An airborne platform low-profile omnidirectional array antenna based on lens mechanism

Abstract

The application discloses a low profile omnidirectional array antenna based on a lens mechanism, which is characterized in that a circular metal bottom cavity is arranged on a ground plate, a center antenna is arranged in the middle of the metal bottom cavity, and edge antennas are equidistantly and equiangularly distributed in the circumference of the metal bottom cavity and around the outer periphery of the center antenna, wherein the center antenna comprises a center metal cavity and a center antenna unit coaxially arranged in the center metal cavity, each edge metal cavity comprises an edge antenna unit arranged in the edge metal cavity, and the edge antenna unit is inscribed in the edge metal cavity; the antenna unit is embedded in the metal cavity to resist the interference of the external environment on the antenna, and the radiation performance and the anti-interference ability of the antenna are enhanced; the distribution of the dielectric lens unit is used to control the antenna pattern, and the comprehensive performance of the communication and navigation system of the airborne platform is improved by realizing the double resonance and miniaturization of the antenna.

Description

Technical Field

[0001] This invention belongs to the field of airborne antenna technology, specifically relating to a low-profile omnidirectional array antenna for airborne platforms based on lens mechanism. Background Technology

[0002] A direction-finding antenna is an antenna used in space-based direction-finding systems. As a radio device, the antenna is a crucial component of a direction-finding system, directly affecting the overall quality of the radio signal transmission and reception. Airborne electronic direction-finding systems offer advantages such as a large operating range, long detection distance, and the ability to locate targets on a single aircraft. Furthermore, due to the limited size of airborne platforms, they are gradually evolving towards more compact direction-finding arrays.

[0003] Space direction-finding systems are susceptible to interference from other radio signals during the reception of space radio signals; signals outside the target equipment act as noise. When the distance between the radiation source being measured and the direction-finding system is too great, the signal-to-noise ratio (SNR) of the target signal becomes too low, or it may even be completely overwhelmed by noise, causing the direction-finding process to fail. To improve the SNR of the received signal, the gain of the direction-finding antenna can be increased. Increasing the gain of the direction-finding antenna can also effectively increase the effective operating radius of the space direction-finding system, significantly improving its efficiency.

[0004] Similarly, since the technical characteristic parameters of communication signals do not carry their attribute markers, and the information they transmit is difficult to crack under encryption conditions, to achieve rapid search for communication signals in complex radio signal networks, it is necessary to combine it with rapid and accurate direction finding and positioning. However, using two sets of arrays for communication and direction finding is unreasonable in the compact airborne platform environment. Therefore, it is particularly important to achieve an integrated design of communication and direction finding.

[0005] Furthermore, the antenna profile height needs to be considered when designing a direction-finding antenna array; an excessively high profile can negatively impact the aircraft's aerodynamic performance. Typically, large-scale antenna arrays are used, and if mounted on the surface of the carrier, the large windward area and resulting wind resistance can lead to structural instability.

[0006] In summary, the profile height of a typical direction-finding antenna array element is... In the vicinity, the excessively high profile makes it difficult to integrate into the airborne platform, and due to the mutual coupling between array elements, the azimuth gain will be reduced, resulting in a low signal-to-noise ratio of the target signal, or even being directly submerged by noise signals, leading to a serious decrease in direction finding accuracy.

[0007] Patent application CN113131178B discloses a direction-finding antenna, a direction-finding antenna system, and electronic equipment. The direction-finding antenna includes a substrate and an antenna radiating assembly. The substrate has a first surface and a second surface that are opposite to each other. The antenna radiating assembly includes a high-frequency radiating element array and a low-frequency radiating element array. Specifically, the high-frequency radiating element array includes at least one high-frequency radiating element, which includes a first high-frequency radiating arm and a second high-frequency radiating arm symmetrically arranged. The first high-frequency radiating arm is disposed on the first surface, and the second high-frequency radiating arm is disposed on the second surface. A first high-frequency feed line is connected to the first high-frequency radiating arm, and a second high-frequency feed line is connected to the second high-frequency radiating arm. The low-frequency radiating element array includes at least one low-frequency radiating element, which includes a first low-frequency radiating arm and a second low-frequency radiating arm symmetrically arranged. This solution addresses the problems of large size, single frequency band, and insufficient gain in current direction-finding antennas. However, it cannot yet achieve the comprehensive performance of an integrated airborne direction-finding and communication system, and its detection accuracy is insufficient. Summary of the Invention

