A terahertz antenna integrating high-temperature superconducting high-order in-phase series mixer

Abstract

The present invention discloses a terahertz antenna integrated with a high-temperature superconducting high-order in-phase series mixer, comprising a terahertz antenna; the terahertz antenna comprises a butterfly metal layer at both ends; a plurality of low-impedance mixers are embedded between the butterfly metal layers at both ends; and the plurality of low-impedance mixers are connected by a meandering metal layer. The present invention is to design a terahertz antenna with low input impedance with multi-source excitation, and embed a high-order in-phase series low-impedance mixer in the terahertz antenna to complete impedance matching without affecting antenna performance; the butterfly-loaded meandering antenna can embed a plurality of low-impedance mixers in the meandering line to complete impedance matching without affecting antenna performance; the length of the meandering line between the mixers can be arbitrarily adjusted to adjust the active impedance and complete the matching with the mixer impedance; the embedded low-impedance mixer can be increased or decreased according to the needs of actual applications, and the impedance matching between the antenna and the mixer is improved, thereby increasing the harmonic order and reducing the impedance mismatch.

Description

Technical Field

[0001] The invention relates to a terahertz antenna integrating a high-temperature superconducting high-order in-phase series mixer, and belongs to the field of terahertz communication and superconductivity. Background Art

[0002] Terahertz (THz) waves are electromagnetic waves of 0.1-10 THz. With its considerable absolute bandwidth, THz communication has the advantages of high transmission rate, large capacity, strong directivity, high security and good penetration. However, due to the severe atmospheric attenuation in the THz band, higher requirements are placed on the effective detection of ultra-sensitive THz receivers. Semiconductor-based heterodyne receivers have been developed using Schottky barrier diodes, high electron mobility transistors, complementary metal oxide semiconductors, etc. They can operate at room temperature but require relatively high local oscillator (LO) power, which poses challenges as the operating frequency increases. Low-temperature superconducting (LTS) hot electron bolometers (HEBs) and superconductor-insulator-superconductor (SIS) mixers can operate at lower LO powers and are the most sensitive frequency downconverters to date. However, LTS devices need to be cooled to liquid helium temperature (4.2 K) or below, which requires expensive liquid helium and cryogenic equipment. High temperature superconducting (HTS) mixers can operate at liquid nitrogen temperature (77K). High temperature superconducting mixers have the advantages of low cryogenic cost, wide bandwidth, high sensitivity, low local oscillator power requirement, and high harmonics, making them an ideal choice for terahertz heterodyne receivers.

[0003] Due to the low power consumption and high cost of THz sources, high-order harmonic mixers are particularly important in THz communications in terms of reducing local oscillator costs and improving mixing performance. The higher the number of harmonics, the lower the LO frequency and the lower the cost. Wang Huabing et al. reported Bi2Sr2CaCu2O 8+x (BSCCO) intrinsic mixer achieved 98th harmonic mixing in 100 GHz detection. Considering impedance matching, Du Jia, Gao Xiang and others integrated and studied YBa2Cu3O 7-δ(YBCO) step edge mixer slot antenna, using coplanar waveguide feeding. So far, the maximum harmonic order they measured is 31, which is used for 600 GHz detection. For the 210 GHz atmospheric window, a new terahertz antenna is introduced to improve the coupling efficiency between the mixer and the antenna, and up to 146 harmonic mixing in the YBCO dual crystal mixer is achieved. Subsequently, a mixer s mixer with a series structure was proposed. Thanks to the synchronous operation of three series-connected mixers, 154 harmonic mixing was achieved. Although the three series-connected YBCO dual crystal mixers work synchronously, there is an impedance mismatch problem between the antenna and each mixer, which has not yet been solved. Therefore, if the impedance matching between the antenna and each mixer can be improved, the harmonic order is expected to be further improved. Therefore, a suitable antenna is required to match the impedance of each YBCO dual crystal mixer in series. Summary of the invention

[0004] In view of the problems existing in the above-mentioned prior art, the present invention provides a terahertz antenna integrating a high-temperature superconducting high-order in-phase series mixer, thereby solving the above-mentioned technical problems.

[0005] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a terahertz antenna integrating a high-temperature superconducting high-order in-phase series mixer, comprising a terahertz antenna; the terahertz antenna comprises a butterfly-shaped metal layer at both ends; a plurality of low-impedance mixers are embedded between the butterfly-shaped metal layers at both ends; the plurality of low-impedance mixers are connected by a meandering line metal layer.

