Waveguide device

Abstract

To simply and efficiently connect a millimeter wave IC terminal with an antenna radiation element by a multichannel waveguide device.SOLUTION: In a waveguide device 1H, a high frequency circuit 10 having a transmission / reception terminal 11 and a signal ground (SG) terminal 12 is disposed on an upper surface side of a substrate 100, a first member 102 having a conductive lower surface electrically connected to the SG terminal 12 is disposed on a lower surface side of the substrate 100, a second member 200 having a conductive upper surface is disposed on the lower surface side thereof. A ridge 201 having a strip-shaped conductive upper surface is disposed on the upper surface side thereof, and a second waveguide 5 is formed between the conductive upper surface and a lower surface of the first member 102. There is a first waveguide 3C that penetrates the substrate 100 in a vertical direction, and is composed of a core conductor 300C and a peripheral conductor 103. An upper feeding part 302 is disposed on the substrate 100, and connects the transmission / reception terminal 11 and an upper end of the core conductor 300C at an electromagnetic wave level. A lower feeding conductor 300Cc, which is a lower end part of the core conductor 300C, is high-frequency coupled to a side surface of the end part of the ridge 201.SELECTED DRAWING: Figure 14A

Description

[Technical Field]

[0001] The present invention relates to a waveguide device. [Background technology]

[0002] In recent years, research and development into millimeter-wave sensing and communications has expanded, creating a demand for high-gain, low-loss, wideband, and multi-channel antennas. In response to this demand, progress has been made in the development of WRG (Waffle Iron Ridge waveGuide) technology, which is useful as a next-generation antenna and waveguide (see Patent Documents 1 and 2). Figure 3 of Patent Document 1 discloses the world's first basic structure of a WRG. Patent Document 2 discloses a subordinate ancillary structure, in which two conductive members constituting this basic structure are fixed outside the waveguide region, as one of the structures of a WRG for high-frequency bands such as millimeter waves.

[0003] One of the features of WRG technology is that in the multiple waveguides within the antenna, located from the millimeter-wave IC (MMIC: Monolithic Microwave Integrated Circuit) to the antenna radiating element that transmits and receives millimeter-wave electromagnetic waves, separation walls are formed to prevent mutual coupling between adjacent waveguides. This prevents leakage of propagating electromagnetic waves, maintaining transmission loss at the same level as metal waveguides and minimizing interference with electromagnetic waves transmitted through other adjacent waveguides. Conventional microstrip waveguides and microstrip antennas do not have such separation walls.

[0004] A major application of millimeter-wave antennas is imaging radar sensing, which has multiple transmit and receive channels. When using microstrip antennas for this purpose, in addition to the large losses in the waveguide, interference due to mutual coupling between adjacent waveguides and antenna radiating elements can occur, resulting in problems with target detection accuracy. On the other hand, using WRG technology for such multi-channel antennas not only significantly reduces losses in the waveguide, but also significantly reduces mutual coupling between waveguides within the antenna. Furthermore, using antenna radiating elements suitable for WRG, such as mini-horn antennas and slot antennas, can further reduce mutual coupling. This ensures accurate signal transmission and reception between the antenna radiating elements and the transmit and receive terminals of the millimeter-wave integrated circuit (IC) that transmits and receives these signals. As a result, in millimeter-wave radar sensing, for example, the target signal contained in the received electromagnetic waves from the target can be accurately detected, enabling accurate target detection.

[0005] With WRG technology, this separation wall is realized by magnetic walls provided on both sides of the ridge waveguide, specifically with a periodic structure such as a rod array. If this magnetic wall is realized with a single rod array, the separation effect can be expected to be about 30 dB. To further enhance this separation effect, if two rod arrays are provided between the two ridge waveguides, the separation effect can be expected to be about 40 dB, achieving high separation performance suitable for an array antenna.

[0006] Such magnetic walls have the function of confining electromagnetic waves in the corresponding frequency band. The structures that make up these walls are called artificial magnetic conductors (AMCs), and can be realized with structures other than rod arrays (see, for example, Patent Document 2). Specifically, the description in the middle of paragraph

[0015] of Patent Document 2 is helpful: "The texture or structure is often periodic or quasi-periodic and is designed to interact with waves so as to behave macroscopically as an artificial magnetic conductor (AMC), electromagnetic band gap (EBG) surface, or soft surface."

