Ultra-wideband miniaturized vivaldi antenna

Abstract

The application belongs to the technical field of communication, and particularly relates to a kind of miniaturized Vivaldi antenna of ultra-wideband.The antenna contains a dielectric substrate, the upper surface of which contains an exponential tapered slot main Vivaldi antenna, four resistors and two rectangular metal patches, artificial surface plasmon;The lower surface is a feed network, containing 6 sections of impedance transformation microstrip transmission line, sector transmission line and circular slot;The main antenna is placed in the center of the dielectric substrate, the four resistors are placed at the end of the main antenna, and the resistors are connected to the two rectangular patches behind;Artificial surface plasmon is placed in the middle of the main antenna's tapered slot;The multi-section impedance transformer of the feed network and the microstrip slot line structure are placed in alignment with the circular slot of the main antenna.The application realizes ultra-wideband, miniaturization and high radiation gain through the design of the main antenna, edge slotting, resistor loading and artificial surface plasmon.The antenna's operating frequency band is 0.2 GHz to 18 GHz, and it has the characteristics of miniaturization.

Description

Technical Field

[0001] This invention belongs to the field of communication technology, specifically relating to an ultra-wideband miniaturized Vivaldi antenna. Background Technology

[0002] With the development of wireless communication technology, high-performance wireless communication receivers have attracted widespread attention and have significant applications in both civilian and military fields. Integrated reconnaissance, jamming, detection, and communication receivers, due to their small size, high flexibility, and powerful functions, represent the inevitable trend in future receiver development. Integrated radar receivers, in particular, require a very wide receiving bandwidth to acquire signals at various frequencies, while also being miniaturized to increase the difficulty of detection and maintain excellent mobility. This places high demands on the receiving antenna.

[0003] In recent years, researchers have designed various types of antennas, which can be classified according to their frequency band characteristics into narrowband antennas, wideband antennas, and ultra-wideband antennas; according to their radiation performance into omnidirectional and directional antennas; and according to the polarization of the electromagnetic waves they can collect into linearly polarized, dual-linearly polarized, circularly polarized, and dual-circularly polarized antennas. The Vivaldi antenna is an exponential taper antenna, belonging to the category of ultra-wideband antennas. It possesses excellent radiation performance, such as a wide bandwidth, symmetrical radiation pattern, and stable gain. Furthermore, the antenna itself has a simple structure, low manufacturing cost, and is easy to integrate, and is currently widely used in satellite communications, radar systems, electronic countermeasures, and wireless communications. Summary of the Invention

[0004] The purpose of this invention is to provide an ultrawideband miniaturized Vivaldi antenna capable of collecting frequencies from 0.2 GHz to 18 GHz in the environment.

[0005] The ultra-wideband miniaturized Vivaldi antenna provided by this invention can cover the 0.2GHz to 18GHz frequency band at 90 octaves, and has the characteristics of ultra-wideband and miniaturization.

[0006] The ultra-wideband miniaturized Vivaldi antenna provided by this invention has the following structure: Figure 1As shown, the device includes a dielectric substrate 11. The upper surface of the substrate contains a Vivaldi antenna (specifically a gradient slot metal patch) 1 with an exponentially tapered slot, four resistors 9-12, two rectangular metal patches 7, and an artificial surface plasmonic device 8. The lower surface of the substrate is a feed network, which includes a 6-section impedance transformation microstrip transmission line (called a 6-section impedance transformer) 2, a fan-shaped microstrip line 3, and a circular slot 4. The Vivaldi antenna 1 is centered and aligned with the dielectric substrate 13. The four resistors 9-12 are placed at the ends of the Vivaldi antenna 1, and the resistors are connected to the two rectangular patches 7. The artificial surface plasmonic device 8 is placed in the middle of the gradient slot of the Vivaldi antenna 1. The multi-section impedance transformer and microstrip slot line structure of the feed network are aligned with the circular slot of the Vivaldi antenna.

[0007] Among them, the antenna, the artificial surface plasma 8, and the bottom feeding network are respectively in close contact with the upper and lower surfaces of the dielectric substrate 13, with no gap between them;

[0008] The gradient groove metal patch 1 in the upper antenna is aligned with the bottom of the dielectric substrate 13, and three grooves are formed at the center of the gradient groove metal patch 1: a circular groove 4, a rectangular groove 5, and an exponential gradient groove 6, which are connected sequentially from bottom to top; two symmetrical rectangular grooves 14 are formed at the edge; two resistors 11-12 are connected to the rear end of the gradient groove metal patch 1, and two resistors 9-10 are connected to the end; a rectangular metal patch 7 is connected after the resistors 9-10; the gradient groove metal patch 1 and the rectangular metal patch 7 are aligned with the left and right sides of the dielectric substrate 13; see [reference] Figure 2 .

