CN212908063U

CN212908063U - Duplex antenna radio frequency board, antenna structure and antenna system of level meter

Info

Publication number: CN212908063U
Application number: CN202021159040.8U
Authority: CN
Inventors: 付国盛
Original assignee: Beijing Weidu Xinzhi Technology Co ltd
Current assignee: Beijing Weidu Xinzhi Technology Co ltd
Priority date: 2020-06-19
Filing date: 2020-06-19
Publication date: 2021-04-06
Anticipated expiration: 2030-06-19

Abstract

The utility model discloses a level meter duplex antenna radio frequency board, an antenna structure and an antenna system, which comprises a signal transmission layer, a receiving port and a transmitting port; the first metal ground layer is arranged above the signal transmission layer and is respectively provided with a first etching part and a second etching part; the second metal stratum is arranged below the signal transmission layer; the insulating layer is arranged among the signal transmission layer, the first metal stratum and the second metal stratum; a plurality of metal vias disposed along edges of the receive port, the transmit port, the stripline, the first etched portion, and the second etched portion; and the mode converter probes are arranged on the signal transmission layer, are respectively positioned in the third etching part and the fourth etching part and are respectively connected with the receiving port and the transmitting port through corresponding strip lines. The electromagnetic wave transmission structure is converted from a plane structure into a three-dimensional structure, and the distance between a radio frequency device on the radio frequency plate of the material level meter antenna and a high-temperature environment is prolonged, so that the high-temperature resistant requirement of a material level meter antenna system is met.

Description

Duplex antenna radio frequency board, antenna structure and antenna system of level meter

Technical Field

The utility model relates to a level meter measurement technical field, in particular to level meter duplex antenna radio frequency board, antenna structure and antenna system.

Background

In recent years, the level meter measuring technology is widely applied to the industrial production fields of petroleum, chemical engineering, buildings, mines and the like, and has very important significance for improving the product quality, optimizing the process control and realizing the environmental protection. With the acceleration of automation processes, the demand of large related enterprises for level meters is increasing. The level meter is a contact level meter and a non-contact level meter, wherein the contact level meter has the defects of poor stability, low measurement precision, single application scene and the like, and the non-contact level meter is mostly an antenna type radar level meter and has the advantages of high measurement precision, capability of meeting the use requirement of a large tank body, flexible installation, good maintainability and the like, so the level meter is widely applied in industrial production. The most widely applied technology is Frequency Modulation Continuous Wave (FMCW) radar. Compared with a pulse radar system, the frequency modulation continuous wave radar has the characteristics of no distance blind area, high receiving sensitivity, strong anti-interference capability, high resolution, low power requirement, simple structure and the like, and is more and more emphasized.

The FMCW radar level gauge also has higher requirements on an antenna system, the system is required to have the requirements of a wide frequency band, high gain, low side lobe and the like, and in the aspect of environmental adaptability, the high temperature environment is always a difficult problem for limiting the use of the radar level gauge. How to design a high-temperature-resistant high-performance level meter product is a difficult problem which is solved by level meter designers.

SUMMERY OF THE UTILITY MODEL

The utility model discloses aim at solving one of the technical problem that exists among the prior art at least. Therefore, the utility model provides a level meter duplex antenna radio frequency board, antenna structure and antenna system can pass through the electromagnetic wave along the transmission of plane stripline to the wave guide to realize that the electromagnetic wave transmission structure converts the spatial structure into by planar structure, with the high temperature resistant requirement that satisfies level meter antenna system.

In a first aspect, the duplex antenna radio frequency board for the level meter according to the embodiment of the present invention comprises a signal transmission layer, which is provided with a receiving port and a transmitting port, wherein both the receiving port and the transmitting port are connected with a strip line; the first metal ground layer is arranged above the signal transmission layer, and a first etching part and a second etching part which are used as mode converter interfaces are respectively arranged on the first metal ground layer; a second metal ground layer disposed below the signal transmission layer; an insulating layer disposed between the signal transmission layer, the first metal formation, and the second metal formation; a plurality of metal vias disposed along edges of the receiving port, the transmitting port, the strip line, the first etched portion, and the second etched portion and respectively connected to the first metal ground layer and the second metal ground layer; and mode converter probes arranged on the signal transmission layer and respectively located in a third etching part and a fourth etching part, wherein the third etching part and the fourth etching part are respectively matched with the first etching part and the second etching part, and the mode converter probes are respectively connected with the receiving port and the transmitting port through the corresponding strip lines.

