CN117352980A - Microstrip line-to-waveguide conversion module and microstrip line-to-waveguide broadband conversion method - Google Patents

Abstract

The application relates to a microstrip line-to-waveguide conversion module and a microstrip line-to-waveguide broadband conversion method, wherein the microstrip line-to-waveguide conversion module comprises a microstrip line unit, a conversion unit and a waveguide unit, wherein: the microstrip line unit comprises a microstrip line signal line and a microstrip line ground wire, and is used for receiving an initial signal, wherein the initial signal is a millimeter wave or terahertz signal; the conversion unit comprises a probe and a conversion metal groove, a first end of the probe is connected with the microstrip line signal line, a second end of the probe is connected with the first end of the conversion metal groove, a second end of the conversion metal groove is connected with the waveguide unit, and the conversion unit is used for receiving an initial signal and converting the initial signal into a target signal; the waveguide unit is used for being connected with external equipment, and the waveguide unit receives the target signal transmitted by the conversion unit and transmits the target signal to the external equipment. The conversion device is easy to process, small in size and capable of realizing signal conversion with small bandwidth, small loss and high performance.

Description

Microstrip line-to-waveguide conversion module and microstrip line-to-waveguide broadband conversion method

Technical Field

The present disclosure relates to the field of millimeter wave transmission technologies, and in particular, to a microstrip line-to-waveguide conversion module and a microstrip line-to-waveguide broadband conversion method.

Background

Microstrip lines are very important transmission lines in millimeter-wave terahertz circuits, and are easy to process and connect with various microwave devices. However, when the frequency of the transmission signal is high, the loss of the microstrip line is large, so that transmission is generally performed through a waveguide between integrated systems or with a millimeter wave terahertz test instrument. Therefore, a switching device is required to be provided between the microstrip line and the waveguide to realize signal transmission between the microstrip line and the waveguide.

At present, a conversion device such as stepped ridge waveguide conversion, ridge fin line conversion, coupling probe conversion and the like is arranged between a microstrip line and a waveguide, but the conversion device has the advantages of larger size, narrow bandwidth and poor performance.

Disclosure of Invention

Based on this, it is necessary to provide a microstrip line-to-waveguide conversion module and a microstrip line-to-waveguide broadband conversion method that are small in size, wide in bandwidth, and high in performance.

In a first aspect, the present application provides a microstrip to waveguide conversion module, including a microstrip unit, a conversion unit, and a waveguide unit, the conversion unit is connected with the microstrip unit and the waveguide unit, respectively, wherein:

the microstrip line unit comprises a microstrip line signal line and a microstrip line ground wire, and is used for receiving an initial signal, wherein the initial signal is a millimeter wave or terahertz signal;

the conversion unit comprises a probe and a conversion metal groove, wherein the first end of the probe is connected with the microstrip line signal line, the second end of the probe is connected with the first end of the conversion metal groove, the second end of the conversion metal groove is used for being connected with the waveguide unit, and the conversion unit is used for receiving an initial signal and converting the initial signal into a target signal;

and the waveguide unit is used for being connected with external equipment, receiving the target signal transmitted by the conversion unit and transmitting the target signal to the external equipment.

In one embodiment, a microstrip line signal line is disposed on a first metal layer, a microstrip line ground line is disposed on a second metal layer, a substrate is disposed between the first metal layer and the second metal layer, and the first metal layer, the second metal layer and the substrate are connected through vias corresponding to each layer, wherein:

the conversion metal groove is formed on the second metal layer by forming a metal groove bypassing the via hole, the conversion metal groove comprises a plurality of sections of mutually communicated rectangular grooves, and the first end of the conversion metal groove is closely adjacent to the ground wire of the microstrip line and is in short circuit; the second end of the transition metal slot is adapted to be connected to the waveguide unit.

In one embodiment, the width of each rectangular slot in the first direction is related to the impedance.

In one embodiment, the transition metal slot includes at least three rectangular slots.

In one embodiment, the probe is disposed on the first metal layer by etching, a first end of the probe is connected with the microstrip line signal line, a second end of the probe includes a metal disc, the metal disc is provided with a first via hole, and a center of the metal disc coincides with a center of the first via hole.