[0009] In the lower-layer feed network, the first microstrip line of the six impedance transformation microstrip lines 2 is aligned with the bottom of the dielectric substrate 13, and each impedance transformation microstrip line is connected end to end; the third microstrip line is designed with a right-angle bend; the last microstrip line is connected to the fan-shaped microstrip line 3, and its end is aligned with the edge of the rectangular slot; see [link to relevant documentation]. Figure 3 .

[0010] The artificial surface plasma is located at the center of the rear end of the gradient groove; see [link / reference]. Figure 2 Artificial surface plasma 8 has an I-shaped unit structure, which is composed of periodically extended I-shaped units.

[0011] In the feed network, six impedance transformers are designed to achieve impedance transformation from 50Ω to 100Ω, improve antenna impedance matching, and reduce losses. A fan-shaped microstrip line is added after the impedance transformer, and a circular slot 4 is added after the rectangular slot, so that the ends of the slot line and the microstrip line resonate, realizing the connection of the impedance discontinuity from the microstrip line to the slot line, and achieving wideband within the target bandwidth.

[0012] To achieve broadband matching, an exponentially gradient groove is designed on the gradient groove metal patch 1 for radiation; symmetrical rectangular grooves 14 are opened on the edge of the gradient groove metal patch 1 to extend the surface current path, reduce the resonant frequency, and achieve the purpose of expanding the low-frequency bandwidth and improving the impedance matching of the low-frequency band; lossy resistors 9-12 are added at the end of the gradient groove metal patch 1 to absorb the end current, thereby reducing the reflection coefficient of the low-frequency band, improving the impedance matching of the entire frequency band, and achieving the purpose of miniaturization.

[0013] Artificial surface plasma 8 is added in the middle of the gradient groove metal patch 1 to improve the radiation gain in the high frequency band.

[0014] In this invention, the dielectric substrate 13 is made of FR4 material with a dielectric constant of 4.4, a loss tangent of 0.015, and a thickness of 0.8 mm. The metal layer material is copper with a thickness of 0.035 mm.

[0015] In this invention, the resistance of the four resistors (9-12) is 100Ω;

[0016] This invention relates to an ultra-wideband miniaturized Vivaldi antenna operating in the 0.2 GHz to 18 GHz frequency band. Its dimensions are 308 × 180 × 0.8 mm. 3 (Length × Width × Height), i.e., 0.16λ0 × 0.28λ0 mm 2 (Length × Width), where λ0 is the free space wavelength corresponding to the lowest frequency, and it has miniaturization characteristics.

[0017] This invention rationally designs an ultra-wideband feed network, including a multi-section impedance transformer and a microstrip slotted balun structure, enabling it to receive electromagnetic waves with a target bandwidth. This invention also rationally designs a Vivaldi antenna, achieving ultra-wideband, miniaturization, and high radiation gain through edge slotting, resistance loading, and artificial surface plasmons. Simulation results show that the antenna achieves high radiation gain in the frequency range of 0.27 GHz to 18 GHz. 11 |<-10dB, at 0.2GHz|S 11 With a voltage level of -6dB, the antenna exhibits excellent radiation performance in the 0.2GHz to 18GHz frequency band and good directivity throughout its entire operating band. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of the ultra-wideband miniaturized Vivaldi antenna of the present invention.

[0019] Figure 2 This is a schematic diagram of the front structure of the ultra-wideband miniaturized Vivaldi antenna of the present invention.

[0020] Figure 3 This is a schematic diagram of the reverse side structure of the ultra-wideband miniaturized Vivaldi antenna of the present invention.

[0021] Figure 4 The simulation results show the antenna reflection coefficient of the ultra-wideband miniaturized Vivaldi antenna of this invention.

[0022] Figures 5 to 10 The simulation results show the antenna radiation pattern of the ultra-wideband miniaturized Vivaldi antenna of this invention. Wherein: Figure 5 Corresponding to 0.2GHz; Figure 6 Corresponding to 2GHz; Figure 7 Corresponding to 6GHz; Figure 8 Corresponding to 10GHz; Figure 9 Corresponding to 14GHz; Figure 10 Corresponding to 18GHz.

