CN220652315U - Waveguide microstrip conversion structure - Google Patents

Abstract

The utility model discloses a waveguide microstrip conversion structure, which comprises: a base, a probe, and a shorting block; the base is provided with a bearing surface, and a first boss and a second boss are sequentially formed on the bearing surface from low to high; the utility model has the advantages that the structure is simple, the production difficulty is low, and the assembly is convenient.

Description

Waveguide microstrip conversion structure

Technical Field

The utility model belongs to the technical field of microwave communication, and particularly relates to a waveguide microstrip conversion structure.

Background

In recent years, industries such as 5G communication, vehicle millimeter wave radar and the like develop rapidly, and millimeter wave systems are increasingly widely used. The use of monolithic integrated circuits (MMICs) in millimeter wave systems often requires a transition from a waveguide interface to a microstrip interface. Currently, three transition modes are generally used: step ridge waveguide transition, ridge-to-fin line transition, coupling probe transition. The step ridge waveguide has complex transition processing and high precision requirement; a series of resonant modes are required for the ridge-fin line transition, and if the resonant frequency is in the working bandwidth, the device coupling performance can be affected; the coupling probe has the advantages of simple transition structure, convenient processing, easy assembly and most extensive use.

The coupling probe transition structure is mainly divided into 2 types of coaxial probe type and microstrip probe type. Wherein the coaxial probe type structure is commonly used for system circuits below Ka wave band (40 GHz); for the system circuit above the V-band (50 GHz), the high-performance coaxial probe structure has high requirements, difficult processing and high cost, so a microstrip probe type waveguide microstrip transition structure is generally adopted, but the traditional waveguide microstrip transition structure has large volume, complex structure and low assembly efficiency at present, and in order to solve the problems, a waveguide microstrip transition structure is proposed.

Disclosure of Invention

The present utility model aims to solve at least one of the technical problems existing in the prior art.

Therefore, the utility model provides the waveguide microstrip conversion structure which has the advantages of simple structure, low production difficulty and convenient assembly.

According to an embodiment of the present utility model, a waveguide microstrip transition structure includes: a base, a probe, and a shorting block; the base is in a ladder shape and is provided with a bearing surface, and a first boss and a second boss are sequentially formed on the bearing surface from low to high; the base is provided with a waveguide port penetrating through the lower surface of the base and the upper surface of the first boss in the height direction, one side of the upper end of the waveguide port is provided with an opening, the opening is communicated with a bearing surface, one end of a probe is placed on the bearing surface, the other end of the probe penetrates through the opening and stretches into the waveguide port, the probe is perpendicular to the opening direction of the waveguide port, one side of the lower surface of the short-circuit block is provided with a third boss, the lower surface of the short-circuit block is placed on the first boss, the lower surface of the third boss is close to the bearing surface, and the lower surface of the third boss is provided with a probe hole in the width direction for passing through the probe on the bearing surface, and the short-circuit block is connected with the base.

According to one embodiment of the utility model, the bearing surface is horizontally arranged, the side surface of the first boss is a reference surface, the reference surface is perpendicular to the bearing surface, the upper surface of the first boss is a first positioning surface, the side surface of the second boss is a second positioning surface, the second positioning surface is perpendicular to the first positioning surface, and the first positioning surface is parallel to the bearing surface.

According to one embodiment of the utility model, the width of the first boss is the same as the width of the shorting block.

According to one embodiment of the present utility model, a side wall of the third boss is on the same plane as a side wall of the short circuit block, and when the short circuit block is placed on the first boss, the side wall of the short circuit block is on the same plane as the reference plane.

According to one embodiment of the utility model, when the short circuit block is placed on the first boss, the other side wall of the short circuit block is attached to the second positioning surface.

According to one embodiment of the utility model, the width of the third boss is the same as the width of the opening.

According to one embodiment of the utility model, the base is connected with the short-circuit block by two bolts, and the two bolts are respectively positioned at two sides of the waveguide port.

According to one embodiment of the utility model, the waveguide port has a rectangular cross section.

