Multi-band Ridge Waveguide Module

Abstract

The present invention discloses a ridge waveguide module operating in multiple frequency bands. According to the present invention, a ridge waveguide module is provided comprising: an upper split block; a lower split block; and a ridge block disposed between the upper split block and the lower split block, wherein ridges protruding opposite each other are formed in the ridge block to define a ridge gap in the opening region of the propagation path of the upper and lower split blocks, and a circuit mounting portion is formed in the central region of the ridge block to remove the ridge gap so that a circuit is mounted in the E-plane direction.

Description

Technology Field

[0001] The present invention relates to a ridge waveguide module operating in multiple frequency bands, and more specifically, to a waveguide structure and circuit coupling technology for transmitting and coupling radio waves in microwave / millimeter wave / terahertz bands, and in particular, to a module that covers multiple standard bands with a single module based on a ridge waveguide and can replace and combine transition sections to a standard square waveguide. Background Technology

[0002] In microwave, millimeter wave, and ultra-high frequency (THz) band applications, waveguide modules containing low-noise amplifiers (LNAs) are widely used as key front-end components that determine reception sensitivity.

[0003] Commercial low-noise amplifier modules adopt standard square waveguide specifications (e.g., WR series) tailored to band characteristics and are provided as individual models corresponding to the frequency range supported by each product (e.g., 140-220 GHz, 210-280 GHz, 230-250 GHz, 250-350 GHz, etc.).

[0004] Due to these structural and specification characteristics, configuring a broadband system requires purchasing and operating different modules for each frequency band, which increases equipment costs and maintenance burdens as the number of modules grows. In particular, in ultra-high frequency bands such as THz, the unit cost of a single module is very high, resulting in excessive costs for building and verifying multi-band systems.

[0005] A typical form of conventional technology involves mounting an integrated circuit (IC) or PCB antenna onto a standard waveguide module for a single frequency band. Generally, the module body is machined into a split-block structure, and metal materials such as aluminum are used to form standard waveguide channel specifications. To mount circuits and components, pedestals are machined at the edges or center inside, where on-chip (or PCB) antennas / ICs are placed to combine transmitted and received signals. It is common practice to design the module with an edge air gap to prevent mechanical interference and damage between the chip and the module.

[0006] However, such pedestal-based mounting structures form substantial protrusions within the waveguide channel that obstruct propagation, potentially causing discontinuities (impedance mismatch, parasitic resonance, radiation loss, etc.) in modes propagating directly along the channel. Additionally, while air gaps are advantageous for mechanical protection, they complicate the path of the electromagnetic field at high frequencies, thereby limiting the matching bandwidth. Prior art literature

[0007] Republic of Korea Published Patent Application KR 10-2625433 B1 The problem to be solved

[0008] To solve the problems of the aforementioned prior art, the present invention proposes a ridge waveguide module operating in multiple frequency bands that can flexibly support multiple frequency bands with a single module. means of solving the problem

[0009] In order to achieve the above-mentioned purpose, according to one embodiment of the present invention, a ridge waveguide module is provided, comprising: an upper split block; a lower split block; and a ridge block disposed between the upper split block and the lower split block, wherein the ridge block has ridges formed protruding opposite each other to define a ridge gap in the opening region of the propagation path of the upper and lower split blocks, and a circuit mounting portion is formed in the central region of the ridge block to remove the ridge gap so that a circuit is mounted in the E-plane direction.

[0010] The above circuit includes a feed line on a planar substrate, and the feed line extends toward the ridge gap and can be electromagnetically coupled with the inside of the waveguide through the ridge gap.

[0011] The above ridge gap can be formed to be electrically shorted by the ridge cavity at the end passing through the circuit.

[0012] The above ridge cavity may be formed as a circular or substantially circular cavity.

[0013] The end of the above feed line is connected to a radial stub, and impedance matching at the circuit mounting part can be adjusted by adjusting the radius of the radial stub.

[0014] The above feed line can be positioned so as to be spaced apart from the surface of the ridge by the thickness of the substrate.

[0015] First and second standard square waveguide transition sections can be detachably coupled to the front and rear ends of the above-mentioned ridge waveguide module, respectively. Effects of the invention

[0016] According to the present invention, a circuit mounting surface is formed on a waveguide body including a ridge, and radio waves are coupled and propagated through a gap formed by the ridge, thereby having the advantage of being able to support multiple frequency bands with a single module. Brief explanation of the drawing

[0017] FIG. 1 is a perspective view of a ridge waveguide module according to one embodiment of the present invention. FIG. 2 is a plan view illustrating the circuit side coupling structure of a ridge waveguide module according to the present embodiment. Figures 3 and 4 are schematic diagrams illustrating the frequency extension concept of a ridge waveguide. FIGS. 5 to 7 are perspective views illustrating standard square waveguide switching sections mounted at the front and rear ends of a ridge waveguide module according to the present embodiment. Figure 8 is a diagram illustrating the configuration of a microstrip-ridge waveguide transition circuit. Figure 9 is a graph illustrating an example of the frequency characteristics of the proposed transition. Specific details for implementing the invention

[0018] The present invention is capable of various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the invention to specific embodiments, and it should be understood that the invention includes all modifications, equivalents, and substitutions that fall within the spirit and scope of the invention.

