A receiving antenna integrated with a low-impedance terahertz detector

Abstract

The application discloses a receiving antenna integrated with a low-impedance terahertz detector, which comprises a low-impedance terahertz detector located at the center, one crab claw-shaped metal sheet on each side, crab claw connecting arm metal sheets located between the terahertz detector and the two crab claw-shaped metal sheets and serving as connecting arms, and the overall structure is symmetric about the center. The application realizes effective integration of the on-chip low-impedance antenna and the low-impedance terahertz detector, realizes different working modes in different frequency bands, works in a resonant mode in a low frequency band and works in a traveling wave mode in a high frequency band, and realizes different working bandwidths in different frequency bands, that is, narrowband in the low frequency band and wideband in the high frequency band.

Description

Technical Field

[0001] This invention relates to a terahertz communication device, and more particularly to a terahertz multifunctional antenna. Background Technology

[0002] 6G mobile communication largely focuses on antenna design and device integration in the terahertz band. However, terahertz signals face severe atmospheric attenuation during transmission through the atmosphere, necessitating the development of ultra-sensitive terahertz detectors to address this issue. High-temperature superconducting terahertz detectors operate in the liquid nitrogen temperature range and offer advantages over semiconductor terahertz detectors, including wider detection bandwidth and higher sensitivity. High-temperature superconducting yttrium barium copper oxide (YBa₂Cu₃O₃) detectors are particularly effective in this field. 7-δ High-bandgap devices, represented by the YBCO Josephson junction detector, have shown great potential for high cutoff frequency and wide bandwidth detection in many applications such as terahertz signal generation, detection and mixing, becoming a highly competitive core functional unit in the terahertz field.

[0003] However, the normal-state resistance of high-temperature superconducting Josephson junction detectors is relatively low, typically only 1Ω to 40Ω, resulting in low coupling efficiency between them and the receiving antenna used to receive terahertz signals. Therefore, improving the coupling efficiency between terahertz signals and detectors has become a research hotspot and a key breakthrough direction in this field. Developing novel terahertz antennas suitable for low-impedance devices is the primary solution to improve coupling efficiency.

[0004] In existing technologies, receiving antennas based on superconducting terahertz detection technology include two types: a ring slot antenna fed by a coplanar waveguide with an input impedance of approximately 30Ω, and a butterfly-loaded meandering wire antenna fed by a coplanar stripline with an input impedance of approximately 20Ω. Both antennas are resonant antennas, which have narrow bandwidths and are generally selected for specific frequency applications. However, 6G mobile communication requires multi-scenario applications, and antennas need to be able to adapt to different operating modes to achieve free switching between narrowband and broadband. Therefore, multifunctional terahertz antennas for low-impedance terahertz detectors urgently need to be developed. Summary of the Invention

[0005] Purpose of the invention: In view of the above-mentioned prior art, a receiving antenna integrating a low-impedance terahertz detector is proposed to solve the problems of impedance mismatch and low coupling efficiency between existing antennas and low-impedance terahertz detectors. At the same time, the antenna can be adapted to the target terahertz frequency band.

[0006] Technical solution: A receiving antenna integrating a low-impedance terahertz detector, including a low-impedance terahertz detector located at the center, a crab claw-shaped metal plate on each side of the low-impedance terahertz detector, and a crab claw connecting arm metal plate between the terahertz detector and the crab claw-shaped metal plates on both sides, the crab claw connecting arm metal plate correspondingly connecting the low-impedance terahertz detector and the crab claw-shaped metal plates on both sides.

[0007] Furthermore, the crab claw-shaped metal sheet, the crab claw connecting arm metal sheet, and the low-impedance terahertz detector are distributed in the same horizontal direction; the two crab claw-shaped metal sheets and the two crab claw connecting arm metal sheets are symmetrically distributed about the center.

[0008] Furthermore, the overall shape of the crab claw-shaped metal piece is an open shape resembling a crab claw, formed by two hyperbolic curves, and divided into two parts by the horizontal line: a large claw arm on one side and a small claw arm on the other side.

[0009] Furthermore, the distal ends of the large and small pincer arms are pointed, and the obtuse angle formed by the line connecting the distal ends of the large and small pincer arms to the apex of the hyperbola at the opening of the crab pincers and the horizontal line is respectively... θ 1. θ 2; The maximum width of the small clamp arm is b The lateral distance between the maximum width and the vertex of the outer hyperbola is a The maximum width of the large clamp arm is d The lateral distance between the maximum width and the vertex of the outer hyperbola is c The maximum width is located in the middle area of ​​the clamp arm in the horizontal direction.

[0010] Furthermore, the overall shape of the crab claw connecting arm metal plate is an elliptical structure symmetrical about the horizontal line, with an arc-shaped notch at one end; the arc-shaped notch is adapted to the shape of the apex of the hyperbola on the outer side of the crab claw-shaped metal plate, and the two are seamlessly connected to form a continuous metal conductive path.