[0008] To overcome the shortcomings of the existing technology, the present invention aims to propose a low-profile omnidirectional array antenna for airborne platforms based on the lens mechanism, utilizing the TM in the S-band microstrip patch antenna. 01 The mode is used to obtain the desired vertical polarization radiation pattern, and by adjusting the TM... 01 and TM 02 By adjusting the radiation mode, the operating bandwidth of the intracavity antenna can be expanded, achieving a wide bandwidth and providing certain anti-interference, anti-multipath, and anti-Doppler frequency shift capabilities. At the same time, through the low-profile unit setting of the antenna unit cavity, the loading of equivalent dummy element lenses, and the array antenna arrangement, the azimuth and elevation measurements of the incoming wave signal, multi-node network communication, and distance measurement between network members can be achieved, thereby improving the overall performance of the airborne integrated direction finding and communication system.

[0009] To achieve the above objectives, the technical means employed in this invention are as follows:

[0010] A low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism includes a ground plane 28. A circular metal cavity 29 is provided on the ground plane 28. A central antenna 32 is provided in the center of the metal cavity 29. Edge antennas 33 are distributed equidistantly and angularly around the outer periphery of the central antenna 32 within the circumference of the metal cavity 29. The central antenna 32 includes a central metal cavity 902 and a central antenna element 11 coaxially arranged within the central metal cavity 902. The edge antennas 33 include seven edge metal cavities 901. Each edge metal cavity 901 contains an edge antenna element 18. The edge antenna element 18 is an inscribed circle relative to the edge metal cavity 901, and the centers of each edge antenna element 18, edge metal cavity 901, central metal cavity 902, and central antenna element 11 are on a straight line.

[0011] The central antenna unit 11 includes an upper radiating structure and a lower radiating structure. The upper radiating structure includes an upper dielectric substrate 8, with a feeding metal cladding 1 disposed in the middle of the upper dielectric substrate 8, and an annular radiating metal cladding 2 disposed near the edge of the upper dielectric substrate 8 around the feeding metal cladding 1. The lower radiating structure includes a lower dielectric substrate 6, with a circular radiating metal cladding 7 disposed in the middle of the lower dielectric substrate 6. A metal feeding probe 5 penetrates the center of the feeding metal cladding 1, the upper dielectric substrate 8, the circular radiating metal cladding 7, and the lower dielectric substrate 6, and simultaneously feeds the upper and lower radiating structures. Multiple metal short-circuit posts 3 sequentially penetrate the annular radiating metal cladding 2, the upper dielectric substrate 8, and the lower dielectric substrate 6 to support the upper and lower radiating structures and serve as short circuits, and the metal short-circuit posts 3 are distributed at equal angles and intervals.

[0012] The feeding metal cladding 1, the annular radiating metal cladding 2, and the circular radiating metal cladding 7 are all printed with copper metal.

[0013] The lower radiating structure is provided with a first metallized through-hole 401 and a second metallized through-hole 402. The first metallized through-hole 401 and the second metallized through-hole 402 are located on the same straight line as the two opposite metal short-circuit posts 3 and the metal feed probe 5.

[0014] The power-feeding metal cladding 1 is in the shape of a seven-petaled plum blossom, with the petals distributed at equal angles and intervals.

[0015] The edge antenna unit 18 has the same structure as the center antenna unit 11. A dielectric lens cover plate 12 is placed directly above the center antenna 32 of the center antenna unit 11. Dielectric support columns 13 are arranged around the dielectric lens cover plate 12. The height of the dielectric support columns 13 is adjusted by adjusting bolts.

[0016] A dielectric lens antenna cover 30 is provided between the metal bottom cavity 29 and the edge metal cavity 901, and a groove is dug in the middle of the metal bottom cavity 29 to reduce its weight.

[0017] The dielectric lens radome 30 includes an inner radome layer 27 and an outer radome layer 26. The outer radome layer 26 is made of quartz cyanate ester material, and the inner radome layer 27 is made of PMI foam material.

