Miniaturized anti-interference dual-frequency antenna and application thereof

Abstract

The invention discloses a miniaturized anti-interference dual-frequency antenna and application thereof.The miniaturized anti-interference dual-frequency antenna comprises a sheet-shaped antenna assembly, a dual-frequency double-fed antenna assembly, a first grounding plate, a shielding cover and a second grounding plate, and the sheet-shaped antenna assembly sequentially comprises a plurality of sheet-shaped antennas of the same shape and structure from top to bottom; wherein each sheet-shaped antenna comprises a sheet-shaped antenna dielectric layer and a metal layer arranged below the sheet-shaped antenna dielectric layer. The invention provides the dual-frequency antenna with excellent anti-interference performance, and the dual-frequency antenna is particularly suitable for application scenes such as unmanned aerial vehicles and the like. According to the antenna, a plurality of sheet-shaped antennas and plastic columns with different heights are introduced, and a radiation pattern is optimized, so that the inhibition capability on a back lobe level is remarkably improved, the potential interference of surface current of a fuselage of an unmanned aerial vehicle on antenna radiation is reduced, and the overall performance of the antenna is enhanced.

Description

Technical Field

[0001] The present invention belongs to the technical field of antennas, and particularly relates to a miniaturized anti-interference dual-band antenna and its application. Background Art

[0002] In recent years, unmanned aerial vehicle (UAV) technology has been widely applied in military and civilian fields, such as reconnaissance and monitoring, logistics transportation, environmental monitoring, and emergency rescue. With the complexity of application scenarios, UAVs have put forward higher requirements for the stability, anti-interference ability, and spectrum utilization efficiency of communication systems. Among them, as a key component of the UAV wireless communication system, the performance of the antenna directly affects the reliability of data transmission and the anti-interference ability.

[0003] Currently, UAVs usually use single-band or dual-band antennas for wireless communication, such as Wi-Fi and dedicated data links in the 2.4 GHz and 5.8 GHz frequency bands. However, the existing miniaturized dual-band antennas still have the following main problems on the UAV platform:

[0004] 1. Insufficient anti-interference ability: UAVs usually operate in a complex electromagnetic environment and are vulnerable to interference from co-frequency or adjacent-frequency signals, resulting in a decline in communication quality or even signal loss. Some existing antennas lack effective anti-interference designs, such as notch characteristics, directivity optimization, or anti-interference filter structures, making their communication stability low in a strong interference environment.

[0005] 2. Difficulty in balancing miniaturization and performance: UAVs have extremely strict requirements for payload and size, and the antenna needs to be lightweight and miniaturized. However, when traditional dual-band antennas reduce their volume, they often sacrifice gain, bandwidth, or radiation efficiency, affecting the communication coverage and signal quality.

[0006] 3. Limited frequency band selection: Some existing UAV dual-band antennas perform well in specific frequency bands (such as 2.4 GHz and 5.8 GHz), but when extended to a wider spectrum (such as the L band or C band), there are problems such as matching difficulties and resonance point drift, which limit the adaptability of UAVs in multiple scenarios.

[0007] Based on the above problems, it is crucial to develop a dual-band antenna with miniaturization, high gain, wide bandwidth, and excellent anti-interference ability for improving the reliability of the UAV communication system. Summary of the Invention

[0008] The object of the present invention is to provide an application of a miniaturized anti-interference dual-frequency antenna carried by an unmanned aerial vehicle (UAV) to address the problems of difficulty in balancing miniaturization and performance, and insufficient anti-interference ability. By using parasitic elements of patch antennas and stacking them above the antenna elements, part of the sidelobe gain is transferred to the main lobe, strengthening the gain of the antenna in the main lobe, enabling the antenna to better operate in a circular polarization state to achieve anti-interference in the back lobe direction. In terms of area, through optimization, the area of the ground plane is reduced, thus achieving better miniaturization characteristics.

