Microstrip-to-waveguide transmission device and communication equipment

Abstract

The embodiment of the invention discloses a microstrip-to-waveguide transmission device and communication equipment. According to the microstrip-to-waveguide transmission device with polarization torsion provided by the embodiment of the invention, the problems that the transition structure from the microstrip to the waveguide is not compact enough and the size is relatively large in the scene that a waveguide transmission channel is vertical to the microstrip line in the prior art are solved. The microstrip line has the advantages of simple structure, low loss and no increase of the longitudinal distance of the waveguide, can realize the purpose that the microstrip line is parallel to the transmission direction of the waveguide H surface in a waveguide size range, and can be widely applied to compact microwave and millimeter wave circuit design.

Description

Technical Field

[0001] The embodiments of the present application relate to the field of electronic technology, and in particular to a microstrip-to-waveguide transmission device and a communication device. Background Art

[0002] Waveguide and microstrip are two important transmission lines in electromagnetic field and microwave engineering. Waveguide transmission line has the advantages of low transmission loss and high power capacity; microstrip transmission line has the advantages of small size, light weight, and easy planar integration. There are a large number of microwave devices based on these two transmission lines in microwave systems. Due to the different electromagnetic field propagation modes in these two transmission lines, the two cannot be integrated together by simple connection. The waveguide-microstrip transition can convert the TE10 mode in the waveguide transmission line into the quasi-TEM mode in the microstrip transmission line, and is a bridge connecting waveguide circuits and microstrip circuits.

[0003] The commonly used microstrip waveguide transition structures at present include microstrip probe waveguide transition. Among these transition structures, the microstrip probe waveguide transition structure has the advantages of simple structure and high coupling efficiency and is widely used. In the existing microstrip waveguide transition products, the microstrip line and the H-plane of the waveguide are usually designed to be perpendicular. This design makes the microstrip line parallel to the long side of the waveguide (i.e., the H-plane) in the transmission direction. When the H-plane of the input waveguide port of the post-stage module and the microstrip line output are parallel, this type of microstrip-to-waveguide transition structure is not applicable. Therefore, the design idea of ​​E-plane probe microstrip waveguide transition is proposed in the industry, so that the microstrip line is parallel to the long side of the waveguide (i.e., the H-plane) in the transmission direction. However, the size of the waveguide in the signal transmission direction of this scheme is long, and the waveguide end needs to increase the distance of at least 1.5 times the long side of the waveguide in the signal transmission direction, which is not conducive to the design and use of compact products in scenarios where the waveguide transmission channel is perpendicular to the microstrip line. Summary of the invention

[0004] The embodiments of the present invention provide a microstrip-to-waveguide transmission device and a communication device to solve the technical problem that the transition structure from microstrip to waveguide is not compact enough in the scenario where the existing waveguide transmission channel is perpendicular to the microstrip line.

[0005] In a first aspect, an embodiment of the present application provides a microstrip-to-waveguide transmission device, which includes a microstrip transmission line, a microstrip-to-waveguide structure, a waveguide matching polarization conversion structure, and a waveguide structure;

[0006] The microstrip probe of the microstrip transmission line extends into the transition waveguide cavity of the microstrip-to-waveguide structure for electromagnetic coupling transmission. The electromagnetic wave signal transmitted by the microstrip transmission line is a TEM mode.

[0007] The lower end of the microstrip-to-waveguide structure is connected to the waveguide structure through a waveguide matching polarization conversion structure;

[0008] The central axis of the input port of the microstrip transmission line and the central axis of the waveguide output port of the waveguide structure are on the same straight line, and the signal transmission direction of the microstrip transmission line is parallel to the wide side of the waveguide structure.

[0009] The microstrip probe is arranged at the bottom of the transition waveguide cavity, the top of the microstrip probe is about 1 / 4 wavelength away from the top of the transition waveguide cavity, and the outer side opposite to the bottom of the transition waveguide cavity is the lower end of the microstrip to waveguide structure.

[0010] The waveguide structure is an input waveguide structure or an output waveguide structure.

[0011] The cross section of the waveguide matching polarization conversion structure at any position is a circle with two intersecting parts and the same radius, and the cross section is parallel to the lower end of the microstrip polarization conversion waveguide structure.

[0012] The diameter of the circle is 4.6 mm, and the height of the waveguide matching polarization conversion structure is 3 mm.

[0013] Among them, the line width of the microstrip transmission line is 0.61mm.

[0014] Among them, the length of the microstrip transmission line extending into the transition waveguide cavity is 1.38 mm.

[0015] The length of the microstrip probe is 0.72 mm and the width is 1.1 mm.