[0018] The edge metal cavity 901 of the edge antenna 33 is provided with a first short-circuit post mounting countersink 14 that is adapted to the metal short-circuit post 3 of the edge antenna unit 18, and the center metal cavity 902 is provided with a second short-circuit post mounting countersink 17 that is adapted to the metal short-circuit post 3 of the center antenna unit 11.

[0019] Dielectric lens units 31 are arranged between adjacent edge antennas 33. Each dielectric lens unit 31 includes an elliptical dielectric block 25. An elliptical metal cladding 24 is provided on the elliptical dielectric block 25. Dielectric screws 2301 pass through the elliptical metal cladding 24 and the two sides of the elliptical dielectric block 25 respectively to fix the dielectric lens unit 31 to the circumference of the ground plane 28.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] In this invention, an annular radiating metal cladding layer 2 is printed on the upper surface of the upper dielectric substrate 8; a circular radiating metal cladding layer 7 is printed on the upper surface of the lower dielectric substrate 6. Four metal short-circuit posts 3 serve as short-circuit and support structures, forming an RLC resonant structure through the short-circuit action and reducing the low-frequency cutoff frequency. Furthermore, the coupling strength between the upper and lower substrates can be adjusted by controlling the height of the short-circuit posts. In small-sized antenna structures, the metal feed probes 5 are easier to process and solder. Additionally, by changing the spacing between the first metallized via 401 and the second metallized via 402 penetrating the lower dielectric substrate 6, the antenna impedance can be adjusted to achieve good impedance matching.

[0022] The central antenna element and the edge antenna element are embedded inside the central metal cavity 902 and the edge metal cavity 901, respectively. The central metal cavity 902 adopts a straight cavity form, while the edge metal cavity 901 adopts a crescent-shaped semi-expanding cavity form. This changes the propagation phase of the creeping wave along the cavity, giving the edge antenna element 18 better radiation characteristics. Furthermore, as edge metal cavities 901 and central metal cavities 902, they can reduce the current propagating to the metal bottom cavity 29, acting as an isolation grid and giving the antenna more stable characteristics.

[0023] A ring-shaped radiating metal cladding layer 2 is printed on the upper surface of the upper dielectric substrate 8; a circular radiating metal cladding layer 7 is printed on the upper surface of the lower dielectric substrate 6. This dual-layer vertical structure radiates in a vertically polarized manner. The distance between the first metallized via 401 and the second metallized via 402 and the center of the central antenna element 11 is adjusted to achieve TM... 01 and TM 02 The modulation of the radiation mode introduces a new resonant point to achieve a wide bandwidth for the antenna, thereby further expanding the operating bandwidth of the intracavity antenna. In addition, the upper antenna structure uses a plum blossom-shaped feeding metal cladding 1 to couple the feeding of the ring-shaped radiating metal cladding 2. This feeding method is equivalent to introducing a coupling capacitor into the circuit structure, which can further broaden the operating bandwidth of the antenna.

[0024] Seven dielectric lens elements 31 are evenly distributed at equal intervals and angles on the metal cavity 29. This distribution is equivalent to introducing an equivalent dummy element structure for the central antenna element 11, which guides the electromagnetic waves and keeps the intensity of electromagnetic radiation on the wavefront at the same distance from the central antenna element 11 stable, giving the antenna more stable radiation characteristics.

