A round coaxial connector male and quasi-rectangular female interconnection fitting structure

Abstract

The application relates to an interconnecting adapter structure of a round coaxial connector male head and a quasi-rectangular female head, which comprises a round coaxial connector male head, a rectangular micro coaxial female head and a locking member; a first inner conductor in the round coaxial connector male head extends beyond the end face of a first outer conductor to form a center pin; the end part of a second inner conductor of the rectangular micro coaxial female head is provided with a pincer-shaped opening, the center pin is inserted into the pincer-shaped opening to be in electrical contact with the second inner conductor, the round coaxial connector male head and the rectangular micro coaxial female head are connected in an embedded mode, the locking member is used for fixedly connecting the rectangular micro coaxial female head with the bearing part, and a shielding layer is formed at the connecting position of the round coaxial connector male head and the rectangular micro coaxial female head; the application realizes low-loss and low-reflection signal transition between the round coaxial connector male head and the rectangular micro coaxial female head in a DC-170GHz frequency band, and has the advantages of simple structure, reliable plugging, strong assembly tolerance, and advantages suitable for closed testing application of micro coaxial devices.

Description

Technical Field

[0001] This invention relates to the field of microwave and radio frequency circuit technology, and specifically to an interconnection adapter structure for a round coaxial connector male head and a rectangular female head. Background Technology

[0002] With the rapid development of applications such as millimeter-wave communication, automotive radar, and satellite payload testing, operating frequencies have shifted from the microwave band to the terahertz band (e.g., 170 GHz and above). This increase in frequency places more stringent demands on transmission line loss, dispersion, and shielding performance. In the terahertz band, rectangular microcoaxial lines have become widely used in the design of microwave devices and modules due to their inherent advantages, including a fully enclosed metal structure, TEM mode transmission, no dielectric loss, and no cutoff frequency. Filters, couplers, antennas, and other devices based on rectangular microcoaxial lines exhibit excellent performance in the terahertz band.

[0003] As terahertz devices based on rectangular microcoaxial lines are increasingly applied in engineering, performance testing and verification have become critical engineering challenges. Using open test structures such as probe stations introduces spatial radiation coupling between signal ports and crosstalk between probes, making it impossible to accurately characterize the intrinsic electrical properties of the device under test. Furthermore, the probe contact state significantly affects test results, leading to poor repeatability between different operators. To avoid these problems, the signal ports of the microcoaxial device can be connected to the test system via a standard 0.5mm circular coaxial connector, allowing the test signal to be transmitted within a completely enclosed coaxial structure, thus eliminating radiation losses and crosstalk errors introduced by the open structure.

[0004] However, the aforementioned transition connection faces the following technical challenges in the terahertz band: First, the signal wavelength is extremely short (approximately 1.76 mm for 170 GHz), making it highly sensitive to processing accuracy and assembly errors. To achieve a mating fit, the inner conductor end of the rectangular microcoaxial female connector needs to be locally widened to accommodate the male connector's center pin. This widening area alters the cross-sectional dimensions of the inner conductor, leading to a decrease in the cutoff frequency of higher-order modes, and imposing stringent requirements on the geometric control of the widened area. Second, the cross-sectional shape and electromagnetic field distribution of the circular coaxial connector, such as a three-dimensional cylindrical symmetrical structure, and the rectangular microcoaxial connector, such as a quasi-planar rectangular structure, are fundamentally different. Direct connection will introduce severe mode mismatch and impedance discontinuity. Furthermore, the characteristics of their higher-order modes differ; the TE11 mode of the circular coaxial connector and the TE10 / TE01 mode of the rectangular microcoaxial connector are prone to mode coupling and parasitic transmission in the transition region.

[0005] Therefore, in the existing technology, there is a lack of effective interconnection structure between the three-dimensional circular coaxial male connector and the quasi-planar rectangular micro-coaxial female connector for the DC-170GHz ultra-wideband. This makes it impossible to effectively suppress the generation and transmission of higher-order modes, resulting in difficulty in achieving high-quality signal transition and maintaining single-mode transmission of the TEM master mode in this frequency band. Summary of the Invention

[0006] This invention provides an interconnection and mating structure between a round coaxial connector male head and a rectangular female head.

[0007] Other features and advantages of the invention will become apparent from the following detailed description, or may be learned in part by practice of the invention.

[0008] According to a first aspect of the present invention, an interconnection adapter structure for a circular coaxial connector male and a rectangular-like female connector includes: A male circular coaxial connector includes a first outer conductor and a first inner conductor. A first inner cavity is formed inside the first outer conductor. The first inner conductor is located inside the first inner cavity and is separate from the first inner cavity. The first inner conductor extends to the outside of the end face of the first outer conductor to form a center pin. A bearing portion is provided on the end face of the first outer conductor along the extension direction of the center pin. A rectangular micro coaxial female connector includes a second outer conductor and a second inner conductor. The second outer conductor has a second inner cavity, and the second inner conductor is located inside the second inner cavity but separate from it. The end of the second inner conductor has a clamp-shaped opening. The second outer conductor can extend along the support portion into the end face of the first outer conductor so that the round coaxial connector male connector and the rectangular micro coaxial female connector can be fitted and connected. The center pin extends into the clamp-shaped opening of the second inner conductor to electrically connect the first inner conductor and the second inner conductor. A locking member is provided, which can pass through the second outer conductor along the support portion to lock the first outer conductor and the second outer conductor together, and the locking member and the support portion form a shielding layer at the connection between the first outer conductor and the second outer conductor.