[0016] The length of the transition waveguide cavity is 1.1 mm, the width is 1.6 mm, and the height is 0.85 mm.

[0017] In a second aspect, an embodiment of the present application further provides a communication device, which includes any microstrip to waveguide transmission device of the first aspect.

[0018] As described above, the communication equipment adopts any one of the microstrip-to-waveguide transmission devices in the first aspect, and has corresponding beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is an overall structural diagram of the microstrip-to-waveguide transmission device provided in an embodiment of the present application.

[0020] Figure 2 An overall perspective view of the microstrip-to-waveguide transmission device provided in an embodiment of the present application.

[0021] Figure 3 This is a front view of the microstrip to waveguide transmission device provided in an embodiment of the present application.

[0022] Figure 4 for Figure 3 Cross-section view of AA.

[0023] Figure 5for Figure 3 Cross-section of CC.

[0024] Figure 6 A side view of a microstrip-to-waveguide transmission device provided in an embodiment of the present application.

[0025] Figure 7 for Figure 6 Cross-section of the BB.

[0026] Figure 8 A top view of a microstrip-to-waveguide transmission device provided in an embodiment of the present application.

[0027] Fig. 9 A bottom view of the microstrip-to-waveguide transmission device provided in an embodiment of the present application.

[0028] Fig.10 A schematic diagram of the dimensions of the microstrip transmission line provided in an embodiment of the present application.

[0029] Fig.11 A schematic diagram of the dimensions of the microstrip-to-waveguide structure provided in an embodiment of the present application.

[0030] Fig.12 A schematic diagram of the dimensions of the waveguide matching polarization conversion structure provided in an embodiment of the present application.

[0031] Fig.13 This is a diagram of the transmission effect simulation results of the microstrip-to-waveguide transmission device provided in an embodiment of the present application.

[0032] Among them, 10-microstrip transmission line; 20-microstrip to waveguide structure; 30-waveguide matching polarization conversion structure; 40-waveguide structure. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0034] It should be noted that due to space limitations, this application description does not list all optional implementation methods. After reading this application description, those skilled in the art should be able to understand that as long as the technical features do not contradict each other, any combination of technical features can constitute an optional implementation method.

[0035] The following is a detailed description of the various embodiments of the present invention.

[0036] The inventors analyzed the existing microstrip waveguide transition structures and found that the commonly used microstrip waveguide transition structures include microstrip probe waveguide transition. Among these transition structures, the microstrip probe waveguide transition structure has the advantages of simple structure and high coupling efficiency and is widely used. In the existing microstrip waveguide transition products, the microstrip line and the H-plane of the waveguide are usually designed to be perpendicular. This design makes the microstrip line parallel to the long side of the waveguide (i.e., the H-plane) in the transmission direction. When the H-plane of the input waveguide port of the post-stage module and the microstrip line output are parallel, this type of microstrip-to-waveguide transition structure is not applicable. Therefore, the design idea of ​​E-plane probe microstrip waveguide transition is proposed in the industry, so that the microstrip line is parallel to the long side of the waveguide (i.e., the H-plane) in the transmission direction. However, the size of the waveguide in the signal transmission direction of this scheme is long, and the waveguide end needs to increase the distance of at least 1.5 times the long side of the waveguide in the signal transmission direction, which is not conducive to the design and use of compact products in scenarios where the waveguide transmission channel is perpendicular to the microstrip line.

[0037] In response to the above technical problems, the embodiments of the present application propose a microstrip to waveguide transmission device and communication equipment. The microstrip to waveguide transmission device with polarization twisting proposed in the embodiments of the present application overcomes the problem that the transition structure from microstrip to waveguide is not compact enough and has a large size when the waveguide transmission channel is perpendicular to the microstrip line in the prior art. It has the advantages of simple structure, low loss, and no increase in the longitudinal distance of the waveguide. It can achieve the purpose of transmission in the direction of microstrip line parallel to the H-plane of the waveguide within only one waveguide size range, and can be widely used in compact microwave and millimeter wave circuit design.

[0038] Please refer to Figure 1-Figure 13 , which are respectively an overall structural diagram of the microstrip-to-waveguide transmission device provided in an embodiment of the present application, an overall perspective view of the microstrip-to-waveguide transmission device, a front view of the microstrip-to-waveguide transmission device, Figure 3 Cross-section of AA, Figure 3 Cross-sectional view of CC, side view of microstrip-to-waveguide transmission device, Figure 6 The cross-sectional view of the BB, the top view of the microstrip-to-waveguide transmission device, the bottom view of the microstrip-to-waveguide transmission device, the dimensional schematic diagram of the microstrip transmission line, the dimensional schematic diagram of the microstrip-to-waveguide structure, the dimensional schematic diagram of the waveguide matching polarization conversion structure and the transmission effect simulation result diagram of the microstrip-to-waveguide transmission device.