[0025] In summary, the upper radiating structure 8 and the lower radiating structure 6 of this invention are supported by four metal short-circuit pillars 3, which also adjust the spacing between the two radiating structures. This expands the antenna's operating bandwidth and achieves dual-resonance characteristics, thereby increasing the communication capacity of the airborne platform communication system. The hollowing-out treatment between the two radiators reduces the antenna's lateral dimension, achieving antenna miniaturization and saving more space resources on the airborne platform. The use of a crescent-shaped semi-expanding cavity for the edge metal cavity 901 and a straight cavity for the central metal cavity 902 acts as an isolation barrier, reducing the current propagating to the outside of the cavity and enhancing the anti-interference performance of the airborne platform antenna. The seven dielectric lens elements 31 are equidistantly and angularly distributed on the metal bottom cavity 29. This distribution is equivalent to introducing an equivalent dummy element structure for the central antenna element 11. The seven dielectric lens elements 31 have rotational symmetry characteristics, which can regulate the radiation pattern of the central antenna element 11, thereby enhancing the radiation characteristics of the airborne communication system. The monopole antenna of this invention features a low-profile design based on a lens mechanism, requiring only 0.15 low-frequency wavelengths to operate, compared to 0.25 low-frequency wavelengths required by traditional monopole antennas. This has strong practical application value in increasing the channel capacity and attenuation resistance of airborne platform communication and navigation systems, improving the overall system performance, and realizing high-performance communication and high-precision navigation on airborne platforms. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the overall structure of the antenna array of the present invention.

[0027] Figure 2 This is a diagram showing the radiation structure of the central antenna element and the edge antenna elements of the present invention.

[0028] Figure 3 This is a side view of the radiation structure of the central antenna element and the edge antenna element of the present invention.

[0029] Figure 4 This is a top view of the edge antenna 33 structure of the present invention.

[0030] Figure 5 This is a top view of the central antenna 32 structure of the present invention.

[0031] Figure 6 This is a top view of the dielectric lens cover plate 12 of the central antenna unit of the present invention.

[0032] Figure 7 This is a top view of the edge metal cavity 901 of the edge antenna unit 18 of the present invention.

[0033] Figure 8 This is a top view of the central metal cavity 902 of the central antenna unit 18 of the present invention.

[0034] Figure 9 This is a diagram showing the relationship between the antenna array dielectric lens radome, the dielectric lens unit, and the metal cavity 29 of the present invention.

[0035] Figure 10 This is a structural diagram of the dielectric lens unit 31 of the present invention.

[0036] Figure 11 This is a structural diagram of the dielectric lens antenna radome 30 of the present invention.

[0037] Figure 12 This is a voltage standing wave ratio (VSWR) curve corresponding to the eight ports of the antenna array of this invention.

[0038] Figure 13 This is the azimuth pattern of antenna port 1 of the present invention at 3.35 GHz.

[0039] Figure 14 This is the azimuth pattern of antenna port 2 of the present invention at 3.35 GHz.

[0040] Figure 15 This is the azimuth radiation pattern of antenna port 3 of the present invention at 3.35 GHz.

[0041] Figure 16 This is the azimuth radiation pattern of antenna port 4 of the present invention at 3.35 GHz.

[0042] Figure 17 This is the azimuth radiation pattern of antenna port 5 of the present invention at 3.35 GHz.

[0043] Figure 18 This is the azimuth radiation pattern of antenna port 6 of the present invention at 3.35 GHz.

[0044] Figure 19 This is the azimuth radiation pattern of antenna port 7 of the present invention at 3.35 GHz.

[0045] Figure 20 This is the azimuth radiation pattern of antenna port 8 of the present invention at 3.35 GHz.

[0046] In the figure: 1. Feed metal cladding; 2. Annular radiating metal cladding; 3. Copper metal short-circuit post; 401. First metallized via; 402. Second metallized via; 5. Metal feed probe; 6. Lower dielectric substrate; 7. Circular radiating metal cladding; 8. Upper dielectric substrate; 901. Edge metal cavity; 902. Central metal cavity; 10. First bottom countersunk hole; 11. Central antenna element; 12. Dielectric lens cover; 13. Dielectric support post; 14. 15. Countersunk hole for mounting short-circuit post; 16. Central cavity flange adapter plate; 17. Second bottom countersunk hole; 18. Second short-circuit post mounting countersunk hole; 19. Edge antenna element; 20. Edge cavity flange adapter plate; 21. Dielectric screw; 22. Elliptical dielectric cover layer; 23. Elliptical dielectric block; 24. Outer layer of radome; 25. Inner layer of radome; 26. Ground plane; 27. Metal bottom cavity; 38. Dielectric lens radome; 39. Dielectric lens element; 30. Central antenna; 31. Edge antenna. Detailed Implementation

[0047] The present invention will now be described in detail with reference to the accompanying drawings.