[0009] In some exemplary embodiments, the end face of the first outer conductor is provided with an annular groove around the central pin, and the end face of the second outer conductor connected to the first outer conductor is provided with an annular step portion. The annular step portion and the annular groove can fit together to make the first outer conductor and the second outer conductor electrically connected.

[0010] In some exemplary embodiments, both the annular groove and the annular step portion are rectangular ring structures.

[0011] In some exemplary embodiments, the supporting part further includes a first limiting post and a second limiting post, which are respectively located on both sides of the center pin. The first limiting post and the second limiting post are respectively provided with guide grooves on the side of the first limiting post and the side of the second limiting post closer to the center pin. The second outer conductor is provided with positioning ears on both sides. The positioning ears on both sides of the second outer conductor can be displaced along the guide grooves so that the second outer conductor is positioned and connected to the first outer conductor.

[0012] In some exemplary embodiments, the first limiting post and the second limiting post are respectively provided with pin holes along the vertical direction of the guide groove and passing through the guide groove; The locking component includes a shielding block, a first locking pin, and a second locking pin. The first locking pin and the second locking pin are respectively connected to both ends of the shielding block. After the positioning ears on both sides of the second outer conductor are engaged with the guide groove, the first locking pin and the second locking pin pass through the positioning ears and the guide groove along the pin hole and are inserted into the first limiting post and the second limiting post to limit the second outer conductor. When the first locking pin and the second locking pin are inserted into the pin hole, the shielding block spans the first limiting post and the second limiting post and is in contact with the second outer conductor.

[0013] In some exemplary embodiments, both the guide groove and the positioning ear are rectangular structures. The positioning ear has a notch that mates with the pin hole, and the positioning ear and the guide groove are interference-fitted. When the positioning ear and the guide groove are connected, the notch and the pin hole form a complete hole structure.

[0014] In some exemplary embodiments, the clamp-shaped opening is located inside the second inner cavity and is axially spaced by a predetermined distance from the end face of the second outer conductor.

[0015] In some exemplary embodiments, the second inner conductor includes a conventional segment and a clamping segment connected to each other, the clamping opening being located at the end of the clamping segment away from the conventional segment, and the outer width of the clamping opening being greater than the width of the conventional segment.

[0016] In some exemplary embodiments, the opening width of the clamp-shaped opening is greater than the width of the center pin, and the inner bottom of the clamp-shaped opening is a planar structure, and the width of the end of the center pin embedded in the clamp-shaped opening is the same as the width of the inner bottom of the clamp-shaped opening.

[0017] In some exemplary embodiments, an interconnection adapter structure for a cylindrical coaxial connector male and a rectangular female is provided, the structure being used for the mutual mating connection of a cylindrical coaxial connector male and a rectangular female.

[0018] The three-dimensional circular coaxial connector male and quasi-planar rectangular micro-coaxial female adapter structure provided in this application of the present invention achieves self-alignment and tight fit of the inner conductor by inserting the center pin of the circular coaxial connector male into the clamp-shaped opening at the end of the inner conductor of the rectangular micro-coaxial female, utilizing the guiding bevel at the end of the clamp-shaped opening and the flat section at the bottom. The circular coaxial connector male and the rectangular micro-coaxial female achieve full-ring grounding contact of the outer conductor through interlocking, and the carrier part achieves precise alignment and fixation of the circular coaxial connector male and the rectangular micro-coaxial female during assembly. Combined with the locking component, a shielding layer is formed at the interconnection adapter, further reducing the sensitivity of assembly errors to high-frequency transmission performance and improving assembly robustness. Through the above structure, this application achieves low-loss signal access and fully enclosed shielded interconnection between the circular coaxial connector male and the rectangular micro-coaxial female in the DC-170GHz frequency band, and has the advantages of simple structure, reliable insertion, strong assembly tolerance, and suitability for closed testing applications of micro-coaxial devices.

[0019] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit the invention. Attached Figure Description

