Miniaturized broadband matching single-ridge waveguide 90-degree bend

Abstract

This disclosure relates to the field of single-ridge waveguides, specifically to a miniaturized broadband matched 90-degree bend in a single-ridge waveguide. The bend includes a first waveguide segment and a second waveguide segment that are separated from each other. A separate matching mechanism is provided between the first and second waveguide segments. The separate matching mechanism includes a multi-stage matching section and an L-shaped matching section that are separated from each other. The multi-stage matching section is connected to the first waveguide segment, and the L-shaped matching section is connected to the second waveguide segment. The multi-stage matching section is used to match the real part of the impedance, and the L-shaped matching section is used to match the imaginary part of the impedance. The first and second waveguide segments are arranged at a 90-degree spatial angle. The first and second waveguide segments are perpendicular to each other at a 90-degree angle, and their positions present a spatial angle due to their separation. A separate ridge structure is used between the first and second waveguide segments. Specifically, the ridge of the first waveguide segment and the ridge of the second waveguide segment are located on non-adjacent sides.

Description

Technical Field

[0001] This disclosure relates to the field of single-ridge waveguides, and more specifically, to a miniaturized broadband matched 90-degree bend in a single-ridge waveguide. Background Technology

[0002] Single-ridge waveguides, as an important type of microwave transmission line, are widely used in the design of high-performance filters, directional couplers, and other microwave systems due to their advantages such as wide operating bandwidth, long cutoff wavelength (facilitating miniaturization), and low characteristic impedance (easy to achieve matching). Existing traditional single-ridge waveguides, such as... Figure 8 As shown. Currently, there are two main forms for realizing single-ridge waveguides, but they each have inherent defects that are difficult to overcome, as follows: (1) Circular arc gradual bend: The existing structure of the circular arc gradual bend is as follows: Figure 9 As shown, this is the most classic and common type of bend, which achieves a 90-degree turn through a circular arc waveguide with a constant radius of curvature. The advantages of this structure are smooth electromagnetic wave transmission, high mode purity, and the ability to achieve good matching and a low voltage standing wave ratio (VSWR) at a sufficiently large bending radius. However, its disadvantage is its large size. To obtain excellent broadband performance, the radius of curvature of the arc usually needs to be comparable to, or even larger than, that of the waveguide, resulting in a significant increase in the physical size of the bend and making it unsuitable for miniaturized applications with stringent space requirements.

[0003] (2) Right-angle chamfered elbow: The existing structure of the right-angle chamfered elbow is as follows: Figure 10 As shown, the simulation results of the existing right-angle tangent elbow are as follows: Figure 11 As shown, to overcome the large size of circular arc bends, right-angle chamfered bends have emerged. This structure employs a near-right-angle hard bend, with chamfering and matching components added to the inside of the bend to compensate for discontinuities, thereby achieving impedance matching. The advantage of this structure is its relatively compact size and small physical dimensions. However, the inherent disadvantage of right-angle chamfered bends is their narrow bandwidth, and the reactance introduced by the right-angle bend exhibits discontinuities. Even with optimization of the chamfer and the addition of matching components, the optimization space is very limited, typically achieving acceptable performance only within a narrow frequency band. This makes it almost impossible to match the broadband advantage of ridge waveguide components, becoming a bottleneck in the system's matching bandwidth.

[0004] In summary, while traditional circular arc bends offer good performance, their physical size is too large; and while right-angle chamfered bends reduce size, their matching bandwidth is narrow, making them unsuitable for broadband applications and contradicting the broadband usage scenarios of ridge waveguides. Summary of the Invention

[0005] To address the problems existing in the prior art, this disclosure proposes a miniaturized broadband-matched single-ridge waveguide 90-degree bend, aiming to overcome the technical challenge that existing single-ridge waveguide 90-degree bend structures cannot simultaneously achieve miniaturization and broadband high performance. The technical solution adopted in this disclosure is as follows: This disclosure provides a miniaturized broadband matched single-ridge waveguide 90-degree bend, the bend comprising: a first waveguide segment and a second waveguide segment that are separated from each other, and a separate matching mechanism is provided between the first waveguide segment and the second waveguide segment; The split matching mechanism includes a multi-stage matching section and an L-shaped matching section, and the multi-stage matching section and the L-shaped matching section are separated from each other. The multi-stage matching section is connected to the first waveguide segment, and the L-shaped matching section is connected to the second waveguide segment.

