Miniaturized antipodal vivaldi antenna based on special double-hole slot structure and design method

Abstract

The application discloses a miniaturized antipodal Vivaldi antenna based on a special double-hole slot structure and a design method, and belongs to the wireless communication field. The application solves the problem that the existing size optimization scheme cannot guarantee the antenna efficiency and gain performance simultaneously. The antenna is composed of a dielectric substrate, a top copper layer and a bottom copper layer. The top copper layer comprises a radiation arm and a feeding structure, and the end of the radiation arm is in a horn-shaped opening. The bottom copper layer is in a symmetrical structure with the top copper layer. The top and bottom copper layers are provided with an elliptical structure, a rectangular slot, a plurality of inclined rectangular slots and a parasitic patch structure. The elliptical structure is located in the middle of the radiation arm, the rectangular slot extends to the middle line of the antenna and separates the right copper layer of the elliptical structure, the inclined rectangular slots are distributed at the edge of the horn mouth and the open end faces the radiation direction. The parasitic patch structure is on both sides of the middle line of the antenna and forms a capacitive coupling. The antenna is applied to the fields of remote sensing detection, mobile communication and the like.

Description

Technical Field

[0001] This invention belongs to the field of wireless communication, and in particular relates to a miniaturized antipodal Vivaldi antenna based on a special dual-slot structure. Background Technology

[0002] In wireless communication systems, antennas are the core components for receiving and transmitting electromagnetic waves, and they have wide applications in civilian fields such as mobile communication, the Internet of Things (IoT), and vehicle communication. In recent years, with the rapid development of wireless communication technology and the increasing trend towards device miniaturization, the demand for efficient, wideband, and miniaturized antennas has been continuously growing. However, there is an inherent contradiction between antenna miniaturization and wideband characteristics in theory. According to the Chu / Wheeler theory, as antenna size decreases, its radiation efficiency and bandwidth performance typically decrease significantly. Achieving the optimal balance between size, bandwidth, and efficiency has become a significant challenge in the field of antenna design.

[0003] Currently, the classic antipodal Vivaldi antenna (AVA) is widely used due to its excellent performance, typically with a wide bandwidth of 90%-150% and high gain. However, its large size results in significant shortcomings in integration. Traditional miniaturization methods include loading techniques, meandering techniques, and the use of high-dielectric-constant substrates. While these methods have optimized antenna performance to some extent, they have also introduced new problems. For example, the complex structure of loading techniques increases manufacturing difficulty; while meandering techniques lengthen the current path, they negatively impact the radiation pattern; and although high-dielectric-constant substrates can reduce size, their high cost limits their widespread adoption in practical applications.

[0004] Furthermore, classic AVAs face several technical limitations during miniaturization. First, existing size optimization schemes fail to fully utilize the redesign of the current path, making it difficult to further reduce size while maintaining broadband characteristics. Second, antenna efficiency and gain performance are not effectively guaranteed during miniaturization, and performance degradation is easily caused by design limitations. Finally, traditional solutions also fall short in improving integration and application flexibility, making it difficult to fully meet the demands of modern wireless communication devices for compact structures and high performance. Summary of the Invention

[0005] In view of this, the present invention aims to propose a miniaturized antipodal Vivaldi antenna based on a special dual-slot structure, in order to solve the problem that existing size optimization schemes cannot simultaneously guarantee antenna efficiency and gain performance.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a miniaturized antipodal Vivaldi antenna based on a special dual-slot structure, the antenna comprising: A dielectric substrate and a bimetallic layer, the bimetallic layer comprising a top copper layer and a bottom copper layer; The top copper layer is disposed on the upper surface of the dielectric substrate and includes a radiating arm and a feeding structure, wherein the end of the radiating arm forms a horn-shaped opening; The bottom copper layer is disposed on the lower surface of the dielectric substrate and has an antipodal symmetrical structure with the top copper layer; The top copper layer and the bottom copper layer are respectively provided with: The structure comprises a first elliptical structure, a second elliptical structure, a first rectangular groove, a second rectangular groove, multiple inclined rectangular grooves, and a parasitic patch structure. Both the first elliptical structure and the second elliptical structure are located in the middle of the radiating arm, and the major semi-axis of the first elliptical structure is parallel to the antenna radiation direction. The first rectangular slot and the second rectangular slot extend through the central axis of the corresponding elliptical structure to the antenna centerline, separating the copper layer on the right side of the elliptical structure. The plurality of inclined rectangular slots are evenly distributed at intervals along the edge of the trumpet-shaped opening, with the open end of each inclined rectangular slot facing the radial direction; The parasitic patch structure is symmetrically arranged on both sides of the antenna centerline, forming a capacitive coupling structure with the adjacent copper layer.

