Small vivaldi antenna

Abstract

The utility model provides a miniature vivaldi antenna, which relates to the technical field of antennas and comprises a dielectric plate, an antenna unit and a supporting groove, the dielectric plate is a square plate, and one end of the dielectric plate is arranged in the supporting groove so as to support the dielectric plate through the supporting groove; an antenna unit is installed on at least one side surface of the dielectric plate, the antenna unit comprises a left arm and a right arm, the left arm and the right arm are symmetrically arranged on one side of the top of the dielectric plate, the adjacent ends of the left arm and the right arm extend downwards towards the sides close to each other to be provided with curved surface type connecting parts, and the two sets of connecting parts extend into the supporting grooves respectively and are coaxially arranged; two opposite ends of the left arm and the right arm respectively extend to be flush with the edge of the dielectric plate; the two opposite sides of the left arm and the right arm are respectively provided with a plurality of zigzag gaps which are uniformly arranged along the edges, and the zigzag gaps introduced by the left arm and the right arm of the antenna unit increase the current flow path on the surface of the antenna, equivalently increase the radiation area of the antenna, and effectively reduce the transverse physical size of the antenna.

Description

Technical Field

[0001] This utility model relates to the field of antenna technology, and more specifically, to a small Vivaldi antenna. Background Technology

[0002] The Vivaldi antenna (also known as a tapered slot antenna) is an ultra-wideband (UWB) directional radiating antenna based on an exponentially tapered slot structure, first proposed by Peter Gibson in 1979. Its core design utilizes an exponentially tapered slot width along the propagation direction to achieve a smooth transition from transmission line mode to free-space wave, thus maintaining stable radiation characteristics and impedance matching over an extremely wide bandwidth (up to 10:1 or higher). Vivaldi antennas are widely used in radar, electronic warfare, and wireless communication, and have received particular attention in phased array systems requiring wide bandwidth scanning.

[0003] Despite the significant advantages of Vivaldi antennas, they face the following bottlenecks in miniaturization and array applications: In space-constrained scenarios such as drones, wearable devices, and automotive radar, the lateral size of the antenna becomes a key limiting factor. Existing Vivaldi antennas have a large lateral size (≥0.5 times the low-frequency wavelength), making it difficult to meet the requirements for compact installation. On the other hand, to avoid grating lobes during array scanning, small-pitch arrays severely limit the scanning range of the array antenna. Utility Model Content

[0004] The purpose of this invention is to address the problems in the prior art by providing a small Vivaldi antenna. By introducing serrated gaps at the edges of the left and right arms of the antenna element, the current flow path on the antenna surface is increased, effectively increasing the antenna radiation area and reducing the lateral physical size of the antenna.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] This utility model provides a small Vivaldi antenna, including a dielectric substrate, an antenna element, and a support groove. The dielectric substrate is a square plate, and one end of the dielectric substrate is disposed in the support groove to support the dielectric substrate.

[0007] The antenna element is mounted on at least one side surface of the dielectric substrate. The antenna element includes a left arm and a right arm. The left arm and the right arm are symmetrically arranged on the top side of the dielectric substrate. The adjacent ends of the left arm and the right arm extend downward toward the side that is close to each other and are provided with curved connecting parts. The two sets of connecting parts extend into the support groove and are coaxially arranged. The opposite ends of the left arm and the right arm extend to be flush with the edge of the dielectric substrate.

[0008] The left and right arms each have several serrated slits evenly arranged along their edges on opposite sides.

[0009] Optionally, the contour curve equations of the connection between the right arm and the left arm are both exponential equations with varying parameters.

[0010] Optionally, a reflector is provided on the side of the support groove near the antenna unit, and the reflector is perpendicular to the dielectric plate;

[0011] Both the support groove and the reflector are metal plates.

[0012] Optionally, an antenna feed coaxial cable is provided on the side of the support groove away from the dielectric substrate. The antenna feed coaxial cable is located in the middle of the support groove and is connected to the connection parts of the left arm and the right arm respectively to provide a signal to the antenna.