[0006] Preferably, the multi-stage matching section is used to match the real part of the impedance, and the L-shaped matching section is used to match the imaginary part of the impedance.

[0007] Preferably, the first waveguide segment and the second waveguide segment are arranged at a 90-degree spatial angle. The first waveguide segment and the second waveguide segment are perpendicular to each other at 90 degrees, and their positions present a spatial angle due to their separation from each other.

[0008] Preferably, a split ridge structure is adopted between the first waveguide segment and the second waveguide segment.

[0009] Preferably, the split ridge structure is specifically such that the "ridge" of the first waveguide segment and the "ridge" of the second waveguide segment are located on non-adjacent sides. As... Figure 1 , Figure 2 As shown, the "ridge" of the first waveguide segment and the "ridge" of the second waveguide segment are located on two non-adjacent sides, and they are separated from each other and have no direct adjacency.

[0010] Preferably, the multi-level matching section has a gradually curved surface and / or a stepped surface. The shape design of the multi-level matching section preferably follows the minimum reflection theory.

[0011] Preferably, the L-shaped mating section includes an inductive boss and a capacitive boss.

[0012] Preferably, the capacitive boss is in close contact with the waveguide wall of the bend.

[0013] Preferably, the capacitive boss is further connected to the second waveguide segment.

[0014] Preferably, the elbow is a passive reciprocal device. The first waveguide segment and the second waveguide segment can be interchanged, specifically: when the first waveguide segment acts as the input waveguide segment, the second waveguide segment acts as the output waveguide segment; when the first waveguide segment acts as the output waveguide segment, the second waveguide segment acts as the input waveguide segment.

[0015] The beneficial effects of this disclosure are as follows: By setting a separate matching mechanism between the first and second waveguide sections, this disclosure enables the miniaturization of the 90-degree bend while maintaining excellent broadband matching performance. This meets the broadband matching requirements of single-ridge waveguides in miniaturized applications, overcoming the technical challenge of existing single-ridge waveguide 90-degree bend structures failing to simultaneously achieve miniaturization and high broadband performance. Because the bend provided by this disclosure is a passive reciprocal device, the functions of the first and second waveguide sections can be interchanged, providing better adaptability and scalability compared to existing technologies.

[0016] In this disclosure, the first waveguide segment and the second waveguide segment are arranged at a 90-degree spatial angle and have a separate ridge structure. This makes the implementation of this disclosure have the advantages of a relatively compact structure and relatively small physical size, similar to a right-angle bend. It also avoids the reactance discontinuity introduced by the right-angle bend due to the right angle turn, and has a large bandwidth optimization space, which can match the broadband advantage of single-ridge waveguide components.

[0017] In this disclosure, the split matching mechanism is divided into mutually separate multi-stage matching sections and L-shaped matching sections. The multi-stage matching sections are connected to the first waveguide segment, and the L-shaped matching sections are connected to the second waveguide segment. The L-shaped matching section includes inductive bosses and capacitive bosses. The multi-stage matching sections adopt a gradually curved surface and / or a stepped surface, so that the shape design of the multi-stage matching sections preferably follows the minimum reflection theory, further improving the performance of this disclosure. The L-shaped matching section is subdivided into inductive bosses and capacitive bosses to compensate for the equivalent reactance of discontinuity effects. Because it avoids the existing technology that relies solely on reducing capacitive reactance to optimize matching, this disclosure does not require a large size and has a wide bandwidth, achieving broadband matching with ridge waveguide components. Therefore, this disclosure simultaneously possesses the advantages of existing traditional arc-shaped bends and right-angle chamfered bends, while perfectly avoiding their disadvantages. This disclosure employs both inductive and capacitive bosses to compensate for discontinuity effects in the equivalent reactance. This avoids the limitations of existing technologies that rely solely on reducing capacitive reactance for matching optimization. It also eliminates the need for larger dimensions and achieves a wider bandwidth, thus matching the broadband advantages of ridge waveguide components. Therefore, this disclosure combines the advantages of existing conventional arc-shaped bends and right-angle chamfered bends while perfectly avoiding their disadvantages. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the specific embodiments of this disclosure or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the structure of the single-ridge waveguide 90-degree bend described in this disclosure.