[0039] As shown in the figure, an embodiment of the present application provides a microstrip to waveguide transmission device, which includes a microstrip transmission line 10, a microstrip to waveguide structure 20, a waveguide matching polarization conversion structure 30, and a waveguide structure 40 (the waveguide structure 40 is an input waveguide structure or an output waveguide structure. The description based on the accompanying drawings exemplarily explains the transmission direction with input as the input. In actual products, it can be used as input or output without specific limitation).

[0040] The microstrip probe of the microstrip transmission line 10 extends into the transition waveguide cavity of the microstrip-to-waveguide structure 20 for electromagnetic coupling transmission, and the electromagnetic wave signal transmitted by the microstrip transmission line 10 is a TEM mode; the lower end of the microstrip-to-waveguide structure 20 is connected to the waveguide structure 40 through a waveguide matching polarization conversion structure 30; the central axis of the input port of the microstrip transmission line 10 and the central axis of the waveguide output port of the waveguide structure 40 are on the same straight line, and the signal transmission direction of the microstrip transmission line 10 is parallel to the wide side of the waveguide structure 40.

[0041] The microstrip transmission line 10 in the embodiment of the present application may be a 50 ohm microstrip line, such as Fig.10 As shown, the line width is 0.61mm and the thickness is 0.254mm. A rectangular waveguide cavity can be used, wherein the rectangular waveguide cavity is 2.5mm high in the vertical direction from the microstrip transmission line 10, and the microstrip transmission line 10 is 1mm away from the ground in the parallel direction. The electromagnetic wave signal transmitted by the microstrip line is a TEM mode; one end of the microstrip transmission line is connected to a microstrip probe, and the other end is connected to the signal input end. Please refer to Fig.10 The design dimensions of the microstrip transmission line 10 are as follows: the line width of the microstrip transmission line 10 is 0.61 mm, the lateral distance between the microstrip transmission line 10 and the ground is 1 mm, that is, the distance between the ground ends on both sides of the microstrip transmission line 10 is 2.61 mm, the length of the microstrip transmission line 10 penetrating into the waveguide cavity is 1.38 mm, the length of the radiation probe of the microstrip transmission line 10 is 0.72 mm, and the width of the radiation probe of the microstrip transmission line 10 is 1.1 mm.

[0042] In a specific implementation, the microstrip probe is arranged at the bottom of the transition waveguide cavity, the top of the microstrip probe is about 1 / 4 wavelength away from the top of the transition waveguide cavity, and the outer side relative to the bottom of the transition waveguide cavity is the lower end of the microstrip to waveguide structure 20. The function of this design is to convert the TEM mode electromagnetic wave transmitted by the microstrip transmission line 10 into the TE mode that can be transmitted by the rectangular waveguide. Its specific working mechanism is that the radiation probe of the microstrip transmission line 10 radiates electromagnetic waves with the same amplitude and a phase difference of 180 degrees in both the upward and downward directions, wherein the electromagnetic wave in the downward direction can be transmitted to the next waveguide almost losslessly, and the electromagnetic wave radiated upward is transmitted to the short-circuit reflection surface with a groove depth of about 1 / 4 wavelength, and is losslessly totally reflected. Because the depth of the short-circuit surface is 1 / 4 wavelength, the phase difference of the one-way path is 90 degrees, and the two-way phase difference reaching the radiation probe after reflection is 180 degrees, which realizes equal amplitude and phase superposition with the electromagnetic wave transmitted downward, and the amplitude reaches the maximum, so as to achieve the purpose of transmitting all signals downward.

[0043] In the specific implementation process, the impedance of the microstrip transmission line 10 port is 50 ohms, the waveguide model can be WR-28 (cross-sectional dimensions: 7.112×3.556 mm), and the detailed parameters of the microstrip to waveguide structure 20 are as follows: Fig.11 As shown, the PCB thickness of the microstrip circuit is 0.254mm, the dielectric constant is 3, and the surface is treated with nickel-gold. The height of the cover plate above the microstrip transmission line 10 is 2.5mm, the height of the cover plate above the radiation probe of the microstrip transmission line 10 is 2.75mm, the length of the transition waveguide cavity is 1.1mm, the height of the transition waveguide cavity is 0.85mm, and the width of the transition waveguide cavity is 1.6mm.

