阅读说明：本技术 一种用于高温等离子体诊断技术的耐高温聚焦透镜天线 (High-temperature-resistant focusing lens antenna for high-temperature plasma diagnosis technology ) 是由 李小平 赵成伟 张珈珲 刘彦明 孙超 刘东林 于 2019-07-22 设计创作，主要内容包括：本发明属于等离子体参数诊断及测量技术领域,公开了一种用于高温等离子体诊断技术的耐高温聚焦透镜天线,耐高温聚焦透镜,用于对电磁波的折射及聚焦；喇叭馈源,用于发射或接收电磁波信号；天线支架,用于耐高温聚焦透镜及喇叭馈源的支撑及固定；配重块,用于平衡耐高温透镜和喇叭馈源的重量。本发明提供了适用于高温等离子体透射诊断、点聚焦透镜天线,解决了传统喇叭天线不能聚焦、无法耐受高温的缺点。聚焦透镜天线的口径为200mm,聚焦位置位于透镜前方350mm。实测聚焦焦斑＜22mm,极大的减小了电磁波对等离子体绕射的影响。透镜采用耐高温石英材料,在温度低于1100℃下长期稳定工作。(The invention belongs to the technical field of plasma parameter diagnosis and measurement, and discloses a high-temperature-resistant focusing lens antenna for a high-temperature plasma diagnosis technology, wherein the high-temperature-resistant focusing lens is used for refracting and focusing electromagnetic waves; the horn feed source is used for transmitting or receiving electromagnetic wave signals; the antenna bracket is used for supporting and fixing the high-temperature-resistant focusing lens and the horn feed source; and the balancing weight is used for balancing the weight of the high-temperature-resistant lens and the horn feed source. The invention provides a point focusing lens antenna suitable for high-temperature plasma transmission diagnosis, and solves the defects that the traditional horn antenna cannot focus and cannot bear high temperature. The aperture of the focusing lens antenna is 200mm, and the focusing position is 350mm in front of the lens. The actually measured focused focal spot is less than 22mm, and the influence of electromagnetic waves on plasma diffraction is greatly reduced. The lens is made of high-temperature-resistant quartz material and can stably work for a long time at the temperature of less than 1100 ℃.)

1. a high temperature resistant focus lens antenna for high temperature plasma diagnostic techniques, the high temperature resistant focus lens antenna comprising:

The high-temperature resistant focusing lens is used for refracting and focusing electromagnetic waves;

The horn feed source is used for irradiating and feeding the lens antenna by electromagnetic waves;

The antenna bracket is used for supporting and fixing the high-temperature-resistant focusing lens and the horn feed source;

And the balancing weight is used for balancing the weight of the high-temperature-resistant focusing lens and the horn feed source.

2. the refractory focusing lens antenna as defined in claim 1, wherein the refractory focusing lens is fabricated from quartz material.

3. The refractory focusing lens antenna of claim 1, wherein the refractory focusing lens is comprised of a first lens and a second lens;

the first lens converts spherical waves emitted by the horn feed source into plane waves; and the second lens converts the plane wave into a spherical wave again and focuses the spherical wave on a required focal point.

4. The refractory focusing lens antenna of claim 3, wherein the curves of the first lens and the second lens are both hyperbolic, wherein the curve of the first lens is:

Wherein n is the refractive index of the lens, and the value range of x1 is (0, 22.58 mm);

Wherein the curve of the second lens is:

Wherein n is the refractive index of the lens, and the value range of x2 is (0, 14.2 mm).

5. The high temperature resistant focusing lens antenna of claim 1, wherein the horn feed is comprised of a horn section and a waveguide coaxial transition; the material is copper material.

6. The high temperature resistant focusing lens antenna of claim 1, wherein the antenna support is composed of a lens support and a feed support, and the material is high temperature resistant stainless steel.

7. The high temperature resistant focusing lens antenna of claim 1, wherein the weight is made of high temperature resistant stainless steel material.

8. The high temperature resistant focusing lens antenna of claim 1, wherein the high temperature resistant focusing lens antenna for high temperature plasma diagnostic technique operates at a frequency of 26.5-40GHz, the effective aperture of the focusing lens is 200mm, and the antenna is focused at 350mm in front; the geometric dimension parameters of the structure are as follows: f1 was 200mm, F2 was 350mm, H1 was 22.58mm, H2 was 14.2mm, D was θ 1 was 24.2 °, and θ 2 was 15.3 °.

