Low profile dual-band dual-circularly polarized co-feed antenna and array thereof

Abstract

The application provides a low-profile dual-frequency dual-circularly-polarized shared-aperture antenna and an array thereof, and relates to the technical field of antennas.In the application, the shared-aperture antenna adopts a substrate integrated waveguide structure, and a dual-feed-point multimode resonant cavity is a core structure of the substrate integrated waveguide structure.Based on the resonant cavity structure, the traditional complex power-division feed network is simplified.A low-frequency coaxial adapter and a high-frequency coaxial adapter are arranged at the bottom of the dual-feed-point multimode resonant cavity;low-frequency tuning columns and high-frequency tuning columns are regularly arranged in the middle of the dual-feed-point multimode resonant cavity, and are used for adjusting the field distribution characteristics in the resonant cavity;low-frequency radiation slots and high-frequency radiation slots are regularly arranged at the top of the dual-feed-point multimode resonant cavity.In addition, a polarization conversion layer is loaded above the radiation slots, the polarization conversion layer comprises low-frequency polarization conversion metal sheets and high-frequency polarization conversion metal sheets, and the two kinds of polarization conversion metal sheets are regularly distributed on the two sides of the corresponding low-frequency radiation slots or high-frequency radiation slots, so that electromagnetic waves are converted from linear polarization to circular polarization.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, specifically to a low-profile dual-frequency dual-circular polarization common-aperture antenna and its array. Background Technology

[0002] Due to the increasing complexity of wireless systems, a single antenna is often insufficient to meet communication requirements. In most applications, multiple antennas need to be installed within limited space, leading to the concept of common-aperture antennas. A common-aperture antenna consists of multiple antennas that share the same aperture, significantly saving space compared to placing multiple antennas individually. It's important to note that "multiple antennas" here refers to multiple antennas with different structural forms, not identical antenna elements in a traditional antenna array. Current development trends for common-aperture antennas include miniaturization, multi-polarization, and broadband. Miniaturization, such as reducing antenna size and profile, effectively improves the utilization of limited space in communication systems, which is of significant practical importance. Furthermore, the application of multiple polarization methods can further increase the communication capacity of the antenna system.

[0003] Professor Zhong Shunshi's team at Shanghai University was among the first in China and abroad to conduct research on co-aperture antennas. In their paper "Shared Aperture S / X Dual-Band Dual-Polarized Microstrip Antenna Array, Journal of Radio Science, 2008-04-15," they published a dual-band co-aperture antenna with an odd frequency ratio. This antenna uses an orthogonal microstrip dipole antenna in the S-band and a dual-polarized square microstrip patch antenna in the X-band. To achieve a wider bandwidth, both antennas employ a double-layer structure. For feeding, the S-band uses adjacent coupling feeding, while the X-band uses coaxial probe and aperture coupling feeding. Furthermore, in their paper "Ku / Ka Dual-Band Co-aperture Microstrip Array Antenna Design, China Space Science and Technology, 2012-10-25," they implemented a compact Ku / Ka dual-band co-aperture microstrip array antenna design by nesting the dual-band antennas in a coplanar configuration.

[0004] However, the aforementioned multi-frequency, multi-polarization, common-aperture antennas have complex structures, mostly employing intricate microstrip or waveguide power divider networks, or utilizing numerous coaxial converters and RF cables to achieve the arraying of unit structures. This significantly increases the design and manufacturing costs of the antennas and is detrimental to antenna miniaturization and low profile implementation. Summary of the Invention

[0005] (a) Technical problems to be solved

[0006] To address the shortcomings of existing technologies, this invention provides a low-profile dual-frequency dual-circular polarization common-aperture antenna and its array, solving the technical problem of complex feeding structures for multi-frequency, multi-polarization, and common-aperture antennas.

[0007] (II) Technical Solution

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] A low-profile dual-frequency dual-circular polarization common-aperture antenna employs a substrate integrated waveguide structure. The antenna has a dual-feed multimode resonator and a polarization conversion layer stacked from bottom to top. The dual-feed multimode resonator includes a bottom, middle and top of the multimode resonator.

