical polarization waveguide power synthesis network. The present invention has a radiation efficiency comparable to that of a single-polarization single-pulse antenna, as well as lower side lobes, and reduces the coupling effect of two polarization signals, has both miniaturization and dual-polarization characteristics, and has an ingenious layout, can meet the requirements of composite and compatible coplanar dual-polarization antenna arrays, and has strong practicality and application prospects.

Description

Technical Field

[0001] The present invention relates to the field of antenna design, and in particular to a dual-polarization monopulse waveguide slot antenna array. Background Art

[0002] Dual-polarized antennas have been widely used in radar, electronic countermeasures, aerospace, and other systems. For example, in SAR systems, by leveraging the different scattering characteristics of ground objects for electromagnetic waves of different polarizations, a dual-polarized operating mode can be used to obtain rich ground object information, thereby better distinguishing and identifying ground objects. In satellite communication systems, dual-polarized antennas can transmit two signals of different polarizations within the same bandwidth, conserving frequency resources and doubling frequency band utilization.

[0003] Previous research on dual-polarized planar antenna arrays has primarily focused on microstrip antenna arrays. For example, dual-polarized microstrip patch antennas utilize a double-layer radiating patch to achieve dual polarization, but this results in relatively narrow bandwidth. Alternatively, two radiating patches operating in the primary mode are nested together, but this requires a large ratio of inner to outer patch sizes and often requires loading capacitors. Alternatively, a multi-layer stacked microstrip patch structure can achieve wider bandwidth and higher polarization isolation. As is well known, microstrip patch antennas suffer from high insertion loss and low antenna efficiency at higher frequencies. Summary of the Invention

[0004] The purpose of the present invention is to provide a dual-polarized monopulse waveguide slot antenna array, which has a radiation efficiency comparable to that of a single-polarized monopulse antenna, as well as lower side lobes, and reduces the coupling effect of the two polarized signals. It has both miniaturization and dual-polarization characteristics, and an ingenious layout. It can meet the requirements of the combination and compatibility of coplanar dual-polarized antenna arrays, and has strong practicality and application prospects.

[0005] In order to achieve the above object, the present invention provides a dual-polarization monopulse waveguide slot antenna array, comprising:

[0006] Metal reflective panels;

[0007] A horizontally polarized waveguide port radiation array and a vertically polarized waveguide port radiation array, which are arranged below the metal reflector;

[0008] a horizontally polarized waveguide power combining network, which is arranged below the horizontally polarized waveguide port radiation array and connected to the horizontally polarized waveguide port radiation array;

[0009] A vertical polarization waveguide power combining network is provided below the vertical polarization waveguide port radiation array and is connected to the vertical polarization waveguide port radiation array;

[0010] a horizontal polarization sum and difference network, which is arranged below the horizontal polarization waveguide power combining network and connected to the horizontal polarization waveguide power combining network;

[0011] A vertical polarization sum and difference network is arranged below the vertical polarization waveguide power synthesis network and connected to the vertical polarization waveguide power synthesis network.

[0012] The horizontally polarized waveguide port radiation array and the vertically polarized waveguide port radiation array each include four regions, and the multiple waveguide port radiation arrays in adjacent regions are arranged in a symmetrical manner in the horizontal and vertical directions;

[0013] The horizontally polarized waveguide port radiation array comprises a plurality of mutually parallel first waveguide port antennas, and the center distance between any two adjacent first waveguide port antennas is half the waveguide wavelength;

[0014] The vertically polarized waveguide port radiation array comprises a plurality of mutually parallel second waveguide port antennas, and the center distance between any two adjacent second waveguide port antennas is half the waveguide wavelength;

[0015] The first waveguide port antenna and the second waveguide port antenna are placed at 90 degrees.

[0016] The current distribution of the first waveguide antenna adopts Taylor distribution. The first waveguide antenna is flanged at the bottom to form a first waveguide flange structure. A metal spacer is provided in the first waveguide antenna for impedance matching.