According to some embodiments of the present invention, the signal transmission layer and the second metal layer are further provided with a third metal layer therebetween, and the third metal layer is provided with a fifth etching portion corresponding to the receiving port, the transmitting port and the strip line.

In a second aspect, the duplex antenna structure of the level meter according to the embodiment of the present invention comprises a waveguide and the duplex antenna rf plate of the level meter, wherein the waveguide is connected to the mode converter interface.

According to some embodiments of the invention, the waveguide is kept away from one end of the level meter duplex antenna radio frequency board is provided with a feed horn.

According to some embodiments of the present invention, the feed horn is a smooth-walled horn, a corrugated horn, a plug-type horn, or a circular waveguide horn.

According to some embodiments of the invention, the waveguide is a circular waveguide or a rectangular waveguide with a double channel.

According to some embodiments of the utility model, the outside of waveguide pipe is provided with the metal casing, install the lens antenna on the metal casing, the lens antenna is located keeping away from of waveguide pipe the one end of level meter duplex antenna radio frequency board, just the lens antenna with be provided with the clearance between the waveguide pipe.

According to some embodiments of the invention, the lens antenna is made of Polytetrafluoroethylene (PTFE), polybutylene terephthalate (PBT) or polypropylene (PP).

Third aspect, according to the utility model discloses level meter duplex antenna system, including showing accuse module, signal processing and power module and foretell level meter duplex antenna structure, install driver chip on the level meter duplex antenna radio-frequency board, driver chip respectively with the receiving port with the transmission port is connected, show accuse module with level meter duplex antenna radio-frequency board electricity respectively connect in signal processing and power module.

According to the utility model discloses one or more technical scheme have following beneficial effect at least: when the electromagnetic wave transmission structure is used, the mode conversion interface is connected with the waveguide tube, the receiving port and the transmitting port are separated to avoid interference of a transmitting signal on the receiving signal, the mode converter probe radiates electromagnetic waves to a second metal stratum to form reflected waves, the reflected waves and incident waves are subjected to vector superposition to form good matching, reactance contributed by a high-order falling mode is counteracted, and incident power is completely coupled into the waveguide tube, so that the purpose of transferring electromagnetic waves transmitted along a plane strip line into the waveguide tube is achieved, the electromagnetic wave transmission structure is converted from a plane structure into a three-dimensional structure, the distance between the level meter antenna radio frequency plate and a high-temperature environment can be prolonged by selecting the waveguide tube with a proper length, the influence of the high-temperature environment on circuit devices on the level meter antenna radio frequency plate is reduced, and the high-temperature requirement of the level.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is an exploded view of a duplex antenna RF plate of a level meter according to an embodiment of the present invention;

FIG. 2 is a schematic top perspective view of the duplex antenna RF plate of the level gauge shown in FIG. 1;

FIG. 3 is a schematic cross-sectional view of a duplex antenna RF structure of a level meter according to an embodiment of the present invention;

FIG. 4 is a schematic cross-sectional view of a duplex antenna RF structure of a level meter according to an embodiment of the present invention;

fig. 5 is a schematic cross-sectional structure diagram of a duplex antenna rf system of a level meter according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present invention, and should not be construed as limiting the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, a plurality of means are one or more, a plurality of means are two or more, and the terms greater than, less than, exceeding, etc. are understood as not including the number, and the terms greater than, less than, within, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless there is an explicit limitation, the words such as setting, installation, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in combination with the specific contents of the technical solution.

Referring to fig. 1, the present embodiment discloses a duplex antenna rf board 100 for a level gauge, which includes a signal transmission layer 110, a first metal ground layer 120, a second metal ground layer 130, an insulating layer 140, and a plurality of metal vias 150, wherein the signal transmission layer 110 is provided with a receiving port 111a and a transmitting port 111b, and the receiving port 111a and the transmitting port 111b of the present embodiment are separately arranged, so as to avoid interference of a transmitting signal with a receiving signal, and have a high transmit-receive isolation.