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention. It is obvious that the drawings described below are merely some embodiments of the invention, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0021] Figure 1 An exploded view schematically illustrating an exemplary embodiment of the present invention shows an interconnection adapter structure of a round coaxial connector male head and a rectangular female head; Figure 2 A perspective view of a male circular coaxial connector in an exemplary embodiment of the present invention is shown schematically. Figure 3 This schematically illustrates a cross-sectional view of the male AA connector of a circular coaxial connector in an exemplary embodiment of the present invention. Figure 4 This schematically illustrates a cross-sectional view of the male BB connector of a circular coaxial connector in an exemplary embodiment of the present invention. Figure 5 This schematically illustrates the fabrication process of the three-dimensional electrochemical microstructure of the rectangular micro-coaxial mother head in an exemplary embodiment of the present invention; Figure 6 A perspective view of a rectangular micro-coaxial female connector in an exemplary embodiment of the present invention is shown schematically. Figure 7 A perspective view of a rectangular micro coaxial female connector in an exemplary embodiment of the present invention is shown schematically. Figure 8This schematically illustrates a CC cross-sectional view of a rectangular micro-coaxial female connector in an exemplary embodiment of the present invention; Figure 9 This schematic diagram illustrates the inner conductor structure of a rectangular micro-coaxial female connector in an exemplary embodiment of the present invention. Figure 10 A perspective view of a bridge-type locking member in an exemplary embodiment of the present invention is shown schematically. Figure 11 This schematically illustrates an assembly perspective view of the mating structure between the male round coaxial connector and the female rectangular micro coaxial connector in an exemplary embodiment of the present invention. Figure 12 This schematically illustrates an exemplary embodiment of the present invention. Figure 11 Cross-sectional view of DD in the middle; Figure 13 This schematically illustrates an exemplary embodiment of the present invention. Figure 11 EE cross-section; Figure 14 The diagram illustrates the S-parameter simulation results of an interconnection adapter structure between a circular coaxial connector male and a rectangular female connector, according to an exemplary embodiment of the present invention.

[0022] In the figure, 1 is the male connector of the circular coaxial connector; 10 is the first outer conductor; 100 is the annular groove; 101 is the bearing part; 102 is the limiting post; 103 is the pin hole; 104 is the guide groove; 11 is the first inner conductor; 110 is the center pin; 2 is the female connector of the rectangular micro coaxial connector; 20 is the second outer conductor; 200 is the annular step part; 201 is the positioning ear; 202 is the notch; 203 is the release hole; 21 is the second inner conductor; 210 is the clamp opening; 22 is the dielectric support bar; 3 is the bridge-type locking element; 31 is the locking pin; 32 is the shielding block. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0024] To enable those skilled in the art to better understand and implement the technical solutions of the present invention, the technical solutions of the present invention will be clearly and thoroughly described below in conjunction with the accompanying drawings.

[0025] It should be further noted that, in the description of this invention, the terms center, longitudinal, transverse, length, width, thickness, up, down, front, back, left, right, vertical, horizontal, top, bottom, inside, outside, clockwise, counterclockwise, axial, radial, circumferential, etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0026] Furthermore, it should be understood that in the description of the embodiments of the present invention, unless otherwise stated, / means or, for example, A / B can mean A or B: and / or in the text is merely a description of the association relationship of related objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of the present invention, multiple means two or more.

[0027] The terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first," "second," "third," or "fourth" may explicitly or implicitly include one or more of that feature, and in the description of this invention, unless otherwise stated, "multiple" means two or more.

[0028] Existing transition connection structures still have the following problems in the terahertz band: First, the signal wavelength is extremely short (approximately 1.76 mm for 170 GHz), making it highly sensitive to processing accuracy and assembly errors. To achieve a mating fit, the inner conductor end of the rectangular microcoaxial female connector needs to be locally widened to accommodate the male connector's center pin. This widening area changes the cross-sectional dimensions of the inner conductor, leading to a decrease in the cutoff frequency of higher-order modes, and imposing stringent requirements on the geometric control of the widened area. Second, the cross-sectional shape and electromagnetic field distribution of circular coaxial connectors (three-dimensional cylindrical symmetrical structure) and rectangular microcoaxial connectors (quasi-planar rectangular structure) are fundamentally different, and direct connection will introduce severe mode mismatch and impedance discontinuity. In addition, the characteristics of their higher-order modes are different (circular coaxial TE11 mode, rectangular microcoaxial TE10 / TE01 mode), and mode coupling and parasitic transmission are prone to occur in the transition region. Therefore, the design of the adapter structure needs to effectively suppress the generation and transmission of higher-order modes, and ensure that only the TEM main mode is maintained for single-mode transmission within the DC-170GHz operating frequency band. Currently, there is no mature solution for the interconnection structure between the three-dimensional circular coaxial male connector and the quasi-planar rectangular micro-coaxial female connector for the DC-170GHz frequency band.

[0029] To address the shortcomings and deficiencies of existing technologies, this example embodiment provides an interconnection adapter structure for a circular coaxial connector male and a quasi-rectangular female connector. This solves the problem that existing technologies lack an interconnection adapter structure for a three-dimensional circular coaxial male and a quasi-planar rectangular micro-coaxial female connector for the DC-170GHz ultra-wideband, which makes it difficult to achieve high-quality signal transition and maintain single-mode transmission of the TEM master mode in this frequency band. The structure provided in this example can be applied to millimeter-wave communication, automotive radar, and satellite payload testing.

[0030] The functions of each component in the adapter structure for a three-dimensional circular coaxial connector male and a quasi-planar rectangular micro coaxial female, applicable to the terahertz frequency band, will now be described in more detail with reference to the accompanying drawings and embodiments.

[0031] This example embodiment provides an adapter structure for a three-dimensional circular coaxial connector male and a quasi-planar rectangular micro coaxial female, applicable to the terahertz frequency band.