[0007] Future imaging radars using WRGs will increasingly have more transmit and receive channels for more accurate target detection. To increase the number of channels, millimeter-wave ICs with a corresponding number of transmit and receive terminals are used. A waveguide within the antenna, for example, is sometimes provided, connecting these transmit and receive terminals to the transmit and receive apertures (antenna radiating elements) in a one-to-one relationship. The millimeter-wave IC is typically mounted on a high-frequency circuit board and connected to the ridge waveguide of the WRG via a waveguide (usually a microstrip line) on the board. Conventionally, this connection has been achieved by mounting a transducer or other device on the board, connecting it to a rectangular waveguide, and then connecting this rectangular waveguide to the ridge waveguide of the WRG (see Patent Documents 3 and 4). In addition, in experiments using waveguide devices, a structure has been proposed in which the electromagnetic waves of the experimental subject are guided through a coaxial cable and connected to a ridge-shaped coaxial connector (see Non-Patent Document 1). [Prior art documents] [Patent documents]

[0008] [Patent Document 1] WO2003-065497(EP1331688) [Patent Document 2] Special Publication No. 2011-527171 [Patent Document 3] Japanese Patent Application Laid-Open No. 2011-120155 [Patent Document 4] Japanese Patent Application Publication No. 2018-207487 [Non-patent literature]

[0009] [Non-Patent Document 1] Per-Simon Kildal, Ashraf Uz Zaman, Eva Rajo-Iglesias, Esperanza Alfonso, Alejandro Valero-Nogueira, "Design and Experimental Verification of Ridge Gap Waveguide in Bed of Nails for Parallel Plate Mode Suppression", IET Microwaves, Antennas and Propagation, January 2009 Summary of the Invention [Problem to be solved by the invention]

[0010] The prior art of Patent Document 3 requires the provision of transducers and rectangular waveguides for each waveguide corresponding to each antenna radiating element. Increasing the number of transmit / receive channels increases the installation space required for these, resulting in a larger waveguide device. With the prior art of Patent Document 4, it is difficult to achieve stable connections between the terminals of a millimeter-wave IC mounted on a substrate and the ends of waveguides mounted within the substrate during mass production, etc. Furthermore, increasing the number of transmit / receive channels increases the installation space required for waveguides and other components, resulting in an increase in the substrate area around the millimeter-wave IC. Furthermore, the prior art of Non-Patent Document 1 requires coaxial connectors to be placed on the ridge waveguides to be connected. When this technique is applied to a waveguide device with a large number of transmit / receive channels, coaxial connectors must be placed on all corresponding ridge waveguides, and further coaxial connectors must be placed on the waveguides on each terminal side of the millimeter-wave IC that receives these, resulting in a larger device. The present invention has been made in consideration of the above-mentioned problems, and aims to provide a waveguide device that can connect a millimeter-wave IC terminal and an antenna radiating element simply, space-savingly, inexpensively, and efficiently, even in a waveguide device with a large number of channels. [Means for solving the problem]

[0011] The present invention provides a first waveguide comprising: a first member having an upper surface and a conductive lower surface; a second member disposed on the lower surface side of the first member and having a conductive upper surface; a core conductor that passes through the first member in the vertical direction and is not in contact with the conductive lower surface; and a peripheral conductor that is disposed around the core conductor via an insulator and along the core conductor and is in contact with the conductive lower surface of the first member; a ridge disposed between the first member and the second member and having a waveguide surface that is a strip-shaped conductive upper surface facing the conductive lower surface of the first member; The waveguide device is composed of a second waveguide formed by the waveguide surface of the ridge and the conductive lower surface of the first member, and an electromagnetic wave blocking wall arranged between the first member and the second member and adjacent to the second waveguide, wherein the lower end of the core conductor extending downward of the first member is connected by high-frequency coupling to an end side surface of the ridge arranged opposite to the lateral side of the lower end, and further includes a rod-shaped conductor or wall portion having a conductive side surface facing the end side surface across the lower end of the core conductor. In the above configuration, the rod-shaped conductor may have a gap between its upper surface and the conductive lower surface of the first member. In the above configuration, the rod-shaped conductor may have an upper surface in contact with the conductive lower surface of the first member.