[0010] At the bottom of the multimode resonant cavity, a first metal isolation hole and a second metal isolation hole are provided on the metal back plate. On the downward side of the metal back plate, there are high-frequency coaxial shells corresponding to the first metal isolation hole and low-frequency coaxial shells corresponding to the second metal isolation hole. The high-frequency coaxial inner core passes through the high-frequency coaxial shell and the first metal isolation hole in sequence and extends into the middle of the multimode resonant cavity. The low-frequency coaxial inner core passes through the low-frequency coaxial shell and the second metal isolation hole in sequence and extends into the middle of the multimode resonant cavity.

[0011] In the middle of the multimode resonant cavity, metal shielding holes are provided at intervals along the edge of the first dielectric plate, and several low-frequency metal tuning pillars and high-frequency metal tuning pillars are regularly arranged in the area enclosed by the metal shielding holes.

[0012] At the top of the multimode resonant cavity, the metal top cover plate is provided with low-frequency radiation slots corresponding to the low-frequency metal tuning pillars and high-frequency radiation slots corresponding to the high-frequency metal tuning pillars.

[0013] In the polarization conversion layer, the second dielectric plate is provided with low-frequency polarization conversion metal sheets distributed on both sides of the low-frequency radiation slot, and high-frequency polarization conversion metal sheets distributed on both sides of the high-frequency radiation slot.

[0014] Preferably, the low-profile dual-frequency dual-circular polarized common-aperture antenna has a square aperture overall, and the frequency ratio of the low-frequency antenna to the high-frequency antenna is 1:1.5.

[0015] Preferably, the low-frequency radiation slits are in a 2×2 array, and the high-frequency radiation slits are in a 3×3 array.

[0016] Preferably, the gaps between the low-frequency radiation slits are equal in two mutually perpendicular arrangement directions.

[0017] Preferably, the gaps between the high-frequency radiation slits are equal in two mutually perpendicular arrangement directions.

[0018] Preferably, the low-frequency polarization conversion metal sheet and / or the high-frequency polarization conversion metal sheet are formed by chamfering the corners on both sides of a rectangular metal sheet.

[0019] Preferably, the high-frequency antenna is left-hand circularly polarized, and the low-frequency antenna is right-hand circularly polarized;

[0020] Alternatively, the high-frequency antenna may be right-hand circularly polarized, and the low-frequency antenna may be left-hand circularly polarized;

[0021] Or, the high-frequency antenna and the low-frequency antenna may be circularly polarized with the same rotation direction.

[0022] A low-profile dual-frequency dual-circular polarization common-aperture antenna array includes several low-profile dual-frequency dual-circular polarization common-aperture antennas as described above, with each antenna arranged in a rectangular grid.

[0023] Preferably, the rectangular grid array has a size of 8×8.

[0024] Preferably, the low-profile dual-frequency dual-circular polarization common-aperture antenna array is manufactured using printed circuit board processing technology and is integrally formed.

[0025] (III) Beneficial Effects

[0026] This invention provides a low-profile dual-frequency dual-circularly polarized common-aperture antenna and its array. Compared with the prior art, it has the following advantages:

[0027] In this invention, the common-aperture antenna employs a substrate integrated waveguide structure, the core of which is a dual-feed multimode resonant cavity. Based on this resonant cavity structure, the traditional complex power divider feeding network is simplified. Low-frequency and high-frequency coaxial adapters are located at the bottom of the dual-feed multimode resonant cavity; low-frequency and high-frequency tuning pillars are regularly arranged in the middle of the cavity to adjust the field distribution characteristics inside; and low-frequency and high-frequency radiation slots are regularly arranged at the top. Furthermore, a polarization conversion layer is loaded above the radiation slots, containing low-frequency and high-frequency polarization conversion metal sheets, which are regularly distributed on both sides of the corresponding low-frequency or high-frequency radiation slots, enabling the electromagnetic wave to convert from linear polarization to circular polarization. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figures 1(a) to (c) are a perspective view, a top view, and a front view of a low-profile dual-frequency dual-circular polarization common-aperture antenna provided in an embodiment of the present invention, respectively.