[0032] refer to Figure 1 As shown, Figure 1 An exploded view of an interconnection adapter structure between a circular coaxial connector male and a rectangular female connector provided in an embodiment of this application, as shown below. Figure 1 As shown, the interconnect adapter structure includes: The male connector 1 of the circular coaxial connector includes a first outer conductor 10 and a first inner conductor 11. A first inner cavity is formed inside the first outer conductor 10. The first inner conductor 11 is located inside the first inner cavity and is separate from the first inner cavity. The first inner conductor 11 extends to the outside of the end face of the first outer conductor 10 to form a center pin 110. A bearing portion 101 is provided on the end face of the first outer conductor 10 along the extending direction of the center pin 110. The rectangular micro coaxial female connector 2 includes a second outer conductor 20 and a second inner conductor 21. The second outer conductor 20 has a second inner cavity, and the second inner conductor 21 is located in the second inner cavity and is separate from the second inner cavity. The end of the second inner conductor 21 has a clamp-shaped opening 210. The second outer conductor 20 can extend into the end face of the first outer conductor 10 along the support part 101 so that the first outer conductor 10 and the second outer conductor 20 are fitted and connected. The center pin 110 extends into the clamp-shaped opening 210 of the second inner conductor 21 so that the first inner conductor 11 and the second inner conductor 21 are electrically connected. The locking member can pass through the second outer conductor 20 along the support portion 101 so that the first outer conductor 10 and the second outer conductor 20 are locked together, and the locking member and the support portion 101 form a shielding layer at the connection between the first outer conductor 10 and the second outer conductor 20.

[0033] In this example, the adapter structure for a round coaxial connector male and a rectangular micro-coaxial female is achieved by inserting the center pin 110 of the round coaxial connector male 1 into the clamp-shaped opening 210 at the end of the inner conductor of the rectangular micro-coaxial female 2. The guide bevel at the end of the clamp-shaped opening and the flat section at the bottom enable self-alignment and tight contact between the first inner conductor 11 and the second inner conductor 21. The rectangular micro-coaxial female 2 and the round coaxial connector male 1 achieve full-ring grounding contact between the first outer conductor 10 and the second outer conductor 20 through interlocking, and the carrier portion assists the first outer conductor 10 in this connection. The precise alignment and fixation during assembly with the second outer conductor 20, combined with the shielding layer formed by the locking components, creates a continuous shield above the mating end face, further reducing the sensitivity of assembly errors to high-frequency transmission performance and improving assembly robustness. Through the above structure, this embodiment of the application achieves low-loss signal access and fully enclosed shielded interconnection between the three-dimensional circular coaxial male connector and the quasi-planar rectangular microcoaxial female connector in the DC-170GHz frequency band, combining the advantages of simple structure, reliable plug-in, strong assembly tolerance, and suitability for enclosed testing applications of microcoaxial devices.

[0034] The following describes in more detail the various parts of the interconnection and adaptation structure between the male connector of the three-dimensional circular coaxial connector and the quasi-planar rectangular micro coaxial female connector, using specific implementation methods.

[0035] It should be noted that, in order to meet the testing requirements of the DC-170GHz frequency band, this application embodiment uses a 0.5mm standard circular coaxial connector. This 0.5mm coaxial connector is a standard interface launched by the industry to cover the DC-250GHz frequency band, which can effectively cover the DC-170GHz working frequency band required by this application. The male of the circular coaxial connector uses a section of circular coaxial transmission line at the tail of the standard connector. The inner and outer conductors are connected by air as the medium. The cutoff frequency of the first higher mode TE11 is higher than 250GHz, ensuring that only the TEM main mode is transmitted in the entire working frequency band. The characteristic impedance is 50Ω.

[0036] refer to Figures 2 to 4 As shown, optionally, the male round coaxial connector 1 includes a first outer conductor 10 and a first inner conductor 11, with the first inner conductor 11 disposed inside the first outer conductor 10. Air serves as the medium between them, forming a 50Ω coaxial transmission line at the tail of a 0.5mm standard round coaxial connector. The first outer conductor 10 extends along the mating end face to form a support portion 101, and a limiting post 102 is provided on the support portion 101. The support portion 101 and the limiting post 102 are used to support and fix the rectangular micro-coaxial female connector 2. The limiting post 102 has a pin hole 103 along the axial direction and a guide groove 104 along the horizontal direction. The support portion 101, the limiting post 102, and the first outer conductor 10 are an integral structure to ensure common grounding. The first inner conductor 11 of the male round coaxial connector 1 extends beyond the end face of the first outer conductor 10 to form a center pin 110.

[0037] In this embodiment, the first inner conductor 11 of the male connector 1 of the circular coaxial connector has a diameter of 218 μm and is located in the first inner cavity inside the first outer conductor. The first inner cavity has a corresponding diameter of 500 μm. The center pin 110 extends from the end face of the first inner conductor 11 with an extension length of 200 μm and a diameter of 160 μm. The first inner conductor 11 and the center pin 110 directly transition to a thinner profile through a diameter reduction stage.

[0038] The vertical distance between the upper surface of the support portion 101 and the axis of the center pin 110 is equal to the vertical distance from the center of the second inner conductor 21 of the rectangular micro coaxial female head 2 to the bottom surface of its second outer conductor 20. When the rectangular micro coaxial female head 2 is placed on the support portion 101, the axis of the center pin 110 and the central axis of the inner conductor 21 are at the same horizontal height to ensure accurate alignment of the male and female insertion.