[0012] In the above configuration, the rod-shaped conductor may be a wall portion whose upper surface is in contact with or high-frequency coupled to the conductive lower surface of the first member, and the width of the wall portion in the direction along which the ridge extends and in the direction perpendicular to the height direction may be equal to or greater than 1 / 4 of the free-space wavelength λo of the electromagnetic wave at the center frequency of the operating frequency band.

[0013] In the above configuration, the upper surface side of the first member may further include a substrate having an upper surface and a lower surface, the core conductor and the peripheral conductor penetrating vertically, a high-frequency circuit arranged on the upper surface or the upper side of the substrate and having a terminal for transmitting or receiving and a signal ground terminal, and an upper power supply section arranged on the upper surface of the substrate and electromagnetically connecting the terminal for transmitting or receiving of the high-frequency circuit and an end of the core conductor on the upper surface side of the substrate, wherein the signal ground terminal of the high-frequency circuit is in contact with the conductive lower surface of the first member. In the above configuration, the upper feeding portion may be a waveguide formed by a microstrip line, a coplanar line, or a post wall. In the above configuration, the upper power supply portion may be configured to bring the transmitting or receiving terminal of the high-frequency circuit into contact with the end of the core conductor on the upper surface side of the board, and to bring the signal ground terminal of the high-frequency circuit into contact with the peripheral conductor. In the above configuration, the core conductor and the peripheral conductor may each be made of a single conductor, and the single peripheral conductor may be disposed adjacent to the single core conductor. In the above configuration, the core conductor may be made of one conductor, the peripheral conductor may be made of two conductors, and the one core conductor may be disposed between the two peripheral conductors.

[0014] In the above configuration, the core conductor may consist of one conductor, the peripheral conductor may consist of multiple linear conductors, and the multiple peripheral conductors may be arranged along a portion of the outer periphery of the single core conductor, or half of the multiple peripheral conductors may be arranged along a portion of the outer periphery of the single core conductor, and the remaining half of the multiple peripheral conductors may be arranged along the periphery of another portion opposite to the portion of the outer periphery. In the above configuration, the core conductor may consist of one conductor, the peripheral conductor may consist of multiple linear conductors or multiple plate-shaped conductors, and the multiple peripheral conductors may be arranged along approximately the entire circumference of the single core conductor. In the above configuration, the core conductor may be made of one conductor, and the peripheral conductor may be made of one cylindrical conductor, and the peripheral conductor may be disposed so as to surround the outer periphery of the one core conductor. In the above configuration, the first member may be made up of a ground pattern formed on the lower surface of the substrate. [Effects of the Invention]