[0020] Figure 2 This is a cross-sectional schematic diagram of the 90-degree bend of the single-ridge waveguide described in this disclosure.

[0021] Figure 3 This is a current line distribution diagram of the inductive boss described in this disclosure.

[0022] Figure 4 This is a diagram showing the electric field distribution of the capacitive boss described in this disclosure.

[0023] Figure 5 This is a schematic diagram illustrating the change in the equivalent area of ​​the parallel electric walls in this disclosure.

[0024] Figure 6 This is a schematic diagram illustrating the alteration of the spacing between parallel electric walls in this disclosure.

[0025] Figure 7 The simulation results of the elbow provided in this disclosure.

[0026] Figure 8 This is a schematic diagram of the structure of an existing traditional single-ridge waveguide.

[0027] Figure 9 This is a schematic diagram of the existing arc-shaped gradual bend.

[0028] Figure 10 This is a schematic diagram of an existing right-angle bend.

[0029] Figure 11 The simulation results are shown in the figure for an existing right-angle bend. Detailed Implementation

[0030] The present disclosure will now be described in detail with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the present application can be combined with each other.

[0031] To enable those skilled in the art to better understand the technical solutions in one or more embodiments of this specification, the technical solutions in one or more embodiments of this specification will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this specification, and not all of the embodiments. Based on one or more embodiments of this specification, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of this document.

[0032] like Figure 1-2 As shown, a miniaturized broadband matched single-ridge waveguide 90-degree bend includes: a first waveguide section 100 and a second waveguide section 200 that are separated from each other, and a separate matching mechanism 300 is provided between the first waveguide section 100 and the second waveguide section 200. The split matching mechanism 300 includes a multi-stage matching section 310 and an L-shaped matching section 320, and the multi-stage matching section 310 and the L-shaped matching section 320 are separated from each other. The multi-stage matching section 310 is connected to the first waveguide segment 100, and the L-shaped matching section 320 is connected to the second waveguide segment 200.

[0033] In one feasible embodiment, the multi-stage matching section 310 is used to match the real part of the impedance, and the L-shaped matching section 320 is used to match the imaginary part of the impedance.

[0034] In one feasible embodiment, the first waveguide segment 100 and the second waveguide segment 200 are arranged at a 90-degree spatial angle. For example... Figure 1 , Figure 2 As shown, the first waveguide segment 100 and the second waveguide segment 200 are perpendicular to each other at 90 degrees, and their positions present a spatial angle due to their separation from each other.

[0035] In one feasible embodiment, a split ridge structure is used between the first waveguide segment 100 and the second waveguide segment 200.

[0036] Furthermore, the split ridge structure specifically means that the "ridge" of the first waveguide segment 100 and the "ridge" of the second waveguide segment 200 are located on non-adjacent sides. As... Figure 1 , Figure 2 As shown, the "ridge" of the first waveguide segment 100 and the "ridge" of the second waveguide segment 200 are located on two non-adjacent sides, and they are separated from each other and have no direct adjacency.