[0009] To achieve the above object, the present invention adopts the following technical solutions:

[0010] In a first aspect, the present invention provides a miniaturized anti-interference dual-frequency antenna, comprising:

[0011] A patch antenna assembly;

[0012] A dual-frequency dual-feed antenna assembly, which is disposed below the patch antenna assembly; the dual-frequency dual-feed antenna assembly includes a stacked first antenna unit and a second antenna unit;

[0013] A first ground plane, which is disposed below the dual-frequency dual-feed antenna assembly;

[0014] A shielding cover, which is disposed below the first ground plane;

[0015] A second ground plane, which is disposed below the shielding cover;

[0016] The patch antenna assembly sequentially includes a plurality of patch antennas with the same shape and structure from top to bottom. Each patch antenna includes a patch antenna dielectric layer and a metal layer disposed below the patch antenna dielectric layer. A support column is provided between each patch antenna; the centers of the patch antennas overlap.

[0017] Specifically, the patch antenna assembly includes a first patch antenna, a second patch antenna, a third patch antenna, and a fourth patch antenna. A first support column is provided between the first patch antenna and the second patch antenna, a second support column is provided between the second patch antenna and the third patch antenna, a third support column is provided between the third patch antenna and the fourth patch antenna, and a fourth support column is provided between the fourth patch antenna and the first ground plane.

[0018] Preferably, the heights of the support columns are not all the same.

[0019] Preferably, the outer shapes of the first patch antenna, the second patch antenna, the third patch antenna, and the fourth patch antenna are all rectangular, and can also be changed to cross-shaped or circular.

[0020] Preferably, the first ground plane includes a first metal layer of the first ground plane, a first dielectric layer of the first ground plane disposed below the first metal layer of the first ground plane, and a second metal layer of the first ground plane disposed below the first dielectric layer of the first ground plane; the first metal layer of the first ground plane serves as the ground plane of the dual-band dual-feed antenna assembly; an etched circuit is engraved on the surface of the second metal layer of the first ground plane.

[0021] Preferably, the etched circuit includes a combiner circuit, a first resistor, a second resistor, a first hybrid coupler, and a second hybrid coupler; the combiner circuit includes a first port, a second port, and a third port, wherein the first port and the second port are connected by a first microstrip line, and the first port and the third port are connected by a second microstrip line; one end of the first hybrid coupler is connected to the second port, and the other end is connected to the first resistor; one end of the second hybrid coupler is connected to the third port, and the other end is connected to the second resistor.

[0022] Preferably, in the first antenna unit, it includes a first radiator, a first dielectric, a first coaxial probe, and a second coaxial probe; the first dielectric and the first metal layer of the first ground plane are both provided with a first through hole and a second through hole, the first coaxial probe penetrates through the first through hole and the first ground plane, the second coaxial probe penetrates through the second through hole and the first ground plane, and the first coaxial probe and the second coaxial probe are respectively in contact with the first radiator and the first hybrid coupler at both ends; there is an air dielectric between the first coaxial probe and the inner wall of the first through hole, and there is an air dielectric between the second coaxial probe and the inner wall of the second through hole.

[0023] Preferably, in the second antenna unit, it includes a second radiator, a second dielectric, a third coaxial probe, and a fourth coaxial probe; the second dielectric and the first metal layer of the first ground plane are both provided with a third through hole and a fourth through hole, the second radiator and the second dielectric are both provided with a fifth through hole and a sixth through hole, the third coaxial probe penetrates through the third through hole and the first ground plane, the fourth coaxial probe penetrates through the fourth through hole and the first ground plane, and the third coaxial probe and the fourth coaxial probe are respectively in contact with the second radiator and the second hybrid coupler at both ends; there is an air dielectric between the third coaxial probe and the inner wall of the third through hole, there is an air dielectric between the fourth coaxial probe and the inner wall of the fourth through hole, there is an air dielectric between the first coaxial probe and the inner wall of the fifth through hole, and there is an air dielectric between the second coaxial probe and the inner wall of the sixth through hole.