[0048] See Figures 1 to 5 A low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism includes a ground plane 28. A circular metal cavity 29 is provided on the ground plane 28. A central antenna 32 is provided in the center of the metal cavity 29. Edge antennas 33 are distributed equidistantly and angularly around the outer periphery of the central antenna 32 within the circumference of the metal cavity 29. The central antenna 32 includes a central metal cavity 902 and a central antenna element 11 coaxially arranged within the central metal cavity 902. The edge antennas 33 include seven edge metal cavities 901. Each edge metal cavity 901 contains an edge antenna element 18. The edge antenna element 18 is an inscribed circle relative to the edge metal cavity 901, and the centers of each edge antenna element 18, edge metal cavity 901, central metal cavity 902, and central antenna element 11 are on a straight line.

[0049] The central antenna unit 11 includes an upper radiating structure and a lower radiating structure. The upper radiating structure includes an upper dielectric substrate 8, with a feeding metal cladding 1 disposed in the middle of the upper dielectric substrate 8, and an annular radiating metal cladding 2 disposed near the edge of the upper dielectric substrate 8 on the outer periphery of the feeding metal cladding 1. The lower radiating structure includes a lower dielectric substrate 6, with a circular radiating metal cladding 7 disposed in the middle of the lower dielectric substrate 6. A metal feeding probe 5 penetrates the center of the feeding metal cladding 1, the upper dielectric substrate 8, the circular radiating metal cladding 7, and the lower dielectric substrate 6, and simultaneously feeds the upper and lower radiating structures. Four metal short-circuit posts 3 sequentially penetrate the annular radiating metal cladding 2, the upper dielectric substrate 8, and the lower dielectric substrate 6 to support the upper and lower radiating structures and serve as short circuits, and the four short-circuit posts 3 are distributed at equal angles and intervals.

[0050] The feeding metal cladding 1, the annular radiating metal cladding 2, and the circular radiating metal cladding 7 are all printed with copper metal.

[0051] The lower radiating structure is provided with a first metallized through hole 401 and a second metallized through hole 402. The first metallized through hole 401 and the second metallized through hole 402 are located on the same straight line as the two opposite metal short-circuit posts 3 and the metal feed probe 5, and are 9.8 mm away from the center of the lower radiating structure, with an error not exceeding ±0.2 mm.

[0052] The radius of the feeding metal cladding 1 is 3.6 mm, with an error not exceeding ±0.2 mm; the inner radius of the annular radiating metal cladding 2 is 10.5 mm, and the outer radius is 12.1 mm, with an error not exceeding ±0.2 mm; the radius of the circular radiating metal cladding 7 is 11.5 mm, with an error not exceeding ±0.2 mm.

[0053] The power-feeding metal cladding 1 is in the shape of a seven-petaled plum blossom, with the petals distributed at equal angles and intervals.

[0054] The edge antenna element 18 has the same structure as the center antenna element 11. The radius of the feed metal cladding of the edge antenna element 18 is 4.6 mm, with an error not exceeding ±0.2 mm.

[0055] See Figure 5 , Figure 6 The center distance between the edge antenna unit 18 and the center of the metal cavity 29 is 105mm, with an error not exceeding ±0.2mm. A dielectric lens cover plate 12 is placed directly above the center antenna 32. Dielectric support columns 13 are arranged around the dielectric lens cover plate 12, and the height of the dielectric support columns 13 is adjusted by adjusting bolts.

[0056] The central metal cavity 902 of the central antenna 32 is located in the middle of the metal bottom cavity 29; the edge metal cavity 901 of the edge antenna 33 is located within the circumference of the ground plane 28.

[0057] See Figures 7 to 11 A dielectric lens antenna cover 30 is provided between the metal bottom cavity 29 and the edge metal cavity 901, and a groove is dug in the middle of the metal bottom cavity 29 to reduce its weight.

[0058] The dielectric lens radome 30 includes an inner radome layer 27 and an outer radome layer 26. The outer radome layer 26 is made of quartz cyanate ester material, and the inner radome layer 27 is made of PMI foam material.