[0013] Optionally, parasitic units are respectively provided on the side of the left arm and the right arm away from the support groove. The parasitic unit is a long strip slit provided on the antenna unit, and a plurality of absorption loads are provided in the long strip slit.

[0014] Optionally, the size of the absorbent load is the same as the width of the elongated slit.

[0015] Optionally, the dielectric substrate has a length of 160mm, a width of 145mm, and a thickness of 1mm.

[0016] This utility model provides a small Vivaldi antenna, including a dielectric substrate, an antenna element, and a support groove. The dielectric substrate is a square plate, with one end of the dielectric substrate disposed in the support groove to support the dielectric substrate. An antenna element is mounted on at least one side surface of the dielectric substrate. The antenna element includes a left arm and a right arm, which are symmetrically arranged on one side of the top of the dielectric substrate. Adjacent ends of the left and right arms extend downwards towards their respective adjacent sides, forming curved connecting portions. The two sets of connecting portions extend coaxially into the support groove. The opposing ends of the left and right arms extend to be flush with the edge of the dielectric substrate. The opposing sides of the left and right arms are respectively provided with… The antenna unit of this invention features several evenly arranged serrated slits along its edges. These serrated slits on the left and right arms increase the current flow path on the antenna surface, effectively increasing the antenna's radiation area and reducing its lateral physical dimensions. A slotted metal parasitic element at the end of the antenna unit introduces an absorbing load, which acts as a guide, improving the antenna's radiation directionality, increasing gain, and effectively widening the antenna's operating bandwidth. A metal reflector with a metal support groove below the antenna unit effectively reduces the antenna's back-radiated energy and increases gain. Optimizing the inner and outer contour curves of the left and right arms of the antenna unit results in a more balanced current distribution on the vibrator arms, achieving the goal of widening the bandwidth. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A schematic diagram of a small Vivaldi antenna provided in an embodiment of this application;

[0019] Figure 2 A top view of a small Vivaldi antenna provided for an embodiment of this application;

[0020] Figure 3 A front view of a small Vivaldi antenna provided for an embodiment of this application;

[0021] Figure 4 A rear view of a small Vivaldi antenna provided for an embodiment of this application;

[0022] Figure 5 A schematic diagram of the inner and outer contour curves of the left and right arms of a small Vivaldi antenna provided for an embodiment of this application;

[0023] Figure 6An antenna standing wave ratio (VSWR) curve of a small Vivaldi antenna provided for an embodiment of this application;

[0024] Figure 7 An antenna gain curve of a small Vivaldi antenna provided for embodiments of this application;

[0025] Figure 8 One of the antenna radiation patterns of a small Vivaldi antenna provided in this application embodiment;

[0026] Figure 9 This is a second example of an antenna radiation pattern for a small Vivaldi antenna provided in an embodiment of this application.

[0027] Figure 10 The third antenna radiation pattern of a small Vivaldi antenna provided in this application embodiment;

[0028] Figure 11 The fourth antenna radiation pattern of a small Vivaldi antenna provided in the embodiments of this application;

[0029] Figure 12 Fifth antenna radiation pattern of a small Vivaldi antenna provided in the embodiments of this application;

[0030] Figure 13 The sixth antenna radiation pattern of a small Vivaldi antenna provided in this application embodiment.

[0031] Icons: 10, dielectric substrate; 20, left arm; 21, right arm; 30, parasitic element; 31, absorbing load; 40, serrated slot; 50, support slot; 60, reflector; 70, antenna feed coaxial cable. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of this application. It should be noted that, without conflict, the various features in the embodiments of this application can be combined with each other, and the combined embodiments are still within the protection scope of this application.