[0007] Furthermore, a preferred embodiment is proposed in which the dielectric substrate is made of FR-4 material with a thickness of 1.93±0.1mm and a dielectric constant of 4.8±0.2.

[0008] Furthermore, a preferred embodiment is proposed, wherein the ratio of the length of the major semi-axis to the minor semi-axis of the first elliptical structure and the second elliptical structure is 1.5:1 to 3:1, and the distance from the center of the ellipse to the antenna feed point is 1 / 4 to 1 / 3 of the total length of the antenna.

[0009] Furthermore, a preferred embodiment is proposed, wherein the width of the first rectangular slot and the second rectangular slot is 0.2-0.5 mm, and the length direction forms an angle of 15°-45° with the antenna centerline.

[0010] Furthermore, a preferred embodiment is proposed, wherein the number of inclined rectangular grooves is four, each groove having an equal length and forming an inclination angle of 30°-60° with the radial direction, and the length of the groove is 1 / 5 to 1 / 3 of the width of the horn opening.

[0011] Furthermore, a preferred embodiment is proposed, wherein the parasitic patch structure is a symmetrically distributed metal sheet with a spacing of 0.1-0.3 mm from the adjacent copper layer, and the patch area is 10%-25% of the copper layer area in the corresponding region.

[0012] Furthermore, a preferred embodiment is proposed in which an opening is provided at the bottom of the inner arc of the antenna.

[0013] Based on the same inventive concept, this invention also proposes a miniaturization design method for a Vivaldi antenna, the method comprising: Step S1: Construct top and bottom copper layers with antipodal symmetry, and form radiating arms and feeding structures on the upper and lower surfaces of the dielectric substrate, respectively. Process horn-shaped openings at the ends of the radiating arms. Step S2: Fabricate an elliptical structure in the middle of the radiating arm, with its major semi-axis parallel to the radiation direction, and the distance from the center of the ellipse to the feed structure being 25%-35% of the total antenna length; Step S3: Cut a rectangular slot so that one end of the slot passes through the center of the ellipse and the other end extends to the central axis of the antenna. The direction of the slot forms an angle of 15°-45° with the central axis, separating the copper layer on the right side of the ellipse. Step S4: Machin four inclined rectangular grooves at the edge of the trumpet-shaped opening, with an inclination angle of 30°-60°. The grooves are open at the left end and closed at the right end, and their length is set to 1 / 5 to 1 / 3 of the width of the trumpet opening. Step S5: Add symmetrical parasitic patches with a spacing of 0.1-0.3 mm between them and the adjacent copper layer to form a capacitive coupling structure, and adjust the patch area to 10%-25% of the copper layer area in the corresponding region.

[0014] Furthermore, a preferred embodiment is proposed, wherein the ratio of the length of the major semi-axis to the minor semi-axis of the elliptical structure in step S2 is 1.5:1 to 3:1, and the width of the rectangular groove in step S3 is 0.2-0.5 mm, and the length is equal to 1.2-1.5 times the length of the major semi-axis of the ellipse.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. The miniaturized antipodal Vivaldi antenna proposed in this invention, through the coordinated design of an elliptical structure, dual rectangular slots, and tilted slots, reduces the antenna size to 0.498 times the length and 0.486 times the width of the classic AVA while maintaining the wideband characteristics of the antipodal Vivaldi antenna (AVA), and its area is only 0.242 times that of the classic antenna. This design overcomes the application limitations caused by the excessive size of traditional AVAs, allowing it to be integrated into compact devices such as miniaturized radar modules and portable communication terminals.