[0015] According to the present invention, even in a waveguide device with a large number of channels, it is possible to connect a millimeter-wave IC terminal and an antenna radiating element simply, space-savingly, inexpensively and efficiently. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a perspective view showing a schematic configuration example of a waveguide device 1 according to a first embodiment. [Figure 2] FIG. 2 is a diagram showing a schematic cross-sectional configuration taken along line AA' in FIG. [Figure 3] 1A is a top view of the WRG structure 4, FIG. 1B is a partial perspective view of the WRG structure 4, and FIG. 1C is a partial cross-sectional view taken along line BB' in FIG. [Figure 4A] 2 is a diagram showing an example of a connection configuration of each component of the IC mounting board 2, and is a partial top view of the IC mounting board 2 as seen from the upper surface side. FIG. [Figure 4B] 2 is a diagram showing an example of a connection configuration of each component of the IC mounting board 2, and is a partial bottom view of the IC mounting board 2 as seen from the bottom side. FIG. [Figure 4C] FIG. 1A is a diagram showing the structure of a microstrip line, FIG. 1B is a diagram showing the structure of a coplanar line, and FIG. 1C is a diagram showing the structure of a post-wall waveguide. [Figure 5] 1 is a diagram showing a schematic diagram of a basic structure of the present invention; [Figure 6] FIG. 10 is a perspective view showing a schematic configuration example of a waveguide device 1A according to a second embodiment. [Figure 7] FIG. 7 is a diagram schematically illustrating the configuration of a partial cross-sectional view taken along line AA' in FIG. [Figure 8]1(a) to 1(h) are top views showing structural examples of the first waveguide 3. FIG. [Figure 9] FIG. 1A is a partial perspective view showing an example of the configuration of high-frequency coupling, and FIG. 1B is a partial cross-sectional view taken along line AA' in FIG. [Figure 10] (a) is a side view showing an example of the configuration of a core conductor 310 used for high-frequency coupling, (b) is a diagram showing an example of the configuration of a first waveguide 3, and (c) is a partially cross-sectional oblique view showing an example of the connection configuration of the core conductor 310 to the substrate 100. [Figure 11] FIG. 9(b) is a cross-sectional view taken along line AA' in FIG. 9(a). [Figure 12] 11(a) to 11(d) are diagrams showing the electromagnetic field distribution in the configuration example of FIG. 10, where 11(a) and 11(c) are perspective views, 11(b) is a side view, and 11(d) is a front view. [Figure 13A] FIG. 2 is a cross-sectional view showing a schematic configuration example of a waveguide device 1B. [Figure 13B] FIG. 1 is a cross-sectional view showing a schematic configuration example of a waveguide device 1C. [Figure 13C] FIG. 10 is a top view of the WRG structure 4E. [Figure 13D] FIG. 13D is a cross-sectional view of the waveguide device 1D taken along line AA' in FIG. 13C. [Figure 14A] FIG. 10 is a cross-sectional view showing a schematic configuration example of a waveguide device 1H according to a third embodiment. [Figure 14B] 10 is a partial perspective view showing a state in which a first waveguide 3C according to a third embodiment is high-frequency coupled to a second waveguide 5. FIG. [Figure 14C] FIG. 14C is a partial cross-sectional view taken along line AA' in FIG. 14B. [Figure 14D] 14B is a diagram showing the results of a simulation of the transmission characteristics and reflection characteristics of the waveguide device 1H having the configuration shown in FIG. 14A. FIG. [Figure 14E] FIG. 1 is a cross-sectional view showing a schematic configuration example of a waveguide device 1K. [Figure 14F] FIG. 1 is a cross-sectional view showing a schematic configuration example of a waveguide device 1L. [Figure 15] 10A and 10B are schematic diagrams showing examples of structures for matching impedances between a first waveguide and a second waveguide by changing the thickness of a ridge, etc. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0017] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are merely examples of means for realizing the present invention, and may be modified or changed as appropriate depending on the configuration of the device to which the present invention is applied and various conditions. The present invention is not limited to the following embodiments. In the following drawings, identical or similar parts are denoted by identical or similar reference numerals. It should be noted, however, that the drawings are schematic and conceptual, and the vertical and horizontal dimensions and scales of components or parts differ from those of the actual parts. Therefore, specific dimensions and scales should be determined with reference to the following explanation. Of course, the drawings also include parts with different dimensional relationships and ratios. 〔term〕

[0018] "Millimeter waves" refer to electromagnetic waves with frequencies in the range of 30 GHz to 300 GHz. The wavelength of "millimeter waves" in a vacuum is in the range of 1 mm to 10 mm. Electromagnetic waves with wavelengths in the range of 10 mm to 30 mm are sometimes called "quasi-millimeter waves." The frequency band handled by the waveguide device of the present disclosure may be a band with a lower frequency than millimeter waves, or may be a band with a higher frequency than millimeter waves. The waveguide device may be used, for example, to propagate electromagnetic waves in the terahertz wave band (approximately 300 GHz or higher and 3 THz or lower).