9. A plasma microwave transmission diagnosis and measurement system applying the high-temperature-resistant focusing lens antenna as claimed in any one of claims 1 to 8.

Technical Field

the invention belongs to the technical field of plasma parameter diagnosis or measurement, and particularly relates to parameter diagnosis and measurement of high-temperature plasma.

background

At present, the diagnosis and measurement of plasma parameters are a research hotspot, and the latest diagnosis and measurement technologies are as follows: electrostatic probe methods, spectroscopy, microwave diagnostics, and the like.

the electrostatic probe method, also called Langmuir probe method, proposed by Irving Langmuir in 1924, was the earliest method for plasma characteristic diagnosis and has been used so far. The method utilizes a conductive needle point to measure a volt-ampere characteristic curve of the plasma, and then related parameters of the plasma are calculated. The probe tip is in direct contact with the plasma, so that the measured plasma is inevitably disturbed, and meanwhile, the material of the probe tip often causes certain pollution to the plasma environment, so that the defects exist. Spectroscopic measurement is a measurement method having no influence on plasma, and is also an important means for studying ion transport behavior and measuring plasma parameters by analyzing emission spectra of ions or neutral particles in plasma. The microwave diagnosis method is a non-contact plasma density diagnosis method developed from the sixth and seventies of the 20 th century. The plasma is regarded as a dielectric medium with dispersion characteristics, when microwave penetrates different plasmas, different attenuations and propagation delays can be generated, and key parameters such as electron density can be indirectly deduced according to an electromagnetic wave theory by measuring different attenuations and phase differences of a transmission signal (when the plasmas exist) and a reference signal (when the plasmas do not exist).

in the above research methods for plasma diagnosis, the electrostatic probe needs to be deep inside the plasma, which may cause interference and pollution to the plasma environment, and the spectroscopic measurement, although not deep inside the plasma, has higher equipment and measurement costs, so the microwave transmission diagnosis is the most effective and simple method.

The microwave transmission diagnosis is that a pair of transmitting and receiving antennas are erected at two sides of a plasma region, and the antennas are generally focusing lens antennas. The reason is that the focusing antenna is placed at the central part of the plasma area, so as to minimize the diffraction phenomenon that the microwave signal bypasses the plasma propagation, and therefore, the focusing lens antenna is an essential component for plasma diagnosis. However, the conventional focusing lens antenna uses teflon as a lens, and the melting point of teflon is only 327 ℃. The temperature of the lens is about 1000 ℃ by combining thermodynamic simulation software, so that if the polytetrafluoroethylene material is used for the lens, the polytetrafluoroethylene material is instantly gasified at 1000 ℃, and thus the polytetrafluoroethylene material cannot be used.

In summary, the problems of the prior art are as follows:

(1) the existing electrostatic probe is deep into the plasma, which can cause interference and pollution to the plasma environment, and the spectroscopic measurement is high in equipment and measurement cost although the existing electrostatic probe is not required to be deep into the plasma.

(2) The existing microwave transmission diagnosis is that a pair of transmitting and receiving antennas are erected at two sides of a plasma region, polytetrafluoroethylene is used as a lens, the melting point of the polytetrafluoroethylene is 327 ℃, and the polytetrafluoroethylene is certainly gasified instantly when the temperature is higher than 1000 ℃, so that the existing microwave transmission diagnosis cannot be used.

The difficulty of solving the technical problems is as follows: 1) the diagnosis of the plasma needs to adopt microwave transmission diagnosis, while the microwave antenna needs to have a focusing function, and the smaller the focal spot size is, the better the focal spot size is; 2) the focusing lens needs to withstand high temperatures, which must be > 1000 ℃.

The significance of solving the technical problems is as follows: 1) the high-temperature plasma can be diagnosed more accurately; 2) deepening the understanding of the interaction of the plasma with the electromagnetic field; 3) the selection of the high-temperature resistant material of the focusing lens antenna is expanded more widely.

