A SIW cross-band dual circular polarization fusion antenna compatible with microwave and millimeter waves

Abstract

The present invention provides a microwave and millimeter wave compatible SIW cross-band dual circularly polarized fusion antenna, comprising an upper metal layer, a first dielectric layer, an intermediate metal layer, a second dielectric layer, a floor metal layer, a third dielectric layer, and a feed network layer, which are stacked in sequence from top to bottom; four groups of first metal through-hole arrays are provided on the first dielectric layer, each group of first metal through-hole arrays correspondingly provided below a square radiating unit; the upper and lower ends of the first metal through-hole arrays are electrically connected to the square radiating unit and the intermediate metal layer, respectively, to form a millimeter wave radiating SIW structure; the second dielectric layer is provided with a second metal through-hole array, the upper and lower ends of the second metal through-hole array are electrically connected to the intermediate metal layer and the floor metal layer, respectively, to reuse the intermediate metal layer to form a microwave radiating SIW structure. While maintaining good circular polarization characteristics, the present invention can achieve a cross-band dual-frequency operating mode in the millimeter wave band and the microwave band.

Description

Technical Field

[0001] The present invention relates to the field of communication antennas, and in particular to a SIW cross-band dual circular polarization fusion antenna compatible with microwave and millimeter waves. Background Art

[0002] Satellite mobile communications technology, with its advantages of wide coverage and insensitivity to ground conditions, has become a key research area in terrestrial mobile communications. Mobile receiving antennas for satellite communications require circular polarization to adapt to the high-speed motion of satellites and avoid polarization mismatch. Furthermore, due to the diverse operating frequency bands of various satellite communications, dual-band or wideband antennas are also crucial features required for mobile receiving antennas. Microwave and millimeter-wave bands have been particularly hot spots for satellite communications development in recent years.

[0003] Therefore, it is necessary to design a circularly polarized antenna that can work in both microwave and millimeter wave bands. Some antennas in the prior art have some defects to a greater or lesser extent and cannot meet the above design requirements.

[0004] For example, the Chinese invention patent application with publication number CN114614260A discloses a broadband circularly polarized microstrip antenna with a bottom slot and a satellite communication terminal. The antenna achieves broadband function through the slots in the floor, but it is a single-band antenna with a low operating frequency, and the resonant frequency is only 4.5 GHz.

[0005] Another example is the Chinese invention patent with application publication number CN111355025A, which discloses a dual-frequency circularly polarized antenna structure. The antenna unit consists of two spiral antenna structures and has dual-frequency circular polarization function, but the operating frequency is relatively low, at 2.4 GHz and 5 GHz, which cannot meet the communication requirements of the microwave and millimeter wave bands. Summary of the Invention

[0006] The purpose of the present invention is to address the defects in the prior art and provide a SIW cross-band dual-circular polarization fusion antenna compatible with microwave and millimeter waves, so that the antenna can achieve a cross-band dual-frequency working mode in the millimeter wave band and the microwave band while maintaining good circular polarization characteristics.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A microwave and millimeter wave compatible SIW cross-band dual circular polarization fusion antenna, comprising an upper metal layer, a first dielectric layer, an intermediate metal layer, a second dielectric layer, a floor metal layer, a third dielectric layer, and a feed network layer stacked in sequence from top to bottom;

[0009] The upper metal layer includes four square radiation units of the same shape printed on the upper surface of the first dielectric layer; the four square radiation units are arranged in a matrix of two rows and two columns on the first dielectric layer;

[0010] The feed network layer includes a microwave feed network and a millimeter wave feed network printed on the lower surface of the third dielectric plate;

[0011] The microwave feeding network has an input end and four output ends, and the four output ends of the microwave feeding network are respectively fed to the intermediate metal layer through a microwave feeding probe; the lower end of the microwave feeding probe is electrically connected to the output end of the microwave feeding network, and the upper end of the microwave feeding probe passes through the third dielectric layer, the floor metal layer, and the second dielectric layer in sequence, and is electrically connected to the intermediate metal layer;

[0012] The millimeter-wave feeding network has an input end and four output ends. The four output ends of the millimeter-wave feeding network correspond one-to-one to the four square radiating elements on the upper metal layer. Each output end of the millimeter-wave feeding network feeds power to one square radiating element through a millimeter-wave feeding probe. The lower end of the millimeter-wave feeding probe is electrically connected to the output end of the millimeter-wave feeding network. The upper end of the millimeter-wave feeding probe passes through the third dielectric layer, the floor metal layer, the second dielectric layer, the middle metal layer, and the first dielectric layer in sequence, and is electrically connected to the center of the square radiating element.