[0039] Optionally, the support part 101 further includes a first limiting post and a second limiting post, which are located on both sides of the center pin 110. The first limiting post and the second limiting post are respectively provided with guide grooves 104 on the side of the first limiting post and the second limiting post near the center pin 110. The second outer conductor 20 is provided with positioning ears 201 on both sides. The positioning ears 201 on both sides of the second outer conductor 20 can be displaced along the guide grooves 104 so that the second outer conductor is positioned and connected to the first outer conductor.

[0040] In this embodiment, the support portion 101 is provided with two limiting posts 102, which are located on both sides of the support portion 101 in the width direction. The limiting posts 102 have guide grooves 104 on the side facing the rectangular micro coaxial female head 2. The guide grooves 104 extend axially and their dimensions are adapted to the dimensions of the positioning ears 201. When the rectangular micro coaxial female head 2 is placed on the support portion 101, the rectangular micro coaxial female head 2 is clamped between the two limiting posts 102, and the two are in close contact and limited. At the same time, the positioning ears 201 and the guide grooves 104 cooperate with each other to constrain the lateral displacement of the rectangular micro coaxial female head 2 on the support portion 101.

[0041] In this embodiment, the limiting post 102 is a rectangular block structure, with its height matching that of the rectangular micro-coaxial female head 2, and its length and width in the horizontal direction are both 1.2 mm. A guide groove 104 is formed on the side of the limiting post 102 facing the rectangular micro-coaxial female head; the guide groove 104 is a rectangular groove that penetrates the limiting post horizontally. A pin hole 103 is formed at the center of the limiting post 102 for the locking pin of the bridge-type locking component 3 to pass through. The pin hole 103 is a cylindrical hole, perpendicular to the bearing part 101 and penetrating both the limiting post and the bearing part, with a diameter of 0.8 mm.

[0042] It should be noted that the limiting post 102 in this embodiment mainly has the following two functions: First, the limiting function. The limiting post achieves Y-direction positioning by clamping the second outer conductor 20, constrains Z-direction displacement by the guide groove 104, and achieves X-direction fixation by locking the positioning ear 101 with the locking member, thus completing three-dimensional limiting and locking; Second, it improves grounding continuity. The limiting post 102 itself is a metal structure and is integrally connected with the bearing part 101 and the outer conductor 10. When the locking member spans above the two limiting posts, the limiting post forms an electrical connection between the locking member and the bearing part and the outer conductor, thereby constructing a complete grounding loop at the mating end face, improving grounding continuity, reducing the sensitivity of high-frequency transmission performance to assembly errors, and improving assembly robustness.

[0043] Optionally, the end face of the first outer conductor 10 is provided with an annular groove 100 around the central pin 110, and the end face of the second outer conductor 20 connected to the first outer conductor 10 is provided with an annular step portion 200. The annular step portion 200 and the annular groove 100 can fit together to make the first outer conductor 10 and the second outer conductor 20 electrically connected; both the annular groove 100 and the annular step portion 200 are rectangular ring structures.

[0044] In this embodiment, the first outer conductor 10 has an annular groove 100 on its end face that mates with the micro coaxial female connector. Specifically, the annular groove is a rectangular groove with an inner rectangular groove having a width of 500 μm and a height of 600 μm, and an outer rectangular groove having a width of 700 μm and a height of 800 μm. The depth of the annular groove is 120 μm, which is greater than the extension length of the annular step portion 200 of the rectangular micro coaxial female connector. This ensures that when the male and female connectors mate, the annular step portion 200 will not prematurely contact the bottom of the annular groove 100, thus limiting the insertion depth of the center pin 101, allowing the center pin 101 to be fully inserted into the clamp-shaped opening to a preset position.

[0045] It should be noted that, in this embodiment, the rectangular micro-coaxial transmission line generally consists of a metal outer conductor, a metal inner conductor, and dielectric support strips. The metal inner conductor is suspended within a rectangular cavity enclosed by the metal outer conductor, and is supported by dielectric support strips periodically arranged along the transmission direction. Specifically, the dielectric support strips penetrate the inner conductor in a direction perpendicular to the transmission line axis, with both ends embedded in the outer conductor to achieve fixation and coaxial alignment of the inner conductor within the cavity.

[0046] refer to Figure 6 As shown, the rectangular microcoaxial transmission line is integrally fabricated using a three-dimensional electrochemical microstructure additive manufacturing process. The main steps of this process include: spin-coating photoresist on a wafer, defining the pattern using a photomask, electroplating copper to form the structural layer, and planarizing the surface to obtain a smooth surface; after each layer is fabricated, the above steps are repeated to continue stacking on the existing layers, growing additively layer by layer until all layers are fabricated; finally, the photoresist and sacrificial layer material are removed to release the device structure. This process can achieve integral fabrication of microcoaxial structures with complex three-dimensional contours at the micrometer scale, enabling the precise fabrication of irregular geometric features such as clamp-shaped openings, annular steps, and flared sections. This avoids assembly errors and interface discontinuities caused by separate processing and reassembly, thereby ensuring the alignment accuracy between the metal inner conductor and the center pin, reducing transmission loss in the terahertz band, and providing a reliable implementation path for the transition structure between terahertz quasi-planar rectangular microcoaxial connectors and three-dimensional circular coaxial connectors. To adapt to the three-dimensional micro-coaxial fabrication process, the rectangular micro-coaxial metal outer conductor is provided with several release holes 202 for discharging the dissolved photoresist waste liquid during the device fabrication process. It should be noted that the number of release holes 202 should not be too many or too few. Too many will cause electromagnetic leakage, while too few will result in incomplete removal of photoresist and residue. The number should be determined after comprehensive consideration in the design.