In one embodiment, the length of the probe is related to the center frequency wavelength of the target signal.

In one embodiment, the waveguide unit comprises a rectangular heightened waveguide and a rectangular waveguide, wherein a first end of the rectangular heightened waveguide is used for being connected with the conversion unit, and a second end of the rectangular heightened waveguide is connected with the rectangular waveguide; the rectangular height-reducing waveguide and the rectangular waveguide are arranged on the same central line, the heights of the rectangular height-reducing waveguide and the rectangular waveguide are the same, and the width of the rectangular height-reducing waveguide is smaller than that of the rectangular waveguide.

In one embodiment, the end of the rectangular waveguide remote from the rectangular waveguide is short-circuited to form a short-circuited surface, and a channel is formed in the short-circuited surface, the channel being used for inserting the conversion unit into the waveguide unit through the channel.

In one embodiment, the module further comprises a shielding unit disposed above the microstrip line unit for shielding signal radiation of the microstrip line unit.

In a second aspect, the present application provides a microstrip line-to-waveguide broadband conversion method, which is based on the microstrip line-to-waveguide conversion module provided in the first aspect, where the conversion module includes a microstrip line unit, a conversion unit, and a waveguide unit, and the conversion unit is connected to the microstrip line unit and the waveguide unit, respectively, and the method includes:

the microstrip line unit receives an initial signal, wherein the initial signal is a millimeter wave or terahertz signal;

the conversion unit receives an initial signal and converts the initial signal into a target signal;

the waveguide unit receives the target signal of the conversion module unit and transmits the target signal to an external device.

In the microstrip line-to-waveguide conversion module and the microstrip line-to-waveguide broadband conversion method, the microstrip line-to-waveguide conversion module comprises a microstrip line unit, a conversion unit and a waveguide unit, wherein the conversion unit is respectively connected with the microstrip line unit and the waveguide unit, and the microstrip line-to-waveguide broadband conversion method comprises the steps of: the microstrip line unit comprises a microstrip line signal line and a microstrip line ground wire, and is used for receiving an initial signal, wherein the initial signal is a millimeter wave or terahertz signal; the conversion unit comprises a probe and a conversion metal groove, a first end of the probe is connected with the microstrip line signal line, a second end of the probe is connected with the first end of the conversion metal groove, a second end of the conversion metal groove is connected with the waveguide unit, and the conversion unit is used for receiving an initial signal and converting the initial signal into a target signal; the waveguide unit is used for being connected with external equipment, and the waveguide unit receives the target signal transmitted by the conversion unit and transmits the target signal to the external equipment. The conversion module of microstrip line to waveguide of this application sets up conversion metal groove and converts initial signal into the target signal at the conversion unit, compare in the signal conversion of traditional coupling form, the conversion equipment of this application makes the electric field of directional both sides on the microstrip line unit become the electric field of directional unilateral, realize the conversion of electromagnetic field mode, the conversion equipment of this application is easily processed, the size is less, under the verification of limited number of experiments, the conversion equipment that this application provided can realize wide bandwidth signal transmission, signal conversion transmission's loss is little, have better performance.

Drawings

In order to more clearly illustrate the technical solutions of embodiments or conventional techniques of the present application, the drawings required for the descriptions of the embodiments or conventional techniques will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person of ordinary skill in the art.

Fig. 1 is a schematic structural diagram of a microstrip to waveguide conversion module according to an embodiment;

FIG. 2 is a schematic layer diagram of a microstrip line unit in an embodiment;

FIG. 3 is a schematic diagram of a second metal layer according to an embodiment;

FIG. 4 is a schematic diagram of a first metal layer according to an embodiment;

FIG. 5 is a schematic diagram of a waveguide unit according to an embodiment;

fig. 6 is a schematic structural diagram of a microstrip to waveguide conversion module according to an embodiment;

FIG. 7 is a diagram showing electric field distribution vectors of a microstrip to waveguide conversion module according to an embodiment;

fig. 8 is an S-parameter diagram in an embodiment.