[0037] By utilizing the 90-degree spatial angle arrangement between the first waveguide segment 100 and the second waveguide segment 200 and the separated ridge structure, this disclosure, when applied to a single-ridge waveguide, possesses the advantages of a relatively compact structure and small physical size, similar to a right-angle bend. It also avoids the reactance discontinuity introduced by the right-angle bend, offering greater bandwidth optimization potential and matching the broadband advantages of single-ridge waveguide components. Compared to the 90-degree spatial bend of a traditional integrated ridge structure, the separated ridge structure provided by this disclosure allows the 90-degree bend to still achieve a 90-degree electric field turn within a minimal size, significantly reducing the structural size required for a slow electric field turn.

[0038] In one feasible embodiment, the multi-level matching section 310 has a shape that employs a gradient curved surface and / or a stepped surface. The shape design of the multi-level matching section 310 preferably follows the minimum reflection theory.

[0039] Furthermore, the shape of the multi-level matching section 310 is preferably a Chebyshev gradient stepped surface. For example... Figure 2 As shown, the shape of the multi-level matching section 310 is demonstrated using a Chebyshev gradient stepped surface.

[0040] In common knowledge, a Chebyshev stepped surface can actually function as a Chebyshev multi-stage impedance transformer, with each matching stage acting as a separate impedance transformer. Because the Chebyshev multi-stage impedance transformer has an equal-ripple passband, its total reflection coefficient is expressed as: (1) In equation (1), This represents the total reflection coefficient of the Chebyshev multi-stage impedance transformer. T N This represents the characteristic impedance of the Nth matching section.

[0041] To achieve 80% matching bandwidth—that is, S within the passband 11 ≤-20dB, in this embodiment, N=2 is set. Substituting into equation (1), we get: (2) Solving The characteristic impedance ratios for each stage can be obtained by referring to tables. For example, when N=0, ln(Z1)=4.051; when N=1, ln(Z2)=4.259. After solving for the characteristic impedance through electromagnetic simulation, the characteristic impedances corresponding to each matching section can be obtained. 80% of the matching bandwidth and the S in the passband... 11 The correspondence between ≤-20dB is common knowledge and will not be elaborated here.

[0042] The electromagnetic simulation solution process can be specifically described as follows: The characteristic impedance T of the Nth-level matching section is obtained by looking up a table.N Then, the reflection coefficient corresponding to the Nth level matching section can be calculated. N The reflection coefficients at each level are obtained. Then, the characteristic impedance Z of each matching section can be recursively calculated using the following equation (3). N : (3) Wherein, the initial value Z0 is the characteristic impedance of the first waveguide segment 100, which is used to substitute into equation (3) for auxiliary calculation; Z N The characteristic impedance of the Nth matching section; N The reflection coefficient of the Nth matching section; And N≧0, but the calculation when N=0 0 and Z0 only participate in auxiliary calculations, and are only calculated when N>=1. N Z N As the reflection coefficient and characteristic impedance corresponding to the Nth level matched section.

[0043] After obtaining the characteristic impedances corresponding to each matching section, the physical dimensions of each matching section can be synthesized using electromagnetic simulation software, and finally the physical dimension values ​​of the multi-stage matching section 310 can be obtained by summarizing them.

[0044] Furthermore, the multi-level matching section 310 includes at least two levels of matching sections.

[0045] Furthermore, the L-shaped matching section 320 includes an inductive boss 321 and a capacitive boss 322. This disclosure simultaneously employs both inductive and capacitive bosses 321 and 322 to compensate for discontinuities in the equivalent reactance. This avoids the prior art's reliance solely on reducing capacitive reactance for matching optimization, eliminates the need for a large size, and achieves a wider bandwidth, thus realizing broadband matching with ridge waveguide components. Therefore, this disclosure possesses the advantages of both conventional arc-shaped bends and right-angle bends, while perfectly avoiding their disadvantages.

[0046] Figure 3 The diagram shows the current line distribution of the inductive boss 321. When the inductive boss 321 is loaded, a clear change in the current line can be observed. Therefore, the inductive boss 321 can be equivalent to an inductive reactance. This is due to the split ridge structure, which makes the position of the inductive boss 321 free of equivalent electric walls, so that the behavior of the inductive boss 321 is inductively loaded.