According to one embodiment of the utility model, the probe comprises: the micro-strip circuit comprises a substrate, a micro-strip circuit layer and a grounding metal layer; the substrate is located between the microstrip circuit layer and the grounding metal layer, the microstrip circuit layer is the top layer of the probe, the grounding metal layer is the bottom layer of the probe, and the microstrip circuit layer faces the short-circuit block.

The utility model has the beneficial effects that the stepped base and the short circuit block with the boss are adopted, so that the number of positioning surfaces between the base and the boss is increased, and the base and the boss are clamped more accurately, thereby being convenient for direct assembly.

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

In order to make the above objects, features and advantages of the present utility model more comprehensible, preferred embodiments accompanied with figures are described in detail below.

Drawings

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

FIG. 1 is a schematic view of the overall structure of the present utility model;

FIG. 2 is a schematic diagram illustrating the overall structure of the present utility model in a disassembled form;

FIG. 3 is a schematic side cross-sectional view of the present utility model;

FIG. 4 is a schematic front view of a probe according to the present utility model;

FIG. 5 is a schematic side view of a probe of the present utility model;

FIG. 6 is a schematic top view of the base of the present utility model;

FIG. 7 is a schematic view of a cross-section of the base A of the present utility model;

FIG. 8 is a schematic diagram of a shorting block in front view of the present utility model;

FIG. 9 is a schematic bottom view of a shorting block of the present utility model;

FIG. 10 is a diagram showing simulation results of reflection loss (S11) of the W-band application example of the present utility model;

FIG. 11 is a diagram showing the actual measurement result of the reflection loss (S11) of the W-band application example of the present utility model;

reference numerals:

1. a base; 11. a bearing surface; 12. a first boss; 121. a first positioning surface; 122. a reference surface; 13. a second boss; 131. a second positioning surface; 14. a waveguide port; 2. a probe; 21. a substrate; 22. a microstrip circuit layer; 23. a grounded metal layer; 3. a shorting block; 31. a third boss; 311. a probe hole.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative only and are not to be construed as limiting the utility model.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present utility model. Furthermore, features defining "first", "second" may include one or more such features, either explicitly or implicitly. In the description of the present utility model, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present utility model, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

The waveguide microstrip transition structure of the embodiment of the present utility model is specifically described below with reference to the accompanying drawings.

As shown in fig. 1 to 11, a waveguide microstrip transition structure according to an embodiment of the present utility model includes: a base 1, a probe 2 and a short circuit block 3; the base 1 is in a ladder shape, the base 1 is provided with a bearing surface 11, and a first boss 12 and a second boss 13 are sequentially formed on the bearing surface 11 from low to high; the base 1 is provided with a waveguide port 14 penetrating through the lower surface of the base 1 and the upper surface of the first boss 12 along the height direction, one side of the upper end of the waveguide port 14 is provided with an opening, the opening is communicated with the bearing surface 11, one end of the probe 2 is placed on the bearing surface 11, the other end of the probe 2 penetrates through the opening and stretches into the waveguide port 14, the probe 2 is perpendicular to the opening direction of the waveguide port 14, one side of the lower surface of the short circuit block 3 is provided with a third boss 31, the lower surface of the short circuit block 3 is placed on the first boss 12, the lower surface of the third boss 31 is close to the bearing surface 11, a probe hole 311 is formed in the lower surface of the third boss 31 along the width direction so as to be used for connecting the short circuit block 3 with the base 1 through the probe 2 on the bearing surface 11.

Further, the third boss 31 is located at the center of the opening, sharp edges are reserved at the openings at two ends of the waveguide port 14, the waveguide port 14 is not chamfered or rounded after deburring, the size of the waveguide port 14 is determined according to the required working frequency of the device and relevant standard rules, the probe hole 311 surrounds the probe 2, the probe hole 311 is used for passing through the probe 2 and forming a signal transmission cavity at the top of the probe 2, and the probe 2 is fixed on the supporting surface 11 by adopting conductive adhesive.