Disclosure of Invention

Aiming at the problems in the prior art, the invention provides a high-temperature-resistant focusing lens antenna for a high-temperature plasma diagnosis technology.

The invention is realized in such a way that a high temperature resistant focusing lens antenna for high temperature plasma diagnostic technology comprises:

The high-temperature resistant focusing lens is used for refracting and focusing electromagnetic waves;

the horn feed source is used for irradiating and feeding the lens antenna by electromagnetic waves;

the antenna bracket is used for supporting and fixing the high-temperature-resistant focusing lens and the horn feed source;

And the balancing weight is used for balancing the weight of the high-temperature-resistant focusing lens and the horn feed source.

further, the high-temperature-resistant focusing lens is made of quartz materials.

Further, the high-temperature resistant focusing lens consists of a first lens and a second lens;

The first lens converts spherical waves emitted by the horn feed source into plane waves; and the second lens converts the plane wave into a spherical wave again and focuses the spherical wave on a required focal point.

Further, the curves of the first lens and the second lens are both hyperbolic curves, wherein the curve of the first lens is as follows:

Wherein n is the refractive index of the lens, and the value range of x1 is (0, 22.58 mm);

Wherein the curve of the second lens is:

Wherein n is the refractive index of the lens, and the value range of x2 is (0, 14.2 mm).

Further, the horn feed source is formed by coaxially converting a horn part and a waveguide; the material is copper material.

furthermore, the antenna support comprises a lens support and a feed source support, and is made of high-temperature-resistant stainless steel.

Further, the balancing weight is made of high-temperature-resistant stainless steel materials.

Furthermore, the high-temperature plasma diagnosis technology and the high-temperature resistant focusing lens antenna work at the frequency of 26.5-40GHz, the effective caliber of the focusing lens is 200mm, and the antenna is focused at the position 350mm in front.

Another object of the present invention is to provide a plasma microwave transmission diagnosis measurement system of a high temperature resistant focusing lens antenna for high temperature plasma diagnosis technology.

in summary, the advantages and positive effects of the invention are: the invention provides a high-temperature-resistant focusing lens antenna for a high-temperature plasma diagnosis technology, which solves the defects that the traditional horn antenna cannot focus and cannot resist high temperature. The aperture of the point focusing lens antenna is 200mm, the focusing position is 350mm in front of the lens, and the actually measured focusing focal spot is less than 22mm, so that the influence of electromagnetic waves on plasma diffraction is greatly reduced. The lens is made of high-temperature-resistant quartz material and can stably work for a long time at the temperature lower than 1100 ℃. Meanwhile, the dielectric constant epsilon r of the quartz material is 3.8, and if the traditional Teflon material (epsilon r is 2.1) is adopted, the thickness is only 50.5 percent of that of the Teflon material and the weight is 51.5 percent of that of the Teflon material under the same caliber of 200mm, so the invention has important significance in high-temperature plasma transmission diagnosis.

The invention provides a focusing lens antenna capable of resisting high temperature, and provides a method for accurately diagnosing high-temperature plasma. The interaction between the plasma and the electromagnetic wave can be deeply researched through transmission diagnosis of the plasma so as to obtain key parameters of the plasma.

The high-temperature-resistant lens adopts a quartz material, the melting point of the quartz material is 1750 ℃, and the high-temperature-resistant lens can stably work for a long time when the temperature is lower than 1100 ℃, so that the practical verification is carried out on the introduction of a new material of a focusing antenna. The focusing lens antenna is processed and tested by combining with CST 2018 simulation design through theoretical calculation, and test results show that the focal spot of the lens antenna is smaller than 22mm at the frequency of 30GHz, so that the diagnosis requirement of plasma transmission is met.

drawings

FIG. 1 is a schematic structural diagram of a high temperature plasma diagnostic technique, high temperature resistant focusing lens antenna provided in an embodiment of the present invention;

In the figure: (a) the integral structure of the high-temperature resistant focusing lens antenna is formed into a diagram; (b) the structure of the high-temperature resistant lens is formed into a figure; (c) the structure of the horn feed source is formed into a diagram.