[0019] Furthermore, the components of the embodiments described with reference to each drawing are not limited to the respective embodiments and may be implemented to be included in other embodiments within the scope of maintaining the technical spirit of the present invention. It is also obvious that multiple embodiments may be re-implemented as a single embodiment that integrates multiple embodiments, even if a separate description is omitted.

[0020] Furthermore, in the description referring to the attached drawings, identical components are assigned the same or related reference numerals regardless of drawing symbols, and redundant descriptions thereof are omitted. In describing the present invention, if it is determined that a detailed description of related prior art could unnecessarily obscure the essence of the present invention, such detailed description is omitted.

[0022] FIG. 1 is a diagram illustrating the configuration of a ridge waveguide module according to a preferred embodiment of the present invention.

[0023] As illustrated in FIG. 1, the ridge waveguide module according to the present embodiment may include an upper split block (100), a lower split block (102), and a ridge block (104).

[0024] The upper split block (100) and the lower split block (102) are joined so as to face each other, and a ridge block (104) is placed between them.

[0025] In the ridge block (104) according to the present embodiment, ridges (112) protruding at opposing positions are formed so that a ridge gap (114) is formed in the area where the opening (110) of the propagation path of the upper and lower split blocks (100, 102) is formed.

[0026] Referring to FIG. 2, a circuit mounting portion (116) is formed in the central region of the ridge block (104) by removing the ridge gap (114) so ​​that a circuit (200), such as an IC chip, is mounted in the direction of the E-Plane.

[0027] The ridge gap (114) guides electromagnetic coupling to occur between the feed of the circuit (200) and the inside of the waveguide along the narrow path formed by the ridge (112).

[0028] That is, instead of placing the circuit on top of the pedestal which physically blocks the radio waves like a conventional standard waveguide, the circuit (200) is placed on the side of the ridge block (104) to utilize E-field concentration and coupling through the ridge gap (114).

[0029] The ridge gap (114) is formed to short-circuit in the form of a cavity through the circuit (200), thereby blocking further propagation after passing through the circuit (200) and suppressing unwanted radiation and parasitic resonance.

[0030] Figures 3 and 4 are diagrams illustrating the concept of frequency extension of a ridge waveguide.

[0031] Referring to FIGS. 3 and 4, a ridge structure with metal ribs protruding toward the E-plane inside a square waveguide electrically reduces the effective cross-section of the waveguide, thereby lowering the cutoff frequency and expanding the bandwidth of the first-order dominant mode (TE10).

[0032] By concentrating the electric field in the narrow ridge gap formed between the ridge and the opposite wall (or opposite ridge), single-mode propagation becomes possible over a wider frequency range even with waveguides of the same external dimensions, and as a result, it is easy to achieve broadband impedance matching.

[0033] For example, standard ridge waveguides such as the WRD-180 are standardized to enable dominant mode propagation in the 18-40 GHz range, and the band extension effect of the ridge can be confirmed by the fact that removing the ridge from a square waveguide of the same dimensions results in a relatively narrower dominant mode band. By appropriately designing the ridge gap, ridge height and width, and taper shape, the usage range of the TE10 dominant mode can be shifted up and down, and the generation threshold of higher-order modes (e.g., TE01, TE20) can be controlled to suppress mode interference and parasitic resonance.

[0034] Thanks to these characteristics, it is possible to design a single ridge structure to cover multiple standard bands (e.g., 18-50 GHz), such as K, Ka, and Q, but there are limitations in that the complex cross-sectional shape increases the demands for processing precision and surface quality.

[0035] The present invention improves manufacturing efficiency by inserting an upper and lower split block (100, 102) and a separate ridge block (104) in the middle, and combines the physical advantages of such a ridge waveguide with a circuit side coupling structure to realize broadband and low-loss transitions without large protrusions inside the channel, and achieves multi-standard band compatibility by simply replacing the transition sections at the front and rear ends.

[0036] FIGS. 5 to 7 illustrate a method of transitioning a ridge waveguide module according to the present embodiment into a standard square waveguide.

[0037] Referring to FIG. 5, a first standard waveguide transition section (502) is provided at the front end of the ridge waveguide module (500), and a second standard waveguide transition section (504) is provided at the rear end.

