Waveguide window for W frequency band

Abstract

The invention discloses a waveguide window for a W frequency band, which comprises a waveguide window substrate (1) and a metal cavity (2), a slot is arranged in the metal cavity (2) and is used for forming an air waveguide, the waveguide window substrate (1) is welded on the surface of the metal cavity (2) and is aligned with the slot, and the contact surface of the metal cavity (2) and the waveguide window substrate (1) is subjected to gold plating protection treatment. The surface of the waveguide window substrate (1) is subjected to gold plating protection treatment; the metal cavity (2) is provided with a W-band standard waveguide port, and the waveguide window substrate (1) is provided with a waveguide window opening and a grounding hole. And the waveguide window substrate (1) is welded on the surface of the metal cavity (2) for air tightness. Meanwhile, W signals can be ensured to pass through transmission by adjusting parameters such as the position of a grounding hole and the size of a window of the waveguide window substrate.

Description

Technical Field

[0001] The invention relates to the field of microwave electric vacuum devices, and in particular to a waveguide window used in a W frequency band. Background Art

[0002] As one of the four atmospheric windows with smaller transmission loss in the millimeter wave band, the W band has broad application prospects in the phased array field due to its high frequency, wide frequency band and small loss.

[0003] Waveguide windows are a special window design that uses the principle of waveguides to transmit electromagnetic waves. The design principle of waveguide windows is based on the characteristics of electromagnetic wave transmission in waveguides, and uses specific structures and materials to achieve the transmission and shielding of electromagnetic waves. Waveguide windows are widely used in communications, radar and other fields, and the principle and design of the device are of great significance to the transmission and control of electromagnetic waves. The W band has a higher frequency, and the corresponding circuit structure is small in size, which has very strict requirements on circuit processing, structural processing, assembly process and other aspects.

[0004] At present, with the development of domestic basic devices and the improvement of precision processing technology, W-band related technologies and products are gradually increasing and their applications are becoming more and more extensive. However, there are few designs and researches related to waveguide windows used for W-band signal transmission. Waveguide windows are often used to achieve the airtight design of waveguide ports. By adding specific insulating materials or patterns at the cross-section of the waveguide ports, it can not only ensure the transmission of electromagnetic waves in a specific frequency band, but also make the interface airtight. The applications and products related to the W-band are relatively new technical applications and products in recent years. Considering the high frequency and short wavelength of the W-band, the corresponding circuit structure size is small, and there are very strict requirements on circuit processing, structural processing, assembly process and other aspects. At present, there are few designs related to waveguide windows that can be used in the W-band. Usually, due to the high frequency band, if conventional low-frequency transmission cables such as coaxial cables and microstrip lines are used for W-band signal transmission, the transmission loss will be large. In order to ensure the performance of W-band signal transmission, air waveguide transmission is usually required. However, the air waveguide transmission method causes the interface part of the module to have a waveguide opening, which makes it difficult to achieve airtight packaging. Summary of the invention

[0005] The object of the present invention is to overcome the deficiencies of the prior art and provide a waveguide window for W frequency band.

[0006] The objective of the present invention is achieved through the following technical solutions: The present invention provides a waveguide window for W frequency band, comprising a waveguide window substrate and a metal cavity, wherein the metal cavity is provided with a slot for forming an air waveguide, the waveguide window substrate is welded to the surface of the metal cavity and aligned with the slot, the contact surface between the metal cavity and the waveguide window substrate is subjected to a gold-plated protective treatment, and the surface of the waveguide window substrate is subjected to a gold-plated protective treatment; a W frequency band standard waveguide port is provided on the metal cavity, and a waveguide window opening and a grounding hole are provided on the waveguide window substrate; The window length X1 of the waveguide window opening is in the range of 1.75mm~1.95mm, the window width X2 of the waveguide window opening is in the range of 1.1mm~1.3mm, the operating frequency band of the waveguide window is 88GGHZ~100GHZ, and the window length and window width of the waveguide window opening are adjusted to adapt the waveguide window to different operating frequency bands. The grounding holes are arranged around the waveguide window opening, and the distance X3 from the grounding hole at the long side of the waveguide window opening to the center of the waveguide window opening is in the range of 0.9mm~1.1mm, and the distance X4 from the grounding hole at the wide side of the waveguide window opening to the center of the waveguide window opening is in the range of 1.25mm~1.45mm. The distance between the grounding hole and the center of the waveguide window opening is adjusted to adjust the transmission impedance matching.