[0059] The edge metal cavity 901 of the edge antenna 33 is provided with a first short-circuit post mounting countersink 14 that is adapted to the metal short-circuit post 3 of the edge antenna unit 18, and the center metal cavity 902 is provided with a second short-circuit post mounting countersink 17 that is adapted to the metal short-circuit post 3 of the center antenna unit 11.

[0060] Dielectric lens units 31 are arranged between adjacent edge antennas 33. Each dielectric lens unit 31 includes an elliptical dielectric block 25, on which an elliptical metal cladding 24 is provided. Two dielectric screws 2301 pass through the elliptical metal cladding 24 and the two sides of the elliptical dielectric block 25 respectively, fixing the dielectric lens unit 31 to the circumference of the ground plane 28. The center of the dielectric lens unit 31 is 110mm away from the center of the metal cavity, with an error not exceeding ±0.2mm.

[0061] This invention achieves wideband impedance characteristics within a small size by constructing a low-profile, common-aperture omnidirectional array antenna element and its array for an S-band airborne platform. Simultaneously, it realizes dual-frequency resonance characteristics within a high-Q metallic cavity structure. Furthermore, the radiation characteristics of the central element are adjusted by loading a dielectric lens, and the decoupling problem of a uniform circular omnidirectional array element antenna is solved through an irregularly shaped metallic cavity structure. This invention can be used not only for super-resolution direction finding but also for communication on airborne platforms. The excellent port and radiation characteristics also contribute to improving the overall performance of integrated communication and navigation systems, thereby achieving high-performance direction finding and communication.

[0062] 1. Simulation Content

[0063] The antenna of the above embodiment was simulated using simulation software. The voltage standing wave ratio and radiation pattern of the antenna are shown below. Figures 12 to 20 .

[0064] 2. Simulation Results

[0065] Figure 12The figure shows the voltage standing wave ratio (VSWR) as a function of operating frequency, obtained from the simulation of the antenna in the embodiment. When the VSWR is less than 1.5, the array antenna has eight ports: the center antenna element and seven edge antenna elements (edge ​​antenna elements 1 to 7). The center antenna element can operate in the S-band from 3.24 GHz to 3.46 GHz, and the seven edge antenna elements can all operate in the S-band from 3.26 GHz to 3.43 GHz. This result indicates that the antenna of the present invention achieves good port matching characteristics.

[0066] Figure 13 This figure shows the gain pattern of the central element in the azimuth plane obtained from the antenna simulation of the embodiment. The antenna is a vertically polarized beam across the entire frequency band. The figure shows the pattern at an elevation angle of 90°. The maximum gain for the main polarization is 0.72 dB, and the minimum gain is 0.11 dB. The maximum gain for the cross-polarization is -20.9 dB, and the minimum gain is -53.2 dB. The results demonstrate that the antenna of this invention has high cross-polarization isolation and stable gain characteristics.

[0067] Figures 14-20 This figure shows the gain pattern of the central element in the azimuth plane obtained from the antenna simulation of the embodiment. The antenna is a vertically polarized beam across the entire frequency band. The figure shows the pattern at an elevation angle of 90°. The maximum gain for the main polarization is 1.97 dB, and the minimum gain is -2.92 dB. The maximum gain for the cross-polarization is -20.3 dB, and the minimum gain is -50.9 dB. The results demonstrate that the antenna of this invention has high cross-polarization isolation and stable gain characteristics.

[0068] The above are merely the preferred embodiments of the present invention and do not constitute any limitation on the present invention. Obviously, under the concept of the present invention, the structure, parameters and frequency of the present invention can be modified to obtain the broadband characteristics and high isolation characteristics (cross-polarization isolation) of the antenna of the present invention, as well as to realize the modularity and arraying of the antenna, but these are all within the scope of protection of the present invention.

Claims

1. A low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism, comprising a ground plane (28), characterized in that: The ground plane (28) is provided with a circular metal cavity (29), and a central antenna (32) is provided in the middle of the metal cavity (29). Edge antennas (33) are distributed equidistantly and angularly around the outer periphery of the central antenna (32) within the circumference of the metal cavity (29). The central antenna (32) includes a central metal cavity (902) and a central antenna unit (11) coaxially arranged within the central metal cavity (902). The edge antennas (33) include 7 edge metal cavities (901). Each edge metal cavity (901) is provided with an edge antenna unit (18). The edge antenna unit (18) is an inscribed circle relative to the edge metal cavity (901), and the center of each edge antenna unit (18), edge metal cavity (901), central metal cavity (902), and central antenna unit (11) is on a straight line. The central metal cavity (902) is in the form of a straight cavity, and the edge metal cavity (901) is in the form of a crescent-shaped semi-expanded cavity.