[0024] Preferably, the operating frequencies of the first antenna unit and the second antenna unit are in the L band.

[0025] Preferably, the shielding cover is a hollow square column structure with four corners cut off, which can completely cover the dual-band dual-feed antenna assembly and the etched circuit.

[0026] Preferably, metal posts are provided on the second ground plane, and the metal posts are used to fix the second ground plane.

[0027] Preferably, the second ground plane is used to support the shielding cover.

[0028] Preferably, the diameter of the second ground plane is larger than the diameter of the shielding cover.

[0029] More preferably, the materials of the first medium and the second medium are ceramics, and the first, second, third, and fourth sheet antenna dielectric layers and the first ground plane dielectric layer are all made of FR4 boards.

[0030] In a second aspect, the present invention also provides an application of the miniaturized anti-interference dual-band antenna on an unmanned aerial vehicle.

[0031] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] The present invention provides a dual-band antenna with excellent anti-interference performance and miniaturization characteristics, which is particularly suitable for application scenarios such as unmanned aerial vehicles. Through a special structural design, it achieves better anti-interference characteristics and higher gain on the main lobe to enable better reception of satellite signals. Specifically, by introducing a plurality of sheet antenna components and plastic posts with different heights above the antenna element, and by optimizing the radiation pattern, the gain of the main lobe is significantly improved and the level of the back lobe is suppressed. The antenna operates in a better circular polarization state, thereby reducing the potential interference of the unmanned aerial vehicle to other radiations and enhancing the overall performance of the antenna. In addition, the stacked antenna units and sheet antenna components used in the present invention can make the antenna occupy a smaller area on the x and y axes, achieving the characteristics of miniaturization. Description of the Drawings

[0033] In order to more clearly illustrate the technical solutions of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1 is a three-dimensional view of the miniaturized anti-interference antenna of the present invention.

[0035] Figure 2 is a side view of the miniaturized anti-interference antenna of the present invention.

[0036] Figure 3 is a top view of the first sheet antenna of the present invention.

[0037] Figure 4 is a stacked view of the dual-band dual-feed antenna assembly of the present invention.

[0038] Figure 5 It is a top view of the dual - frequency and dual - feed antenna assembly of the present invention.

[0039] Figure 6 It is a top view of the second antenna unit of the present invention.

[0040] Figure 7 It is a top view of the first ground plane of the present invention.

[0041] Figure 8 It is a schematic diagram of the etched circuit of the present invention.

[0042] Figure 9 It is a schematic diagram of the combiner circuit of the present invention.

[0043] Figure 10 It is a top view of the shielding cover of the present invention.

[0044] Figure 11 It is a side view of the shielding cover of the present invention.

[0045] Figure 12 It is a top view of the second ground plane of the present invention.

[0046] Figure 13 It is a simulation result diagram of S11 and S22 of the present invention.

[0047] Figure 14 It is the radiation pattern when the present invention operates at 1.176 GHz without loading the patch antenna assembly.

[0048] Figure 15 It is the radiation pattern when the present invention operates at 1.176 GHz with loading the patch antenna assembly.

[0049] Figure 16 It is the radiation pattern when the present invention operates at 1.575 GHz without loading the patch antenna assembly.

[0050] Figure 17 It is the radiation pattern when the present invention operates at 1.575 GHz with loading the patch antenna assembly.