The first metal ground layer 120 is disposed above the signal transmission layer 110, the first metal ground layer 120 is provided with a first etching portion 121a and a second etching portion 121b serving as mode converter interfaces, the number of the mode converter interfaces is two, the mode converter interfaces are respectively used for receiving signals and transmitting signals, the second metal ground layer 130 is disposed below the signal transmission layer 110, the insulating layer 140 is disposed between the signal transmission layer 110, the first metal ground layer 120 and the second metal ground layer 130, the metal via holes 150 are disposed along the edges of the first etching portion 121a, the second etching portion 121b and the strip line 112 and are respectively connected to the first metal ground layer 120 and the second metal ground layer 130, and by adjusting the spacing between adjacent metal via holes 150, ideal electrical wall conditions can be achieved, electromagnetic wave transmission along the tangential direction of the electrical wall can be realized, and the first metal ground layer 120 and the second metal ground layer 130 are matched, the transmission direction of electromagnetic waves can be bound, the electromagnetic loss can be prevented, the loss can be reduced, the surface wave interference of the duplex antenna radio-frequency board 100 of the level meter can be reduced, and the anti-interference capability can be improved.

Referring to fig. 1 and 2, the signal transmission layer 110 is further provided with two mode converter probes 160, the two mode converter probes 160 are respectively located in the third etching portion 113a and the fourth etching portion 113b, the third etching portion 113a and the fourth etching portion 113b are both disposed on the signal transmission layer 110, and have sizes and positions corresponding to the first etching portion 121a and the second etching portion 121b, respectively, and the two mode converter probes 160 are respectively connected to the receiving port 111a and the transmitting port 111b through the corresponding strip lines 112. When in use, the two mode converter interfaces are respectively connected with the waveguide 210, the electromagnetic wave is respectively transmitted to the mode converter probes 160 of the receiving port 111a and the transmitting port 111b through the strip line 112 of the signal transmission layer 110, the mode converter probes 160 radiate the electromagnetic wave to the second metal ground layer 130 to form a reflected wave, the reflected wave and the incident wave are vector-superposed to form a good matching, the reactance contributed by a high-order fading mode is counteracted, the incident power is fully coupled into the waveguide 210, the purpose of transferring the electromagnetic wave transmitted along the plane strip line 112 to the waveguide 210 is achieved, thereby realizing that the electromagnetic wave transmission structure is converted from a plane structure to a three-dimensional structure, by selecting the waveguide 210 with a proper length, the distance between the level meter duplex antenna radio frequency board 100 and a high-temperature environment can be prolonged, and the influence of the high-temperature environment on circuit devices on the level meter duplex antenna radio frequency, so as to meet the high temperature resistance requirement of the duplex antenna system of the level meter.

In some embodiments, the duplex antenna rf board 100 for the level gauge may be formed by laminating a copper-clad plate, a prepreg and a copper foil, wherein the substrate layer of the copper-clad plate and the prepreg layer after lamination are both the insulating layer 140. By selecting a material with a proper thickness, 1/4 with the equivalent distance between the mode converter probe 160 and the second metal ground layer 130 as the wavelength is realized, and reasonable impedance matching is performed, so that a short-circuit metal piece additionally added at the bottom of the duplex antenna radio-frequency board 100 of the level meter can be omitted, the production efficiency is improved, the distance resolution and the sensitivity of the radar are prevented from being influenced by the processing precision and the assembly tolerance of the short-circuit metal piece, and the reliability of the product is improved.

Referring to fig. 1, in other embodiments, the duplex antenna rf board 100 of the level meter is formed by laminating an upper copper-clad plate and a lower copper-clad plate, and a prepreg positioned between the two copper-clad plates, so that a third metal ground layer 170 is further disposed between the signal transmission layer 110 and the second metal ground layer 130, and a fifth etching portion 171 corresponding to the receiving port 111a, the transmitting port 111b, and the strip line 112 is disposed on the third metal ground layer 170. In operation, the electromagnetic wave radiated by the mode converter probe 160 passes through the third metal ground layer 170 from the fifth etching portion 171 corresponding to the third etching portion 113a or the fourth etching portion 113b, and then reaches the second metal ground layer 130, and is emitted through the second metal ground layer 130 to form a reflected wave, and the reflected wave and the incident wave vector are superimposed to form a good match, so as to cancel the reactance contributed by the higher order mode, and thus, the incident power is completely coupled into the waveguide. It is understood that the first etched portion 121a, the second etched portion 121b, the third etched portion 113a, the fourth etched portion 113b and the fifth etched portion 171 may be obtained by etching a copper sheet at the time of PCB production. By adjusting the port impedance of the modal converter probe 160 and the length of the modal converter probe 160 within the third etched portion 113a or the fourth etched portion 113b, adjustment of the mode matching can be achieved, thereby achieving good electrical performance.