The bearing surface 11 is horizontally arranged, the side surface of the first boss 12 is a reference surface 122, the reference surface 122 is vertical to the bearing surface 11, the upper surface of the first boss 12 is a first positioning surface 121, the side surface of the second boss 13 is a second positioning surface 131, the second positioning surface 131 is vertical to the first positioning surface 121, and the first positioning surface 121 is parallel to the bearing surface 11.

The width of the first boss 12 is the same as the width of the shorting block 3.

When the short circuit block 3 is placed on the first boss 12, a side wall of the short circuit block 3 is located on the same plane as the reference surface 122, so that after the short circuit block 3 is installed, whether the short circuit block 3 is installed in place is determined by observing whether a side wall of the short circuit block 3 is located on the same plane as the reference surface 122.

When the short circuit block 3 is placed on the first boss 12, the other side wall of the short circuit block 3 is attached to the second positioning surface 131.

That is, each surface of the third boss 31 and each surface of the short-circuit block 3 are kept well horizontal or vertical to ensure the bonding degree with each bonding surface of the base 1.

The cross section of the waveguide port 14 is rectangular, and the width of the third boss 31 is the same as the width of the opening, that is, when the shorting block 3 is mounted on the base 1, the other side wall of the third boss 31 and one side wall of the waveguide port 14 are located on the same plane, so that the inside of the waveguide port 14 closed by the shorting block 3 is still square.

Two bolts are adopted between the base 1 and the short-circuit block 3 and are respectively and uniformly distributed on two sides of the waveguide port 14 so as to ensure the accuracy of mounting the base 1 and the short-circuit block 3.

The probe 2 includes: a substrate 21, a microstrip circuit layer 22, and a ground metal layer 23; the substrate 21 is located between the microstrip circuit layer 22 and the grounding metal layer 23, the microstrip circuit layer 22 is the top layer of the probe 2, the grounding metal layer 23 is the bottom layer of the probe 2, and the microstrip circuit layer 22 faces the short-circuit block 3.

The substrate 21 is alumina or aluminum nitride, the microstrip circuit layer 22 is a thin metal layer, the shape and the size of which are determined by the related design calculation, the signal transmission function is realized, the grounding metal layer 23 is a thin metal layer, the shape of which is a simple rectangle, the connection and the grounding functions are realized, and the grounding metal layer 23 is not arranged at the part of the probe 2 positioned in the waveguide port 14.

In the first embodiment, the working frequency of the W wave band is 75-110GHz, and the size of the rectangular waveguide port 14 is 2.54 multiplied by 1.27mm according to the standard, so that the size W1 of the waveguide port 14 of the base 1 is 2.54mm, and the size L1 is 1.27mm; according to design calculation, the height difference H1 between the bearing surface 11 and the first positioning surface 121 is 0.94mm, the distance L3 between the reference surface 122 and one side wall of the waveguide port 14 is 1mm, and the distance L2 between the second positioning surface 131 and one side wall of the waveguide port 14 is 2.14mm;

according to design calculation, the dimension W2 of the probe 2 is 0.5mm, L5 is 2mm, and the length L4 of the other end of the probe 2 extending into the waveguide port 14 is 0.6mm;

depending on the dimensions of the base 1, the dimensions h4=h1=0.94 mm, l6=l3=1 mm, l7=l2=2.14 mm of the shorting block 3, W4 can be designed to be 2.5mm, taking into account the assembly requirements; w3 may be designed to be 0.55mm depending on the size of probe 2 and considering assembly requirements; through design calculation, the probe hole 311 has a height h3=0.3 mm.

In summary, the waveguide microstrip conversion structure has low manufacturing cost: the dimensional tolerance is reasonably designed, the minimum tolerance zone of the machining part is 0.04mm, the production can be completed by conventional precise machining, the minimum tolerance zone of the thin film circuit (probe 2) part is 4um, the production can be completed by a precise deposition process, other structures do not exist in the waveguide port 14 of the base 1, the depth of the waveguide port 14 can be flexibly adjusted according to the thickness of the bottom layer of the base 1, and the production difficulty is reduced;