FIG. 2 is a structural dimension diagram of a high temperature resistant focusing lens antenna provided by an embodiment of the invention;

In the figure: (a) the overall structure size of the high-temperature resistant lens antenna is shown; (b) marking the size of the high-temperature resistant focusing lens; (c) hyperbolic relation diagram of lens 1 of the high temperature resistant focusing lens.

fig. 3 is a horn feed source simulation directional diagram provided by the embodiment of the present invention.

fig. 4 is a simulation distribution diagram of the whole simulation S11 curve and the three-dimensional electric field of the high temperature resistant focusing lens antenna provided by the embodiment of the present invention;

In the figure: (a) a high temperature resistant focusing lens antenna S11 simulation curve; (b) a three-dimensional simulated electric field distribution diagram of the high-temperature-resistant focusing lens antenna along the propagation direction; (c) and (3) an electric field simulation distribution diagram of the high-temperature-resistant focusing lens antenna on a focal plane.

FIG. 5 is a two-dimensional energy distribution plot of a practical measurement at a focal plane of a high temperature resistant focusing lens antenna provided by an embodiment of the present invention;

In the figure: (a) the energy distribution diagram of the high-temperature-resistant focusing lens antenna in the plane where the focal point is located along the direction of the electric field; (b) and the energy distribution diagram of the plane where the focal point of the high-temperature-resistant focusing lens antenna is located along the direction of the magnetic field.

in fig. 1: 1. a high temperature resistant focusing lens; 1-1, lens 1; 1-2, lens 2; 2. a horn feed source; 2-1, a horn part; 2-2, coaxial waveguide conversion; 3. an antenna mount; 3-1, a feed source bracket; 3-2, a lens support; 4. and a balancing weight.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In view of the problems in the prior art, the present invention provides a high temperature resistant focusing lens antenna for high temperature plasma diagnostic technology, and the present invention is described in detail below with reference to the accompanying drawings.

As shown in fig. 1, the high temperature plasma diagnostic technology, high temperature resistant focusing lens antenna provided by the embodiment of the present invention includes: high temperature resistant focusing lens 1, loudspeaker feed 2, antenna boom 3, balancing weight 4.

The high-temperature resistant focusing lens 1 is used for refracting and focusing electromagnetic waves.

And the horn feed source 2 is used for irradiating and feeding the lens antenna with electromagnetic waves.

And the antenna bracket 3 is used for supporting and fixing the high-temperature-resistant focusing lens 1 and the horn feed source 2.

And the balancing weight 4 is used for balancing the weight of the high-temperature-resistant focusing lens 1 and the horn feed source 2.

Furthermore, the high-temperature-resistant focusing lens consists of a first lens and a second lens, wherein the first lens converts spherical waves emitted by the horn feed source into plane waves, and the second lens converts the plane waves into spherical waves and focuses the spherical waves on a required focus;

in a preferred embodiment of the present invention, a high temperature resistant focusing lens 1 for refracting and focusing electromagnetic waves. The lens is made of quartz material, the melting point of the quartz material is 1750 ℃, and the lens can stably work for a long time at a high temperature lower than 1100 ℃. Wherein the high temperature resistant focusing lens 1 is composed of a first lens 1-1 and a second lens 1-2. The first lens 1-1 is used for converting the spherical wave emitted by the horn feed 2 into a plane wave, and the second lens 1-2 is used for converting the plane wave converted by the first lens 1-1 into a spherical wave and focusing the spherical wave at the focus O2.

the curves of the first lens 1-1 and the second lens 1-2 are both hyperbolic curves, wherein the curve of the first lens 1-1 is:

Wherein n is the refractive index of the lens, and the value range of x1 is (0, 22.58 mm).

Wherein the curves of the second lenses 1-2 are:

wherein n is the refractive index of the lens, and the value range of x2 is (0, 14.2 mm).

In a preferred embodiment of the invention, the horn feed 2 is used for illuminating and feeding electromagnetic waves to the horn feed. The horn feed source 2 consists of a horn part 2-1 and a waveguide coaxial conversion 2-2, and the material is copper material and is also selected to adapt to high temperature resistance.

in the preferred embodiment of the present invention, the antenna support 3 is used for supporting the high temperature resistant focusing lens 1 and the horn feed 2. The antenna support 3 is composed of a lens support 3-1 and a feed source support 3-2, and is made of high-temperature-resistant stainless steel.