Reference numerals illustrate:

100. a microstrip line unit; 110. a microstrip line signal line; 112. a first metal layer; 114. a substrate; 120. a microstrip line ground line; 122. a second metal layer; 200. a conversion unit; 210. a probe; 212. a first via; 220. a transition metal groove; 2202. a first rectangular groove; 2204. a second rectangular groove; 2206. a third rectangular groove; 2208. a fourth rectangular groove; 222. a second via; 300. a waveguide unit; 310. a rectangular height-reducing waveguide; 312. a channel; 320. a rectangular waveguide; 400. and a shielding unit.

Detailed Description

In order to facilitate an understanding of the present application, a more complete description of the present application will now be provided with reference to the relevant figures. Examples of the present application are given in the accompanying drawings. This application may, however, be embodied in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein in the description of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

It will be understood that the terms "first," "second," and the like, as used herein, may be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish one element from another element. For example, a first metal layer may be referred to as a second metal layer, and similarly, a second metal layer may be referred to as a first metal layer, without departing from the scope of the present application. Both the first metal layer and the second metal layer are resistive, but they are not the same metal layer.

It is to be understood that in the following embodiments, "connected" is understood to mean "electrically connected", "communicatively connected", etc., if the connected circuits, modules, units, etc., have electrical or data transfer between them.

It is understood that "at least one" means one or more and "a plurality" means two or more. "at least part of an element" means part or all of the element.

As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," and/or the like, specify the presence of stated features, integers, steps, operations, elements, components, or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof. Also, the term "and/or" as used in this specification includes any and all combinations of the associated listed items.

As shown in fig. 1, in one embodiment, a microstrip-to-waveguide conversion module is provided, which includes a microstrip unit 100, a conversion unit 200, and a waveguide unit 300, the conversion unit 200 being connected to the microstrip unit 100 and the waveguide unit 300, respectively; the microstrip line unit 100 includes a microstrip line signal line 110 and a microstrip line ground line 120, and the microstrip line unit 100 is configured to receive an initial signal, where the initial signal is a millimeter wave or terahertz signal; the conversion unit 200 includes a probe 210 and a conversion metal groove 220, a first end of the probe 210 is connected with the microstrip line signal line 110, a second end of the probe 210 is connected with a first end of the conversion metal groove 220, a second end of the conversion metal groove 220 is connected with the waveguide unit 300, and the conversion unit 200 is used for receiving an initial signal and converting the initial signal into a target signal; the waveguide unit 300 is used for connection with an external device, and the waveguide unit 300 receives the target signal transmitted by the conversion unit 200 and transmits the target signal to the external device.

The microstrip line unit 100 includes a microstrip line signal line 110 and a microstrip line ground line 120, and is configured to receive an initial signal, where the microstrip line unit 100 may be connected to various microwave devices to receive the initial signal, where the initial signal may be a signal with a higher frequency such as millimeter wave or terahertz, and because the frequency of such a signal is higher and needs to be transmitted through the waveguide unit 300, in the middle of the microstrip line unit 100 and the waveguide unit 300, a conversion unit 200 is formed by setting a conversion metal slot 220, where the setting of the conversion metal slot 220 may enable an electric field pointing to two sides on the microstrip line signal line 110 to be changed into an electric field pointing to a single side, so as to implement conversion of an electromagnetic field mode.

In one embodiment, as shown in fig. 2, the microstrip signal line 110 is disposed on the first metal layer 112, the microstrip ground line 120 is disposed on the second metal layer 122, the substrate 114 is disposed between the first metal layer 112 and the second metal layer 122, and the first metal layer 112, the second metal layer 122 and the substrate 114 are connected through corresponding vias of each layer, where: the conversion metal groove 220 is formed on the second metal layer 122 by forming a metal groove bypassing the second via hole 222, the conversion metal groove 220 comprises a plurality of sections of rectangular grooves which are mutually communicated, and the first end of the conversion metal groove 220 is closely adjacent to the microstrip line ground line 120 and is short-circuited; a second end of the transition metal slot 220 is used to connect with the waveguide unit 300.