[0019] A "high frequency circuit" is a semiconductor integrated circuit chip or package that generates or processes high frequency waves in the millimeter wave band. A "package" is a package that includes one or more semiconductor integrated circuit chips that generate or process high frequency waves in the millimeter wave band. A millimeter wave IC in which one or more millimeter wave ICs are integrated on a single semiconductor substrate is particularly called an MMIC (Monolithic Microwave Integrated Circuit). In this disclosure, examples using an "MMIC" as the "millimeter wave IC" will be mainly described. Furthermore, a "high frequency circuit" also includes, for example, a circuit composed of Schottky diodes used in a chemical reaction path and a high-power magnetron used for power transmission.

[0020] The package corresponds to a surface-mount type package. Examples include those with an L-shaped terminal configuration, such as SOP (Small Outline Package) and QFP (Quad Flat Package), and those with a J-shaped terminal configuration, such as SOJ (Small Outline J-leaded package) and QFJ (Quad Flat J-leaded package). In addition, it includes those with electrode pad terminal configurations, such as QFN (Quad Flat Non-leaded package) and LGA (Land Grid Array), and those with needle-shaped terminal configurations, such as PGA (Pin Grid Array). It also includes those with solder ball terminal configurations, such as BGA (Ball Grid Array) and EBGA (Enhanced BGA). An "IC mounting board" refers to a mounting board on which a millimeter-wave IC is mounted, and includes a "millimeter-wave IC" and a "substrate" as components. A simple "substrate" refers to a mounting board without a millimeter-wave IC mounted on it. [Basic configuration of the present invention]

[0021] FIG. 5 is a schematic diagram illustrating the basic structure of the present invention. In a waveguide device 1 according to the present invention, as shown in FIG. 5, a high-frequency circuit 10 having a transmitting or receiving terminal 11 and a signal ground terminal 12 is disposed on or near the top surface of a substrate 100. A first member 102 having a conductive upper surface that is electrically connected to the signal ground terminal 12 of the high-frequency circuit 10 is disposed along the bottom surface of the substrate 100. A second member 200 having a conductive upper surface is disposed along the bottom surface of the first member 102. In the waveguide device 1, a ridge 201 having a strip-shaped conductive upper surface is disposed on or near the top surface of the second member 200. Although not shown, a plurality of rods that function as electromagnetic wave shielding walls are disposed on both sides of the ridge 201 in the direction in which it extends (see, for example, rods 202 in FIG. 3). A second waveguide 5 is formed between the conductive upper surface of the ridge 201 and the bottom surface of the first member 102.

[0022] The substrate 100 has a first waveguide 3 penetrating in the vertical direction, which is composed of a core conductor 300 and a peripheral conductor 103. An upper feed part 302 is arranged on the substrate 100 between the terminal 11 for transmitting or receiving and the upper end of the core conductor 300, and they are connected to each other at the electromagnetic wave level. The lower end of the core conductor 300 contacts the upper end of a lower feed conductor 303 extending below the substrate 100, and the lower end of the lower feed conductor 303 contacts or is high-frequency coupled to the conductive upper surface of the ridge 201. The inventions corresponding to the claims of this specification are the inventions described in FIGS. 14A to 14F, which are subordinate inventions of the above basic invention. [First embodiment] 〔composition〕

[0023] Next, a first embodiment of the present invention will be described. FIGS. 1 to 4C are diagrams illustrating the first embodiment. FIG. 1 is a perspective view illustrating a schematic configuration example of a waveguide device 1 according to the first embodiment. FIG. 2 is a cross-sectional view taken along line A-A' in FIG. 1. In FIG. 2, wiring and other components formed on a substrate are partially shown floating in the air to clearly show the connection configuration. The waveguide device of the present invention can be used not only for transmitting and receiving high-frequency signals, but also for applications that do not use radio waves as signals, such as chemical reaction channels and power transmission. As shown in FIGS. 1 and 2, the waveguide device 1 includes an IC mounting substrate 2, multiple first waveguides 3, a WRG (Waffle Iron Ridge Wave Guide) structure 4, and multiple second waveguides 5, the number of which corresponds to the number of the first waveguides 3. The IC mounting substrate 2 includes a substrate 100 having an upper surface and a lower surface, a millimeter-wave IC 10 (hereinafter referred to as "MMIC 10") disposed (mounted) on the upper surface of the substrate 100, and a first member 102 disposed on the lower surface of the substrate 100.