[0051] Markings in the figure: 1. Sheet antenna assembly; 11. First sheet antenna; 111. First sheet antenna dielectric layer; 112. First sheet antenna metal layer; 113. First support column; 12. Second sheet antenna; 121. Second sheet antenna dielectric layer; 122. Second sheet antenna metal layer; 123. Second support column; 13. Third sheet antenna; 131. Third sheet antenna dielectric layer; 132. Third sheet antenna metal layer; 133. Third support column; 14. Fourth sheet antenna; 141. Fourth sheet antenna dielectric layer; 142. Fourth sheet antenna metal layer; 143. Fourth support column; 2. Dual - frequency and dual - feed antenna assembly; 21. First antenna unit; 211. First radiator; 212. First dielectric; 213. First through - hole; 214. First coaxial probe; 215. Second through - hole; 216. Second coaxial probe; 22. Second antenna unit; 221. Second radiator; 222. Second dielectric; 223. Third through - hole; 224. Third coaxial probe; 225. Fourth through - hole; 226. Fourth coaxial probe; 227. Fifth through - hole; 228. Sixth through - hole; 3. First ground plane; 31. First metal layer of the first ground plane; 32. Dielectric layer of the first ground plane; 33. Second metal layer of the first ground plane; 34. Etched circuit; 341. First hybrid coupler; 342. Second hybrid coupler; 343. First resistor; 344. Second resistor; 345. Combiner circuit; 3451. First port; 3452. First microstrip line; 3453. Second port; 3454. Second microstrip line; 3455. Third port; 4. Shielding cover; 5. Second ground plane; 51. Metal post. Detailed implementation mode

[0052] Next, in combination with the embodiments of the present invention, the technical solutions of the present invention will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0053] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first", "second", etc. may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0054] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "mounted", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood through specific circumstances.

[0055] The present invention will be described in detail below with reference to the drawings and in conjunction with embodiments.

[0056] Refer to Figures 1-3 As shown, it is a three-dimensional view, a side view, and a top view of the first patch antenna 11 of the miniaturized anti-interference antenna of the present invention, which includes: a patch antenna assembly 1, a dual-band dual-feed antenna assembly 2, a first ground plane 3, a shielding cover assembly 4, and a second ground plane 5; the patch antenna assembly 1 includes: a first patch antenna 11, a second patch antenna 12, a third patch antenna 13, and a fourth patch antenna 14, and their outer shapes are all rectangular, and can also be changed to a cross shape or a circular shape; in a preferred embodiment of the present invention, the outer shapes of the first patch antenna 11, the second patch antenna 12, the third patch antenna 13, and the fourth patch antenna 14 are square.

[0057] The basic structures of the first patch antenna 11, the second patch antenna 12, the third patch antenna 13, and the fourth patch antenna 14 are the same. Taking the first patch antenna 11 as an example, it includes a first patch antenna dielectric layer 111, a first patch antenna metal layer 112, and a first support post 113. The first patch antenna dielectric layer 111 is made of FR4 board with a side length of s1 = 9.8 mm, and the first patch antenna metal layer 112 has a side length of s2 = 5.2 mm. Similarly, the second patch antenna 12 includes a second patch antenna dielectric layer 121, a second patch antenna metal layer 122, and a second support post 123. The third patch antenna 13 includes a third patch antenna dielectric layer 131, a third patch antenna metal layer 132, and a third support post 133. The fourth patch antenna 14 includes a fourth patch antenna dielectric layer 141, a fourth patch antenna metal layer 142, and a fourth support post 143. Among them, the first support post 113, the second support post 123, and the third support post 133 have the same height. The column diameters of the first support post 113, the second support post 123, the third support post 133, and the fourth support post 143 are dr1 = 4 mm, and the four are connected to penetrate and fix the first patch antenna 11, the second patch antenna 12, and the third patch antenna 13. The fourth support post 143 fixes the patch antenna assembly 1 to the first ground plane 3. The first support post 113, the second support post 123, the third support post 133, and the fourth support post 143 are made of plastic.

[0058] The first ground plane 3 includes: a first ground plane first metal layer 31, a first ground plane dielectric layer 32, a first ground plane second metal layer 33, and an etched circuit 34.