[0030] Figure 2 An exploded view of a low-profile dual-frequency dual-circularly polarized common-aperture antenna provided in an embodiment of the present invention;

[0031] Figures 3(a) to (c) are a perspective view, a top view, and a front view of the bottom of a multimode resonant cavity provided in an embodiment of the present invention, respectively.

[0032] Figures 4(a) to (c) are a perspective view, a top view, and a front view of the middle part of a multimode resonant cavity provided in an embodiment of the present invention, respectively.

[0033] Figures 5(a) to (c) are a perspective view, a top view, and a front view of the top of a multimode resonant cavity provided in an embodiment of the present invention, respectively.

[0034] Figures 6(a) to (c) are a perspective view, a top view, and a front view of a polarization conversion layer provided in an embodiment of the present invention, respectively.

[0035] Figure 7 This is a schematic diagram illustrating the principle of converting antenna centerline polarization into circular polarization according to an embodiment of the present invention;

[0036] Figures 8-9 These are schematic diagrams of the electric field distribution under low-frequency and high-frequency excitation of a dual-feed multimode resonant cavity according to an embodiment of the present invention.

[0037] Figure 10 This is a schematic diagram of a low-profile dual-frequency dual-circular polarization common-aperture antenna array provided in an embodiment of the present invention. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] This application provides a low-profile dual-frequency dual-circular polarization common-aperture antenna and its array, which solves the technical problem of complex feeding structure of multi-frequency, multi-polarization, common-aperture antennas, significantly reduces the design and manufacturing cost of the antenna, and is conducive to the miniaturization and low profile of the antenna.

[0040] The technical solution in this application is to solve the above-mentioned technical problems, and the general idea is as follows:

[0041] This invention provides a low-profile dual-frequency dual-circular polarization common-aperture antenna and its array based on a simplified feeding network. The common-aperture antenna employs a substrate integrated waveguide structure, with its core structure being a dual-feed multimode resonator. Based on this resonator structure, the traditional complex power divider feeding network is simplified. Low-frequency and high-frequency coaxial adapters are disposed at the bottom of the dual-feed multimode resonator; low-frequency and high-frequency tuning pillars are regularly arranged in the middle of the dual-feed multimode resonator to adjust the field distribution characteristics inside the resonator; and low-frequency and high-frequency radiation slots are regularly arranged at the top of the dual-feed multimode resonator. Furthermore, a polarization conversion layer is loaded above the radiation slots, containing low-frequency and high-frequency polarization conversion metal sheets, which are regularly distributed on both sides of the corresponding low-frequency or high-frequency radiation slots, enabling the electromagnetic waves to convert from linear polarization to circular polarization.

[0042] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0043] Example 1:

[0044] As shown in Figures 1(a)~(c), Figure 2 As shown, this embodiment of the invention provides a low-profile dual-frequency dual-circular polarization common-aperture antenna, which adopts a substrate integrated waveguide structure. The antenna has a dual-feed multimode resonator and a polarization conversion layer 4 stacked from bottom to top. The dual-feed multimode resonator includes a bottom 1, a middle 2 and a top 3 of the multimode resonator.

[0045] As shown in Figures 3(a) to (c), at the bottom 1 of the multimode resonant cavity, a first metal isolation hole 102 and a second metal isolation hole 103 are provided on the metal back plate 101. The metal back plate 101 has a high-frequency coaxial shell 106 corresponding to the first metal isolation hole 102 and a low-frequency coaxial shell 107 corresponding to the second metal isolation hole 103 on the downward side. The high-frequency coaxial inner core 104 passes through the high-frequency coaxial shell 106 and the first metal isolation hole 102 in sequence and extends into the middle part 2 of the multimode resonant cavity. The low-frequency coaxial inner core 105 passes through the low-frequency coaxial shell 107 and the second metal isolation hole 103 in sequence and extends into the middle part 2 of the multimode resonant cavity.

[0046] As shown in Figures 4(a) to (c), in the middle part 2 of the multimode resonant cavity, metal shielding holes 202 are provided at intervals along the edge of the first dielectric plate 201. Several low-frequency metal tuning pillars 203 and high-frequency metal tuning pillars 204 are regularly arranged in the rectangular area enclosed by the metal shielding holes 202 to adjust the field distribution characteristics inside the resonant cavity.