[0033] Existing Vivaldi antennas have the following drawbacks: Their large lateral dimensions (≥0.5 times the low-frequency wavelength) make them unsuitable for applications with limited installation space, hindering small-pitch array deployment and severely limiting the array antenna scanning range (scaffold lobes cannot appear during scanning), thus preventing their application in wide-angle scanning antenna arrays; under a VSWR < 2.5, they can only achieve a 10:1 frequency harmonic operating bandwidth, making them unsuitable for ultra-wideband antennas requiring greater bandwidth; and when operating within the 10:1 frequency harmonic wideband, their low-frequency gain is low (0-2 dBi), failing to meet the requirements of long-distance special communication scenarios. To address these issues, this application provides a small Vivaldi antenna with the advantages of ultra-wideband high gain.

[0034] like Figure 1 , Figure 2 , Figure 3 , Figure 4 and Figure 5 As shown, Figure 1-5 This is a diagram of an antenna structure provided in an embodiment of this application. The embodiment provides a small Vivaldi antenna, including a dielectric substrate 10, antenna elements, and a support groove 50. The dielectric substrate 10 is a square plate, with one end disposed within the support groove 50 to support the dielectric substrate 10. At least one side surface of the dielectric substrate 10 is equipped with an antenna element, which includes a left arm 20 and a right arm 21. The left arm 20 and right arm 21 are symmetrically arranged on one side of the top of the dielectric substrate 10. Adjacent ends of the left arm 20 and right arm 21 extend downwards towards the side closest to each other, and curved connecting portions are provided. The two sets of connecting portions extend coaxially into the support groove 50. The opposite ends of the left arm 20 and right arm 21 extend to be flush with the edge of the dielectric substrate 10. Several evenly arranged serrated slits 40 are provided on the opposite sides of the left arm 20 and right arm 21.

[0035] Specifically, the contour curve equations of the connection between the right arm 21 and the left arm 20 are both exponential equations with varying parameters.

[0036] Specifically, a reflector 60 is provided on the side of the support groove 50 near the antenna element, and the reflector 60 is perpendicular to the dielectric plate 10; both the support groove 50 and the reflector 60 are metal plates.

[0037] Specifically, an antenna feed coaxial cable 70 is provided on the side of the support groove 50 away from the dielectric plate 10. The antenna feed coaxial cable 70 is located in the middle of the support groove 50 and is connected to the connection parts of the left arm 20 and the right arm 21 respectively to provide signals to the antenna.

[0038] Specifically, parasitic units 30 are respectively provided on the side of the left arm 20 and the right arm 21 away from the support groove 50. The parasitic unit 30 is a long strip slit provided on the antenna unit, and several absorption loads 31 are provided in the long strip slit.

[0039] Specifically, the width of the long strip slit is 2mm, and the size of the absorbent load 31 is the same as the width of the long strip slit. Three absorbent loads 31 are respectively set in the long strip slits of the left arm 20 and the right arm 21.

[0040] This application provides a small Vivaldi antenna, wherein the antenna dimensions (length × width × height) are 160mm × 145mm × 1mm, the antenna operating frequency band is 0.8GHz-18GHz (22.5:1 harmonics), and within the operating frequency band, the antenna VSWR < 2.0 and the antenna gain G > 4dBi. Figure 6 For antenna standing wave ratio (VSWR) < 2.0, Figure 7 This is a gain curve within the operating frequency band. Figure 8 , Figure 9 , Figure 10 , Figure 11 , Figure 12 and Figure 13 These are the antenna radiation patterns. Figure 8 Frequency 0.8GHz, Φ=90°; Figure 9 Frequency 0.8GHz, Φ=0°; Figure 10 Frequency 9.8GHz, Φ=90°; Figure 11 Frequency 9.8GHz, Φ=0°; Figure 12 Frequency 18GHz, Φ=90°; Figure 13 Frequency 18GHz, Φ=0°.