[0059] Refer to Figures 4-6As shown, it is the side view and top view of the L1 / L5 dual-band dual-feed antenna assembly 2 of the present invention and the top view of the second antenna unit 22; the dual-band dual-feed antenna assembly 2 includes a first antenna unit 21 and a second antenna unit 22, specifically including: a first radiator 211, a first dielectric 212, a first through hole 213, a first coaxial probe 214, a second through hole 215, a second coaxial probe 216, a second radiator 221, a second dielectric 222, a third through hole 223, a third coaxial probe 224, a fourth through hole 225, a fourth coaxial probe 226, a fifth through hole 227, and a sixth through hole 228; the first radiator 211 and the second radiator 221 are silver layers printed on the surface of ceramic dielectrics, the silver layers are square structures, the length pw2 of the first radiator 211 is 20 mm, and there is a rectangular protrusion fw2 = 6 mm at the center of the four sides. The length pw1 of the second radiator 221 is 30 mm, and there is a rectangular protrusion fw1 = 8 mm at the center of the four sides. The relative dielectric constant εr of the first dielectric 212 is 12, the ceramic thickness td1 is 4 mm, and the length cw2 is 25 mm. There is air dielectric inside the inner walls of the first through hole 213 and the second through hole 215; the first through hole 213 and the second through hole 215 are to prevent the first coaxial probe 214 and the second coaxial probe 216 from short-circuiting with the first dielectric 212, and the side length ag1 is 2 mm; the first through hole 213 and the second through hole 215 overlap with the centers of the first coaxial probe 214 and the second coaxial probe 216 on the z-axis; the first through hole 213 is in the negative x-axis direction and is 3 mm away from the unit center; the second through hole 215 is in the positive y-axis direction and is 3 mm away from the unit center. The upper and lower ends of the first coaxial probe 214 and the second coaxial probe 216 are connected to the first radiator 211 and the first hybrid coupler 341 respectively, and are not connected to each other, and are not directly connected to the first dielectric 212, the second radiator 221, the second dielectric 222, the third coaxial probe 224, and the fourth coaxial probe 226. The second radiator 221 is penetrated by the fifth through hole 227 and the sixth through hole 228, and the side length of the square of the fifth through hole 227 and the sixth through hole 228 is ag1 = 2 mm. The relative dielectric constant εr of the second dielectric 222 is 12, the ceramic thickness td2 is 6 mm, and the length cw1 is 40 mm. There is air dielectric inside the inner walls of the third through hole 223 and the fourth through hole 225; the third through hole 223 and the fourth through hole 225 are to prevent the third coaxial probe 224 and the fourth coaxial probe 226 from short-circuiting with the second dielectric 222, and the side length is ag1 = 2 mm; the third through hole 223 and the fourth through hole 225 overlap with the centers of the third coaxial probe 224 and the fourth coaxial probe 226 on the z-axis; the third through hole 223 is in the negative y-axis direction and is 3 mm away from the unit center; the fourth through hole 225 is in the positive x-axis direction and is 3 mm away from the unit center.The upper and lower ends of the third coaxial probe 224 and the fourth coaxial probe 226 are connected to the second radiator 221 and the second hybrid coupler 342 respectively, without being connected to each other and not directly connected to the second dielectric 222, the first coaxial probe 214, and the second coaxial probe 216. The inner walls of the fifth through hole 227 and the sixth through hole 228 have an air dielectric; the fifth through hole 227 is connected to the first through hole 213, and the sixth through hole 228 is connected to the second through hole 215; the fifth through hole 227 and the sixth through hole 228 are provided to prevent the first coaxial probe 214 and the second coaxial probe 216 from having a side length of ag1 = 2 mm with the second dielectric 222; the fifth through hole 227 and the sixth through hole 228 overlap with the first through hole 213 and the second through hole 215 on the z-axis. In the first antenna unit 21, the first coaxial probe 214 and the second coaxial probe 216 output two linearly polarized signals that are orthogonal to each other, have the same amplitude, and have a phase difference of 90 degrees, where the phase of the signal of the second coaxial probe 216 leads the signal of the first coaxial probe 214 by 90 degrees; its operating frequency is 1.575 GHz in the L band, that is, the L5 band. In the second antenna unit 22, the third coaxial probe 224 and the fourth coaxial probe 226 output two linearly polarized signals that are orthogonal to each other, have the same amplitude, and have a phase difference of 90 degrees, where the phase of the signal of the third coaxial probe 224 leads the signal of the fourth coaxial probe 226 by 90 degrees; its operating frequency is 1.176 GHz in the L band, that is, the L1 band.