Wherein, the first metal layer 112 and the second metal layer 122 are processed by single-layer printed circuit board process, the via holes are holes for electrical connection between the PCB boards, and the via holes connect the substrate 114, the first metal layer 112 and the second metal layer 122 together, which can be understood as connecting wires between the substrate 114, the first metal layer 112 and the second metal layer 122, specifically, the via holes are formed on the substrate 114, the first metal layer 112 and the second metal layer 122, and the layers are connected through the via holes. The via hole in this embodiment is a metallized via hole, i.e. the side wall of the via hole is metallized, so as to realize the connection of each layer.

The microstrip line signal line 110 is formed on the first metal layer 112 by etching, the first metal layer 112 is disposed above the substrate 114, a second metal layer 122 is disposed below the substrate 114, the second metal layer 122 is provided with a microstrip line ground line 120 corresponding to the microstrip line signal line 110, and the first metal layer 112 and the second metal layer 122 of the substrate 114 are connected by vias corresponding to the respective layers.

As shown in fig. 3, a transition metal groove 220 is provided on the second metal layer 122 in addition to the microstrip line ground line 120, the transition metal groove 220 being for effecting transition between the initial signal and the target signal so that the target signal can be connected to an external device through the waveguide unit 300. The transition metal groove 220 is formed by forming a metal groove around the second via hole 222 on the second metal layer 122, as shown in fig. 3, the transition metal groove 220 includes a plurality of rectangular grooves which are mutually communicated, a first end of the transition metal groove 220 is adjacent to the microstrip line ground line 120 but has no connection relationship, a first end of the transition metal groove 220 is disposed in a short circuit, and a second end is used for being connected with the waveguide unit 300.

Compared with the conventional coupling mode for signal conversion, the conversion module of the present embodiment is realized by providing a metal layer, which is easy to process and has a smaller size, and the conversion metal slot 220 changes the electric field pointing to two sides on the microstrip line into the electric field pointing to a single side, so that the conversion of the electromagnetic field mode can be realized. In addition, direct communication is generally inconvenient between the microstrip line unit 100 and the waveguide unit 300, so that the inlet direction of the conventional waveguide unit 300 is parallel to the microstrip line signal line 110 in the microstrip line unit 100 or a non-axial conversion structure is used, which is not beneficial to layout and increases loss in the signal conversion and transmission process. The conversion metal slot 220 provided in this embodiment can realize axial transmission conversion between the microstrip line unit 100 and the waveguide unit 300, and experiments prove that the conversion module of this embodiment has the advantages of small return loss and low transmission loss.

Illustratively, the transition metal trench 220 in fig. 3 includes four interconnected rectangular trenches, namely a first rectangular trench 2202, a second rectangular trench 2204, a third rectangular trench 2206, and a fourth rectangular trench 2208 in the figure, wherein the four rectangular metal trenches are disposed around the second via 222 formed in the second metal layer 122, and the four matrix metal trenches are interconnected. As shown in fig. 3, the first rectangular groove 2202 is adjacent to the microstrip line ground line 120 but the first rectangular groove 2202 is not connected to the microstrip line ground line 120, the first rectangular groove 2202 is short-circuited to the adjacent end of the microstrip line ground line 120, and the end of the fourth rectangular groove 2208 is used for connection to the waveguide unit 300.

It should be noted that, the above-mentioned conversion metal groove 220 may also take other forms, not limited to the forms already mentioned in the above-mentioned embodiments, and the number of rectangular metal grooves included in the conversion metal groove 220 is not limited, and three rectangular metal grooves may be provided, or six rectangular metal grooves may be provided, so long as it can achieve the function of completing conversion transmission of signals.

Compared with the traditional signal transmission conversion device, the conversion module of the embodiment is obtained by arranging the rectangular metal groove on the metal layer connected with the microstrip line, has a compact structure and is easy to process, and the whole size of the conversion module is small.

In one embodiment, the width of each rectangular slot in the first direction is related to the impedance.

The characteristic impedance of the general-purpose materials in the fields of microwave radio frequency circuits, microwave passive devices, antennas and the like is usually 50Ω, and in the fields of microwave circuits, microwave antenna systems, the impedance value may be large, for example, may exceed 300Ω. Since the conversion unit 200 is required to perform signal transmission and conversion between the microstrip line unit 100 and the waveguide unit 300, the width of each rectangular slot in the conversion metal slot 220 is required to be matched with the impedance, that is, the width of each rectangular slot in the conversion metal slot 220 is set according to the difference of the impedance.