[0016] 2. The miniaturized anti-podomorphic Vivaldi antenna proposed in this invention achieves an impedance bandwidth >90% and a voltage standing wave ratio (VSWR) ≤2.5 in the 0.72-2GHz frequency band. Furthermore, its gain in the high-frequency band (1.3-2GHz) is 0.5-1.2dB higher than the classic AVA, solving the problems of narrowed bandwidth and decreased gain in traditional miniaturization schemes. Through the capacitive coupling design of the parasitic patch, the input impedance fluctuation range within the operating frequency band is ≤15Ω, and the reflection coefficient is ≤-10dB, significantly improving signal transmission efficiency.

[0017] 3. The introduction of the tilted rectangular slot in the miniaturized antipodal Vivaldi antenna proposed in this invention effectively suppresses the sidelobe level. At 1.5 GHz and 2 GHz frequencies, the main lobe width of the radiation pattern is reduced by 10%-20% compared to the classic AVA, and the sidelobe level is reduced by 3-5 dB. This optimization enables the antenna to have higher target resolution and anti-interference capability in radar detection and directional communication scenarios.

[0018] 4. The miniaturized antipodal Vivaldi antenna proposed in this invention uses an FR-4 substrate with a dielectric constant of 4.8, costing only 1 / 3 to 1 / 5 of high-dielectric-constant substrates. Combined with a single-layer double-sided etching process, it avoids the processing requirements of multi-layer composite structures or special materials in traditional solutions. The design parameters of the rectangular slot and parasitic patches, such as slot width 0.2-0.5mm and patch spacing 0.1-0.3mm, are compatible with standard PCB processes, improving the yield rate by 15%-20%.

[0019] 5. The combination of elliptical structure and rectangular slot in the miniaturized antipodal Vivaldi antenna proposed in this invention extends the main path of surface current by 1.2-1.8 times, reduces the lowest resonant frequency of the antenna, and expands the low-frequency bandwidth. At the same time, the tilted slot reconstructs the current distribution in the horn region, suppresses the edge diffraction effect in the high-frequency band, and makes the gain curve flatter in a wide frequency band with a fluctuation range of ≤1dB.

[0020] 6. The miniaturized antipodal Vivaldi antenna proposed in this invention is compatible with ultra-wideband (UWB) communication, 77GHz front-end frequency band adaptation for vehicle radar, electronic countermeasures systems, and other scenarios. The measured directivity coefficient at 1.5GHz reaches 8.5dBi, which can replace traditional horn antennas and reduce system size and power consumption. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of a miniaturized antipodal Vivaldi antenna structure based on a special double-slot structure, as described in this embodiment of the present invention. Figure 2 This is a schematic diagram of the optimized path for the miniaturized AVA described in this invention; Figure 3 This is a comparison chart of the s-parameters of the miniaturized and unoptimized AVA described in this invention; Figure 4 This is a size comparison diagram of the classic antipodal Vivaldi antenna and the miniaturized antipodal Vivaldi antenna described in this invention; Figure 5This is a comparison chart of the maximum gain of the classic AVA and the miniaturized AVA described in this invention; Figure 6 This is a comparison of the radiation patterns of the classic AVA and the miniaturized AVA described in this invention at three frequencies: 1, 1.5, and 2 GHz. Figure 7 This is a disassembly diagram of a miniaturized antipodal Vivaldi antenna structure based on a special double-slot structure, as described in this invention. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other, and the described embodiments are only some embodiments of the present invention, not all embodiments.

[0023] Implementation Method 1, see Figure 1 This embodiment describes a miniaturized antipodal Vivaldi antenna based on a special dual-slot structure. The antenna includes: Dielectric substrate 1 and a double metal layer, the double metal layer comprising a top copper layer 2 and a bottom copper layer 3; The top copper layer 2 is disposed on the upper surface of the dielectric substrate and includes a radiating arm and a feeding structure. The end of the radiating arm forms a horn-shaped opening. The bottom copper layer 3 is disposed on the lower surface of the dielectric substrate and has an antipodal symmetrical structure with the top copper layer; The top copper layer 2 and the bottom copper layer 3 are respectively provided with: 4. First elliptical structure; 5. Second elliptical structure; 6. First rectangular groove; 7. Second rectangular groove; 8. Multiple inclined rectangular grooves; and 9. Parasitic patch structure. The first elliptical structure 4 and the second elliptical structure 5 are both located in the middle of the radiating arm, and the major semi-axis of the first elliptical structure is parallel to the antenna radiation direction. The first rectangular slot 6 and the second rectangular slot 7 extend through the central axis of the corresponding elliptical structure to the antenna centerline, separating the copper layer on the right side of the elliptical structure. The plurality of inclined rectangular slots 8 are evenly distributed at intervals on the edge of the trumpet-shaped opening, with the open end of each inclined rectangular slot facing the radial direction; The parasitic patch structure 9 is symmetrically arranged on both sides of the antenna centerline, forming a capacitive coupling structure with the adjacent copper layer.