2. The low-profile omnidirectional array antenna for an airborne platform based on lens mechanism according to claim 1, characterized in that: The central antenna unit (11) includes an upper radiation structure and a lower radiation structure. The upper radiation structure includes an upper dielectric substrate (8), with a feeding metal cladding (1) in the middle of the upper dielectric substrate (8) and an annular radiating metal cladding (2) near the edge of the upper dielectric substrate (8) on the outer periphery of the feeding metal cladding (1). The lower radiation structure includes a lower dielectric substrate (6), with a circular radiating metal cladding (7) in the middle of the lower dielectric substrate (6). The metal feeding probe 5 penetrates the center of the feeding metal cladding (1), the upper dielectric substrate (8), the circular radiating metal cladding (7), and the lower dielectric substrate (6), and feeds the upper and lower radiation structures simultaneously. The metal short-circuit posts (3) penetrate the annular radiating metal cladding (2), the upper dielectric substrate (8), and the lower dielectric substrate (6) in sequence, supporting the upper and lower radiation structures and acting as short circuits. The multiple metal short-circuit posts (3) are distributed at equal angles and intervals.

3. The low-profile omnidirectional array antenna for an airborne platform based on lens mechanism according to claim 2, characterized in that: The feeding metal cladding (1), the annular radiating metal cladding (2) and the circular radiating metal cladding (7) are all printed with copper metal.

4. The low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism according to claim 2, characterized in that: The lower radiation structure is provided with a first metallized through hole (401) and a second metallized through hole (402). The first metallized through hole (401) and the second metallized through hole (402) are located on the same straight line as the two metal short-circuit posts (3) and the metal feed probe (5).

5. A low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism, as described in claim 2 or 3, characterized in that: The power-feeding metal cladding (1) is in the shape of a seven-petaled plum blossom, with the petals distributed at equal angles and intervals.

6. The low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism according to claim 1, characterized in that: The edge antenna unit (18) has the same structure as the center antenna unit (11); a dielectric lens cover plate (12) is placed directly above the center antenna (32) of the center antenna unit (11), and dielectric support columns (13) are arranged around the dielectric lens cover plate (12). The height of the dielectric support columns (13) is adjusted by adjusting bolts.

7. The low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism according to claim 1, characterized in that: A dielectric lens antenna cover (30) is provided between the metal bottom cavity (29) and the edge metal cavity (901). A groove is dug in the middle of the metal bottom cavity (29) to reduce its weight. Seven dielectric lens units (31) are uniformly distributed at equal intervals and angles on the metal bottom cavity (29).

8. The low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism according to claim 7, characterized in that: The dielectric lens radome (30) includes an inner radome layer (27) and an outer radome layer (26). The outer radome layer (26) is made of quartz cyanate material, and the inner radome layer (27) is made of PMI foam material.

9. A low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism according to claim 1, characterized in that: The edge metal cavity (901) of the edge antenna (33) is provided with a first short-circuit post mounting countersink (14) that is adapted to the metal short-circuit post (3) of the edge antenna unit (18), and the center metal cavity (902) is provided with a second short-circuit post mounting countersink (17) that is adapted to the metal short-circuit post (3) of the center antenna unit (11).

10. The low-profile omnidirectional array antenna for an airborne platform based on a lens mechanism according to claim 9, characterized in that: Dielectric lens units (31) are arranged between adjacent edge antennas (33). The dielectric lens unit (31) includes an elliptical dielectric block (25). An elliptical metal cladding (24) is provided on the elliptical dielectric block (25). Dielectric screws (2301) pass through the elliptical metal cladding (24) and the two sides of the elliptical dielectric block (25) respectively to fix the dielectric lens unit (31) to the circumference of the ground plane (28).

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