[0047] As shown in Figures 5(a) to (c), at the top 3 of the multimode resonant cavity, the metal upper cover plate 301 is provided with a low-frequency radiation slot 302 corresponding to the low-frequency metal tuning column 203, and the two are adjacent to each other in position; and the metal upper cover plate 301 is provided with a high-frequency radiation slot 303 corresponding to the high-frequency metal tuning column 204, and the two are also adjacent to each other in position.

[0048] As shown in Figures 6(a) to (c), in the polarization conversion layer 4, the second dielectric plate 401 is provided with low-frequency polarization conversion metal sheets 403 distributed on both sides of the low-frequency radiation slot 302, and high-frequency polarization conversion metal sheets 402 distributed on both sides of the high-frequency radiation slot 303.

[0049] It is easy to understand that the low frequency and high frequency mentioned in the above scheme are a set of relative concepts and do not involve specific frequency values. Those skilled in the art can choose according to actual needs.

[0050] In an optional embodiment, the aforementioned low-frequency and high-frequency polarization conversion metal sheet is formed by chamfering the corners on both sides of a rectangular metal sheet, and the position and size of the chamfered corners affect the polarization characteristics. For example... Figure 7 As shown, when the chamfer reaches a certain size, the linearly polarized electromagnetic wave emanating from the radiation slit will be decomposed into a pair of orthogonal modes when passing through a pair of polarization conversion metal plates. When the amplitudes of these two modes are equal and their phases differ by 90°, circular polarization can be achieved. For the high-frequency and low-frequency polarization conversion metal plates described in this embodiment, their chamfer positions are different, which will form two types of circular polarization with different directions of rotation.

[0051] Specifically, for high frequencies, when a high-frequency linearly polarized wave radiates from a high-frequency radiation slit, it is decomposed into high-frequency linearly polarized component 1 and high-frequency linearly polarized component 2. These two components are orthogonal, of equal amplitude, and have a 90° phase difference (high-frequency linearly polarized component 1 leads high-frequency linearly polarized component 2), thus producing left-handed circularly polarized radiation. For low frequencies, when a low-frequency linearly polarized wave radiates from a low-frequency radiation slit, it is decomposed into low-frequency linearly polarized component 1 and low-frequency linearly polarized component 2. These two components are orthogonal, of equal amplitude, and have a 90° phase difference (low-frequency linearly polarized component 1 lags high-frequency linearly polarized component 2), thus producing right-handed circularly polarized radiation.

[0052] In an optional embodiment, the low-profile dual-frequency dual-circularly polarized common-aperture antenna has an overall square aperture, and the frequency ratio of the low-frequency antenna to the high-frequency antenna is 1:1.5. Furthermore, the slot element spacing of the low-frequency radiation slot 302 is equal in two mutually perpendicular arrangement directions, and the slot element spacing of the high-frequency radiation slot 303 is also equal in two mutually perpendicular arrangement directions. That is, the slot element spacing of the low-frequency antenna is equal in two mutually perpendicular arrangement directions, and the slot element spacing of the high-frequency antenna is also equal in two mutually perpendicular arrangement directions.

[0053] To satisfy the above requirements for square aperture and frequency ratio, the following two equations must hold:

[0054]

[0055]

[0056] in, and These represent low-frequency and high-frequency frequencies, respectively. and Let represent the relative permittivity and relative permeability of the square first dielectric plate (201), respectively; Let represent the side length of the first square medium plate (201).

[0057] In an optional embodiment, the low-frequency radiation slot 302 is a 2×2 array, and the high-frequency radiation slot 303 is a 3×3 array. That is, the low-frequency antenna is a 2×2 slot array, and the high-frequency antenna is a 3×3 slot array. Of course, the size of the antenna array can be flexibly adjusted and is not limited to this setting.

[0058] In one optional embodiment, the high-frequency antenna is left-handed circularly polarized, and the low-frequency antenna is right-handed circularly polarized. Alternatively, the high-frequency antenna can be right-handed circularly polarized, and the low-frequency antenna can be left-handed circularly polarized. Furthermore, the high-frequency and low-frequency antennas can be designed with the same direction of circular polarization.