[0047] Furthermore, the capacitive boss 322 is closely attached to the waveguide wall of the elbow.

[0048] Furthermore, the capacitive boss 322 is also connected to the second waveguide segment 200.

[0049] Figure 4 The diagram shows the electric field distribution of the capacitive boss 322. Since the electric field lines are densely distributed at the capacitive boss 322, and the edges of all the electric field lines are observed to bend under capacitive loading, the composition of the discontinuous capacitive reactance in the bend can be adjusted simply by changing the width W1 and length L1 of the capacitive boss 322.

[0050] The capacitive loading of capacitive boss 322 is similar to that of a parallel plate capacitor, and the formula for calculating its capacitance is as follows: ; Where C is the capacitive size of capacitive boss 322, A is the equivalent area of ​​parallel electric walls, d is the distance between parallel electric walls, and ε represents the dielectric constant of the dielectric.

[0051] It should be noted that there are two ways to change the capacitive reactance of capacitive boss 322: (1) change the size of the equivalent area A of the parallel electric wall, such as Figure 5 As shown; (2) Change the distance d between the parallel electric walls, such as Figure 6 As shown.

[0052] As Figure 5 , Figure 6 As shown, W1 is the width of the capacitive boss 322, L1 is the length of the capacitive boss 322, W2 is the width of the inductive boss 321, L2 is the length of the inductive boss 321, and the parallel electric walls refer to the two opposing and parallel electric walls between the L-shaped matching section 320 and the multi-stage matching section 310. d is the distance between these two electric walls – simply called the "parallel electric wall spacing," and A is the effective coverage area of ​​the opposing portion between the two electric walls – simply called the "equivalent area." The equivalent area A of the parallel electric walls, the parallel electric wall spacing d, etc., can be understood by referring to the parallel plate capacitor.

[0053] Furthermore, the width W1 of the capacitive boss 322 is preferably equal to the ridge width of the second waveguide segment 200.

[0054] Since adjusting both the width W1 and length L1 of the capacitive boss 322 can change the capacitive reactance, the width W1 of the capacitive boss 322 can be made as equal as possible to the ridge width of the output waveguide section. This further avoids impedance discontinuities in the interconnection. Given that the width W1 of the capacitive boss 322 is equal to or close to the ridge width of the second waveguide section 200, only the height of the capacitive boss needs to be adjusted subsequently, simplifying the design.

[0055] In one feasible embodiment, the elbow is a passive reciprocal device.

[0056] In one feasible embodiment, when the first waveguide segment 100 acts as an input waveguide segment, the second waveguide segment 200 acts as an output waveguide segment; When the first waveguide segment 100 acts as the output waveguide segment, the second waveguide segment 200 acts as the input waveguide segment.

[0057] Working principle: such as Figure 10 As shown, adding a chamfer in existing right-angle beveled elbows is equivalent to reducing the equivalent capacitive reactance in the discontinuity effect. However, the simulation results of right-angle beveled elbows are as follows... Figure 11 As shown, simply adding a chamfer cannot completely eliminate the presence of capacitive reactance, which results in a narrow matching bandwidth for the 90-degree bend of the traditional right-angle ridge waveguide, causing a loss of the system's operating bandwidth.

[0058] Unlike traditional techniques that rely solely on reducing capacitive reactance to optimize matching, this disclosure simultaneously introduces both inductive bosses 321 and capacitive bosses 322 to achieve equivalent reactance that compensates for discontinuities. For example... Figure 7 As shown in the simulation results, when operating at 3.9~7.1 GHz with S11≤-20dB, the relative bandwidth of the elbow provided by this disclosure can reach over 58%, with relative bandwidth = (7.1-3.9) / ((7.1+3.9) / 2) = 0.5818. Simulation experiments demonstrate that this disclosure can achieve 80% matching bandwidth (S11≤-20dB), and the operating bandwidth of the elbow provided by this disclosure is significantly greater than that of traditional existing technologies. Furthermore, the size of the elbow provided by this disclosure is sufficiently small to meet the application requirements of miniaturized microwave modules.