[0007] Furthermore, when the waveguide window substrate is welded, the waveguide window substrate and the metal cavity are first cleaned with an ultrasonic cleaner, and then preheated on a 200°C heating table. After reaching 175°C, they are placed on a 235°C heating table, and welded using a welding piece of the same size as the waveguide window substrate, the material of the welding piece being SA305. After the sintered sample is melted, it is removed and cooled naturally.

[0008] Furthermore, the material of the waveguide window substrate is ROGERS5880 with a thickness of 0.127 mm.

[0009] Furthermore, the material of the metal cavity is aluminum alloy 6061-T6.

[0010] Furthermore, the waveguide window and the waveguide interface perform dual-port transmission, the waveguide model of the waveguide interface is BJ900, the transmission loss of the waveguide window in the 88-100Ghz working frequency band is less than 0.01dB, and the port reflection coefficient is less than -28dB.

[0011] The beneficial effects of the present invention are: 1) The present invention has a simple structure, low requirements for processing and assembly processes, and is easy to implement. It also solves the problem of airtight design of air waveguides for W-band signal transmission. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of the structure of a waveguide window for W frequency band according to an embodiment of the present invention; Figure 2 1 is a three-view diagram of a waveguide window for W-band according to an embodiment of the present invention, wherein (a) is a front view, (b) is a side view, and (c) is a bottom view; Figure 3 A schematic diagram of the size of a waveguide window opening of a waveguide window substrate according to an embodiment of the present invention; Figure 4 Schematic diagram of the ground hole spacing of the waveguide window substrate according to an embodiment of the present invention; Figure 5 A schematic diagram of the connection between a waveguide window according to an embodiment of the present invention and a waveguide interface having a waveguide model of BJ900; Figure 6 This is a test result diagram of the connection between the waveguide window of an embodiment of the present invention and the waveguide interface of the waveguide model BJ900; In the figure, 1-waveguide window substrate, 2-metal cavity. DETAILED DESCRIPTION

[0013] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0014] The present invention provides a waveguide window for W frequency band, comprising a waveguide window substrate 1 and a metal cavity 2, the structural schematic diagram of which is shown in FIG. Figure 1 As shown, the metal cavity 2 is provided with a slot inside for forming an air waveguide, the waveguide window substrate 1 is welded to the surface of the metal cavity 2 and aligned with the slot, the contact surface of the metal cavity 2 and the waveguide window substrate 1 is subjected to a gold-plated protection treatment, and the surface of the waveguide window substrate 1 is subjected to a gold-plated protection treatment; the metal cavity 2 is provided with a W-band standard waveguide port, and the waveguide window substrate 1 is provided with a waveguide window opening and a grounding hole, and its three-view drawing is as shown in FIG. Figure 2 As shown, (a) is a front schematic diagram, (b) is a side schematic diagram, and (c) is a bottom schematic diagram.

[0015] Specifically, the window length X1 of the waveguide window opening is in the range of 1.75 mm to 1.95 mm, the window width X2 of the waveguide window opening is in the range of 1.1 mm to 1.3 mm, the operating frequency band of the waveguide window is 88 GGHZ to 100 GHZ, and the size schematic diagram of the waveguide window opening is as shown in Figure 3As shown, by adjusting the window length and window width of the waveguide window opening, the waveguide window is adapted to different working frequency bands. The grounding holes are arranged around the waveguide window opening. The distance X3 between the grounding hole at the long side of the waveguide window opening and the center of the waveguide window opening is in the range of 0.9mm~1.1mm, and the distance X4 between the grounding hole at the wide side of the waveguide window opening and the center of the waveguide window opening is in the range of 1.25mm~1.45mm. The distance between the grounding hole and the center of the waveguide window opening is adjusted to adjust the transmission impedance matching. The schematic diagram of the grounding hole spacing is shown in Figure 4 shown.

[0016] For example, when the waveguide window substrate 1 is welded, the waveguide window substrate 1 and the metal cavity 2 are first cleaned with an ultrasonic cleaner. The welding is performed on a heating table, and two heating tables are required. The waveguide window substrate 1 and the metal cavity 2 are then preheated on a 200°C heating table. After reaching 175°C, they are placed on a 235°C heating table. A welding piece of the same size as the waveguide window substrate is used for welding. The material of the welding piece is SA305. After the sintered sample is melted, it is removed and cooled naturally. After welding is completed, an airtight leak test can be performed, and the test leak rate can reach The material of the waveguide window substrate 1 is ROGERS5880 with a thickness of 0.127 mm. The material of the metal cavity 2 is aluminum alloy 6061-T6.