[0006] By adopting the above technical solution, the butterfly-loaded meandering line antenna can embed multiple low-impedance mixers in the meandering line, thereby achieving impedance matching without affecting the antenna performance.

[0007] Furthermore, the low impedance mixers are arranged in even number, and the series-connected mixers are placed at the intersection of the meandering metal layer and the center line of the butterfly metal layer, and are symmetrically placed about the central symmetric point of the terahertz antenna.

[0008] By adopting the above technical solution and arranging the central symmetrical points, a symmetrical radiation pattern and a consistent resonant frequency can be ensured.

[0009] Furthermore, the meandering line metal layer is provided with a plurality of meandering lines connected to the low impedance mixer, and the meandering lines have different lengths.

[0010] By adopting the above technical solution, the length of the meandering line between the mixers can be adjusted arbitrarily to adjust the active impedance, thereby achieving impedance matching with the mixers;

[0011] Furthermore, no mixer is placed at the central symmetrical point of the meandering metal layer, and four low-impedance mixers or two low-impedance mixers may be placed at other positions of the central line of the meandering metal layer.

[0012] Furthermore, the impedance of the low-impedance mixer is 0-20 ohms.

[0013] Furthermore, the electromagnetic wave on the meander line metal layer is transmitted to the butterfly-shaped metal layers loaded at both ends in the form of traveling waves, or forms standing waves together with the loaded butterfly-shaped metal layers to work.

[0014] Furthermore, a silicon super hemisphere lens is placed on the back side of the substrate where the terahertz antenna is located.

[0015] By adopting the above technical solution, a silicon super hemisphere lens is placed on the back of the substrate, thereby eliminating the substrate surface wave effect of the terahertz antenna.

[0016] The beneficial effects of the present invention are as follows: the present invention designs a terahertz antenna with low input impedance for multi-source excitation, and embeds a high-order in-phase series low-impedance mixer in the terahertz antenna to achieve impedance matching without affecting the antenna performance; the butterfly-loaded meandering line antenna can embed multiple low-impedance mixers in the meandering line to achieve impedance matching without affecting the antenna performance; the length of the meandering line between the mixers can be adjusted arbitrarily to adjust the active impedance to achieve impedance matching with the mixer; the embedded low-impedance mixer can be increased or decreased according to the needs of actual applications, and by improving the impedance matching between the antenna and the mixer, the harmonic order can be further increased and the impedance mismatch can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A schematic diagram of the structure of a butterfly-loaded meander line antenna embedded with four low-impedance mixers according to an embodiment of the present invention;

[0018] Figure 2 It is a schematic diagram of an active reflection coefficient simulation diagram in which four low-impedance mixers are embedded at positions A, B, C and D according to the first embodiment of the present invention;

[0019] Figure 3 This is a schematic diagram of an active reflection coefficient simulation diagram of a second embodiment of the present invention in which two low impedance mixers are embedded at positions A and D;

[0020] Figure 4 This is a schematic diagram of an active reflection coefficient simulation diagram of two low impedance mixers embedded at positions B and C in Example 3 of the present invention;

[0021] Figure 5 This is a simulation diagram of the far-field radiation direction of four low-impedance mixers embedded at positions A, B, C and D according to the first embodiment of the present invention;

[0022] Figure 6 This is a simulation diagram of the far-field radiation direction of the second embodiment of the present invention in which two low-impedance mixers are embedded at positions A and D;

[0023] Figure 7 This is a simulation diagram of the far-field radiation direction of two low-impedance mixers embedded at positions B and C of the third embodiment of the present invention;

[0024] Figure 8 FIG. 1 is a schematic diagram with relevant parameters according to Embodiment 1 of the present invention.

[0025] In the figure: 1. Butterfly metal layer, 2. Meandering line metal layer, 3. Low impedance mixer. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the present invention more clear, the present invention is further described in detail below through the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the scope of the present invention.

[0027] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by technicians in the technical field to which the present invention belongs. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0028] like Figure 1 and Figure 8 As shown, it is a terahertz antenna integrating a high-temperature superconducting high-order in-phase series mixer, comprising a terahertz antenna; the terahertz antenna comprises a butterfly metal layer 1 at both ends; a plurality of low-impedance mixers 3 are embedded between the butterfly metal layers 1 at both ends; the plurality of low-impedance mixers 3 are connected by a meandering metal layer 2; the series mixers are placed at the intersection of the meandering metal layer 2 and the center line of the butterfly metal layer 1, and are symmetrically placed about the central symmetric point of the terahertz antenna; the meandering metal layer 2 is provided with a plurality of meandering lines connecting the low-impedance mixers 3, and the lengths of the meandering lines are different. The impedance of the low-impedance mixer 3 is 0-20 ohms. The electromagnetic wave on the meandering metal layer 2 is transmitted to the butterfly metal layer 1 loaded at both ends in the form of a traveling wave, or forms a standing wave with the loaded butterfly metal layer 1 to work. A silicon super hemispherical lens is placed on the back of the substrate where the terahertz antenna is located.