[0024] This embodiment effectively alters the current flow direction by introducing stripes and elliptical or circular structures along the main current path on the antenna surface. This causes the current path to bend and increase its length, thereby enhancing the antenna's radiation efficiency and gain. Simultaneously, a parasitic patch is added to the upper part of the antenna, opposite the main current path, to improve input impedance matching over a wide bandwidth, reduce reflection loss, and increase transmission efficiency. These design innovations not only achieve antenna miniaturization but also ensure that its ultra-wideband characteristics are preserved, ultimately optimizing its size without compromising its broadband performance.

[0025] Furthermore, multiple tilted rectangular stripes were introduced into the antenna horn region, effectively reducing the current distribution in this area. These stripe structures played a crucial role in improving the antenna's main lobe gain and reducing sidelobe radiation, while also further improving the radiation pattern performance, thus meeting the practical requirements for high-gain broadband antennas.

[0026] Implementation Method 2: This implementation method further defines the miniaturized antipodal Vivaldi antenna based on a special double-slot structure described in Implementation Method 1. The dielectric substrate 1 is made of FR-4 material with a thickness of 1.93±0.1mm and a dielectric constant of 4.8±0.2.

[0027] Implementation Method 3: This implementation method further defines the miniaturized antipodal Vivaldi antenna based on a special double-slot structure described in Implementation Method 1. The ratio of the length of the major semi-axis to the minor semi-axis of the first elliptical structure 4 and the second elliptical structure 5 is 1.5:1 to 3:1, and the distance from the center of the ellipse to the antenna feed point is 1 / 4 to 1 / 3 of the total length of the antenna.

[0028] In this embodiment, the ratio of the major to minor semi-axis of the first and second elliptical structures is between 1.5:1 and 3:1, which helps optimize the antenna's radiation mode and bandwidth. Simultaneously, the adjustment of the ratio of the major to minor semi-axis allows the elliptical structure to better match the radiation mode and feed structure, thereby improving the antenna's gain and radiation efficiency. Especially in high-frequency applications, the elliptical ratio design in this embodiment can reduce signal loss and improve the overall performance of the antenna.

[0029] Implementation Method 4: This implementation method further defines the miniaturized antipodal Vivaldi antenna based on a special double-slot structure described in Implementation Method 1. The width of the first rectangular slot 6 and the second rectangular slot 7 is 0.2-0.5 mm, and the length direction forms an angle of 15°-45° with the antenna centerline.

[0030] In this embodiment, by precisely adjusting the width, length, and angle with the antenna centerline of the first and second rectangular slots, the overall antenna structure can be made more compact, making it suitable for applications with limited space. Simultaneously, the dual-slot design further optimizes the antenna's radiation characteristics and impedance matching, reducing reflection loss. This means improved energy transmission efficiency and signal quality.

[0031] Implementation Method 5: This implementation method further defines the miniaturized antipodal Vivaldi antenna based on a special double-slot structure described in Implementation Method 1. The number of inclined rectangular slots 8 is 4, each slot has an equal length and forms an inclination angle of 30°-60° with the radiation direction, and the length of the slot is 1 / 5 to 1 / 3 of the horn opening width.

[0032] The tilted rectangular slot design in this embodiment effectively improves the antenna's radiation characteristics, especially in broadband applications. The tilted slot arrangement better disperses radiated energy, expands the antenna's operating bandwidth, and thus enhances its frequency response range, adapting to more complex and diverse communication needs. The tilt angle optimizes the antenna's radiation directivity, improving radiation efficiency and increasing antenna gain. Particularly when the tilt angle is between 30° and 60° with respect to the radiation direction, the radiation pattern can be precisely controlled, thereby improving the antenna's directivity and adapting to applications requiring strong directivity or wider coverage.