[0017] The current distribution of the second waveguide antenna adopts Taylor distribution, and the second waveguide antenna has a second waveguide flange structure.

[0018] The horizontally polarized waveguide power combining network comprises four regions, which respectively correspond to the four regions in the horizontally polarized waveguide port radiation array;

[0019] The horizontally polarized waveguide power combining network comprises a four-layer waveguide structure;

[0020] The first waveguide layer includes a plurality of first waveguides arranged parallel to each other, each first waveguide being connected to a corresponding first waveguide port antenna. A plurality of first oblique slots are formed on the upper surface of each first waveguide, and the number of the first oblique slots is the same as the number of the first waveguide port antennas.

[0021] A second waveguide is formed at the end of the first waveguide using a 90-degree bend structure, and all the second waveguides constitute a second layer of waveguide;

[0022] The third waveguide layer includes at least two third waveguides arranged parallel to each other, the third waveguides being arranged perpendicular to the second waveguides, a plurality of second oblique slits being formed on the upper surface of each third waveguide, the third waveguides being connected to the second waveguides via the second oblique slits, and the number of the second oblique slits being the same as the number of the second waveguides;

[0023] The fourth waveguide layer includes at least one fourth waveguide. A plurality of third oblique slots are provided on the upper surface of the fourth waveguide, which are respectively connected to the third waveguides through the third oblique slots. The number of the third oblique slots is the same as the number of the third waveguides.

[0024] The vertical polarization waveguide power combining network comprises four regions, which respectively correspond to the four regions in the vertical polarization waveguide port radiation array;

[0025] The vertically polarized waveguide power combining network comprises a three-layer waveguide structure;

[0026] The first waveguide layer includes multiple fifth waveguides arranged in parallel with each other, with the middle fifth waveguide shared by the four quadrants. Each fifth waveguide is connected to a corresponding second waveguide port antenna, and a 90-degree bend structure is used at the end of the fifth waveguide to connect to the lower waveguide. The upper surface of each fifth waveguide is provided with multiple coupling slits, and the number of the coupling slits is the same as the number of the second waveguide port antennas.

[0027] A sixth waveguide parallel to the fifth waveguide is connected to the 90-degree bend structure at the end of the fifth waveguide, and all the sixth waveguides constitute a second layer of waveguides;

[0028] The third layer of waveguide includes at least one seventh waveguide, which is perpendicular to the sixth waveguide. The upper surface of the seventh waveguide is provided with a feeding slit, which is connected to the sixth waveguide through the feeding slit. The number of the feeding slits is the same as the number of the sixth waveguides.

[0029] Normalized resistance r of all inclined slits jk and the tilt angle θ jk for:

[0030]

[0031] Where, P jk is the radiation power of the Kth inclined slot on the jth waveguide, β=2π / λ g , λ is the free space wavelength, λg is the waveguide wavelength, a and b are the width and height of the waveguide, I jk is the current distribution of the Kth inclined slot on the jth waveguide, which is obtained by the -30dB Taylor distribution.

[0032] The normalized resistance of the slanted slots on the first waveguide and the fifth waveguide satisfies:

[0033]

[0034] The horizontal polarization sum and difference network includes four waveguide magic Ts, which respectively output the sum signal, E-plane difference signal, and H-plane difference signal of the four areas of the horizontal polarization waveguide power synthesis network.

[0035] The vertical polarization sum and difference network includes four waveguide magic Ts, which respectively output the sum signal, E-plane difference signal, and H-plane difference signal of the four regions of the vertical polarization waveguide power synthesis network, and use an adjustment block to adjust the impedance matching.