[0029] Embodiment 1:

[0030] Reference Figure 2 and Figure 5, which is provided with four symmetrically distributed low-impedance mixers 3, which are respectively set at positions A, B, C and D. In the CST simulation software, the antenna material is set as an ideal conductor and placed on a magnesium oxide (relative dielectric constant of 9.6) substrate. The detectors are represented by 20 ohm discrete ports, and multi-port active simulation is performed. The active reflection coefficient and far-field radiation pattern are shown as follows: Figure 2 and Figure 5 As shown; when the antenna parameters =183 μm, =752 μm, =56 μm, =8 μm, =11 μm, =22 μm, =16 μm, =15 μm, = = =75 μm, the active reflection coefficients of the four symmetrically distributed low impedance mixers (3) on A, B, C and D are -19.5 dB, -24.4 dB, -24.8 dB and -19.5 dB respectively at 218 GHz, and the directivity coefficient reaches 9.06 dBi;

[0031] Embodiment 2:

[0032] Reference Figure 2 and Figure 6 , which is provided with two symmetrically distributed low impedance mixers 3, respectively arranged at Figure 1 The antenna material is set to be an ideal conductor and placed on a magnesium oxide (relative dielectric constant of 9.6) substrate in the CST simulation software. The detectors are represented by discrete ports of 20 ohms. Multi-port active simulation is performed. The active reflection coefficient and far-field radiation pattern are shown in the figure. Figure 2 and Figure 5 As shown; when the antenna parameters =183 μm, =752 μm, =56 μm, =8 μm, =11 μm, =22 μm, =16 μm, =15 μm, = = =75 μm, the two symmetrically distributed low impedance mixers (3) on A and D have an active reflection coefficient of -11.8 dB and a directivity of 9.4 dBi at 218 GHz.

[0033] Embodiment three:

[0034] Reference Figure 3 and Figure 7 , which is provided with two symmetrically distributed low impedance mixers 3, respectively arranged at Figure 1 In the CST simulation software, the antenna material is set to be an ideal conductor and placed on a magnesium oxide (relative dielectric constant of 9.6) substrate. The detectors are represented by 20 ohm discrete ports, and multi-port active simulation is performed. The active reflection coefficient and far-field radiation pattern are shown in Figure 2. Figure 2 and Figure 5 As shown; when the antenna parameters =183 μm, =752 μm, =56 μm, =8 μm, =11 μm, =22 μm, =16 μm, =15 μm, = = =75 μm, the B and C2 ports are excited, and the impedance matching at 218 GHz is good, but the best is at 219 GHz, with a reflection coefficient of -11.2 dB and a directivity of 8.81 dBi.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modification, equivalent substitution or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A terahertz antenna integrating a high-temperature superconducting high-order in-phase series mixer, characterized in that: The invention comprises a terahertz antenna; the terahertz antenna comprises butterfly-shaped metal layers (1) at two ends; a plurality of low-impedance mixers (3) are embedded between the butterfly-shaped metal layers (1) at two ends; the plurality of low-impedance mixers (3) are connected via a meandering metal layer (2); the series-connected mixers are placed at the intersection of the meandering metal layer (2) and the center line of the butterfly-shaped metal layer (1), and are symmetrically placed about the central symmetric point of the terahertz antenna; the meandering metal layer (2) is provided with a plurality of sections connecting the low-impedance mixers (3) The invention relates to a meandering line having multiple sections of unequal lengths; no mixer is placed at the central symmetric point of the meandering line metal layer (2), and two or four low-impedance mixers (3) are placed; the impedance of the low-impedance mixer (3) is 0-20 ohms; the electromagnetic wave on the meandering line metal layer (2) is transmitted in the form of a traveling wave to the butterfly-shaped metal layer (1) loaded at both ends, or forms a standing wave with the loaded butterfly-shaped metal layer (1) to work; and a silicon super hemispherical lens is placed on the back of the substrate where the terahertz antenna is located.

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