[0013] Four groups of first metal through-hole arrays are provided on the first dielectric layer, each group of the first metal through-hole arrays is correspondingly provided below a square radiating unit; the upper and lower ends of the first metal through-hole arrays are electrically connected to the square radiating unit and the middle metal layer respectively, to form a millimeter wave radiation SIW structure;

[0014] A second metal through-hole array is provided on the second dielectric layer. The upper and lower ends of the second metal through-hole array are electrically connected to the middle metal layer and the floor metal layer respectively, so as to reuse the middle metal layer and form a microwave radiation SIW structure.

[0015] Furthermore, each group of the first metal through-hole arrays includes a plurality of type A metal through-holes, and the plurality of type A metal through-holes are arranged on the first dielectric layer along the edges and center line of the coverage area of ​​the square radiation unit.

[0016] Furthermore, the middle metal layer is square, the second metal through-hole array includes a plurality of type B metal through-holes, and the plurality of type B metal through-holes are cross-arranged along two diagonals of the coverage area of ​​the middle metal layer on the second dielectric layer.

[0017] Furthermore, the first dielectric layer, the second dielectric layer and the third dielectric layer are each provided with four type A non-metallic through holes for millimeter wave feeding probes to pass through;

[0018] The floor metal layer and the intermediate metal layer are each provided with four Class A circular slots for millimeter wave feeding probes to pass through; the diameter of the Class A circular slots is larger than the Class A non-metallic through-holes, so that the millimeter wave feeding probes do not contact the floor metal layer and the intermediate metal layer.

[0019] Furthermore, the third dielectric layer and the second dielectric layer are each provided with four Class B non-metallic through holes for microwave feeding probes to pass through;

[0020] The floor metal layer is provided with four Class B circular slots for microwave feeding probes to pass through; the diameter of the Class B circular slots is larger than the Class B non-metallic through holes, so that the microwave feeding probes and the floor metal layer do not contact each other.

[0021] Furthermore, a group of metal short-circuit column arrays are respectively provided around each Class A non-metallic through-hole on the second dielectric layer, for suppressing the adverse radiation of the millimeter-wave feeding probe to the microwave band antenna; each group of metal short-circuit column arrays includes eight metal short-circuit columns, and the eight metal short-circuit columns are evenly spaced in a circle around the Class A non-metallic through-hole, enclosing the Class A non-metallic through-hole; the upper and lower ends of the metal short-circuit column are electrically connected to the middle metal layer and the floor metal layer respectively.

[0022] Furthermore, the four output ends of the microwave feeding network have a phase difference of 90° in sequence, and the four output ends of the millimeter wave feeding network have a phase difference of 90° in sequence, so as to provide feeding signals with a phase difference of 90° to the four square radiating units.

[0023] Furthermore, each square radiation unit is provided with four mutually parallel rectangular slits, and the length direction of the four rectangular slits is parallel to one of the side edges of the square radiation unit; the four rectangular slits are arranged into a two-row and two-column slit matrix on the square radiation unit, and the slit matrix is ​​eccentrically arranged on the square radiation unit, and the line connecting the center of the slit matrix and the center of the square radiation unit is parallel to the width direction of the rectangular slit.

[0024] Furthermore, the four square radiation units are distributed on the upper surface of the first dielectric layer in a rotationally symmetrical manner in a clockwise direction with the center of the first dielectric layer as the center and a rotation period of 90° as a unit.

[0025] Furthermore, the connection points of the four microwave feeding probes and the intermediate metal layer are respectively located on the lines connecting the center of the intermediate metal layer and the midpoints of the four side edges, and the distances from the four connection points to the center of the intermediate metal layer are the same to form a HMSIW radiation structure.