[0060] As Figure 7 shown, it is a top view of the first ground plane 3 of the present invention. On the first ground plane 3, there are hollow through holes including the first through hole 213, the second through hole 215, the fifth through hole 227, and the sixth through hole 228 on the z-axis. The purpose is to prevent the first coaxial probe 214, the second coaxial probe 216, the third coaxial probe 224, and the fourth coaxial probe 226 from being connected to the first metal layer 31, the first ground plane dielectric layer 32, and the second metal layer 33 of the first ground plane; on the first ground plane 3, there are hollow through holes including the patch antenna assembly 1 on the z-axis. The purpose is to fix the antenna assembly 1 on the first ground plane 3; on the first ground plane 3, there are hollow through holes including the metal post 51 on the z-axis. The purpose is to fix the metal post 51. The parameters of the ground plane are: diameter d2 = 15 cm, drilling diameter dr1 = 4 mm, spacing g1 = 1.9 cm, and thickness th = 0.8 mm.

[0061] As Figures 8-9As shown in the figure, it is a schematic diagram of the etching circuit 34 of the present invention and a top view of the combiner circuit 345, which includes: a first hybrid coupler 341, a second hybrid coupler 342, a first resistor 343, a second resistor 344, a combiner circuit 345, a first port 3451, a first microstrip line 3452, a second port 3453, a second microstrip line 3454, and a third port 3455; the functions of the first hybrid coupler 341 and the second hybrid coupler 342 are to synthesize two linearly polarized waves that intersect each other with the same amplitude and a phase difference of 90 degrees and output a right-handed circularly polarized device. The first resistor 343 and the second resistor 344 are used to achieve impedance matching, and the resistance values are R1 = 50 Ω. The combiner circuit 345 is a three-port circuit device, which is a two-input and one-output circuit in the etching circuit 34, and its function is to combine two different frequency signals into the same output. The first microstrip line 3452 and the second port 3453 are L5 band lines, and the second microstrip line 3454 and the third port 3455 are L1 band lines. The dimensions of each transmission line segment are as follows: ml1 = 16 mm, ml2 = 15 mm, mw1 = 0.4 mm, mw2 = 0.7 mm, mw3 = 1.6 mm, mw4 = 0.2 mm, mw5 = 0.3 mm, mw6 = 0.7 mm.

[0062] As Figures 10-11 shown, it is a top view and a side view of the shielding cover 4 of the present invention. The shielding cover 4 is arranged below the first ground plane 3, and further below the second ground plane 5. It is a hollow square column structure with four corners cut off. The center of the shielding cover coincides with the center of the first ground plane in the vertical direction and can completely cover the etching circuit 34. The dimensions of the shielding cover are hw = 10 cm, the cut-off angle hq = 2.5 cm, the wall thickness ht = 1 mm, and the height hh = 1.4 mm. The dual-frequency dual-feed antenna assembly 2 is located above the hollow space area of the shielding cover 4. The dual-frequency dual-feed antenna assembly 2 is symmetric about the graphic center of the shielding cover 4 and also symmetric about the center of the circle of the ground plane 3.

[0063] As Figure 12 shown, it is a top view of the second ground plane assembly 5 of the present invention, which includes: a second ground plane 5 and metal posts 51 arranged on the second ground plane 5; among them, through holes are provided on the second ground plane 5, which are fixed slots for the metal posts 51, used to fix the second ground plane 5 under the first ground plane 3, and the shielding cover 4 is clamped between the first ground plane 3 and the second ground plane 5 to fix the position. Its parameters are: d3 = 8 mm, hh = 1.4 mm.