[0036] The present invention provides a miniaturized, coplanar, dual-polarization composite monopulse array antenna with a common aperture and an ingenious structure. This antenna utilizes a method of sharing the same aperture for horizontal and vertical polarizations to improve aperture utilization efficiency. Both horizontal and vertical polarizations utilize waveguide feeding, reducing feed network losses and achieving high antenna efficiency. The two polarizations of the radiating elements utilize the same polarization feeding method, with direct feeding for vertical polarization and vertical polarization feeding for horizontal polarization. Horizontal polarization of the radiation is achieved through waveguide step transitions and slot coupling. The current distribution of the antenna elements utilizes a Taylor distribution, which controls the amplitude of each waveguide antenna by adjusting the tilt angle of the tilted slots located at the bottom of the waveguide aperture, thereby achieving low sidelobes and comparable radiation efficiency to a single-polarization monopulse antenna. Furthermore, designs such as polarization spacers reduce the coupling effect of the two polarizations and reduce far-field sidelobes. Therefore, the coplanar composite monopulse array antenna provided by the present invention has both miniaturization and dual-polarization characteristics, and has a clever layout. It can meet the requirements of composite and compatibility of two polarized antenna arrays in space, is easy to process, and has strong practicality and application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the three-dimensional structure of the dual-polarization single-pulse waveguide slot antenna array provided by the present invention.

[0038] Figure 2 It is a side view of the dual-polarization monopulse waveguide slot antenna array provided by the present invention.

[0039] Figure 3 It is a top view of the horizontally polarized waveguide port radiation array and the vertically polarized waveguide port radiation array.

[0040] Figure 4 It is a schematic diagram of the three-dimensional structure of the first waveguide antenna.

[0041] Figure 5 It is a schematic diagram of the three-dimensional structure of the second waveguide antenna.

[0042] Figure 6 This is the front view of the horizontally polarized waveguide power combining network.

[0043] Figure 7 It is a side view of the horizontally polarized waveguide power combining network.

[0044] Figure 8 It is a top view of the first oblique slit.

[0045] Figure 9 It is a top view of the second oblique slit.

[0046] Figure 10 This is the front view of the vertically polarized waveguide power combining network.

[0047] Figure 11 This is a side view of the vertically polarized waveguide power combining network.

[0048] Figure 12 It is a top view of the coupled oblique slit.

[0049] Figure 13 This is a top view of the feed slant slot.

[0050] Figure 14 This is a top view of the sum and difference network.

[0051] Figure 15 It is a top view of the horizontal polarization sum difference network.

[0052] Figure 16 It is a top view of the vertical polarization and difference network.

[0053] Figure 17 is the horizontally polarized radiation pattern.

[0054] Figure 18 is the vertically polarized radiation pattern. DETAILED DESCRIPTION

[0055] The following is based on Figures 1 to 18 , specifically describe the preferred embodiments of the present invention.

[0056] Compared to microstrip antennas, waveguide slot antennas have advantages such as easy control of aperture field distribution, high aperture efficiency, stable performance, good structural strength, and easy realization of narrow beam and low sidelobe. Therefore, the study of dual-polarization waveguide slot antennas has important application value.

[0057] like Figure 1 and Figure 2 As shown, in one embodiment of the present invention, the present invention provides a dual-polarization monopulse waveguide slot antenna array, comprising:

[0058] A metal reflector plate 7 having a plurality of waveguide openings;

[0059] A horizontally polarized waveguide port radiation array 1 and a vertically polarized waveguide port radiation array 2 are arranged below the metal reflector 7. The horizontally polarized waveguide port radiation array 1 and the vertically polarized waveguide port radiation array 2 are arranged on the top of the dual-polarized monopulse waveguide slot antenna array;

[0060] a horizontally polarized waveguide power combining network 3, which is arranged below the horizontally polarized waveguide port radiation array 1 and connected to the horizontally polarized waveguide port radiation array 1;

[0061] A vertical polarization waveguide power combining network 4 is provided below the vertical polarization waveguide port radiation array 2 and is connected to the vertical polarization waveguide port radiation array 2;

[0062] a horizontal polarization sum and difference network 5, which is arranged below the horizontal polarization waveguide power combining network 3 and connected to the horizontal polarization waveguide power combining network 3;

[0063] The vertical polarization sum and difference network 6 is arranged below the vertical polarization waveguide power combining network 4 and is connected to the vertical polarization waveguide power combining network 4 .