[0047] Furthermore, to ensure that the rectangular microcoaxial cable transmits only the TEM primary mode and does not generate higher-order mode transmission within the entire DC-170GHz frequency band, the dimensions of the rectangular microcoaxial cable in this embodiment are configured such that the cutoff frequencies of both the TE10 and TE01 modes are higher than 170GHz. Preferably, the outer metal conductor has a cavity width of 565μm and a cavity height of 600μm, while the inner conductor has a width of 265μm and a height of 200μm. With these dimensions, the characteristic impedance of the rectangular microcoaxial cable is approximately 50Ω, and it transmits only the TEM primary mode within the DC-170GHz frequency band.

[0048] refer to Figures 4 to 7As shown, in this embodiment, the rectangular micro-coaxial female connector 2 is integrally formed from the aforementioned rectangular micro-coaxial line, including a second outer conductor 20 and a second inner conductor 21. The second inner conductor 21 is suspended within the rectangular second cavity enclosed by the second outer conductor 20, and is supported by dielectric support strips 22 arranged periodically along the transmission direction. The end of the second inner conductor 21 of the rectangular micro-coaxial female connector 2 is provided with a clamp-shaped opening 210 for forming a male-female mating with the center pin 110 of the round coaxial connector male connector to achieve tight contact of the inner conductor. The second outer conductor 20 of the rectangular micro-coaxial line is provided with an annular step portion 200 on the mating end face. The annular step portion 200 is formed by the second outer conductor 20 protruding outward from the mating end face and is used to insert into the annular groove 100 opened on the outer conductor end face of the round coaxial connector male connector 1 to achieve electrical contact and grounding between the first outer conductor 10 and the second outer conductor 20.

[0049] In this embodiment, the annular stepped portion 200 is formed by extending 100 μm outward from the mating end face along the axial direction. The annular stepped portion 200 is a rectangular annular boss, and its outer dimension is smaller than that of the outer conductor body, so that the outer conductor forms a constricted structure at the mating end face; through the continuous circumferential fitting between the annular stepped portion and the annular groove, the outer conductor achieves full-ring grounding contact, which can effectively reduce the impact of radial offset on signal transmission during assembly and improve assembly tolerance.

[0050] Optionally, both the guide groove 104 and the positioning ear 201 are rectangular structures. The positioning ear 201 has a notch 202 that mates with the pin hole, and the positioning ear 201 and the guide groove 104 are interference-fitted. When the positioning ear 201 and the guide groove 104 are connected, the notch 202 and the pin hole form a complete hole structure.

[0051] In this embodiment, a positioning ear 201 is provided on each side of the second outer conductor 20 of the rectangular micro-coaxial female connector 2, and the two positioning ears 201 are arranged opposite each other along the width direction of the second outer conductor 20. The positioning ear 201 is a rectangular block structure that protrudes outward from the side wall of the second outer conductor 20, and its front end face is flush with the mating end face of the second outer conductor 20 and extends axially. To adapt to the three-dimensional electrochemical microstructure additive manufacturing process, the thickness of the positioning ear 201 is consistent with the thickness of the second inner conductor 21, and its axial position corresponds to that of the second inner conductor 21. The width of the positioning ear 201 is adapted to the width of the guide groove 104 on the limiting post 102, and is used to form a sliding fit with the guide groove 104.

[0052] The positioning ear 201 has a notch 202. Preferably, the notch 202 is a semi-cylindrical notch that penetrates the positioning ear along the thickness direction of the positioning ear 201. During assembly, the notch 202 is aligned with the pin hole 103 on the limiting post 102 to form a channel through which the locking pin 31 passes.

[0053] Optionally, the second inner conductor 21 includes a regular segment and a clamping segment connected to each other. The clamping opening 210 is located at the end of the clamping segment away from the regular segment, and the outer width of the clamping opening 210 is greater than the width of the regular segment. The clamping opening 210 is located inside the second inner cavity and is axially spaced by a predetermined distance from the end face of the second outer conductor 20.

[0054] In this embodiment, the maximum width of the inner conductor in the region where the clamp-shaped opening 210 is located is 340 μm, which is greater than the width of the conventional section of the second inner conductor 21, which is 265 μm. A predetermined axial distance is maintained between the bottom end of the clamp-shaped opening 210 and the mating end face to improve the impedance discontinuity caused by structural abrupt changes at the male and female mating end faces, thereby achieving low-reflection signal transmission.

[0055] Optionally, the opening width of the clamp-shaped opening 210 is greater than the width of the center pin 110, and the inner bottom of the clamp-shaped opening 210 is a planar structure. The width of the end of the center pin 110 embedded in the clamp-shaped opening 210 is the same as the width of the inner bottom of the clamp-shaped opening 210.