[0023] The labels in the figure are as follows: 1 is the top layer gradient groove metal patch, 2 is the bottom layer impedance transformation microstrip line, 3 is the bottom layer fan-shaped microstrip line, 4 is the bottom layer circular groove, 5 is the rectangular groove, 6 is the exponential gradient groove, 7 is the top layer rectangular metal patch, 8 is the top layer artificial surface plasma, 9-12 are the top layer resistors, 13 is the dielectric substrate, and 14 is the edge-symmetrical rectangular groove. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments: This embodiment is implemented under the premise of the technical solution of the present invention, and provides detailed implementation methods and specific operation processes, but the protection scope of the present invention is not limited to the following embodiments.

[0025] like Figure 1-4 As shown, the novel ultra-wideband miniaturized Vivaldi antenna provided by this invention operates in the frequency band from 0.2 GHz to 18 GHz. It consists of three parts: the antenna, the feed network, and the artificial surface plasma; the antenna dimensions are 308 × 180 × 0.8 mm. 3 (Length × Width × Height). This embodiment includes: an antenna section with a gradient groove metal patch 1 (including a circular groove 4, a rectangular groove 5, an exponential gradient groove 6, and two symmetrical rectangular grooves 14 at the edge), a rectangular metal patch 7, and resistors 9-12; a feed network section with an impedance transformation microstrip line 2 and a fan-shaped microstrip line 3; and finally, an artificial surface plasmon 8 and a dielectric substrate 13.

[0026] like Figure 1-4 As shown, the end opening size of the gradient groove metal patch 1 in this embodiment, 160mm, is determined by the lowest frequency of the operating frequency band, and the rectangular groove width of the gradient groove metal patch 1, 1.4mm, is determined by the highest frequency of the operating frequency band; the curve formula of the exponential gradient groove is described as follows:

[0027] y = C1*e R*x +C2

[0028] Where C1 is 9.81297, C2 is -15.9383, and R is 0.01.

[0029] The symmetrical rectangular groove 14 of the gradient groove metal patch 1 is 10mm wide, which extends the surface current path, lowers the resonant frequency, and achieves the purpose of expanding the low-frequency bandwidth and improving the impedance matching of the low-frequency band; the rectangular metal patch 7 is 28.4mm long and 10mm wide; the added resistors 9-12 have a resistance of 100Ω, which absorbs the end current, thereby reducing the reflection coefficient of the low-frequency band, improving the impedance matching of the entire frequency band, and achieving the purpose of miniaturization.

[0030] In the design of the feed network, a six-section impedance transformer microstrip transmission line 2 is used. The lengths of the first to sixth impedance transformer sections are 50mm, 30mm, 15mm, 10mm, 8.6mm, and 8mm, respectively, and their dimensions are determined by the center frequency wavelength. The widths of the first to sixth impedance transformer sections are 1.5mm, 1.2mm, 0.9mm, 0.7mm, 0.5mm, and 0.35mm, respectively, to achieve impedance transformation from 50Ω to 100Ω, improve antenna impedance matching, and reduce losses. A fan-shaped microstrip line 3 with a radius of 9mm and an angle of 180° is added after the impedance transformer. The rectangular slot 5 has dimensions of 2×1.4mm. 2 (Length × Width), with a circular slot 4 added behind it, with a radius of 20mm, so that the end of the slot line and the microstrip line resonate, realizing the connection of the impedance discontinuity from the microstrip line to the slot line, and achieving wideband within the target bandwidth;

[0031] Artificial surface plasma 8 was added in the middle of the gradient groove of the gradient groove metal patch 1. Its unit is an I-shaped structure, which is composed of periodic extension of I-shaped units. Its dimensions are 2.4 mm long, 5 mm high, 0.5 mm line width, and 23 cycles, which can improve the radiation gain in the high frequency band.

[0032] The FR4 dielectric substrate has a dielectric constant of 4.4, a loss tangent of 0.015, and a thickness of 0.8 mm. The metal layer material is copper, with a thickness of 0.035 mm.

[0033] like Figure 1 As shown, the dimensions of the ultra-wideband miniaturized Vivaldi antenna described in this embodiment are 308×180×0.8mm. 3 (Length × Width × Height), i.e., 0.16λ0 × 0.28λ0 mm 2 λ0 is the free space wavelength corresponding to the lowest frequency, and it has miniaturization characteristics.

[0034] like Figure 4The reflection coefficient of the ultra-wideband miniaturized Vivaldi antenna in this embodiment is shown. The horizontal axis represents the frequency variable in GHz, and the vertical axis represents the reflection coefficient variable in dB. Simulation results show that the ultra-wideband miniaturized Vivaldi antenna of this invention has |S11| < -10 dB in the frequency range of 0.27 GHz to 18 GHz, and |S11| < -10 dB at 0.2 GHz. 11 With a relative impedance bandwidth of 193%, it exhibits ultra-wideband characteristics, with a value of -6dB.