Referring to fig. 3, the present invention further discloses a duplex antenna structure of a level meter, including a waveguide 210 and the duplex antenna rf board 100 of the level meter, wherein the waveguide 210 is connected to a mode converter interface, and the size of the inner wall of the waveguide 210 is the same as the size of the mode converter interface, so as to avoid electromagnetic wave leakage. The level meter duplex antenna radio-frequency board 100 transfers the electromagnetic waves transmitted by the planar strip line 112 to the waveguide tube 210, so that the electromagnetic wave transmission structure is converted from a planar structure into a three-dimensional structure, the distance between the level meter duplex antenna radio-frequency board 100 and a high-temperature environment can be prolonged by selecting the waveguide tube 210 with a proper length, the influence of the high-temperature environment on circuit devices on the level meter duplex antenna radio-frequency board 100 is reduced, and the high-temperature resistant requirement of the level meter duplex antenna system is met.

In some embodiments, the waveguide 210 with an opening is selected as a receiving and transmitting feed source according to performance requirements, in other embodiments, a feed source horn (not shown) is arranged at one end of the waveguide 210 away from the level meter duplex antenna radio-frequency board 100, and the feed source horn is used as the receiving and transmitting feed source, specifically, the feed source horn adopts a light wall horn, a corrugated horn, a plug-type horn or a circular waveguide horn.

Referring to fig. 3, in some embodiments, the waveguide 210 may be two independent waveguides 210, and the two waveguides 210 are respectively connected to two mode converter interfaces for receiving and transmitting signals, and in other embodiments, the waveguide 210 may be a circular waveguide or a rectangular waveguide having two channels, that is, two parallel electromagnetic wave transmission channels are provided in the same waveguide 210, so that the structure is compact, and the number of assembling parts is reduced.

Referring to fig. 4, a metal housing 230 is disposed outside the waveguide 210, a lens antenna 240 is mounted on the metal housing 230, the lens antenna 240 is located at an end of the waveguide 210 away from the level meter duplex antenna rf board 100, and a gap 241 is disposed between the lens antenna 240 and the waveguide 210. In the present embodiment, by using the characteristics that the lens antenna 240 deviates from the focal point, which does not cause large gain drop and large main beam angle deviation, the waveguide 210 for receiving signals and the waveguide 210 for transmitting signals share the lens antenna 240, and through the good taper matching between the waveguide 210 and the lens antenna 240, the radiation efficiency of 65% and the excellent performance of 35dB antenna transmit-receive isolation can be achieved. A gap 231 is further disposed between the metal housing 230 and the waveguide 210, and the waveguide 210 exchanges heat with external cold air through the gap 231, thereby achieving the purpose of heat dissipation.

The lens antenna 240 is made of Polytetrafluoroethylene (PTFE), polybutylene terephthalate (PBT) or polypropylene (PP). The lens antenna 240 made of teflon has a high temperature resistance, and can work in a high temperature environment of 250 ℃.

Referring to fig. 5, the present invention further discloses a level meter duplex antenna system, including a display control module 310, a signal processing and power supply module 320 and the level meter duplex antenna structure, a driving chip is installed on the level meter duplex antenna rf board 100, the driving chip can adopt the existing Monolithic Microwave Integrated Circuit (MMIC) chip in the market, the driving chip is respectively connected with the receiving port 111a and the transmitting port 111b of the level meter duplex antenna rf board 100, the display control module 310 and the level meter duplex antenna rf board 100 are respectively electrically connected to the signal processing and power supply module 320, wherein the display control module 310 and the signal processing and power supply module 320 can both adopt the existing Integrated module. The band of the duplex antenna system of the level meter of the embodiment belongs to the W band, and the driving chip of the W band has the advantage of small volume, and the dual-antenna feed source does not occupy the area of the radio frequency board 100 of the duplex antenna of the level meter too much.