[0056] In this embodiment, the clamp-shaped opening 210 has an overall V-shaped opening structure with a flat bottom. The width of the flat bottom is adapted to the diameter of the center pin 110 to form a tight electrical contact with the center pin 110. The opening width of the clamp-shaped opening 210 is greater than the width of the flat bottom, so that the clamp-shaped opening gradually narrows from the opening end to the bottom, guiding the center pin to be inserted and accurately aligned with the flat bottom area. Specifically, the width of the flat bottom is 160 μm, the diameter of the center pin 111 is 160 μm, and the two are fitted with zero clearance. The opening width of the clamp-shaped opening 210 is 184 μm.

[0057] It should be noted that, in the region where the clamp-shaped opening 210 is located, the second inner cavity of the second outer conductor 20 is provided with a flared section along the axial direction. The inner cavity size of the flared section gradually increases towards the end to match the widening of the conductor in the region where the clamp-shaped opening 210 is located. A constricted section is also provided at the mating end face of the second outer conductor 20, and the annular step portion 201 is located at the end of this constricted section. Through the cooperation of the flared and constricted sections, the second inner cavity of the second outer conductor 20 first expands and then shrinks towards the end from the conventional section, thereby optimizing the electric field distribution between the inner and outer conductors and improving impedance matching characteristics.

[0058] Optionally, the locking component includes a shielding block 32, a first locking pin, and a second locking pin. The first locking pin and the second locking pin are respectively connected to both ends of the shielding block 32. After the positioning ears 201 on both sides of the second outer conductor 20 are engaged with the guide groove 104, the first locking pin and the second locking pin pass through the pin hole through the positioning ears 201 and the guide groove 104, respectively, and are inserted into the first limiting post and the second limiting post to limit the second outer conductor 20. When the first locking pin and the second locking pin are inserted into the pin hole, the shielding block 32 spans the first limiting post and the second limiting post and is in contact with the second outer conductor.

[0059] In this embodiment, reference Figure 10 As shown, the locking component in this embodiment is a bridge-type locking component 3, including two locking pins 31 and a shielding block 32 connected between the two locking pins 31. The two locking pins 31 and the shielding block 32 are integrally formed. The bridge-type locking component 3 is generally bridge-shaped, with the two locking pins 31 located at both ends of the bridge-type locking component, and the shielding block 32 connected between the tops of the two locking pins.

[0060] Specifically, the locking pin 31 is a cylindrical structure, the diameter of which is adapted to the diameter of the channel formed by the pin hole 103 on the limiting post 102 and the notch 202 on the positioning ear 201. It is used to pass through the channel and fix the rectangular micro coaxial female head 2 to the bearing part 101. The shielding block 32 is a plate-shaped structure, spanning above the two limiting posts 102. When the locking pin 31 is inserted into the channel, the shielding block 32 covers the limiting post 102 and the positioning ear 201, forming a continuous grounding shield at the mating end face.

[0061] The following description, in conjunction with the assembly process of an interconnection adapter structure for a circular coaxial connector male and a rectangular female, further illustrates this embodiment. (Refer to...) Figures 8 to 13 As shown, the assembly process is as follows: During assembly, the rectangular micro-coaxial female head 2 is placed on the support part 101. First, the rectangular micro-coaxial female head 2 is pushed horizontally along the axial direction into the mating end face of the round coaxial male head 1. The positioning ear 201 is pushed horizontally along the guide groove 104. During the pushing process, the center pin first enters the opening part of the clamp-shaped opening and automatically slides towards the bottom flat area for centering under the guidance of the inclined surfaces on both sides of the clamp-shaped opening. At the same time, the annular step part 200 is embedded in the annular groove 100 to achieve continuous circumferential grounding of the outer conductor. When the center pin 110 is fully pushed into the flat area of ​​the clamp-shaped opening, the center pin 110 and the flat bottom form a zero-gap fit, achieving electrical contact between the first inner conductor 11 and the second inner conductor 21. At the same time, the annular step part 200 is embedded in the preset position of the annular groove 100 to achieve continuous circumferential grounding of the first outer conductor 10 and the second outer conductor 20. The semi-cylindrical notch 202 on the positioning ear 201 is aligned with the pin hole 103 on the limiting post 102, forming a channel for the locking pin to pass through. The two locking pins 31 of the bridge-type locking member 3 pass through the corresponding pin holes 103 and are engaged in the notch 202, fixing the rectangular micro coaxial female head 2 to the bearing part 101, thus completing the mating connection between the round coaxial male head 1 and the rectangular micro coaxial female head 2.

[0062] In this embodiment, the assembled structure is subjected to simulation design experiments, with reference to... Figure 14 As shown, the circular coaxial connector male and rectangular micro-coaxial female adapter structure provided in this embodiment has a return loss of better than 20dB and an insertion loss of less than 0.2dB in the DC-170GHz full frequency band. It realizes low-loss and low-reflection signal transition between the rectangular micro-coaxial line and the standard circular coaxial connector. It has the advantages of simple structure, reliable insertion, high tolerance to assembly error, and suitability for closed test applications of interconnection between micro-coaxial devices and coaxial connectors.