[0064] In this embodiment, the layers of the dual-polarization monopulse waveguide slot antenna array are connected by welding.

[0065] Further, if Figure 3 As shown, in order to form a difference beam, the horizontally polarized waveguide mouth radiation array 1 and the vertically polarized waveguide mouth radiation array 2 are evenly divided into four axially symmetrical regions 01-04, and the multiple waveguide mouth radiation arrays in adjacent regions are arranged axially symmetrically, that is, the multiple waveguide mouth radiation arrays in the four regions are axially symmetrical to each other in the horizontal and vertical directions.

[0066] The horizontally polarized waveguide port radiation array 1 includes 236 mutually parallel first waveguide port antennas 11, that is, each quarter array plane includes 59 first waveguide port antennas 11, and the center distance between any two adjacent first waveguide port antennas 11 is half the waveguide wavelength.

[0067] The vertically polarized waveguide port radiation array 2 includes 254 mutually parallel second waveguide port antennas 21, wherein the 18 second waveguide port antennas 21 on the antenna axis are common to the four quadrants, and the center distance between any two adjacent second waveguide port antennas 21 is half the waveguide wavelength.

[0068] The first waveguide port antenna 11 and the second waveguide port antenna 21 are placed at 90 degrees to serve as radiating units of a horizontally polarized waveguide port radiating array and a vertically polarized waveguide port radiating array, respectively.

[0069] like Figure 4As shown, the current distribution of the first waveguide antenna 11 adopts Taylor distribution. For the convenience of feeding, the first waveguide antenna 11 is directly flanged at the bottom to form a waveguide flange structure 13. A metal spacer 12 is provided in the first waveguide antenna 11 for impedance matching.

[0070] like Figure 5 As shown, the current distribution of the second waveguide antenna 21 adopts Taylor distribution. In order to facilitate antenna layout and avoid interference with the first waveguide antenna 11, the second waveguide antenna 21 adopts a waveguide flange structure 22.

[0071] like Figure 6 and Figure 7 As shown, the horizontally polarized waveguide power combining network 3 is also divided into four regions 01-04 axially symmetrically, corresponding to the four regions in the horizontally polarized waveguide port radiation array 1. In order to save space, the horizontally polarized waveguide power combining network 3 comprises a four-layer waveguide structure. In one-quarter of the sub-array, the first waveguide layer comprises eight first waveguides 31 arranged parallel to each other. Each first waveguide 31 is connected to a corresponding first waveguide port antenna 11. The upper surface of each first waveguide 31 is provided with a plurality of first oblique slots 35 (such as Figure 8 As shown in FIG, the number of the first oblique slots 35 is the same as the number of the first waveguide port antennas 11 connected to the first waveguide 31. A second waveguide 32 is formed at the end of the first waveguide 31 by a 90-degree bend structure. All the second waveguides 32 constitute the second waveguide layer. The third waveguide layer includes two third waveguides 33 arranged parallel to each other. The third waveguides 33 are arranged perpendicular to the second waveguides 32. The upper surface of each third waveguide 33 is provided with a second oblique slot 36 (as shown in FIG. Figure 9 ), which are connected to the second waveguides 32 via second slanted slits 36, and the number of the second slanted slits 36 is the same as the number of the second waveguides 32. The fourth waveguide layer includes one fourth waveguide 34, and the upper surface of the fourth waveguide 34 is provided with a third slanted slit 37, which is connected to each third waveguide 33 via the third slanted slit 37, and the number of the third slanted slits 37 is the same as the number of the third waveguides 33.