The first direction is a direction perpendicular to the signal transmission direction, and the direction of arrow a in fig. 3 indicates the first direction. Taking the conversion unit 200 shown in fig. 3 as an example, the conversion unit 200 is configured to implement axial conversion of signals, so that four mutually connected rectangular slots are configured to avoid the second via hole 222. The widths of the rectangular grooves in the conversion metal groove 220 are different, and as shown in fig. 3, the widths of the second rectangular groove 2204 and the fourth rectangular groove 2208 in the first direction are the same, and the widths of the first rectangular groove 2202 and the third rectangular groove 2206 are smaller than the widths of the second rectangular groove 2204 and the fourth rectangular groove 2208. How to determine the width of the rectangular slot through impedance specifically has a detailed calculation formula in the electromagnetic wave theory, and will not be described here again.

It should be noted that the conversion metal groove 220 may be other forms, and fig. 3 is only an example. The conversion metal groove 220 in this embodiment is formed by grooving on the second metal layer 122, so that conversion of electromagnetic wave modes can be achieved, and experiments prove that the conversion module in this embodiment has good impedance matching, has a relatively wide bandwidth and relatively small loss, and can achieve full coverage of the Y-band in wireless communication.

In one embodiment, transition metal slot 220 includes at least three rectangular slots.

The conversion metal grooves 220 include a plurality of segments of rectangular grooves communicating with each other, and the design of each rectangular groove is realized based on the angle of mode conversion and impedance matching of signals, and thus, the width of each rectangular groove is related to impedance. In order to implement the transition between the microstrip line unit 100 and the waveguide unit 300 and avoid the second via 222 on the second metal layer 122, the transition metal groove 220 needs to include at least three rectangular grooves.

In one embodiment, as shown in fig. 4, the probe 210 is disposed on the first metal layer 112 by etching, and a first end of the probe 210 is connected to the microstrip line signal line 110, and a second end of the probe 210 includes a metal disc, where the metal disc is provided with a first via 212, and a center of the metal disc coincides with a center of the first via 212.

The first metal layer 112 is connected to the substrate 114 and the second metal layer 122 through the first via 212, and the microstrip line signal line 110 and the probe 210 are formed on the first metal layer 112 by etching, as shown in fig. 2 and fig. 4, the microstrip line signal line 110 is in a metal strip shape, the microstrip line signal line 110 is connected to the probe 210, the second end of the probe 210 includes a metal disc, the metal disc is provided with the first via 212, and for convenience in setting and efficient transmission of signals, the center of the metal disc coincides with the center of the first via 212.

In one embodiment, the length of the probe 210 is related to the center frequency wavelength of the target signal.

For example, in order to maximize the coupling efficiency of the probe 210, the length of the probe 210 is determined according to the center frequency wavelength of the target signal. Assuming that the center frequency wavelength of the operating bandwidth of the target signal is λ, the position at a 1/4 wavelength distance from the short-circuit surface of the waveguide unit 300 is the antinode position where the electric field is strongest, and thus the length of the probe 210 may be set to 1/4λ to obtain better coupling efficiency.

In one embodiment, as shown in fig. 5, the waveguide unit 300 includes a rectangular elevation-reducing waveguide 310 and a rectangular waveguide 320, a first end of the rectangular elevation-reducing waveguide 310 is used to connect with the conversion unit 200, and a second end of the rectangular elevation-reducing waveguide 310 is connected with the rectangular waveguide 320; the rectangular height-reducing waveguide 310 and the rectangular waveguide 320 are on the same central line, the heights of the rectangular height-reducing waveguide 310 and the rectangular waveguide 320 are the same, and the width of the rectangular height-reducing waveguide 310 is smaller than that of the rectangular waveguide 320.