[0064] Further, the sheet antenna assembly of the present invention is characterized in that the antenna radiation pattern shows a regular change with the adjustment of the above vh1 and vh2, especially in the suppression of the back lobe level, which can be described as: as vh1 decreases, the front-to-back ratio of the pattern will increase accordingly. However, after exceeding a certain value, the front-to-back ratio will deteriorate in the opposite direction; as vh2 increases, the front-to-back ratio of the pattern will increase accordingly. Similarly, after exceeding a certain value, the front-to-back ratio will deteriorate in the opposite direction. The optimized limit values are vh1 = 20 mm and vh2 = 8 mm.

[0065] Assemble all the components, referring to Figure 1 As shown, it is a three-dimensional view of the miniaturized anti-jamming dual-frequency antenna carried by the UAV of the present invention.

[0066] Referring to Figure 13 As shown, it is the S-parameter simulation result of the miniaturized anti-jamming dual-frequency antenna carried by the present inventor's UAV. At 1.176 GHz and 1.575 GHz, both S11 and S22 are < -10 dB, indicating that the dual-frequency antenna has achieved good impedance matching in the L5 and L1 frequency bands.

[0067] To compare the influence of the sheet antenna assembly on the dual-frequency dual-feed antenna assembly, the radiation patterns of the dual-frequency dual-feed antenna assembly without and with the sheet antenna assembly loaded are given when excited at 1.176 GHz, and in the radiation pattern, all azimuth planes from Phi = 0° to 360° are observed, referring to Figures 14-15 As shown. When the sheet antenna assembly is not loaded, the main lobe gain of the antenna is 3.64 dBi, the front-to-back ratio is -7 dB, and the null depth is -5.2 dBi; when the sheet antenna assembly is loaded, the main lobe gain is 6.3 dBi, the front-to-back ratio is -26.3 dB, and the null depth is -92 dBi.

[0068] Similarly, the radiation pattern excited at 1.575 GHz is given, referring to Figures 16-17 As shown. When the sheet antenna assembly is not loaded, the peak gain of the antenna is 4.7213 dBi, the front-to-back ratio is -14 dB, and the null depth is -9.3 dBi; when the sheet antenna assembly is loaded, the main lobe gain is 6.93 dBi, the front-to-back ratio is -35.5 dB, and the null depth is -8.7 dBi.

[0069] The above are only the embodiments of the present invention and should not be construed as limiting the scope of the present invention. Those skilled in the art can modify, innovate, or apply the claims and the content of the drawings to other technical fields. However, it should be noted that all modifications to the present invention should be included within the scope of the patent protection of the present invention.

Claims

1. A miniaturized anti-interference dual-frequency antenna, characterized in that: include: A patch antenna assembly (1); A dual-frequency dual-feed antenna assembly (2), which is arranged below the sheet-shaped antenna assembly (1); the dual-frequency dual-feed antenna assembly (2) comprises a first antenna unit (21) and a second antenna unit (22) stacked together; A first ground plane (3), which is arranged below the dual-frequency dual-feed antenna assembly (2); A shielding cover (4) arranged below the first grounding plate (3); A second grounding plate (5) disposed below the shielding cover (4); The patch antenna assembly (1) comprises, from top to bottom, a plurality of patch antennas of the same shape and structure, wherein each patch antenna comprises a patch antenna dielectric layer and a metal layer arranged below the patch antenna dielectric layer, and a support column is arranged between each patch antenna; the centers of the patch antennas overlap.