[0044] The cross section of the waveguide matching polarization conversion structure 30 at any position is a circle with two intersecting parts and the same radius, and the cross section is parallel to the lower end of the microstrip waveguide conversion structure. The waveguide matching polarization conversion structure 30 provides a good matching transition for the upper and lower layers of mutually orthogonal waveguides. In this design, it is a columnar structure with two cylindrical parts with a diameter of 4.6mm and a height of 3mm embedded. This matching transition and polarization rotation part can achieve the matching and polarization twisting functions of the upper and lower orthogonal waveguides. The waveguide matching polarization conversion structure is as follows: Fig.12 As shown, the diameter of the circle is 4.6 mm, and the height of the waveguide matching polarization conversion structure 30 is 3 mm.

[0045] For the waveguide structure 40, a standard rectangular waveguide can be used. In the Ka band, a WR28 waveguide is used, the long side of the waveguide is 7.112 mm, and the narrow side is 3.556 mm. For ease of processing, the waveguide is provided with an inner chamfer with a radius of 1.2 mm. It should be noted that the reflection surfaces of the waveguide structure 40 and the microstrip-to-waveguide structure 20 in the present invention are orthogonal at 90 degrees, and the waveguides of the two are orthogonal.

[0046] In general, the microstrip to waveguide transmission device in the embodiment of the present application can realize the conversion of the signal from the microstrip line to the waveguide while realizing the polarization twist of the signal; on the transmission path of the waveguide, in the Ka band, the actual overall area only occupies 7.42x7.24mm, and the size is compact; the matching transition zone waveguide is circular, has good machinability, is conducive to mold casting, and is conducive to ensuring the machining accuracy of the finished product; the transmission loss is small, less than 0.1dB, and the specific simulation results are as follows Fig.13 As shown; it can be easily extended to other frequency bands for use, and has strong scalability.

[0047] The embodiments of the present application further provide a communication device, which includes the microstrip-to-waveguide transmission device in any of the foregoing embodiments and has corresponding technical effects.

[0048] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0049] Note that the above are only preferred embodiments of the present invention and the technical principles used. Those skilled in the art will understand that the present invention is not limited to the specific embodiments herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments, and may include more other equivalent embodiments without departing from the concept of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A microstrip to waveguide transmission device, characterized in that: Including microstrip transmission line, microstrip to waveguide structure, waveguide matching polarization conversion structure, and waveguide structure; The microstrip probe of the microstrip transmission line extends into the transition waveguide cavity of the microstrip-to-waveguide structure for electromagnetic coupling transmission, and the electromagnetic wave signal transmitted by the microstrip transmission line is a TEM mode; The lower end of the microstrip-to-waveguide structure is connected to the waveguide structure through the waveguide matching polarization conversion structure; The central axis of the input port of the microstrip transmission line and the central axis of the waveguide output port of the waveguide structure are on the same straight line, and the signal transmission direction of the microstrip transmission line is parallel to the wide side of the waveguide structure.

2. The microstrip-to-waveguide transmission device according to claim 1, characterized in that: The microstrip probe is arranged at the bottom of the transition waveguide cavity, the top of the microstrip probe is about 1 / 4 wavelength away from the top of the transition waveguide cavity, and the outer side opposite to the bottom of the transition waveguide cavity is the lower end of the microstrip to waveguide structure.

3. The microstrip-to-waveguide transmission device according to claim 1 or 2, characterized in that: The waveguide structure is an input waveguide structure or an output waveguide structure.

4. The microstrip-to-waveguide transmission device according to claim 1, characterized in that: The cross section of the waveguide matching polarization conversion structure at any position is a circle with two intersecting parts and the same radius, and the cross section is parallel to the lower end of the microstrip waveguide conversion structure.

5. The microstrip-to-waveguide transmission device according to claim 4, characterized in that: The diameter of the circle is 4.6 mm, and the height of the waveguide matching polarization conversion structure is 3 mm.

6. The microstrip-to-waveguide transmission device according to claim 1, characterized in that: The line width of the microstrip transmission line is 0.61 mm.

7. The microstrip-to-waveguide transmission device according to claim 1, characterized in that: The length of the microstrip transmission line extending into the transition waveguide cavity is 1.38 mm.

8. The microstrip-to-waveguide transmission device according to claim 1, characterized in that: The length of the microstrip probe is 0.72 mm and the width is 1.1 mm.

9. The microstrip-to-waveguide transmission device according to claim 1, characterized in that: The transition waveguide cavity has a length of 1.1 mm, a width of 1.6 mm, and a height of 0.85 mm.

10. A communication device, characterized in that A microstrip-to-waveguide transmission device comprising the device described in any one of claims 1-9.

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