[0072] like Figure 10 and Figure 11As shown, the vertical polarization waveguide power synthesis network 4 is also divided into four areas 01-04 axially symmetrically, corresponding to the four areas in the vertical polarization waveguide mouth radiation array 2, and the four quadrants share the middle antenna axis. In order to save space, the vertical polarization waveguide power synthesis network 4 includes a three-layer waveguide structure. In one-quarter sub-array, the first layer of waveguide includes 9 fifth waveguides 41 arranged in parallel with each other, of which the middle waveguide is shared by the four quadrants. Each fifth waveguide 41 is respectively connected to the corresponding second waveguide mouth antenna 21, and a 90-degree bend structure 46 is used at the end of the fifth waveguide 41 to connect to the lower waveguide. The upper surface of each fifth waveguide 41 is provided with a plurality of coupling slits 44 ( Figure 12 As shown), the number of the coupling slits 44 is the same as the number of the second waveguide port antennas 21 connected to the fifth waveguide 41. The second waveguide layer is a flange structure parallel to the fifth waveguide 41, namely the sixth waveguide 42. The third waveguide layer includes a seventh waveguide 43, which is perpendicular to the sixth waveguide 42. The upper surface of the seventh waveguide 43 is provided with a feeding slit 45 (as shown). Figure 13 As shown), they are connected to the sixth waveguide 42 through the feeding oblique slots 45 respectively.

[0073] The tapering of the azimuth plane and the elevation plane of the horizontally polarized waveguide mouth radiation array 1 and the vertically polarized waveguide mouth radiation array 2 are respectively achieved by the slanted slots on the waveguide, and the length and tilt (rotation) angle of the slanted slots determine the current distribution of each waveguide mouth antenna.

[0074] The normalized resistance and tilt angle of the slanted slit can be obtained from the following formula:

[0075]

[0076] Where, P jk is the radiation power of the Kth inclined slot on the jth waveguide, β=2π / λ g , where λ is the free space wavelength, λg is the waveguide wavelength, a and b are the width and height of the waveguide, I jk is the current distribution of the Kth inclined slot on the jth waveguide, which can be obtained by the -30dB Taylor distribution.

[0077] In order to achieve matching in each coupled waveguide (the first waveguide 31 and the fifth waveguide 41), the normalized resistance of each slot should satisfy:

[0078]

[0079] like Figure 14 As shown, the monopulse array antenna sum and difference network consists of a horizontal polarization sum and difference network 5 and a vertical polarization sum and difference network 6.

[0080] like Figure 15As shown, the horizontal polarization sum-difference network 5 includes four waveguide magic Ts 51-54. The output signal of output port 55 is the sum signal of the four quadrants 01+02+03+04; the output signal of output port 56 is the E-plane difference signal of the four quadrants 01+02-03-04; the output signal of output port 57 is the H-plane difference signal of the four quadrants 01+03-02-04; and the output port 58 is connected to a matched load.

[0081] like Figure 16 As shown, the vertically polarized sum-difference network 6 includes four waveguide magic Ts 61-64. To adjust the port standing wave coefficient, an adjustment block 70 is used to adjust the impedance matching of the sum-difference device. The output signal of output port 66 is the sum signal of the four quadrants 01+02+03+04; the output signal of output port 67 is the E-plane difference signal of the four quadrants 01+02-03-04; the output signal of output port 68 is the H-plane difference signal of the four quadrants 01+03-02-04; and the output signal of output port 69 is connected to a matched load.

[0082] Figure 17 It is a horizontally polarized sum-differential radiation pattern antenna. The maximum E-plane sum beam gain is 29.84dB, the E-plane sidelobe level is -27.3dB, the 3dB beamwidth is 4.83°, and the E-plane difference beam null depth is -40dB; the maximum H-plane sum beam gain is 29.8dB, the H-plane sidelobe level is -25.74dB, the 3dB beamwidth is 4.19°, and the H-plane difference beam null depth is -41dB.