[0024] Here, the term "top surface" refers to the collection of surfaces (including a single surface) that includes all surfaces included in the field of view when viewing an object such as substrate 100 from a far point above the Z axis, with the +Z direction of the Z axis in Figures 1 and 2 defined as up and the -Z direction as down. Similarly, the term "bottom surface" refers to the collection of surfaces that includes all surfaces included in the field of view when viewing an object from below the Z axis. In other words, even for objects with complex shapes with multiple surfaces, such as stepped shapes, the collection of these multiple surfaces is the top or bottom surface. Furthermore, whether or not the bottoms of recesses or holes present on the surface of each surface are included in the top and bottom surfaces is defined on a case-by-case basis. Furthermore, even if the object is flipped 180 degrees and the top surface defined in Figures 1 and 2 faces downward (in the -Z direction), it is still considered the top surface. Similarly, even if the bottom surface faces upward (in the +Z direction), it is still considered the bottom surface. The same applies to objects facing in other directions. Furthermore, "top side" refers to the upward direction, including the top surface. Similarly, "bottom side" refers to the downward direction, including the bottom surface.

[0025] 1 and 2, the +X direction is the forward direction, the −X direction is the rearward direction, the +Y direction is the leftward direction, and the −Y direction is the rightward direction. This also applies to subsequent figures from the same perspective. The IC mounting board 2 further includes a ground pattern 101 provided on the upper surface of the substrate 100. Here, the substrate 100 may be formed of, for example, a dielectric substrate. The substrate 100 is not limited to a flat plate, but may have a complex shape such as a 3D shape. In this case, a wiring pattern or the like can be formed using, for example, MID (Molded Interconnect Device) technology. The first member 102 can be formed of a ground pattern provided on the lower surface of the substrate 100, a thin conductive plate (e.g., a metal plate) separate from the substrate 100, or a thin plate of a dielectric material separate from the substrate 100 with a conductive surface formed on at least the lower surface thereof. In the first embodiment, the first member 102 is formed of a ground pattern provided on the lower surface of the substrate 100.

[0026] The MMIC 10 has a large number of terminals. The large number of terminals are arranged, for example, on the bottom surface of the MMIC 10. The large number of terminals include a plurality of pairs of transmitting / receiving terminals 11 for transmitting or receiving high-frequency electromagnetic waves and signal ground terminals 12. In addition, the large number of terminals may include, for example, one or more of an antenna input / output terminal, a power supply terminal, a control terminal, and a shield ground terminal. The MMIC 10 of the first embodiment is configured, for example, in a BGA package, and the large number of terminals are configured as solder ball-type terminals.

[0027] The first waveguide 3 includes a core conductor 300 formed adjacent to the MMIC 10 in a top view, for example, at a position adjacent to the outside of the outline of the MMIC 10, penetrating the substrate 100 and the first member 102 in the vertical direction, and a peripheral conductor 103 formed around the core conductor 300, penetrating the substrate 100 in the vertical direction. Here, "around" refers to a distance within which the core conductor 300 and the peripheral conductor 103 can form a waveguide equivalent to a coaxial waveguide or a triplate strip waveguide. The core conductor 300 and the peripheral conductor 103 are made of a conductor such as copper.

[0028] As an example, the first waveguide 3 of the first embodiment includes a core conductor 300 that is generally circular in top view and six peripheral conductors 103 that are generally circular in top view and arranged around the core conductor 300 along a circle concentric with the core conductor 300. Note that the configuration of the first waveguide 3 is not limited to this. Other configuration examples will be described separately in modified examples. The core conductor 300 can be configured, for example, by embedding a conductor in a through-hole provided in the substrate 100 or by inserting a separate conductor. An upper end 301 of the core conductor 300 is connected to the transmitting / receiving terminal 11 via a feed waveguide 302 provided on the upper surface of the substrate 100. Specifically, one end of the feed waveguide 302 is connected to the transmitting / receiving terminal 11, and the other end is connected to the upper end 301 of the core conductor 300.