In the preferred embodiment of the invention, the balancing weight 4 is used for balancing the weight of the high-temperature-resistant lens and the horn feed source, so that the center of gravity of the whole antenna is near the middle part of the antenna, the safety and convenience of the placement and installation of the antenna are ensured, and the balancing weight is made of high-temperature-resistant stainless steel materials.

As shown in fig. 1 and fig. 2, the high temperature resistant focusing lens antenna of the present invention is optimized to operate at a frequency of 26.5-40GHz, the effective aperture of the focusing lens is 200mm, and the antenna is focused at 350mm in front. The curves of the specific high temperature resistant lens are shown in formulas (1) and (2), and the structural geometric dimension parameters are shown in table 1.

TABLE 1 geometric dimensions of high temperature resistant focusing lens antenna structures

The technical effects of the present invention will be described in detail with reference to simulations.

The high-temperature resistant focusing lens antenna disclosed by the invention is modeled, simulated and optimized by using commercial simulation software CST 2018, and the simulation result is shown in figures 3-5. Fig. 3 is a simulated directivity pattern of a horn feed. The design of the horn feed source has a very important influence on the radiation efficiency of the lens. The lens antenna belongs to a transmission type antenna, and can refer to the design of a reflector antenna feed source, so the irradiation level of the feed source needs to be considered in detail. In view of the radiation efficiency, the illumination level of the horn feed is designed to be reduced by-9 dB, as shown in fig. 3.

The focusing performance of the high-temperature resistant lens antenna is the most important parameter, so that a simulation result of the focusing performance is provided in simulation software. Fig. 4(a) is a simulation curve of the reflection coefficient of the whole antenna, and from the simulation result, the reflection of the antenna is small in the frequency band range of 26.5-40GHz of the whole frequency band, and the electromagnetic wave signal is basically radiated completely. Fig. 4(b) is a three-dimensional simulated electric field distribution diagram with a frequency of 30GHz, and from the simulation result, the electromagnetic wave forms obvious focusing at a position 350mm away from the lens, which is quite consistent with the theoretical calculation. Fig. 4(c) is a two-dimensional simulated electric field distribution diagram with a frequency of 30GHz on a focal plane, and from the simulation result, the electromagnetic wave forms a very obvious focus on the focal plane, the electric field is very strong at the center, and the energy of the electric field around rapidly decreases.

the high-temperature resistant lens antenna is verified in the simulation of good focusing performance, and in order to verify the effectiveness of theoretical calculation and simulation, the lens antenna is verified by processing test. Fig. 5 is a test of focusing performance performed on the focal plane of the lens. Fig. 5(a) is an energy distribution diagram measured along the electric field direction of the lens antenna on the focal plane, and fig. 5(b) is an energy distribution diagram measured along the magnetic field direction of the lens antenna on the focal plane. From the measurement results, most energy is focused at the center, the focal spot size of the lens is 22mm, namely the 3dB drop point of the energy is limited to the area with the diameter of 22mm, thereby showing that the focusing performance of the lens antenna is very good.

in summary, the invention of the high-temperature resistant focusing lens antenna is subjected to the processes of theoretical calculation, simulation optimization, test verification and the like. In order to adapt to the high temperature resistance of the lens antenna, the lens is made of high temperature resistant quartz material, the melting point of the quartz is 1750 ℃, and the lens can stably work for a long time when the temperature is lower than 1100 ℃. Meanwhile, the horn feed source, the antenna support, the balancing weight and the like are also made of high-temperature-resistant metal materials, so that the high-temperature adaptability of the lens antenna is guaranteed, and the quartz material is used for the first time in the focusing of a millimeter wave frequency band.

In order to improve the effectiveness and the rapidity of design, the design of the high-temperature resistant lens antenna is combined with the simulation of the CST 2018, and through simulation optimization, the focusing lens antenna forms an obvious focusing effect at the position of 350mm of focal length and is quite consistent with theoretical calculation. The antenna is also processed and tested, and the test result shows that the focal spot size of the antenna on a specified focal plane is less than 22mm, and the antenna has better focusing performance than a traditional focusing lens, so that the antenna can more conveniently play a greater role in the transmission of plasma.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.