2. The miniaturized anti-interference dual-frequency antenna according to claim 1, characterized in that: The first grounding plate (3) comprises a first grounding plate first metal layer (31), a first grounding plate dielectric layer (32) arranged below the first grounding plate first metal layer (31), and a first grounding plate second metal layer (33) arranged below the first grounding plate dielectric layer (32); an etched circuit (34) is engraved on the surface of the first grounding plate second metal layer (33); and the shielding cover (4) completely covers the dual-frequency dual-feed antenna assembly (2) and the etched circuit (34).

3. The miniaturized anti-interference dual-frequency antenna according to claim 2, characterized in that: The etching circuit (34) comprises a combiner circuit (345), a first resistor (343), a second resistor (344), a first hybrid coupler (341) and a second hybrid coupler (342); the combiner circuit (345) comprises a first port (3451), a second port (3453) and a third port (3455), wherein the first port (3451) and the second port (3453) are connected via a first microstrip line (3452), and the first port (3451) and the third port (3455) are connected via a second microstrip line (3454); one end of the first hybrid coupler (341) is connected to the second port (3453), and the other end is connected to the first resistor (343); one end of the second hybrid coupler (342) is connected to the third port (3455), and the other end is connected to the second resistor (344).

4. The miniaturized anti-interference dual-frequency antenna according to claim 3, characterized in that: The first antenna unit (21) comprises a first radiator (211), a first medium (212), a first coaxial probe (214) and a second coaxial probe (216); the first medium (212) and the first metal plate are both provided with a first through hole (213) and a second through hole (215); the first coaxial probe (214) passes through the first through hole (213) and the first grounding plate (3); the second coaxial probe (216) passes through the second through hole (215) and the first grounding plate (3); the first coaxial probe (214) and the second coaxial probe (216) respectively contact the first radiator (211) and the first hybrid coupler (341) at both ends; there is an air medium between the first coaxial probe (214) and the inner wall of the first through hole (213); there is an air medium between the second coaxial probe (216) and the inner wall of the second through hole (215).

5. The miniaturized anti-interference dual-frequency antenna according to claim 4, characterized in that: The second antenna unit (22) comprises a second radiator (221), a second medium (222), a third coaxial probe (224) and a fourth coaxial probe (226); the second medium (222) and the second metal plate are both provided with a third through hole (223) and a fourth through hole (225); the second radiator (221) and the second medium (222) are both provided with a fifth through hole (227) and a sixth through hole (228); the third coaxial probe (224) passes through the third through hole (223) and the first grounding plate (3); the fourth coaxial probe (226) passes through the fourth through hole (225) to and a first grounding plate (3); the third coaxial probe (224) and the fourth coaxial probe (226) realize contact between the second radiator (221) and the second hybrid coupler (342) at both ends respectively; there is an air medium between the third coaxial probe (224) and the inner wall of the third through hole (223); there is an air medium between the fourth coaxial probe (226) and the inner wall of the fourth through hole (225); there is an air medium between the first coaxial probe (214) and the inner wall of the fifth through hole (227); and there is an air medium between the second coaxial probe (216) and the inner wall of the sixth through hole (228).

6. The miniaturized anti-interference dual-frequency antenna according to claim 1, characterized in that: The shape of the patch antenna is rectangular, cross-shaped or circular.

7. The miniaturized anti-interference dual-frequency antenna according to claim 1, characterized in that: The operating frequency of the first antenna unit (21) and the second antenna unit (22) is L band.

8. The miniaturized anti-interference dual-frequency antenna according to claim 1, characterized in that: The second grounding plate (5) is provided with a metal column (51) for fixing the second grounding plate (5); the second grounding plate (5) is used to support the shielding cover (4); the diameter of the second grounding plate (5) is greater than the diameter of the shielding cover (4).

9. The miniaturized anti-interference dual-frequency antenna according to claim 5, characterized in that: The first medium (212) and the second medium (222) are made of ceramics, and each of the sheet antenna dielectric layers and the first ground plane dielectric layer (32) are made of FR4 board material.

10. Application of the miniaturized anti-interference dual-frequency antenna according to any one of claims 1 to 9 on a drone.

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