[0026] Compared with the prior art, the present invention has the following technical effects:

[0027] 1. The present invention integrates two SIW structures operating in different frequency bands into a composite radiation structure by reusing an intermediate metal layer, so that the antenna can achieve a cross-band dual-frequency operation mode in the millimeter wave band and the microwave band.

[0028] 2. The present invention sequentially changes the feed phase of each square radiating element with a 90° phase gradient. This array arrangement enables the antenna to achieve excellent circular polarization in both the millimeter-wave and microwave bands. Furthermore, the present invention incorporates rectangular slots offset from the centerline within the square radiating elements. By properly sizing and offsetting the slots, the antenna gain can be increased, achieving a good matching bandwidth.

[0029] 3. The present invention also arranges a metal short-circuit column array around the millimeter wave feeding probe, which greatly improves the isolation of the antenna when working in the millimeter wave band and the microwave band. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is an exploded diagram of a microwave and millimeter wave compatible SIW cross-band dual circular polarization fusion antenna provided by an embodiment of the present invention.

[0031] Figure 2 3 is a top view of the structure of the upper metal layer in an embodiment of the present invention.

[0032] Figure 3 3 is a top view of the structure of the first dielectric layer in an embodiment of the present invention.

[0033] Figure 4 3 is a top view of the structure of the intermediate metal layer in an embodiment of the present invention.

[0034] Figure 5 4 is a top view of the second dielectric layer in an embodiment of the present invention.

[0035] Figure 6 4 is a top view of the metal floor layer in an embodiment of the present invention.

[0036] Figure 7 4 is a top view of the structure of the third dielectric layer in an embodiment of the present invention.

[0037] Figure 8 4 is a top view of the structure of the feed network layer in an embodiment of the present invention.

[0038] Figure 9 These are the return loss and isolation parameters of the antenna when the embodiment of the present invention operates in the millimeter wave band.

[0039] Figure 10 These are the axial ratio and gain parameters of the antenna when the embodiment of the present invention operates in the millimeter wave band.

[0040] Figure 11 These are the main polarization and cross-polarization patterns of the antenna when the embodiment of the present invention operates in the millimeter wave band.

[0041] Figure 12 These are the return loss and isolation parameters of the antenna when the embodiment of the present invention operates in the microwave band.

[0042] Figure 13 These are the axial ratio and gain parameters of the antenna when the embodiment of the present invention operates in the microwave band.

[0043] Figure 14 These are the main polarization and cross-polarization directional patterns of the antenna when the embodiment of the present invention operates in the microwave band. DETAILED DESCRIPTION

[0044] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0045] like Figures 1 to 8 As shown, an embodiment of the present invention provides a microwave and millimeter wave compatible SIW cross-band dual circular polarization fusion antenna, including an upper metal layer 2, a first dielectric layer 11, an intermediate metal layer 3, a second dielectric layer 12, a floor metal layer 4, a third dielectric layer 13 and a feed network layer 5 stacked in sequence from top to bottom.

[0046] The upper metal layer 2 includes four square radiation units 20 of the same shape printed on the upper surface of the first dielectric layer 11. The four square radiation units 20 are arranged in a matrix of two rows and two columns on the first dielectric layer 11.

[0047] The feed network layer 5 includes a microwave feed network 52 and a millimeter wave feed network 51 printed on the lower surface of the third dielectric plate 13;

[0048] The microwave feeding network 52 has an input end 521 and four output ends 522. The four output ends 522 of the microwave feeding network 52 are respectively fed to the intermediate metal layer 3 through a microwave feeding probe 62. The lower end of the microwave feeding probe 62 is electrically connected to the output end 522 of the microwave feeding network 52. The upper end of the microwave feeding probe 62 passes through the third dielectric layer 13, the floor metal layer 4, and the second dielectric layer 12 in sequence, and is electrically connected to the intermediate metal layer 3.