[0059] When the antenna operates at low frequency, electromagnetic signals enter the multimode resonant cavity through the low-frequency coaxial core 105, generating signals such as... Figure 7 The electric field distribution is shown. Subsequently, through the adjustment of the low-frequency metal tuning column 203, electromagnetic waves can be radiated from the low-frequency radiation slot 302 at the top 3 of the multimode resonant cavity, and then converted from linear polarization to circular polarization through the low-frequency polarization conversion metal sheet 403 of the polarization conversion layer 4.

[0060] Similarly, when the antenna operates at high frequency, electromagnetic signals enter the multimode resonant cavity 2 from the high-frequency coaxial core 104, generating signals such as... Figure 8 The electric field distribution is shown. Then, through the adjustment of the high-frequency metal tuning column 204, electromagnetic waves can radiate from the high-frequency radiation slot 303 at the top of the multimode resonant cavity 3, and pass through the high-frequency polarization conversion metal sheet 402 of the polarization conversion layer 4 to achieve a conversion from linear polarization to circular polarization.

[0061] like Figure 8The diagram shows the electric field distribution during low-frequency excitation of the dual-feed multimode resonator according to an embodiment of the present invention (taking the excitation field distribution at 20 GHz as an example). The low-frequency radiation slots 302 are distributed at the center of each standing wave, and the amplitude and phase of the electric field are adjusted by the low-frequency metal tuning column 203, ultimately achieving equal-amplitude and in-phase excitation of each low-frequency radiation slot 302.

[0062] like Figure 9 The diagram shows the electric field distribution during high-frequency excitation of the dual-feed multimode resonator according to an embodiment of the present invention (taking the excitation field distribution at 30 GHz as an example). The high-frequency radiation slots 303 are distributed at the center of each standing wave, and the amplitude and phase of the electric field are adjusted by the high-frequency metal tuning pillars 204, ultimately achieving equal-amplitude and in-phase excitation of each high-frequency radiation slot 303.

[0063] Furthermore, although the low-profile dual-frequency dual-circularly polarized common-aperture antenna provided in the embodiments of the present invention adopts a substrate integrated waveguide form, it can actually be replaced with a conventional metal waveguide structure based on the same design principle, which will not be elaborated here.

[0064] Example 2:

[0065] Using the low-profile dual-frequency dual-circularly polarized common-aperture antenna provided in Example 1 as an independent unit, antenna arrays of different sizes can be further constructed.

[0066] like Figure 10 As shown, Embodiment 2 provides a low-profile dual-frequency dual-circular polarization common-aperture antenna array, including several low-profile dual-frequency dual-circular polarization common-aperture antennas as described in Embodiment 1, with each antenna arranged in a rectangular grid, the rectangular grid array having a size of 8×8.

[0067] In an optional embodiment, the low-profile dual-frequency dual-circular polarization common-aperture antenna array is integrally formed based on printed circuit board manufacturing technology, rather than processing and splicing the elements separately. This approach ensures manufacturing accuracy and reduces manufacturing costs.

[0068] It should be noted that specific size parameters are not given in Embodiments 1 and 2 of the present invention, because they can be flexibly designed to meet different operating frequency bands and performance requirements, and no absolute limitation is made here.

[0069] In summary, compared with existing technologies, it has the following beneficial effects:

[0070] 1. The antenna described in this invention uses a simple multimode resonant cavity to replace the complex power divider feed network in traditional multi-frequency, multi-polarization, common-aperture antennas, which reduces the design and manufacturing costs of the antenna to a certain extent.

[0071] 2. The antenna described in this invention comprises only two layers of dielectric substrate structure, with a low cross-sectional height, making it convenient for application in limited spaces;

[0072] 3. The size of the antenna array described in this invention can be flexibly adjusted and is not limited to the 2×2 and 3×3 slot array sizes described in the embodiments;

[0073] 4. The antenna described in this invention has a flat structure, which is extremely convenient for array applications;

[0074] 5. The antenna described in this invention is manufactured using printed circuit board technology, which is a mature process with high reliability, wide application range, and low cost.

[0075] 6. Based on printed circuit board (PCB) manufacturing technology, the large-scale antenna array can be manufactured as a single unit, rather than processing and splicing individual units. This approach ensures manufacturing accuracy and reduces manufacturing costs.