[0035] like Figure 5-10 The diagram shows the radiation characteristics of the ultra-wideband miniaturized Vivaldi antenna of this embodiment. The horizontal axis represents the frequency variable in GHz, and the vertical axis represents the gain in dBi. Simulation results show that the ultra-wideband miniaturized Vivaldi antenna of this invention has a gain of -13.3 dBi at 0.2 GHz; 6.42 dBi at 2 GHz; 10.1 dBi at 6 GHz; 8.68 dBi at 10 GHz; 3.91 dBi at 14 GHz; and 2.5 dBi at 18 GHz.

[0036] The technical solutions of the present invention are not limited to the specific examples mentioned above. For example, the present invention is an ultra-wideband miniaturized Vivaldi antenna that operates in the range of 0.2 GHz to 18 GHz. By changing the size, it can be applied to other bands. All technical modifications made according to the technical solutions of the present invention fall within the protection scope of the present invention.

Claims

1. A miniaturized Vivaldi antenna with ultra-wideband capability, characterized in that, The system includes a dielectric substrate (13), the upper surface of which contains an exponentially tapered slotted main body Vivaldi antenna, namely a tapered slot metal patch (1), four resistors (9-12) and two rectangular metal patches (7), and an artificial surface plasma (8); the tapered slot metal patch (1) includes a rectangular slot (5), an exponentially tapered slot (6) and an edge rectangular slot (14); the lower surface of the substrate is a feed network, which includes six impedance transformation microstrip lines (2), a fan-shaped microstrip line (3) and a circular slot (4); the main body Vivaldi antenna (1) is centered and aligned with the dielectric substrate (13), the four resistors (9-12) are placed at the ends of the main body Vivaldi antenna (1), and the resistors are connected to the two rectangular metal patches (7) behind them; the artificial surface plasma (8) is placed in the middle of the tapered slot of the main body Vivaldi antenna (1) to improve the radiation gain in the high-frequency band; the multi-section impedance transformer and microstrip slotted line structure of the feed network are aligned with the circular slot of the Vivaldi antenna. The antenna, artificial surface plasma (8), and bottom feed network are respectively attached to the upper and lower surfaces of the dielectric substrate (13) without any gaps; The gradient groove metal patch (1) in the upper antenna is aligned with the bottom of the dielectric substrate (13), and the center of the gradient groove metal patch (1) has three grooves: a circular groove (4), a rectangular groove (5) and an exponential gradient groove (6), which are connected from bottom to top; two resistors (11-12) are connected to the rear end of the gradient groove metal patch (1), and two resistors (9-10) are connected to the end; rectangular metal patches (7) are connected to the resistors (9-10); the gradient groove metal patch (1) and the rectangular metal patch (7) are aligned with the left and right sides of the dielectric substrate (13); In the lower-level feed network, the first impedance transformation microstrip line of the six impedance transformation microstrip lines (2) is aligned with the bottom of the dielectric substrate (13), and each impedance transformation microstrip line is connected end to end; the third impedance transformation microstrip line is designed with a right-angle bend; the last impedance transformation microstrip line (2) is connected to the fan-shaped microstrip line (3), and its end is aligned with the edge of the rectangular slot (5); Artificial surface plasma (8) is located at the center of the rear end of the gradient groove; it is composed of I-shaped structures arranged in a periodic extension.

2. The ultra-wideband miniaturized Vivaldi antenna according to claim 1, characterized in that, In the feed network, six impedance transformation microstrip lines (2) are designed to achieve impedance transformation from 50 Ω to 100 Ω, so as to improve the antenna impedance matching and reduce loss. A fan-shaped microstrip line (3) is added after the impedance transformer, and a circular slot (4) is added after the rectangular slot (5) so that the ends of the slot line and the microstrip line resonate, which is used to achieve the connection of the impedance discontinuity from the microstrip line to the slot line, and achieve wideband within the target bandwidth.

3. The ultra-wideband miniaturized Vivaldi antenna according to claim 2, characterized in that, An exponential gradient groove is designed in the gradient groove metal patch (1) for radiation; a rectangular groove (14) is opened at the edge of the gradient groove metal patch (1) to extend the surface current path, reduce the resonant frequency, and achieve the purpose of expanding the low frequency bandwidth and improving the impedance matching of the low frequency band; a dissipation resistor (9-12) is added at the end of the gradient groove metal patch (1) to absorb the end current, which is used to reduce the reflection coefficient of the low frequency band and improve the impedance matching of the entire frequency band.

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