[0011] Furthermore, the length of the metal plate connecting the crab claw arm is... l The widest dimension is 2 m The width gradually changes from the end connected to the low-impedance terahertz detector to the end connected to the crab claw-shaped metal plate, specifically by first gradually widening and then gradually narrowing, with the maximum width appearing in the middle region of the connecting arm.

[0012] Furthermore, the receiving antenna operates in resonant mode in the low-frequency band and in traveling wave mode in the high-frequency band.

[0013] Furthermore, the receiving antenna has different operating bandwidths for different frequency bands, achieving narrowband in the low-frequency band and broadband in the high-frequency band.

[0014] Beneficial effects: This invention achieves effective integration of an on-chip low-impedance antenna and a low-impedance terahertz detector; it realizes different operating modes for different frequency bands, with the low-frequency band operating in resonant mode and the high-frequency band operating in traveling wave mode; it realizes different operating bandwidths for different frequency bands, with the low-frequency band achieving narrowband and the high-frequency band achieving broadband. Attached Figure Description

[0015] Figure 1 A schematic diagram of the receiving antenna structure for an integrated low-impedance terahertz detector; Figure 2 A schematic diagram of the receiving antenna parameters for an integrated low-impedance terahertz detector; Figure 3 Simulation diagram of the reflection coefficient at the low-impedance terahertz detector in the receiving antenna; Figure 4 Simulation diagram of the far-field radiation direction of the receiving antenna for an integrated low-impedance terahertz detector at different resonant frequencies. Detailed Implementation

[0016] The invention will now be further explained with reference to the accompanying drawings.

[0017] like Figure 1 As shown, a receiving antenna for an integrated low-impedance terahertz detector has a crab claw-shaped metal plate 1 on each side of the low-impedance terahertz detector 3 located at the center. A crab claw connecting arm metal plate 2 is provided between the terahertz detector 3 and the crab claw-shaped metal plates 1 on both sides. The crab claw connecting arm metal plate 2 connects the low-impedance terahertz detector 3 to the crab claw-shaped metal plates 1 on both sides.

[0018] Crab claw-shaped metal plate 1, crab claw connecting arm metal plate 2, and low-impedance terahertz detector 3 are distributed along the same horizontal line. Both the pair of crab claw-shaped metal plates 1 and the pair of crab claw connecting arm metal plates 2 are symmetrically distributed about the center.

[0019] The crab claw-shaped metal piece 1 has an overall shape resembling the open form of a crab claw, formed by two hyperbolas. It is divided into two parts by a horizontal line: a large claw arm on one side and a small claw arm on the other. The distal ends of both the large and small claw arms are pointed. The obtuse angle formed by the line connecting the distal ends of the large and small claw arms to the apex of the hyperbola at the opening of the crab claw (the intersection of the hyperbola and the horizontal line) and the horizontal line is as follows: θ 1. θ 2. The maximum width of the small clamp arm is b The lateral distance between the maximum width and the root (the vertex of the outer hyperbola) is a The maximum width of the large clamp arm is d The lateral distance between the maximum width and the root is cThe maximum width is located in the middle area of ​​the clamp arm in the horizontal direction.

[0020] The overall shape of the crab claw connecting arm metal plate 2 is an elliptical structure symmetrical about the horizontal line, with an arc-shaped notch at one end. The length of the crab claw connecting arm metal plate 2 is... l The widest dimension is 2 m The width of the connecting arm gradually changes from the end connected to the low-impedance terahertz detector 3 to the end connected to the crab claw-shaped metal plate 1. Specifically, it gradually widens first and then gradually narrows, with the maximum width appearing in the middle region of the connecting arm. The shape of one end of the arc-shaped notch matches the apex of the hyperbola on the outer side of the crab claw-shaped metal plate 1, and the two are seamlessly connected to form a continuous metal conductive path for electrically connecting the crab claw-shaped metal plate 1 to the low-impedance terahertz detector 3.

[0021] In this embodiment, the low-impedance terahertz detector is a high-temperature superconducting Josephson junction detector with an impedance of approximately 20Ω.

[0022] The size of the receiving antenna is related to its resonant frequency, so the structural parameters of the receiving antenna are adjusted according to the bandwidth requirements.

[0023] The total length of the receiving antenna is related to its resonant frequency. The receiving antenna has different operating modes for different frequency bands: the physical size of the low-frequency receiving antenna is about half the wavelength of the waveguide, and the current distribution exhibits a resonant mode. The energy is mainly concentrated at the edge of the hyperbola on the outside of the connecting arm and the crab claw. The smaller the length and the larger the width of the connecting arm, the better it can be adapted to low-impedance terahertz detectors. The physical size of the high-frequency receiving antenna is about equal to or greater than one waveguide wavelength, and the current distribution exhibits a traveling wave mode. The opening of the crab claw provides multiple paths for the current distribution, and there are multiple traveling wave modes with different current distributions for different operating wavelengths.