[0063] Compared with the prior art, the adapter structure of the three-dimensional circular coaxial connector male and the quasi-planar rectangular micro-coaxial female provided in this application achieves self-alignment and tight fit of the inner conductor by inserting the center pin of the circular coaxial connector male into the clamp-shaped opening 210 at the end of the inner conductor of the rectangular micro-coaxial female. The guiding slope at the end of the clamp-shaped opening and the flat section at the bottom are used to achieve self-alignment and tight fit of the inner conductor. The outer conductor end face of the rectangular micro-coaxial female is provided with an annular step portion that is embedded in the annular groove at the end face of the circular coaxial connector male. The circumferential continuous fitting between the annular step and the groove achieves full-ring grounding contact of the outer conductor. The limiting post on the bearing part cooperates with the positioning ear on the outer conductor of the micro-coaxial female to achieve precise alignment and fixation during assembly. Combined with the shielding block of the bridge-type locking part, a continuous shield is formed above the mating end face, which further reduces the sensitivity of assembly errors to high-frequency transmission performance and improves assembly robustness. With the above structure, this application achieves low-loss signal access and fully enclosed shielded interconnection between the male round coaxial connector and the female rectangular micro-coaxial connector in the DC-170GHz frequency band. It has the advantages of simple structure, reliable plug-in, strong assembly tolerance, and suitability for enclosed testing applications of micro-coaxial devices.

[0064] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

[0065] Other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention herein. This application is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of the invention are indicated by the claims.

[0066] It should be understood that the present invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. An interconnection and mating structure for a circular coaxial connector male head and a rectangular-shaped female head, characterized in that, include: A male circular coaxial connector includes a first outer conductor and a first inner conductor. A first inner cavity is formed inside the first outer conductor. The first inner conductor is located inside the first inner cavity and is separate from the first inner cavity. The first inner conductor extends to the outside of the end face of the first outer conductor to form a center pin. A bearing portion is provided on the end face of the first outer conductor along the extension direction of the center pin. A rectangular micro coaxial female connector includes a second outer conductor and a second inner conductor. The second outer conductor has a second inner cavity, and the second inner conductor is located inside the second inner cavity but separate from it. The end of the second inner conductor has a clamp-shaped opening. The second outer conductor can extend along the support portion into the end face of the first outer conductor so that the round coaxial connector male connector and the rectangular micro coaxial female connector can be fitted and connected. The center pin extends into the clamp-shaped opening of the second inner conductor to electrically connect the first inner conductor and the second inner conductor. A locking member is provided, which can pass through the second outer conductor along the support portion to lock the first outer conductor and the second outer conductor together, and the locking member and the support portion form a shielding layer at the connection between the first outer conductor and the second outer conductor.

2. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 1, characterized in that, The end face of the first outer conductor has an annular groove around the central pin, and the end face of the second outer conductor connected to the first outer conductor has an annular step portion. The annular step portion fits into the annular groove to make the first outer conductor and the second outer conductor electrically connected.

3. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 2, characterized in that, Both the annular groove and the annular step are rectangular ring structures.

4. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 1, characterized in that, The supporting part further includes a first limiting post and a second limiting post, which are located on both sides of the center pin. The first limiting post and the second limiting post are respectively provided with guide grooves on the side of the first limiting post and the second limiting post closer to the center pin. The second outer conductor is provided with positioning ears on both sides. The positioning ears on both sides of the second outer conductor can be displaced along the guide grooves so that the second outer conductor is positioned and connected to the first outer conductor.

5. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 4, characterized in that, The first limiting post and the second limiting post are respectively provided with pin holes along the vertical direction of the guide groove and passing through the guide groove; The locking component includes a shielding block, a first locking pin, and a second locking pin. The first locking pin and the second locking pin are respectively connected to both ends of the shielding block. After the positioning ears on both sides of the second outer conductor are engaged with the guide groove, the first locking pin and the second locking pin pass through the positioning ears and the guide groove along the pin hole and are inserted into the first limiting post and the second limiting post to limit the second outer conductor. When the first locking pin and the second locking pin are inserted into the pin hole, the shielding block spans the first limiting post and the second limiting post and is in contact with the second outer conductor.

6. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 5, characterized in that, Both the guide groove and the positioning ear are rectangular structures. The positioning ear has a notch that mates with the pin hole, and the positioning ear and the guide groove are interference fit. When the positioning ear and the guide groove are connected, the notch and the pin hole form a complete hole structure.

7. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 1, characterized in that, The second inner conductor includes a regular segment and a clamping segment connected to each other. The clamping opening is located at the end of the clamping segment away from the regular segment, and the outer width of the clamping opening is greater than the width of the regular segment.

8. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 1, characterized in that, The clamp-shaped opening is located inside the second inner cavity and is axially spaced at a predetermined distance from the end face of the second outer conductor.

9. The interconnection and mating structure of a circular coaxial connector male head and a rectangular female head according to claim 1, characterized in that, The opening width of the clamp-shaped opening is greater than the width of the center pin, and the inner bottom of the clamp-shaped opening is a planar structure. The width of the end of the center pin embedded in the clamp-shaped opening is the same as the width of the inner bottom of the clamp-shaped opening.

10. An interconnection and mating structure for a circular coaxial connector male head and a rectangular-like female head, characterized in that, The structure is used for the mating connection of a cylindrical coaxial connector male and a rectangular female connector.

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