Wherein, one end of the rectangular waveguide 320, which is far away from the rectangular elevation-reducing waveguide 310, is used for connecting with an external signal port for transmitting the converted signal to an external device. The rectangular height-reducing waveguide 310 and the rectangular waveguide 320 are both rectangular metal grooves in a metal block, and the rectangular height-reducing waveguide 310 has a smaller width than the rectangular waveguide 320 for suppressing the higher order modes. When the microstrip signal line 110 is too wide, higher order modes may occur, and the higher order modes may affect the performance of the microstrip transmission line or waveguide in some cases, such as attenuation, increased transmission loss, and inter-mode crosstalk. Therefore, in designing and using waveguides, high order modes need to be analyzed and considered sufficiently to ensure the desired transmission characteristics and performance. When the conversion module of the embodiment realizes the transmission conversion between the microstrip line unit 100 and the waveguide unit 300, the rectangular height-reducing waveguide 310 is arranged between the microstrip line signal line 110 and the rectangular waveguide 320, and the width of the waveguide is reduced to inhibit the higher order mode by optimizing the waveguide size, so that the transmission performance is improved.

In one embodiment, as shown in the schematic structure of the waveguide unit 300 in fig. 5, one end of the rectangular elevation-reducing waveguide 310, which is far from the rectangular waveguide 320, is short-circuited to form a short-circuited surface, and a channel 312 is formed in the short-circuited surface, and the channel 312 is used for inserting the conversion unit 200 into the waveguide unit 300 through the channel 312.

Wherein the channel 312 is formed by boring a hole on the short road surface, and the probe 210 in the conversion unit 200 and the corresponding conversion metal groove 220 are inserted into the rectangular elevation-reducing waveguide 310 of the waveguide unit 300 through the channel 312.

In one embodiment, the module further comprises a shielding unit 400, the shielding unit 400 being arranged above the microstrip line unit 100 for shielding signal radiation of the microstrip line unit 100.

Illustratively, the shielding unit 400 is a rectangular metal groove, the upper side of the shielding unit 400 is flush with the waveguide unit 300, the lower side of the shielding unit 400 is flush with the microstrip line ground line 120, and the length of the shielding unit 400 is the same as the microstrip line signal line 110. The shielding unit 400 may shield signal radiation of the microstrip line unit 100, thereby reducing influence of the microstrip line unit 100 on other circuits.

It is understood that the size and dimensions of the shielding unit 400 may take other forms, without being limited to the size limitation of the above example, as long as the shielding unit 400 can perform the function of radiation shielding the microstrip-line signal line 110 in the microstrip-line unit 100.

In one embodiment, the microstrip line to waveguide conversion module shown in fig. 6 is a schematic structural diagram, and includes: the microstrip line unit 100, the conversion unit 200, the waveguide unit 300 and the shielding unit 400, the conversion unit 200 is respectively connected with the microstrip line unit 100 and the waveguide unit 300, the conversion unit 200 is used for realizing signal conversion transition between the microstrip line and the waveguide between the waveguide unit 300 and the microstrip line unit 100, and the shielding unit 400 is arranged above the microstrip line unit 100 and is used for shielding signal radiation of the microstrip line unit 100.

As shown in fig. 6, the microstrip line unit 100 includes a substrate 114, a first metal layer 112 disposed above the substrate 114, and a second metal layer 122 disposed below the substrate 114, and the substrate 114, the first metal layer 112, and the second metal layer 122 are connected according to vias.

The first metal layer 112 is processed by a single-layer printed circuit board process, a microstrip line signal line 110 and a probe 210 are formed on the first metal layer 112 by etching, a first end of the probe 210 is connected with the microstrip line signal line 110, a second end of the probe 210 comprises a metal disc, a first via hole 212 is formed on the metal disc, and the first via hole 212 is a metallized via hole.

In one possible implementation, the length of probe 210 is 1/4λ, λ being the center frequency wavelength of the target signal.