[0033] Despite incorporating four angled rectangular slots, the design maintains the antenna's miniaturization. The ratio of slot length to horn opening width is set to 1 / 5 to 1 / 3, helping to keep the antenna's compact structure without sacrificing performance. This allows the antenna to provide good radiation performance even in space-constrained environments, making it suitable for space-critical applications such as modern mobile communication devices and portable devices.

[0034] Implementation Method Six: This implementation method is a further refinement of the miniaturized antipodal Vivaldi antenna based on a special dual-slot structure described in Implementation Method One. The parasitic patch structure 9 is a symmetrically distributed metal sheet with a spacing of 0.1-0.3 mm from the adjacent copper layer, and the patch area is 10%-25% of the copper layer area in the corresponding region.

[0035] In this embodiment, the parasitic patch structure employs symmetrically distributed metal sheets, which helps improve the antenna's radiation efficiency and directivity. The symmetrical design ensures a more uniform radiation field distribution, thereby improving the overall antenna performance. The spacing between the metal sheet and the adjacent copper layer is 0.1-0.3 mm, and the patch area occupies 10%-25% of the corresponding copper layer area. This range effectively balances the antenna's bandwidth, gain, and directivity. Optimized spacing and patch area enhance the antenna's frequency response, increase operating bandwidth, and adapt to a wider range of frequency bands.

[0036] Employing a special dual-slot structure and parasitic patch design helps suppress unwanted reflections and interference, improving the antenna's anti-interference performance, making it particularly suitable for communication applications in complex environments. This design, through rationally distributed parasitic patches and an optimized structure, enhances the antenna's radiation efficiency, thereby increasing gain and ensuring signal transmission stability and coverage.

[0037] Implementation Method Seven: This implementation method is a further refinement of the miniaturized antipodal Vivaldi antenna based on a special double-slot structure described in Implementation Method One, wherein the antenna has an opening at the bottom of its inner arc.

[0038] Implementation Method 8: A miniaturization design method for a Vivaldi antenna described in this implementation method, the method comprising: Step S1: Construct top and bottom copper layers with antipodal symmetry, and form radiating arms and feeding structures on the upper and lower surfaces of dielectric substrate 1, respectively. A horn-shaped opening is processed at the end of the radiating arm. Step S2: Fabricate an elliptical structure in the middle of the radiating arm, with its major semi-axis parallel to the radiation direction, and the distance from the center of the ellipse to the feed structure being 25%-35% of the total antenna length; Step S3: Cut a rectangular slot so that one end of the slot passes through the center of the ellipse and the other end extends to the central axis of the antenna. The direction of the slot forms an angle of 15°-45° with the central axis, separating the copper layer on the right side of the ellipse. Step S4: Machin four inclined rectangular grooves at the edge of the trumpet-shaped opening, with an inclination angle of 30°-60°. The grooves are open at the left end and closed at the right end, and their length is set to 1 / 5 to 1 / 3 of the width of the trumpet opening. Step S5: Add symmetrical parasitic patches with a spacing of 0.1-0.3 mm between them and the adjacent copper layer to form a capacitive coupling structure, and adjust the patch area to 10%-25% of the copper layer area in the corresponding region.

[0039] Implementation Method Nine: This implementation method further defines the miniaturization design method of the Vivaldi antenna described in Implementation Method Eight. In step S2, the ratio of the length of the major semi-axis to the minor semi-axis of the elliptical structure is 1.5:1 to 3:1, and in step S3, the width of the rectangular slot is 0.2-0.5 mm, and the length is equal to 1.2-1.5 times the length of the major semi-axis of the ellipse.