the assembly efficiency is high: the number of parts is small, the assembly steps are few, the structure is simple and visual, a plurality of mutually-attached positioning surfaces are arranged between the base 1 and the short-circuit block 3, the effect of accurate positioning during assembly is realized, a special tool is not needed, an operator can quickly get on hand, and the device is suitable for large-scale and small-scale production;

the application range is wide: the waveguide microstrip conversion structure is verified to be suitable for 50-110GHz (V, E, W wave band) waveguide microstrip conversion, and only the related structure size is required to be modified for different frequency bands without redesigning;

the performance effect is good: the simulation results of the reflection loss (S11) of the waveguide microstrip conversion structure are all better than-20 dB in the frequency range of 50-110GHz, and the actual results in the tolerance allowable range are all better than-15 dB.

The height difference between the supporting surface 11 and the first positioning surface 121, the size of the microstrip circuit layer 22, and the size of the probe hole 311 can be customized as required.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," 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 utility model. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

While embodiments of the present utility model have been shown and described, it will be understood by those of ordinary skill in the art that: many changes, modifications, substitutions and variations may be made to the embodiments without departing from the spirit and principles of the utility model, the scope of which is defined by the claims and their equivalents.

Claims (9)

1. A waveguide microstrip transition structure, comprising:

the base (1) is in a ladder shape, the base (1) is provided with a bearing surface (11), and a first boss (12) and a second boss (13) are sequentially formed on the bearing surface (11) from low to high; the base (1) is provided with a waveguide port (14) penetrating through the lower surface of the base (1) and the upper surface of the first boss (12) along the height direction, one side of the upper end of the waveguide port (14) is provided with an opening, and the opening is communicated with the bearing surface (11);

one end of the probe (2) is placed on the bearing surface (11), the other end of the probe (2) penetrates through the opening and stretches into the waveguide port (14), and the probe (2) is perpendicular to the opening direction of the waveguide port (14);

the short circuit piece (3), one side of short circuit piece (3) lower surface is formed with third boss (31), the lower surface of short circuit piece (3) is placed on first boss (12), the lower surface of third boss (31) is close to bearing face (11), probe hole (311) are opened along width direction to third boss (31) lower surface to be used for through probe (2) on bearing face (11), short circuit piece (3) are connected with base (1).

2. The waveguide microstrip transition structure according to claim 1, wherein the supporting surface (11) is horizontally disposed, a side surface of the first boss (12) is a reference surface (122), the reference surface (122) is perpendicular to the supporting surface (11), an upper surface of the first boss (12) is a first positioning surface (121), a side surface of the second boss (13) is a second positioning surface (131), the second positioning surface (131) is perpendicular to the first positioning surface (121), and the first positioning surface (121) is parallel to the supporting surface (11).

3. Waveguide microstrip transition structure according to claim 2, characterized in that the width of said first boss (12) is the same as the width of the shorting block (3).

4. A waveguide microstrip transition structure according to claim 3, wherein a side wall of said third boss (31) is on the same plane as a side wall of said shorting block (3), and a side wall of said shorting block (3) is on the same plane as said reference plane (122) when said shorting block (3) is placed on said first boss (12).

5. The waveguide microstrip transition structure according to claim 4, wherein when said shorting block (3) is placed on the first boss (12), the other side wall of said shorting block (3) is attached to the second positioning surface (131).

6. The waveguide microstrip transition structure according to claim 5, wherein the width of said third boss (31) is the same as the width of the opening.

7. The waveguide microstrip transition structure according to claim 1, wherein two bolts are connected between said base (1) and said shorting block (3), said two bolts being located on both sides of said waveguide port (14), respectively.

8. The waveguide microstrip transition structure according to claim 1, wherein said waveguide aperture (14) has a rectangular cross section.

9. Waveguide microstrip transition structure according to claim 1, characterized in that said probe (2) comprises: a substrate (21), a microstrip circuit layer (22) and a grounding metal layer (23); the substrate (21) is located between the microstrip circuit layer (22) and the grounding metal layer (23), the microstrip circuit layer (22) is the top layer of the probe (2), the grounding metal layer (23) is the bottom layer of the probe (2), and the microstrip circuit layer (22) faces the short-circuit block (3).