Referring to fig. 1 to 5, in use, the receiving port 111a and the transmitting port 111b are separated to avoid interference of the transmitting signal with the receiving signal, the mode converter probe 160 radiates the electromagnetic wave to the second metal ground layer 130 to form a reflected wave, the reflected wave and the incident wave are vector-superposed to form a good match, and a reactance contributed by a higher order withering mode is cancelled, so that the incident power is fully coupled into the waveguide 210, and the purpose of transferring the electromagnetic wave transmitted along the planar strip line 112 to the waveguide 210 is achieved, thereby realizing that the electromagnetic wave transmission structure is converted from a planar structure to a three-dimensional structure, and by selecting the waveguide 210 with a proper length, the distance between the electrical parts such as the level meter antenna rf board, the display and control module 310, and the signal processing and power supply module 320 and the high temperature environment can be extended, and the influence of the high temperature environment on the circuit devices on the level, so as to meet the high temperature resistance requirement of the antenna system of the level meter.

The embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention within the knowledge of those skilled in the art.

Claims

1. A duplex antenna radio frequency board (100) for a level gauge, comprising:

the signal transmission layer (110) is provided with a receiving port (111a) and a transmitting port (111b), and the receiving port (111a) and the transmitting port (111b) are connected with a strip line (112);

a first metal ground layer (120) disposed above the signal transmission layer (110), the first metal ground layer (120) having a first etched portion (121a) and a second etched portion (121b) disposed thereon, respectively, to serve as mode converter interfaces;

a second metal ground layer (130) disposed below the signal transmission layer (110);

an insulating layer (140) disposed between the signal transmission layer (110), the first metal formation (120), and the second metal formation (130);

a plurality of metal vias (150) disposed along edges of the receiving port (111a), the transmitting port (111b), the strip line (112), the first etched portion (121a), and the second etched portion (121b), and connected to the first metal ground layer (120) and the second metal ground layer (130), respectively;

and mode converter probes (160) disposed on the signal transmission layer (110) and respectively located in a third etched portion (113a) and a fourth etched portion (113b), the third etched portion (113a) and the fourth etched portion (113b) respectively fitting the first etched portion (121a) and the second etched portion (121b), the mode converter probes (160) respectively connected to the receiving port (111a) and the transmitting port (111b) through the corresponding strip lines (112).

2. The level gauge duplex antenna radio frequency board (100) according to claim 1, wherein a third metal ground layer (170) is further disposed between the signal transmission layer (110) and the second metal ground layer (130), and a fifth etching portion (171) corresponding to the receiving port (111a), the transmitting port (111b) and the strip line (112) is disposed on the third metal ground layer (170).

3. A level gauge duplex antenna structure, characterized in that it comprises a waveguide (210) and a level gauge duplex antenna radio frequency plate (100) according to claim 1 or 2, said waveguide (210) being interfaced with said mode converter.

4. The level gauge duplex antenna structure according to claim 3, characterized in that the end of the waveguide (210) away from the level gauge duplex antenna radio frequency plate (100) is provided with a feed horn.

5. A level gauge duplex antenna structure as defined in claim 4 wherein said feed horn is an optical wall horn, a corrugated horn, a plug-type horn or a circular waveguide horn.

6. Level gauge duplex antenna structure according to one of claims 3 to 5, characterized in that the waveguide (210) is a circular or rectangular waveguide with a double channel.

7. Level gauge duplex antenna structure according to any of claims 3 to 5, characterized in that a metal housing (230) is arranged outside the waveguide (210), a lens antenna (240) is mounted on the metal housing (230), the lens antenna (240) is located at one end of the waveguide (210) far away from the level gauge duplex antenna radio frequency plate (100), and a gap (241) is arranged between the lens antenna (240) and the waveguide (210).

8. Level gauge duplex antenna structure according to claim 7, characterized in that the lens antenna (240) is made of Polytetrafluoroethylene (PTFE), polybutylene terephthalate (PBT) or polypropylene (PP).

9. A level meter duplex antenna system, which is characterized by comprising a display and control module (310), a signal processing and power supply module (320) and the level meter duplex antenna structure as claimed in any one of claims 4 to 8, wherein a driving chip is mounted on the level meter duplex antenna RF board (100), the driving chip is respectively connected with the receiving port (111a) and the transmitting port (111b), and the display and control module (310) and the level meter duplex antenna RF board (100) are respectively and electrically connected with the signal processing and power supply module (320).