[0076] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0077] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-profile dual-frequency dual-circularly polarized common-aperture antenna, characterized in that, The antenna adopts a substrate integrated waveguide structure and has a dual-feed multimode resonator and a polarization conversion layer stacked from bottom to top (4). The dual-feed multimode resonator includes a bottom (1), a middle (2) and a top (3) of the multimode resonator. At the bottom (1) of the multimode resonant cavity, a first metal isolation hole (102) and a second metal isolation hole (103) are provided on a metal back plate (101). The metal back plate (101) is provided with a high-frequency coaxial shell (106) corresponding to the first metal isolation hole (102) and a low-frequency coaxial shell (107) corresponding to the second metal isolation hole (103) on the downward side. The high-frequency coaxial inner core (104) passes through the high-frequency coaxial shell (106) and the first metal isolation hole (102) in sequence and extends into the middle part (2) of the multimode resonant cavity. The low-frequency coaxial inner core (105) passes through the low-frequency coaxial shell (107) and the second metal isolation hole (103) in sequence and extends into the middle part (2) of the multimode resonant cavity. In the middle part (2) of the multimode resonant cavity, metal shielding holes (202) are provided at intervals along the edge of the first dielectric plate (201), and several low-frequency metal tuning pillars (203) and high-frequency metal tuning pillars (204) are regularly arranged in the area enclosed by the metal shielding holes (202); At the top of the multimode resonant cavity (3), the metal upper cover plate (301) is provided with a low-frequency radiation slot (302) corresponding to the low-frequency metal tuning column (203) and a high-frequency radiation slot (303) corresponding to the high-frequency metal tuning column (204). In the polarization conversion layer (4), the second dielectric plate (401) is provided with low-frequency polarization conversion metal sheets (403) distributed on both sides of the low-frequency radiation slot (302) and high-frequency polarization conversion metal sheets (402) distributed on both sides of the high-frequency radiation slot (303). The low-frequency polarization conversion metal sheet (403) and the high-frequency polarization conversion metal sheet (402) are formed by chamfering the two sides of a rectangular metal sheet.

2. The low-profile dual-frequency dual-circularly polarized common-aperture antenna as described in claim 1, characterized in that, The low-profile dual-frequency dual-circular polarized common-aperture antenna has a square aperture overall, and the frequency ratio of the low-frequency antenna to the high-frequency antenna is 1:1.

5.

3. The low-profile dual-frequency dual-circularly polarized common-aperture antenna as described in claim 2, characterized in that, The low-frequency radiation slit (302) is a 2×2 array, and the high-frequency radiation slit (303) is a 3×3 array.

4. The low-profile dual-frequency dual-circularly polarized common-aperture antenna as described in claim 1, characterized in that, The low-frequency radiation slit (302) has equal spacing between its slit units in two mutually perpendicular arrangement directions, and / or the high-frequency radiation slit (303) has equal spacing between its slit units in two mutually perpendicular arrangement directions.

5. The low-profile dual-frequency dual-circularly polarized common-aperture antenna as described in any one of claims 1 to 4, characterized in that, The high-frequency antenna is left-hand circularly polarized, and the low-frequency antenna is right-hand circularly polarized; Alternatively, the high-frequency antenna may be right-hand circularly polarized, and the low-frequency antenna may be left-hand circularly polarized; Or, the high-frequency antenna and the low-frequency antenna may be circularly polarized with the same rotation direction.

6. A low-profile dual-frequency dual-circular polarization common-aperture antenna array, characterized in that, It includes several low-profile dual-frequency dual-circularly polarized common-aperture antennas as described in any one of claims 1 to 5, wherein the antennas are arranged in a rectangular grid.

7. The low-profile dual-frequency dual-circular polarization common-aperture antenna array as described in claim 6, characterized in that, The rectangular grid array has a size of 8×8.

8. The low-profile dual-frequency dual-circular polarization common-aperture antenna array as described in claim 6 or 7, characterized in that, Based on printed circuit board processing technology, the low-profile dual-frequency dual-circular polarization common-aperture antenna array is integrally processed and formed.

Images