[0059] In summary, the miniaturized broadband-matched single-ridge waveguide 90-degree elbow provided in this disclosure achieves both miniaturization and excellent broadband matching performance by setting a separate matching mechanism between the first and second waveguide sections. This solves the broadband matching requirement of single-ridge waveguides in miniaturized applications. Because the elbow provided in this disclosure is a passive reciprocal device, the functions of the first and second waveguide sections can be interchanged, providing better adaptability and scalability compared to existing technologies.

[0060] In this disclosure, the first waveguide segment and the second waveguide segment are arranged at a 90-degree spatial angle and have a separate ridge structure. This makes the implementation of this disclosure have the advantages of a relatively compact structure and relatively small physical size, similar to a right-angle bend. It also avoids the reactance discontinuity introduced by the right-angle bend due to the right angle turn, and has a large bandwidth optimization space, which can match the broadband advantage of single-ridge waveguide components.

[0061] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure and not to limit them. Although this disclosure has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this disclosure. Any modifications or equivalent substitutions that do not depart from the spirit and scope of this disclosure should be covered within the protection scope of the claims of this disclosure.

Claims

1. A miniaturized broadband matched single-ridge waveguide 90-degree bend, characterized in that, The elbow includes a first waveguide section (100) and a second waveguide section (200) that are separated from each other. A separate matching mechanism (300) is provided between the first waveguide section (100) and the second waveguide section (200). The separate matching mechanism (300) includes a multi-stage matching section (310) and an L-shaped matching section (320). The multi-stage matching section (310) and the L-shaped matching section (320) are separated from each other. The multi-stage matching section (310) is connected to the first waveguide section (100), and the L-shaped matching section (320) is connected to the second waveguide section (200). A split ridge structure is adopted between the first waveguide segment (100) and the second waveguide segment (200); The split ridge structure is specifically defined as follows: the "ridge" of the first waveguide segment (100) and the "ridge" of the second waveguide segment (200) are located on non-adjacent sides.

2. The single-ridge waveguide 90-degree bend according to claim 1, characterized in that, The multi-stage matching section (310) is used to match the real part of the impedance, and the L-shaped matching section (320) is used to match the imaginary part of the impedance.

3. The single-ridge waveguide 90-degree bend according to claim 1, characterized in that, The first waveguide segment (100) and the second waveguide segment (200) are arranged at a 90-degree spatial angle.

4. The single-ridge waveguide 90-degree bend according to claim 1, characterized in that, The shape of the multi-level matching section (310) adopts a gradient surface and / or a stepped surface.

5. The single-ridge waveguide 90-degree bend according to claim 4, characterized in that, The shape of the multi-level matching section (310) is a Chebyshev gradient stepped surface.

6. The single-ridge waveguide 90-degree bend according to claim 4, characterized in that, The multi-level matching section (310) includes at least two levels of matching sections.

7. The single-ridge waveguide 90-degree bend according to claim 6, characterized in that, The L-shaped matching section (320) includes an inductive boss (321) and a capacitive boss (322); The capacitive boss (322) is in close contact with the waveguide wall of the elbow; The capacitive boss (322) is also connected to the second waveguide segment (200).

8. The single-ridge waveguide 90-degree bend according to claim 7, characterized in that, The width of the capacitive boss (322) is equal to the ridge width of the second waveguide segment (200).

9. The single-ridge waveguide 90-degree bend according to claim 1, characterized in that, The elbow is a passive reciprocal device; When the first waveguide segment (100) acts as the input waveguide segment, the second waveguide segment (200) acts as the output waveguide segment; When the first waveguide segment (100) acts as the output waveguide segment, the second waveguide segment (200) acts as the input waveguide segment.

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