The second metal layer 122 is also processed by a single-layer printed circuit board process, and a second via 222 corresponding to the first via 212 is disposed on the second metal layer 122, where the second via 222 is a metallized via for realizing connection among the substrate 114, the first metal layer 112 and the second metal layer 122. The second metal layer 122 is provided with a microstrip line ground line 120 and a conversion metal groove 220, the microstrip line ground line 120 corresponds to the microstrip line signal line 110, and the conversion metal groove 220 is formed by forming a metal groove bypassing the second via hole 222 on the second metal layer 122. In addition, in the case of the optical fiber,

in one possible implementation, the transition metal slot 220 includes four interconnected rectangular slots, namely, a first rectangular slot 2202, a second rectangular slot 2204, a third rectangular slot 2206, and a fourth rectangular slot 2208 in the drawing, where the widths of all the rectangular slots in the transition metal slot 220 in the first direction match the impedance, and the first rectangular slot 2202 is adjacent to the microstrip line ground line 120 but the first rectangular slot 2202 is not connected to the microstrip line ground line 120, and the adjacent ends of the first rectangular slot 2202 and the microstrip line ground line 120 are short-circuited, and the end of the fourth rectangular slot 2208 is used for connection to the waveguide unit 300.

The waveguide unit 300 includes a rectangular elevation-reducing waveguide 310 and a rectangular waveguide 320, a first end of the rectangular elevation-reducing waveguide 310 being used to be connected with the conversion unit 200, and a second end of the rectangular elevation-reducing waveguide 310 being connected with the rectangular waveguide 320; the rectangular height-reducing waveguide 310 and the rectangular waveguide 320 are on the same central line, the heights of the rectangular height-reducing waveguide 310 and the rectangular waveguide 320 are the same, and the width of the rectangular height-reducing waveguide 310 is smaller than that of the rectangular waveguide 320.

In the waveguide unit 300, one end of the rectangular elevation-reducing waveguide 310, which is far from the rectangular waveguide 320, is short-circuited to form a short-circuited surface, and a channel 312 is opened at the short-circuited surface, and the channel 312 is used for the switching unit 200 to be inserted into the waveguide unit 300 through the channel 312.

The axial unbalanced short-circuit probe is adopted for conversion transition, so that the axial transmission conversion between the microstrip line unit 100 and the waveguide unit 300 is realized, and the advantages of low return loss and low transmission loss are achieved. Compared with the traditional signal transmission conversion device, the conversion module of the embodiment is obtained by arranging the rectangular metal groove on the metal layer connected with the microstrip line, has compact structure and small size, and is easy to process.

Fig. 7 is a diagram showing an electric field distribution vector of a microstrip line-to-waveguide conversion module according to this embodiment, where according to fig. 7, a transmission mode of an electromagnetic field is changed by a microstrip line-to-waveguide conversion device according to this embodiment, and by using a microstrip line-to-waveguide conversion device according to this embodiment, an electric field on both sides of the microstrip line is changed to be directed to a single side, thereby realizing conversion of an electromagnetic field mode.

Fig. 8 is an S-parameter diagram (Scattering Parameters Chart) that may be used to describe the frequency response and transmission performance of a microwave circuit, by which the transmission characteristics of the device may be quantitatively described, in one embodiment. In fig. 8, a curve S11 shows return loss, and a curve S21 shows insertion loss, and the microstrip line-to-waveguide conversion module of the present embodiment is obtained through experiments, where the bandwidth of-15 dB is 165.71-273.75GHz (relative bandwidth is 49%), the entire Y band is covered, the insertion loss is less than 0.68dB in the operating band, and the microstrip line-to-waveguide conversion module has the advantages of low return loss and low transmission loss, and is a high-performance microstrip line-to-waveguide conversion module.

In one embodiment, a method for converting a microstrip line into a waveguide is disclosed, where the method includes, by using the microstrip line-to-waveguide conversion device provided in the foregoing embodiments, implementing signal conversion transition between the microstrip line and the waveguide, where the method includes:

the microstrip line unit 100 receives an initial signal, wherein the initial signal is a millimeter wave or terahertz signal;

the conversion unit 200 receives an initial signal and converts the initial signal into a target signal;

the waveguide unit 300 receives the target signal of the conversion module unit and transmits the target signal to an external device.

The microstrip line-to-waveguide conversion module described above may also be applied to a millimeter wave terahertz circuit or related devices for realizing signal conversion between the microstrip line unit 100 and the waveguide unit 300.