[0049] The millimeter wave feeding network 51 has an input end 511 and four output ends 512. The four output ends 512 of the millimeter wave feeding network 51 correspond one-to-one to the four square radiating elements 20 on the upper metal layer 2. Each output end 512 of the millimeter wave feeding network 51 feeds power to one of the square radiating elements 20 through a millimeter wave feeding probe 61. The lower end of the millimeter wave feeding probe 61 is electrically connected to the output end 512 of the millimeter wave feeding network 51. The upper end of the millimeter wave feeding probe 61 passes through the third dielectric layer 13, the floor metal layer 4, the second dielectric layer 12, the intermediate metal layer 3, and the first dielectric layer 11 in sequence, and is electrically connected to the center of the square radiating element 20.

[0050] Four groups of first metal through-hole arrays 71 are provided on the first dielectric layer 11, each group of first metal through-hole arrays 71 is correspondingly provided below a square radiating element 20; the upper and lower ends of the first metal through-hole arrays 71 are electrically connected to the square radiating element 20 and the intermediate metal layer 3, respectively, to form a millimeter wave radiation SIW structure;

[0051] A second metal through-hole array 72 is provided on the second dielectric layer 12 . The upper and lower ends of the second metal through-hole array 72 are electrically connected to the middle metal layer 3 and the floor metal layer 4 respectively, so as to reuse the middle metal layer 3 and form a microwave radiation SIW structure.

[0052] Based on the above features, the present invention proposes a novel, cross-band, dual-frequency, dual-circularly polarized composite SIW structure. The intermediate metal layer 3 is reused by the SIW structure consisting of the upper metal layer 2 and the first dielectric layer 11, and the SIW structure consisting of the bottom metal layer 4 and the second dielectric layer 12. The upper and lower SIW structures, which reuse the intermediate metal layer 3, operate in the millimeter wave and microwave bands, respectively. This enables the overall antenna structure to achieve cross-band, dual-frequency operation.

[0053] Specifically, if Figure 2 As shown, each square radiating element 20 is provided with four mutually parallel rectangular slots 21, the length direction of the four rectangular slots 21 being parallel to one of the side edges of the square radiating element 20. The four rectangular slots 21 are arranged in a slot matrix of two rows and two columns on the square radiating element 20. The slot matrix is ​​eccentrically disposed on the square radiating element 20, and the line connecting the center of the slot matrix and the center of the square radiating element 20 is parallel to the width direction of the rectangular slot 21. That is, the center of the slot matrix does not overlap with the center of the square radiating element 20, and the center of the slot matrix is ​​offset by a distance along the width direction of the rectangular slot 21.

[0054] By adjusting the physical dimensions of the rectangular slots 21, the antenna's resonance point can be adjusted, facilitating better impedance matching and thus a wider operating bandwidth. By also adjusting the offset of the rectangular slots 21 relative to the center of the square radiating element 20, the antenna's gain in the millimeter wave band can be effectively improved. In this embodiment, the side length of the square radiating element 20 is 18.4 mm, the length of the rectangular slots 21 is 5.6 mm, the width of the rectangular slots 21 is 2 mm, and the distance between the center of the slot matrix and the center of the square radiating element 20 is 1.5 mm.

[0055] Furthermore, the four square radiating elements 20 are symmetrically distributed in a clockwise direction on the upper surface of the first dielectric layer, centered at the center of the first dielectric layer 11 and rotating symmetrically with a period of 90 degrees. The above spatial distribution relationship is specifically manifested in that the distribution orientations of the slot matrices on the four square radiating elements 20 are different. Specifically, between two clockwise adjacent square radiating elements 20, the slot matrix distribution pattern on the next square radiating element 20 can be obtained by rotating the slot matrix distribution pattern on the previous square radiating element 20 90 degrees clockwise.

[0056] like Figure 3 As shown, on the first dielectric layer 11 , each group of first metal through-hole arrays 71 includes a plurality of Class A metal through-holes, which are arranged along the edge and center line of the coverage area of ​​the square radiation unit 20 on the first dielectric layer 11 .

[0057] like Figure 4 and Figure 5 As shown, the middle metal layer 3 is square. In the second dielectric layer 12, the second metal via array 72 includes a plurality of type B metal vias, which are arranged crosswise along two diagonal lines of the coverage area of ​​the middle metal layer 3 on the second dielectric layer 12.