[0083] Figure 18 It is a vertically polarized sum-differential radiation pattern antenna. The maximum E-plane sum beam gain is 29.26dB, the E-plane sidelobe level is -24.01dB, the 3dB beamwidth is 4.65°, and the E-plane difference beam null depth is -31.85dB; the maximum H-plane sum beam gain is 29.2dB, the H-plane sidelobe level is -25.5dB, the 3dB beamwidth is 4.27°, and the H-plane difference beam null depth is -33.08dB.

[0084] The present invention provides a miniaturized, coplanar, dual-polarization composite monopulse array antenna with a common aperture and an ingenious structure. This antenna utilizes a method of sharing the same aperture for horizontal and vertical polarizations to improve aperture utilization efficiency. Both horizontal and vertical polarizations utilize waveguide feeding, reducing feed network losses and achieving high antenna efficiency. The two polarizations of the radiating elements utilize the same polarization feeding method, with direct feeding for vertical polarization and vertical polarization feeding for horizontal polarization. Horizontal polarization of the radiation is achieved through waveguide step transitions and slot coupling. The current distribution of the antenna elements utilizes a Taylor distribution, which controls the amplitude of each waveguide antenna by adjusting the tilt angle of the tilted slots located at the bottom of the waveguide aperture, thereby achieving low sidelobes and comparable radiation efficiency to a single-polarization monopulse antenna. Furthermore, designs such as polarization spacers reduce the coupling effect of the two polarizations and reduce far-field sidelobes. Therefore, the coplanar composite monopulse array antenna provided by the present invention has both miniaturization and dual-polarization characteristics, and has a clever layout. It can meet the requirements of composite and compatibility of two polarized antenna arrays in space, is easy to process, and has strong practicality and application prospects.

[0085] It should be noted that, in the embodiments of the present invention, the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the embodiments, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance.