[0040] Implementation Method 10, see below Figures 1 to 7 This embodiment describes a specific example of a miniaturized antipodal Vivaldi antenna based on a special dual-slot structure as described in Embodiment 1. It also serves to explain Embodiments 2 through 7. Specifically: The geometry and dimensions of the miniaturized antipodal Vivaldi antenna are as follows: Figure 1 and Figure 7 As shown, it consists of a single dielectric substrate layer and a bimetallic layer. The dielectric substrate is made of FR-4 material with a thickness of 1.93 mm and a dielectric constant of 4.8. The remaining structural material is pure copper with a tin-plated surface. In the figure, gold represents the top copper layer, light yellow represents the bottom copper layer, and green represents the substrate. This embodiment optimizes antenna performance through aperture, slots, and parasitic structures. Specifically, one end of the rectangular slot is located at the center of the elliptical structure, while the other end is aligned with the central axis of the antenna, thus separating the copper layer on the right side of the ellipse. A symmetrical configuration is applied near the feed line on the inner side of the antenna. In addition, four equidistantly inclined rectangular slots are provided at the flare of the AVA. Finally, patch structures are symmetrically added on opposite sides of the antenna to form capacitive coupling with the copper layers on the adjacent sides. This capacitive coupling mechanism effectively optimizes the input impedance of the antenna, ensuring impedance matching throughout the entire operating bandwidth.

[0041] Perform the following on unoptimized AVA: Figure 2 The four-step processing shown includes: adding an interconnected elliptical structure and a rectangular stripe structure to the upper part of the AVA, with one endpoint of the rectangular stripe at the center of the ellipse and the other endpoint at the antenna centerline, so that the stripe separates the copper layer on the right side of the ellipse; similarly, the inner arc of the antenna is the main path of the surface current, and openings are made in the main current path to make it have a meandering effect, which lowers the minimum frequency of the antenna and increases the bandwidth; adding four slanted rectangular stripes of equal length at the horn of the AVA, with the left end of the stripe being continuous and the right end being incomplete, the slanted rectangular stripes increase the main lobe and reduce the side lobes, thereby increasing the antenna gain; the parasitic structure, by forming a capacitor structure with the copper layer on the other side, improves the input impedance of the antenna, making the impedance matching of the antenna more stable in the operating frequency band and increasing the gain.

[0042] The redesigned miniaturized AVA and the classic AVA size for the same frequency band are compared as follows: Figure 3As shown, the miniaturized antenna size is reduced to 0.498 and 0.486 of the classic AVA, and the area is reduced to 0.242 of the classic AVA. Specifically, W1 (width of the classic Vivaldi antenna topology) is 223.89 mm, W2 (width of the miniaturized Vivaldi antenna topology) is 111.6 mm, L1 (length of the classic Vivaldi antenna topology) is 332.1 mm, and L2 (length of the miniaturized Vivaldi antenna topology) is 156.82 mm.

[0043] In summary, this invention achieves miniaturization of the AVA antenna. By incorporating slot and parasitic structures, a miniaturized AVA antenna suitable for a bandwidth of 0.73~2GHz is constructed. The antenna size is reduced to 0.498 and 0.486 of the classic antenna, and the area is reduced to 0.242 of the classic antenna.

[0044] Maximum gain comparison between classic AVA and miniaturized AVA Figure 5 As shown, the classic AVA has a greater gain in the range of 0.73-1.3GHz, but after 1.3-2GHz, the maximum gain of the miniaturized AVA is greater than that of the classic AVA. Figure 6 A comparison of the radiation patterns of the classic AVA and the miniaturized AVA at three frequencies of 1, 1.5, and 2 GHz shows that the classic AVA has better directivity than the miniaturized AVA at 1 GHz, while the miniaturized AVA has better directivity than the classic AVA at 1.5 and 2 GHz.

[0045] In summary, this antenna features a compact structure, small size, large bandwidth, good directivity, low cost, wide applicability, and easy integration, making it suitable for applications in remote sensing, mobile communications, and other fields.

[0046] The specific embodiments of the present invention disclosed above are merely illustrative of the invention. These embodiments do not exhaustively describe all details, nor do they limit the invention to the specific embodiments described. Many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention.