[0029] The feed waveguide 302 is composed of a microstrip line formed by a transmission line made of a conductor formed on the upper surface of the substrate 100 and a first member 102 located on the lower surface of the transmission line, sandwiching the substrate 100. That is, a high-frequency electromagnetic field propagates between the transmission line and the first member 102 constituting the ground conductor. Note that although a BGA package is used as an example of the package of the MMIC 10, the configuration of the first embodiment in which connection is made via the feed waveguide 302 can flexibly accommodate not only BGA packages but also other terminal-type packages.

[0030] 3(a) is a top view of the WRG structure 4, FIG. 3(b) is a partial perspective view of the WRG structure 4, and FIG. 3(c) is a partial cross-sectional view taken along line B-B' in FIG. 3(a). As shown in FIGS. 1, 2, and 3(a) to 3(c), the WRG structure 4 includes a second member 200, a plurality of ridges 201 provided on the upper surface of the second member 200, a plurality of rods 202 having conductive surfaces provided adjacent to both sides of each ridge 201, and openings 203 penetrating the second member 200 to the rear surface. The second member 200 has a conductive upper surface 200S, which is a conductive surface formed at least on the upper surface.

[0031] The ridges 201 extend opposite the conductive lower surface 102S, which is the conductive surface on the lower surface of the first member 102, and have a waveguide surface 201S consisting of a strip-shaped conductive upper surface. A plurality of rods 202 are arranged adjacent to at least both sides of each ridge 201, forming an electromagnetic wave shielding wall 210. The electromagnetic wave shielding wall 210 formed by the plurality of conductive rods 202 becomes an artificial magnetic wall. The plurality of rods 202 forming the artificial magnetic wall are called an artificial magnetic conductor. The waffle iron structure of the WRG structure 4 will be described in detail later, so only an overview will be given here.

[0032] In the first embodiment, leakage of a high-frequency electromagnetic field is suppressed by the confinement effect of the electromagnetic wave shielding wall 210 formed by the artificial magnetic conductor. As a result, a second waveguide 5 is formed by the opposing conductive lower surface 102S of the first member 102 and the conductive waveguide surface 201S of the ridge 201, and the high-frequency electromagnetic field is propagated via the second waveguide 5. The multiple rods 202 extend upward from the second member 200. In the examples of FIGS. 3(a) to (c), the multiple rods 202 have approximately the same length (height).

[0033] The conductive lower surface 102S of the first member 102 extends two-dimensionally along a plane (a plane parallel to the XY plane) perpendicular to the axial direction (Z direction) of the rod 202. It is recommended that this range be at least in the region facing the ridge 201 and the rod 202. In the first embodiment, the conductive lower surface 102S is a smooth plane, but the conductive lower surface 102S does not necessarily have to be a smooth plane. Here, in the first embodiment, the space between the conductive lower surface 102S of the first member 102 and the conductive upper surface 200S of the WRG structure 4 is filled with air. Note that the space may be filled with gas, vacuum, or the like, instead of air, or at least a portion of the space may be filled with a dielectric.

[0034] The opening 203 is a hole that penetrates the ridge 201 and the second member 200 from top to bottom, and serves as a waveguide that propagates electromagnetic waves to an antenna radiating element or the like, or as an antenna radiation hole. When the opening 203 is used as an antenna radiation hole, the waveguide device of the present invention can function as a radar device. Note that the arrangements of the ridges, rods, openings, walls, etc. in the drawings in this specification, such as Figures 2 and 3, are illustrative drawings intended only to explain the various components in the waveguide device of the present invention, and are not based on an arrangement intended to achieve a specific function unless explicitly stated.

[0035] 2, the IC mounting substrate 2 and the WRG structure 4 are arranged such that the core conductor 300 of the first waveguide 3 faces the upper waveguide surface 201S adjacent to the front end of the ridge 201. In the example of FIG. 2, the tip of the core conductor 300 is in contact with the waveguide surface 201S. That is, the lower end of the core conductor 300 serves as a feed conductor that feeds electromagnetic waves propagating through the first waveguide 3 to the second waveguide 5. Specifically, the core portion of the core conductor 300 (i.e., the core of the substrate portion) and its lower half serving as a feed conductor (i.e., the portion from the lower end of the substrate to the waveguide surface 201S) (hereinafter referred to as the "lower feed conductor") are continuously formed of the same material. That is, the core conductor 300 according to the first embodiment is made of a core extension conductor, and the lower feed conductor is made of an extended portion of the core. The core wire of the substrate portion and the lower power supply conductor may be made of different conductive materials.