In the description of the present specification, reference to the term "some embodiments," "other embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic descriptions of the above terms do not necessarily refer to the same embodiment or example.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples only represent a few embodiments of the present application, which are described in more detail and are not to be construed as limiting the scope of the present application. It should be noted that it would be apparent to those skilled in the art that various modifications and improvements could be made without departing from the spirit of the present application, which would be within the scope of the present application. Accordingly, the scope of protection of the present application shall be subject to the appended claims.

Claims (10)

1. The microstrip line to waveguide conversion module is characterized by comprising a microstrip line unit, a conversion unit and a waveguide unit, wherein the conversion unit is respectively connected with the microstrip line unit and the waveguide unit, and the microstrip line to waveguide conversion module comprises:

the microstrip line unit comprises a microstrip line signal line and a microstrip line ground wire, and is used for receiving an initial signal, wherein the initial signal is a millimeter wave or terahertz signal;

the conversion unit comprises a probe and a conversion metal groove, wherein a first end of the probe is connected with the microstrip line signal line, a second end of the probe is connected with the first end of the conversion metal groove, a second end of the conversion metal groove is used for being connected with the waveguide unit, and the conversion unit is used for receiving the initial signal and converting the initial signal into a target signal;

the waveguide unit is used for being connected with external equipment, and the waveguide unit receives the target signal transmitted by the conversion unit and transmits the target signal to the external equipment.

2. The module of claim 1, wherein the microstrip signal line is disposed on a first metal layer, the microstrip ground line is disposed on a second metal layer, a substrate is disposed between the first metal layer and the second metal layer, and the first metal layer, the second metal layer and the substrate are connected by corresponding vias of each layer, wherein:

the conversion metal groove is formed on the second metal layer by forming a metal groove which bypasses the via hole, the conversion metal groove comprises a plurality of sections of mutually communicated rectangular grooves, and the first end of the conversion metal groove is closely adjacent to the microstrip line ground wire and is short-circuited; the second end of the transition metal groove is used for being connected with the waveguide unit.

3. The module of claim 2, wherein a width of each of the rectangular grooves in the first direction is related to the impedance.

4. The module of claim 2, wherein the transition metal slot comprises at least three rectangular slots.

5. The module of claim 1, wherein the probe is disposed on the first metal layer by etching, a first end of the probe is connected to the microstrip line signal line, a second end of the probe comprises a metal disc, the metal disc is provided with a first via, and a center of the metal disc coincides with a center of the first via.

6. The module of claim 5, wherein the length of the probe is related to a center frequency wavelength of the target signal.

7. The module of claim 1, wherein the waveguide unit comprises a rectangular-shaped height-reducing waveguide and a rectangular-shaped waveguide, a first end of the rectangular-shaped height-reducing waveguide being for connection with the conversion unit, a second end of the rectangular-shaped height-reducing waveguide being connected with the rectangular-shaped waveguide; the rectangular height-reducing waveguide and the rectangular waveguide are arranged on the same central line, the heights of the rectangular height-reducing waveguide and the rectangular waveguide are the same, and the width of the rectangular height-reducing waveguide is smaller than that of the rectangular waveguide.

8. The module according to claim 7, wherein an end of the rectangular waveguide facing away from the rectangular waveguide is short-circuited to form a short-circuited surface, and a channel is provided in the short-circuited surface, the channel being for the switching unit to be inserted into the waveguide unit through the channel.

9. The module according to claim 1, further comprising a shielding unit disposed above the microstrip line unit for shielding signal radiation of the microstrip line unit.

10. A microstrip line to waveguide broadband conversion method, characterized in that based on a microstrip line to waveguide conversion module according to any one of claims 1-9, said conversion module comprises a microstrip line unit, a conversion unit and a waveguide unit, said conversion unit being connected to said microstrip line unit and said waveguide unit, respectively, said method comprising:

the microstrip line unit receives an initial signal, wherein the initial signal is a millimeter wave or terahertz signal;

the conversion unit receives the initial signal and converts the initial signal into a target signal;

the waveguide unit receives the target signal of the conversion module unit and transmits the target signal to an external device.