[0058] Combine Figures 3 to 7 As shown, the first dielectric layer 11, the second dielectric layer 12 and the third dielectric layer 13 are each provided with four type A non-metallic through holes 81 for the millimeter wave feeding probe 61 to pass through;

[0059] The floor metal layer 4 and the intermediate metal layer 3 are each provided with four Class A circular slots 82 for the millimeter wave feeding probe 61 to pass through; the diameter of the Class A circular slots 82 is larger than the Class A non-metallic through-holes 81, so that the millimeter wave feeding probe 61 does not contact the floor metal layer 4 and the intermediate metal layer 3.

[0060] Furthermore, the third dielectric layer 13 and the second dielectric layer 12 are each provided with four B-type non-metallic through holes 83 for the microwave feeding probe 62 to pass through;

[0061] The floor metal layer 4 is provided with four Class B circular slots 84 for the microwave feeding probe 62 to pass through; the diameter of the Class B circular slots 84 is larger than the Class B non-metallic through-holes 83, so that the microwave feeding probe 62 and the floor metal layer 4 do not contact each other.

[0062] like Figure 5 As shown, as an improvement, a group of metal short-circuit column arrays 85 are respectively provided around each Class A non-metallic through hole 81 on the second dielectric layer 12, which is used to suppress the adverse radiation of the millimeter wave feeding probe 61 to the microwave band antenna; each group of metal short-circuit column arrays 85 includes eight metal short-circuit columns, and the eight metal short-circuit columns are evenly spaced in a circle around the Class A non-metallic through hole 81, enclosing the Class A non-metallic through hole 81; the upper and lower ends of the metal short-circuit columns are electrically connected to the intermediate metal layer 3 and the floor metal layer 4 respectively.

[0063] In this embodiment, the eight metal shorting posts are all made of copper. The eight copper shorting posts, evenly distributed around each millimeter-wave feed probe 61, act as signal shields, preventing the millimeter-wave feed probe 61 from adversely affecting the antenna's microwave signals and improving isolation.

[0064] like Figure 8 As shown, the four output ends 522 of the microwave feeding network 52 have a phase difference of 90° in sequence, and the four output ends 512 of the millimeter wave feeding network 51 have a phase difference of 90° in sequence, which are used to provide feeding signals with a phase difference of 90° to the four square radiating elements 20.

[0065] Combine Figures 1 to 8 As shown, the connection points between the four millimeter-wave feeding probes 61 and the four square radiating elements 20 are located at the centers of the four square radiating elements 20. Therefore, the Class A non-metallic through-holes 81 and the Class A circular slots 82 for the millimeter-wave feeding probes 61 to pass through are respectively arranged at corresponding projected positions on the first dielectric layer 11, the second dielectric layer 12, the third dielectric layer 13, the floor metal layer 4, and the intermediate metal layer 3.

[0066] The connection points between the four microwave feed probes 62 and the intermediate metal layer 3 are located on the lines connecting the center of the intermediate metal layer 3 and the midpoints of its four side edges. Each of these connection points is equidistant from the center of the intermediate metal layer 3, forming a HMSIW radiation structure. Therefore, the Class B non-metallic vias 83 and Class B circular slots 84, through which the microwave feed probes 62 pass, are located at corresponding projected locations on the third dielectric layer 13, the second dielectric layer 12, and the floor metal layer 4, respectively.

[0067] The operating principle of this embodiment of the present invention is as follows: When the antenna operates in the microwave frequency band, current transmitted from an external coaxial line enters the microwave feed network 52 through the input terminal 521. After passing through the microwave feed network 52, current sequentially forms a 90° phase difference at the four output terminals 522. Current is then transmitted through a microwave feed probe 62 connected to each output terminal 522 to the microwave-band SIW radiating structure composed of the intermediate metal layer 3, the second dielectric layer 12, and the floor metal layer 4. Similarly, when the antenna operates in the millimeter wave frequency band, current transmitted from an external coaxial line enters the millimeter wave feed network 51 through the input terminal 511. After passing through the millimeter wave feed network 51, current sequentially forms a 90° phase difference at the four output terminals 512. Current is then transmitted through a millimeter wave feed probe 61 connected to each output terminal 512 to the millimeter wave SIW radiating structure composed of the upper metal layer 2, the first dielectric layer 11, and the intermediate metal layer 3.