Claims

1. A miniaturized antipodal Vivaldi antenna based on a special dual-slot structure, characterized in that, The antenna includes: A dielectric substrate (1) and a bimetallic layer, the bimetallic layer comprising a top copper layer (2) and a bottom copper layer (3). The top copper layer (2) is disposed on the upper surface of the dielectric substrate and includes a radiating arm and a power feeding structure, wherein the end of the radiating arm forms a horn-shaped opening; The bottom copper layer (3) is disposed on the lower surface of the dielectric substrate and has an antipodal symmetrical structure with the top copper layer; The top copper layer (2) and the bottom copper layer (3) are respectively provided with: The structure consists of a first elliptical structure (4), a second elliptical structure (5), a first rectangular groove (6), a second rectangular groove (7), multiple inclined rectangular grooves (8), and a parasitic patch structure (9). The first elliptical structure (4) and the second elliptical structure (5) are both located in the middle of the radiating arm, and the major semi-axis of the first elliptical structure is parallel to the antenna radiation direction. The first rectangular slot (6) and the second rectangular slot (7) extend through the central axis of the corresponding elliptical structure to the antenna centerline, separating the copper layer on the right side of the elliptical structure. The plurality of inclined rectangular grooves (8) are evenly distributed at the edge of the trumpet-shaped opening, with the open end of each inclined rectangular groove facing the radial direction; The parasitic patch structure (9) is symmetrically arranged on both sides of the antenna centerline, forming a capacitive coupling structure with the adjacent copper layer.

2. The miniaturized antipodal Vivaldi antenna based on a special dual-slot structure according to claim 1, characterized in that, The dielectric substrate (1) is made of FR-4 material with a thickness of 1.93±0.1mm and a dielectric constant of 4.8±0.

2.

3. A miniaturized antipodal Vivaldi antenna based on a special dual-slot structure according to claim 1, characterized in that, The ratio of the length of the major semi-axis to the minor semi-axis of the first elliptical structure (4) and the second elliptical structure (5) is 1.5:1 to 3:1, and the distance from the center of the ellipse to the antenna feed point is 1 / 4 to 1 / 3 of the total length of the antenna.

4. A miniaturized antipodal Vivaldi antenna based on a special dual-slot structure according to claim 1, characterized in that, The width of the first rectangular slot (6) and the second rectangular slot (7) is 0.2-0.5mm, and the length direction forms an angle of 15°-45° with the antenna centerline.

5. A miniaturized antipodal Vivaldi antenna based on a special dual-slot structure according to claim 1, characterized in that, The number of inclined rectangular grooves (8) is 4, each groove has an equal length and forms an inclination angle of 30°-60° with the radial direction, and the length of the groove is 1 / 5 to 1 / 3 of the width of the horn opening.

6. A miniaturized antipodal Vivaldi antenna based on a special dual-slot structure according to claim 1, characterized in that, The parasitic patch structure (9) is a symmetrically distributed metal sheet with a spacing of 0.1-0.3 mm from the adjacent copper layer, and the patch area is 10%-25% of the copper layer area in the corresponding region.

7. A miniaturized antipodal Vivaldi antenna based on a special dual-slot structure according to claim 1, characterized in that, The antenna has an opening at the bottom of its inner arc.

8. A method for miniaturizing a Vivaldi antenna, characterized in that, The method is used to implement the miniaturized antipodal Vivaldi antenna of claim 1, and the method includes: Step S1: Construct top and bottom copper layers with antipodal symmetry, and form radiating arms and feeding structures on the upper and lower surfaces of the dielectric substrate (1), respectively. The ends of the radiating arms are processed with horn-shaped openings. Step S2: Fabricate an elliptical structure in the middle of the radiating arm, with its major semi-axis parallel to the radiation direction, and the distance from the center of the ellipse to the feed structure being 25%-35% of the total antenna length; Step S3: Cut a rectangular slot so that one end of the slot passes through the center of the ellipse and the other end extends to the central axis of the antenna. The direction of the slot forms an angle of 15°-45° with the central axis, separating the copper layer on the right side of the ellipse. Step S4: Machin four inclined rectangular grooves at the edge of the trumpet-shaped opening, with an inclination angle of 30°-60°. The grooves are open at the left end and closed at the right end, and their length is set to 1 / 5 to 1 / 3 of the width of the trumpet opening. Step S5: Add symmetrical parasitic patches with a spacing of 0.1-0.3mm between them and the adjacent copper layer to form a capacitive coupling structure, and adjust the patch area to 10%-25% of the copper layer area in the corresponding region.

9. A miniaturized design method for a Vivaldi antenna according to claim 8, characterized in that, In step S2, the ratio of the length of the major semi-axis to the minor semi-axis of the elliptical structure is 1.5:1 to 3:1, and in step S3, the width of the rectangular groove is 0.2-0.5 mm, and the length is equal to 1.2-1.5 times the length of the major semi-axis of the ellipse.

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