[0038] FIG. 5 is a diagram illustrating the case where the first standard waveguide transition section and the second standard waveguide transition section have a K linear taper structure, FIG. 6 has a Ka taper structure, and FIG. 7 has a Q taper structure.

[0039] Referring to FIGS. 5 to 7, the ridge waveguide module (500) forms a broadband waveguide channel including a ridge (112) and a ridge gap (114), and a standard square waveguide transition section (e.g., WR-series, 502, 504) corresponding to the band is detachably coupled to the front and rear ends through alignment pins and fastening bolts.

[0040] By selecting a transition section that matches the target frequency band and attaching it to the front and rear ends of the main body, the user can interface with two or more different standard bands (e.g., K, Ka, Q) using the same module main body.

[0041] Accordingly, the burden of traditionally having to prepare separate modules for each band in multi-band systems is reduced, and cost and operational efficiency are improved as band switching, recalibration, and maintenance can be performed by replacing only the transition section.

[0042] FIG. 8 is a schematic diagram showing the configuration of a microstrip-ridge waveguide transition circuit according to one embodiment of the present invention.

[0043] Referring to FIG. 8, a microstrip feed (feed line, 800) formed on a flat substrate of a circuit mounting portion (116) extends in the direction of a ridge gap (114) to perform E-planar coupling, and the ridge gap (114) after passing through the feed line (800) is terminated in a circular (or approximately circular) ridge cavity (802) to form an electrical short, thereby blocking the propagation of residual waves.

[0044] The ridge cavity (802) contributes to the optimization of the feed input impedance from a circuit perspective, in addition to the radio wave blocking function. The feed line (800) is positioned at a height spaced apart from the surface of the ridge (112) by the thickness of the substrate to induce electric field concentration inside the ridge gap (114), and the end passing through the ridge gap (114) is connected to an open-ended radial stub to achieve multi-band matching through the adjustment of the stub radius.

[0045] For example, the dimensions of FIG. 8 are illustrated based on a Duroid series approximately 5-mil substrate and a split block structure, and this transition is applicable to a module operating at 18-50 GHz (K, Ka, Q band).

[0046] With this configuration, it is possible to secure wideband and flat impedance characteristics while reducing insertion loss and mode conversion during the transition period.

[0047] Figure 9 is a graph showing an example of the frequency characteristics of the ridge waveguide transition of the present invention.

[0048] The left graph of Fig. 9 plots the insertion loss (left axis) and mismatch loss (right axis) of a single transition (simulation), showing that the insertion loss is generally less than 0.5 dB across the 18-50 GHz range.

[0049] The graph on the right shows the characteristics of a back-to-back configuration in which two transitions are connected by a simple transmission line, and it can be seen that the total insertion loss in the same band is maintained at less than 1 dB and the ripple within the band is small, ensuring broadband matching.

[0050] Therefore, the ridge waveguide transition according to the present embodiment exhibits low-loss and wide-band characteristics at both the individual unit and module levels, and is suitable for multi-band (e.g., K / Ka / Q) operation of the present invention.

[0051] The embodiments of the present invention described above are disclosed for illustrative purposes only, and those skilled in the art with ordinary knowledge of the present invention may make various modifications, changes, and additions within the spirit and scope of the present invention, and such modifications, changes, and additions should be considered to fall within the scope of the following claims.

Claims

Claim 1 A ridge waveguide module comprising: an upper split block; a lower split block; and a ridge block disposed between the upper split block and the lower split block, wherein ridges protruding opposite each other are formed in the ridge block to define a ridge gap in the opening region of the propagation path of the upper and lower split blocks, and a circuit mounting portion is formed in the central region of the ridge block to remove the ridge gap so that a circuit is mounted in the E-plane direction. Claim 2 A ridge waveguide module according to claim 1, wherein the circuit comprises a feed line on a planar substrate, and the feed line extends toward the ridge gap and is electromagnetically coupled with the interior of the waveguide through the ridge gap. Claim 3 In paragraph 2, the ridge gap is formed to be electrically shorted by the ridge cavity at the end passing through the circuit, forming a ridge waveguide module. Claim 4 In paragraph 3, the ridge cavity is a ridge waveguide module formed as a circular cavity. Claim 5 A ridge waveguide module according to paragraph 2, wherein the end of the feed line is connected to a radial stub, and impedance matching at the circuit mounting portion is adjusted by adjusting the radius of the radial stub. Claim 6 In paragraph 2, the feed line is a ridge waveguide module positioned so as to be spaced apart from the surface of the ridge by the thickness of the substrate. Claim 7 A ridge waveguide module according to claim 1, characterized in that a first and a second standard square waveguide transition section are detachably coupled to the front and rear ends of the ridge waveguide module, respectively.

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