[0041] (1) To reduce the problem of the large lateral size of the existing Vivaldi antenna (≥0.5 times the low-frequency wavelength), serrated gaps 40 are introduced at the edges of the left and right arms of the antenna element. This increases the current flow path on the antenna surface, effectively increasing the antenna radiation area and reducing the lateral physical size of the antenna (the lateral size of the antenna is only 0.39 times the low-frequency wavelength); (2) To broaden the impedance bandwidth of the existing Vivaldi antenna, the inner and outer contour curves of the left and right arms of the antenna element are optimized. The equations for the inner and outer contour curves are as follows: By optimizing and adjusting the values ​​of the three parameters a1, a2, and a3 in the equation, the physical structure of the inner and outer contours of the left and right arms of the antenna is changed, thereby making the current distribution on the vibrator arm more balanced and achieving the purpose of widening the bandwidth; a 2mm gap is added at the end of the left and right arms of the antenna element, and 6 absorption loads 31 are added between the gaps. The current at the end of the antenna element is weak, and the working bandwidth of the antenna is effectively widened under the premise of minimal impact on the gain; (3) In order to solve the problem of low gain of the existing Vivaldi antenna, a metal parasitic unit 30 is introduced above the antenna element, which plays a guiding role in the antenna, improves the directivity of the antenna radiation, and increases the gain; a metal reflector 60 with a supporting metal groove is added below the antenna element, which can effectively reduce the back radiation energy of the antenna and increase the gain. Specifically, the dielectric substrate 10 has a length of 160mm, a width of 145mm, a thickness of 1mm, a working frequency band of 0.8GHz~18GHz, an antenna standing wave ratio (VSWR) of less than 2.0, and an antenna gain G greater than 4dBi.

[0042] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A small vivaldi antenna, comprising a dielectric plate (10), an antenna unit and a support groove (50), characterized in that: the dielectric plate (10) is a square plate, one end of the dielectric plate (10) is arranged in the support groove (50) to support the dielectric plate (10) through the support groove (50); at least one side surface of the dielectric plate (10) is mounted with the antenna unit, the antenna unit comprises left arms (20) and right arms (21), the left arms (20) and the right arms (21) are symmetrically arranged on one side of the top of the dielectric plate (10), the adjacent ends of the left arms (20) and the right arms (21) are provided with curved connecting parts which are arranged downwardly towards the side where the left arms (20) and the right arms (21) are close to each other, and the two groups of connecting parts are coaxially arranged in the support groove (50) respectively, the opposite ends of the left arms (20) and the right arms (21) are respectively extended to the edge of the dielectric plate (10); the opposite sides of the left arms (20) and the right arms (21) are respectively provided with a plurality of sawtooth-shaped slits (40) which are uniformly arranged along the edge.

2. The compact vivaldi antenna according to claim 1, wherein The profile curve equations of the connecting parts of the right arms (21) and the left arms (20) are both parameter-varying exponential equations.

3. The compact vivaldi antenna according to claim 1, wherein The side of the support groove (50) close to the antenna unit is provided with a reflecting plate (60), the reflecting plate (60) is perpendicular to the dielectric plate (10); The support groove (50) and the reflecting plate (60) are both metal plates.

4. The compact vivaldi antenna according to claim 1, wherein The side of the support groove (50) away from the dielectric plate (10) is provided with an antenna feed coaxial cable (70), the antenna feed coaxial cable (70) is located at the middle position of the support groove (50), the antenna feed coaxial cable (70) is connected to the connecting parts of the left arms (20) and the right arms (21) respectively, for providing signals for the antenna.

5. The compact vivaldi antenna according to claim 1, wherein The side of the left arms (20) and the right arms (21) away from the support groove (50) is respectively provided with a parasitic unit (30), the parasitic unit (30) is a long slit arranged on the antenna unit, a plurality of absorbing loads (31) are arranged in the long slit.

6. The compact Vivaldi antenna according to claim 5, characterized in that The size of the absorbing load (31) is the same as the width of the long slit.

7. The compact Vivaldi antenna according to claim 1, wherein The length of the dielectric plate (10) is 160 mm, the width is 145 mm, and the thickness is 1 mm.

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