[0086] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0087] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description is not intended to limit the present invention. After reading the above description, various modifications and substitutions of the present invention will become apparent to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A dual-polarized monopulse waveguide slot antenna array, characterized in that: Include: Metal reflective panels; A horizontally polarized waveguide port radiation array and a vertically polarized waveguide port radiation array, which are arranged below the metal reflection plate; A horizontally polarized waveguide power synthesis network, which is arranged below the horizontally polarized waveguide port radiation array and connected to the horizontally polarized waveguide port radiation array; A vertical polarization waveguide power synthesis network, which is arranged below the vertical polarization waveguide port radiation array and connected to the vertical polarization waveguide port radiation array; A horizontal polarization sum and difference network, which is arranged below the horizontal polarization waveguide power synthesis network and connected to the horizontal polarization waveguide power synthesis network; A vertical polarization sum and difference network, which is arranged below the vertical polarization waveguide power synthesis network and connected to the vertical polarization waveguide power synthesis network; The horizontally polarized waveguide port radiation array and the vertically polarized waveguide port radiation array each include four regions, and the multiple waveguide port radiation arrays in adjacent regions are arranged in a symmetrical manner in the horizontal and vertical directions; The horizontally polarized waveguide port radiation array comprises a plurality of mutually parallel first waveguide port antennas, and the center distance between any two adjacent first waveguide port antennas is half the waveguide wavelength; The vertically polarized waveguide port radiation array comprises a plurality of second waveguide port antennas parallel to each other, and the center distance between any two adjacent second waveguide port antennas is half the waveguide wavelength; The first waveguide port antenna and the second waveguide port antenna are placed at 90 degrees; The horizontally polarized waveguide power synthesis network comprises four regions, which respectively correspond to the four regions in the horizontally polarized waveguide port radiation array; The horizontally polarized waveguide power synthesis network comprises a four-layer waveguide structure; The first layer of waveguide includes a plurality of first waveguides arranged in parallel with each other, each first waveguide is respectively connected to a corresponding first waveguide port antenna, a plurality of first oblique slots are opened on the upper surface of each first waveguide, and the number of the first oblique slots is the same as the number of the first waveguide port antennas; A second waveguide is formed at the end of the first waveguide by using a 90-degree bending structure, and all the second waveguides constitute a second layer of waveguide; The third waveguide layer includes at least two third waveguides arranged in parallel with each other, the third waveguides are arranged perpendicular to the second waveguides, a plurality of second oblique slits are opened on the upper surface of each third waveguide, the third waveguides are respectively connected to the second waveguides through the second oblique slits, and the number of the second oblique slits is the same as the number of the second waveguides; The fourth waveguide layer includes at least one fourth waveguide, wherein a plurality of third oblique slits are formed on an upper surface of the fourth waveguide, and the fourth waveguide is respectively connected to the third waveguides through the third oblique slits, and the number of the third oblique slits is the same as the number of the third waveguides; The vertical polarization waveguide power synthesis network comprises four regions, which respectively correspond to the four regions in the vertical polarization waveguide port radiation array; The vertically polarized waveguide power synthesis network comprises a three-layer waveguide structure; The first layer of waveguides includes a plurality of fifth waveguides arranged in parallel with each other, a fifth waveguide in the middle is shared by four quadrants, each fifth waveguide is respectively connected to a corresponding second waveguide port antenna, and a 90-degree bending structure is adopted at the end of the fifth waveguide to realize connection with the lower layer waveguide, and a plurality of coupling oblique slits are opened on the upper surface of each fifth waveguide, and the number of the coupling oblique slits is the same as the number of the second waveguide port antennas; A sixth waveguide parallel to the fifth waveguide is connected to the 90-degree bending structure at the end of the fifth waveguide, and all the sixth waveguides constitute a second layer of waveguides; The third layer of waveguide includes at least one seventh waveguide, which is perpendicular to the sixth waveguide. The upper surface of the seventh waveguide is provided with a feeding slit, and is connected to the sixth waveguide through the feeding slit. The number of the feeding slits is the same as the number of the sixth waveguide.

2. The dual-polarization monopulse waveguide slot antenna array according to claim 1, characterized in that: The current distribution of the first waveguide antenna adopts Taylor distribution. The first waveguide antenna is turned up at the bottom to form a first waveguide turned-up structure. A metal spacer is arranged in the first waveguide antenna for impedance matching.

3. The dual-polarization monopulse waveguide slot antenna array according to claim 2, characterized in that: The current distribution of the second waveguide mouth antenna adopts Taylor distribution, and the second waveguide mouth antenna has a second waveguide flange structure.

4. The dual-polarization monopulse waveguide slot antenna array according to claim 3, characterized in that: Normalized resistance of all slits r jk and the tilt angle θ jk for: Where P jk is the radiation power of the Kth inclined slot on the jth waveguide, β = 2π / λ g , λ is the free space wavelength, λg is the waveguide wavelength, a and b are the width and height of the waveguide, I jk is the current distribution of the Kth inclined slot on the jth waveguide, obtained by -30dB Taylor distribution.

5. The dual-polarization monopulse waveguide slot antenna array according to claim 4, characterized in that: The normalized resistance of the slanted slits on the first waveguide and the fifth waveguide satisfies:

6. The dual-polarization monopulse waveguide slot antenna array according to claim 5, characterized in that: The horizontal polarization sum and difference network comprises four waveguide magic Ts, which respectively output sum signals, E-plane difference signals and H-plane difference signals of four regions of the horizontal polarization waveguide power synthesis network.

7. The dual-polarized monopulse waveguide slot antenna array according to claim 6, characterized in that: The vertical polarization sum and difference network includes four waveguide magic Ts, which respectively output the sum signal, E-plane difference signal and H-plane difference signal of the four regions of the vertical polarization waveguide power synthesis network, and use an adjustment block to adjust the impedance matching.

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