[0068] The millimeter wave SIW radiation structure and the microwave band SIW radiation structure share the intermediate metal layer 3, so that the antenna structure of the present invention can achieve a dual-frequency working mode in the millimeter wave band and the microwave band.

[0069] On this basis, since the four square radiating elements in the present invention are distributed in a central rotationally symmetrical manner, and the feeding network at the bottom layer provides feeding signals with a 90° phase difference to different radiating elements respectively, this array arrangement enables the antenna to have a very stable circular polarization characteristic when working.

[0070] At the same time, by introducing eight metal short-circuit posts at each of the four Class A non-metallic through holes 81 in the second dielectric layer 12, a high degree of isolation between the millimeter wave band and the microwave band is achieved.

[0071] Furthermore, by adjusting the offset and physical size of the rectangular slots 21 in each square radiating element 20 of the upper metal layer 2 , the gain of the antenna operating in the millimeter wave band and its impedance matching bandwidth can be greatly improved.

[0072] Through the above structure, the present invention provides a SIW cross-band dual circular polarization fusion antenna compatible with microwave and millimeter waves, which can work in the millimeter wave band and microwave band at the same time and has good radiation characteristics.

[0073] like Figure 9 As shown, the relative impedance bandwidth of this embodiment when working in the millimeter wave band is 16.48%, and the antenna isolation is greater than 35dB; Figure 10 As shown in Figure 2, the maximum gain of the antenna in the millimeter wave band reaches 16dB, and the axial ratio bandwidth reaches 12.4%. Figure 11 As shown, when the antenna operates in the millimeter wave band, in the +z-axis direction, the right-hand circular polarization field is more than 17 dB higher than the left-hand circular polarization field, indicating that the antenna of this embodiment has good right-hand circular polarization performance in the millimeter wave band.

[0074] like Figure 12 As shown, the relative impedance bandwidth of this embodiment when working in the microwave band is 2.6%, and the antenna isolation is greater than 45dB; Figure 13 As shown in Figure 2, the antenna has a maximum gain of 8.7 dB in the microwave band and an axial ratio bandwidth of 1%. Figure 14 As shown, when the antenna operates in the microwave band, in the radiation direction of the +z axis, the component of the left-hand circular polarization field is more than 20 dB higher than the right-hand circular polarization field, indicating that the antenna of this embodiment has good left-hand circular polarization performance in the microwave band.

[0075] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A microwave and millimeter wave compatible SIW cross-band dual circular polarization fusion antenna, characterized by: It includes an upper metal layer, a first dielectric layer, an intermediate metal layer, a second dielectric layer, a floor metal layer, a third dielectric layer and a feed network layer stacked in sequence from top to bottom; The upper metal layer includes four square radiation units of the same shape printed on the upper surface of the first dielectric layer; the four square radiation units are arranged in a matrix of two rows and two columns on the first dielectric layer; The feed network layer includes a microwave feed network and a millimeter wave feed network printed on the lower surface of the third dielectric layer; The microwave feeding network has an input end and four output ends, and the four output ends of the microwave feeding network are respectively fed to the intermediate metal layer through a microwave feeding probe; the lower end of the microwave feeding probe is electrically connected to the output end of the microwave feeding network, and the upper end of the microwave feeding probe passes through the third dielectric layer, the floor metal layer, and the second dielectric layer in sequence, and is electrically connected to the intermediate metal layer; The millimeter wave feeding network has an input end and four output ends. The four output ends of the millimeter wave feeding network correspond one-to-one to the four square radiating elements on the upper metal layer. Each output end of the millimeter wave feeding network feeds power to one square radiating element through a millimeter wave feeding probe. The lower end of the millimeter-wave feeding probe is electrically connected to the output end of the millimeter-wave feeding network, and the upper end of the millimeter-wave feeding probe passes through the third dielectric layer, the floor metal layer, the second dielectric layer, the middle metal layer, and the first dielectric layer in sequence, and is electrically connected to the center of the square radiating unit; Four groups of first metal through-hole arrays are provided on the first dielectric layer, each group of the first metal through-hole arrays is correspondingly provided below a square radiating unit; the upper and lower ends of the first metal through-hole arrays are electrically connected to the square radiating unit and the middle metal layer respectively, to form a millimeter wave radiation SIW structure; A second metal through-hole array is provided on the second dielectric layer, and upper and lower ends of the second metal through-hole array are electrically connected to the middle metal layer and the floor metal layer respectively, so as to reuse the middle metal layer to form a microwave radiation SIW structure; Each group of first metal through-hole arrays includes a plurality of type A metal through-holes, and the plurality of type A metal through-holes are arranged on the first dielectric layer along the edge and center line of the square radiation unit coverage area; The middle metal layer is square, and the second metal through-hole array includes a plurality of type B metal through-holes, which are arranged crosswise along two diagonal lines of the coverage area of ​​the middle metal layer on the second dielectric layer.