[0017] For example, the present invention is subjected to a simulation experiment, and the simulation model schematic diagram is shown in FIG. Figure 5 As shown, during the simulation, an external standard waveguide interface is brought in, the waveguide model is BJ900, PORT1 in the figure is the external standard waveguide interface, PORT2 is the waveguide window described in the present invention, and then a dual-port transmission characteristic simulation is performed. The result of the simulation design is shown in FIG. Figure 6As shown, through the surface simulation of three-dimensional electromagnetic simulation software, the designed waveguide window has a transmission loss of less than 0.01dB in the 88-100Ghz working frequency band, and the port reflection coefficient is less than -28dB. It has good transmission characteristics. The present invention is composed of a structural member with a W-band standard waveguide (2.54mm*1.27mm) opening and a waveguide window substrate. By welding the waveguide window substrate to the structural member, the airtight design of the waveguide opening is achieved. The waveguide structural member is a commonly used aluminum alloy 6061-T6 material, and the contact surface with the waveguide window substrate needs to be gold-plated. The waveguide window substrate is made of ROGERS5880 with a thickness of 0.127mm. The front and back graphics are the same, and the surface is gold-plated. As described in the background technology, under normal circumstances, W-band signal transmission adopts the form of air waveguide, and the waveguide opening is difficult to achieve airtightness, so the present invention designs a waveguide window substrate. At the same time, by adjusting the ground hole position of the waveguide window substrate, the size of the window and other parameters, the electromagnetic field three-dimensional modeling simulation design can be carried out to ensure the transmission of the W signal. And because the selected waveguide window substrate material is ROGERS5880, it has a lower dielectric constant and loss tangent, which can minimize the transmission loss. The present invention is an airtight design for W-band waveguide transmission, with a simple structure, low assembly and processing requirements, and is easy to implement.

[0018] The above is only a preferred embodiment of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall not deviate from the spirit and scope of the present invention, and shall be within the scope of protection of the claims attached to the present invention.

Claims

1. A waveguide window for W-band, characterized in that: It comprises a waveguide window substrate (1) and a metal cavity (2), wherein the metal cavity (2) is provided with a slot for forming an air waveguide, the waveguide window substrate (1) is welded to the surface of the metal cavity (2) and aligned with the slot, the contact surface between the metal cavity (2) and the waveguide window substrate (1) is subjected to a gold-plated protective treatment, and the surface of the waveguide window substrate (1) is subjected to a gold-plated protective treatment; the metal cavity (2) is provided with a W-band standard waveguide port, and the waveguide window substrate (1) is provided with a waveguide window opening and a grounding hole; The window length X1 of the waveguide window opening is in the range of 1.75mm~1.95mm, the window width X2 of the waveguide window opening is in the range of 1.1mm~1.3mm, the operating frequency band of the waveguide window is 88GGHZ~100GHZ, and the window length and window width of the waveguide window opening are adjusted to adapt the waveguide window to different operating frequency bands. The grounding holes are arranged around the waveguide window opening, and the distance X3 between the grounding holes at the long sides of the waveguide window opening and the center of the waveguide window opening is in the range of 0.9mm~1.1mm, and the distance X4 between the grounding holes at the wide sides of the waveguide window opening and the center of the waveguide window opening is in the range of 1.25mm~1.45mm. The distance between the grounding holes and the center of the waveguide window opening is adjusted to adjust the transmission impedance matching.

2. A waveguide window for W frequency band according to claim 1, characterized in that: When the waveguide window substrate (1) is welded, the waveguide window substrate (1) and the metal cavity (2) are first cleaned using an ultrasonic cleaning machine, and then the waveguide window substrate (1) and the metal cavity (2) are preheated on a 200°C heating table. After reaching 175°C, they are placed on a 235°C heating table, and welded using a welding piece of the same size as the waveguide window substrate, wherein the material of the welding piece is SA305. After the sintered sample is melted, it is removed and cooled naturally.

3. A waveguide window for W frequency band according to claim 1, characterized in that: The material of the waveguide window substrate (1) is ROGERS5880 with a thickness of 0.127 mm.

4. A waveguide window for W-band according to claim 1, characterized in that: The material of the metal cavity (2) is aluminum alloy 6061-T6.

5. A waveguide window for W-band according to claim 1, characterized in that: The waveguide window and the waveguide interface perform dual-port transmission. The waveguide model of the waveguide interface is BJ900. The transmission loss of the waveguide window in the 88-100Ghz working frequency band is less than 0.01dB, and the port reflection coefficient is less than -28dB.

Images