[0024] In addition, the receiving antenna has different operating bandwidths for different frequency bands. The low-frequency band has a narrow operating bandwidth due to the single current resonant mode, while the high-frequency band has a wide operating bandwidth due to the multi-path current traveling wave mode. In other words, the receiving antenna has both narrowband resonant mode and wideband traveling wave mode.

[0025] In practical applications, the receiving antenna of the integrated low-impedance terahertz detector is set on a silicon hemispherical lens to mimic a semi-infinite space, or on an electromagnetic bandgap structure to eliminate the surface wave effect caused by a thick dielectric substrate.

[0026] like Figure 1 and 2 As shown, in this embodiment, the antenna material is set as an ideal conductor in the CST simulation software, placed on a magnesium oxide (relative permittivity of 9.6) substrate, and the low-impedance terahertz detector is characterized using a 20Ω discrete port equivalent. The antenna parameters are as follows:l =55 μm, m =40 μm, a =70 μm, b =20 μm, c =80 μm, d =80 μm, θ 1 = 150° θ 2 = 130°, the reflection coefficient at the detector is as follows Figure 3 As shown, the antenna operates in resonant mode in the low-frequency band centered at 152 GHz, and in traveling-wave mode from 446 GHz to 713 GHz, with a bandwidth of up to 267 GHz in traveling-wave mode. The far-field radiation patterns under different operating modes are shown in the figure. Figure 4 As shown, the directivity coefficients at 151 GHz and 478 GHz are 8.3 dBi and 8.5 dBi, respectively.

[0027] It should be noted that the high-temperature superconducting Josephson junction detector in this embodiment can be replaced with any other low-impedance terahertz device.

[0028] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A receiving antenna integrating a low-impedance terahertz detector, characterized in that, It includes a low-impedance terahertz detector (3) located at the center, a crab claw-shaped metal plate (1) on each side of the low-impedance terahertz detector (3), and a crab claw connecting arm metal plate (2) between the terahertz detector (3) and the crab claw-shaped metal plates (1) on both sides. The crab claw connecting arm metal plate (2) connects the low-impedance terahertz detector (3) to the crab claw-shaped metal plates (1) on both sides.

2. The receiving antenna of the integrated low-impedance terahertz detector according to claim 1, characterized in that, The crab claw-shaped metal sheet (1), the crab claw connecting arm metal sheet (2), and the low-impedance terahertz detector (3) are distributed in the same horizontal direction; the two crab claw-shaped metal sheets (1) and the two crab claw connecting arm metal sheets (2) are symmetrically distributed about the center.

3. The receiving antenna of the integrated low-impedance terahertz detector according to claim 1, characterized in that, The crab claw-shaped metal piece (1) has an overall shape resembling the opening of a crab claw, formed by two hyperbolic curves, and divided into two parts by the horizontal line: a large claw arm on one side and a small claw arm on the other side.

4. The receiving antenna of the integrated low-impedance terahertz detector according to claim 3, characterized in that, The distal ends of the large and small pincers are pointed. The obtuse angle formed by the lines connecting the distal ends of the large and small pincers to the apex of the hyperbola at the opening of the crab pincers and the horizontal line is respectively... θ 1. θ 2; The maximum width of the small clamp arm is b The lateral distance between the maximum width and the vertex of the outer hyperbola is a The maximum width of the large clamp arm is d The lateral distance between the maximum width and the vertex of the outer hyperbola is c The maximum width is located in the middle area of ​​the clamp arm in the horizontal direction.

5. The receiving antenna of the integrated low-impedance terahertz detector according to claim 3, characterized in that, The overall shape of the crab claw connecting arm metal plate (2) is an elliptical structure symmetrical about the horizontal line and with an arc-shaped notch at one end; the arc-shaped notch is adapted to the shape of the apex of the hyperbola on the outer side of the crab claw shaped metal plate (1), and the two are seamlessly connected to form a continuous metal conductive path.

6. The receiving antenna of the integrated low-impedance terahertz detector according to claim 5, characterized in that, The length of the metal plate (2) connecting the crab claw is l The widest dimension is 2 m The width gradually changes from the end connected to the low-impedance terahertz detector (3) to the end connected to the crab claw-shaped metal plate (1), specifically, it gradually widens first and then gradually narrows, with the maximum width appearing in the middle region of the connecting arm.

7. The receiving antenna of the integrated low-impedance terahertz detector according to any one of claims 1-6, characterized in that, The receiving antenna operates in resonant mode in the low-frequency band and in traveling wave mode in the high-frequency band.

8. The receiving antenna of the integrated low-impedance terahertz detector according to claim 7, characterized in that, The receiving antenna has different operating bandwidths for different frequency bands; it achieves narrowband in low-frequency bands and broadband in high-frequency bands.

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