2. The microwave-millimeter-wave compatible SIW cross-band dual circular polarization fusion antenna according to claim 1, characterized in that: The first dielectric layer, the second dielectric layer and the third dielectric layer are each provided with four type A non-metallic through holes for millimeter wave feeding probes to pass through; The floor metal layer and the intermediate metal layer are each provided with four Class A circular slots for millimeter wave feeding probes to pass through; the diameter of the Class A circular slots is larger than the Class A non-metallic through-holes, so that the millimeter wave feeding probes do not contact the floor metal layer and the intermediate metal layer.

3. The microwave-millimeter-wave compatible SIW cross-band dual circular polarization fusion antenna according to claim 1, characterized in that: The third dielectric layer and the second dielectric layer are each provided with four Class B non-metallic through holes for microwave feeding probes to pass through; The floor metal layer is provided with four Class B circular slots for microwave feeding probes to pass through; the diameter of the Class B circular slots is larger than the Class B non-metallic through holes, so that the microwave feeding probes and the floor metal layer do not contact each other.

4. The microwave-millimeter-wave compatible SIW cross-band dual circular polarization fusion antenna according to claim 2, characterized in that: A group of metal short-circuit column arrays are respectively provided around each Class A non-metallic through-hole on the second dielectric layer, which is used to suppress the adverse radiation of the millimeter-wave feeding probe to the microwave band antenna; each group of metal short-circuit column arrays includes eight metal short-circuit columns, and the eight metal short-circuit columns are evenly spaced in a circle around the Class A non-metallic through-hole, enclosing the Class A non-metallic through-hole; the upper and lower ends of the metal short-circuit column are electrically connected to the middle metal layer and the floor metal layer respectively.

5. The microwave-millimeter-wave compatible SIW cross-band dual circular polarization fusion antenna according to claim 1, characterized in that: The four output ends of the microwave feeding network have a phase difference of 90° in sequence, and the four output ends of the millimeter wave feeding network have a phase difference of 90° in sequence, so as to provide feeding signals with a phase difference of 90° to the four square radiating elements.

6. The microwave-millimeter-wave compatible SIW cross-band dual circular polarization fusion antenna according to claim 1, characterized in that: On each square radiation unit, four mutually parallel rectangular slots are provided, and the length direction of the four rectangular slots is parallel to one of the side edges of the square radiation unit; The four rectangular slots are arranged into a slot matrix of two rows and two columns on the square radiation unit. The slot matrix is ​​eccentrically arranged on the square radiation unit, and the line connecting the center of the slot matrix and the center of the square radiation unit is parallel to the width direction of the rectangular slot.

7. The microwave-millimeter-wave compatible SIW cross-band dual circular polarization fusion antenna according to claim 6, characterized in that: The four square radiation units are symmetrically distributed in a clockwise direction on the upper surface of the first dielectric layer, with the center of the first dielectric layer as the center and a rotation period of 90 degrees as a unit.

8. The microwave-millimeter-wave compatible SIW cross-band dual circular polarization fusion antenna according to claim 1, characterized in that: The connection points of the four microwave feeding probes and the middle metal layer are respectively located on the lines connecting the center of the middle metal layer and the midpoints of the four sides, and the distances from the four connection points to the center of the middle metal layer are the same to form a HMSIW radiation structure.

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