[0036] The contact between the lower feed conductor of the core conductor 300 and the waveguide surface 201S can be fixed by soldering, a conductive adhesive, or the like, although not shown. In the present invention, "contact" refers to a state in which two components having conductive surfaces are physically abutted and fixed with screws or the like, two components having conductive surfaces are integrally formed, or two components having conductive surfaces are in contact with each other via a conductive material (including a conductive fixture such as a metal, a conductive adhesive, or a conductive oil), and are electrically conductive to each other. The term "contact" may also be used to refer to not only direct contact but also indirect conduction via another conductor. The propagation of electromagnetic waves between the first waveguide 3 and the second waveguide 5 does not necessarily require the lower feed conductor to be in contact with the waveguide surface 201S. Specifically, the lower feed conductor and the waveguide surface 201S may be high-frequency coupled without contact. The high-frequency coupling configuration will be described in detail in the sixth modification and the third embodiment.

[0037] Here, the first waveguide 3 is configured to have a function equivalent to a coaxial waveguide or a triplate strip waveguide, and propagates electromagnetic waves fed from the MMIC 10 via the feed waveguide 302. The same applies to electromagnetic waves fed from the second waveguide 5 to the first waveguide 3. High-frequency coupling refers to the phenomenon in which capacitive coupling occurs between the lower feed conductor and the waveguide surface 201S because they are close to each other but not in contact with each other, and coupling occurs in the high-frequency region in the frequency band used (for example, a frequency of around 80 GHz in the case of millimeter-wave radar), resulting in an electrically conductive state. [Connection configuration example]

[0038] Next, a specific example of the connection configuration of each component in the IC mounting substrate 2, including the first waveguides 3, the terminal sets of the MMIC 10, the feed waveguides 302, and the first member 102, will be described. FIG. 4A is a diagram showing a first example of the connection configuration of each component in the IC mounting substrate 2, and is a partial top view of the IC mounting substrate 2 as viewed from the top surface. FIG. 4B is a diagram showing the first example of the connection configuration of each component in the IC mounting substrate 2, and is a partial bottom view of the IC mounting substrate 2 as viewed from the bottom surface. FIG. 4C(a) is a diagram showing the structure of a microstrip line, FIG. 4C(b) is a diagram showing the structure of a coplanar line, and FIG. 4C(c) is a diagram showing the structure of a post-wall waveguide.

[0039] As shown in FIGS. 4A and 4B, a plurality of first waveguides 3 are provided in the IC mounting substrate 2, penetrating the substrate 100 and the first member 102. For ease of explanation, the examples shown in FIGS. 4A and 4B show three first waveguides 3, but in reality, many more first waveguides 3 are provided. The upper end 301 of the core conductor 300 of each first waveguide 3 is electromagnetically connected to each transmitting / receiving terminal 11, which is a BGA terminal of the MMIC 10, by each feeding waveguide 302 formed by a microstrip line. Here, the feeding waveguide 302 corresponds to the upper feeding part 302 in FIG. 5 described above. As shown in FIG. 4C(a), the microstrip line is formed by a wiring pattern 302L provided on the upper surface of the substrate 100 and a first member 102 provided on the lower surface of the substrate 100, with the substrate 100 sandwiched therebetween.

[0040] 4A and 4B, each signal ground terminal 12 (hereinafter referred to as "SG terminal 12") of the MMIC 10 is connected to the first member 102 via a peripheral conductor 103 of the first waveguide 3 or a through-hole 104 provided in the substrate 100. In addition, the lower end of the peripheral conductor 103 of each first waveguide 3 is connected to the first member 102. Some of the peripheral conductors 103 are also connected to the ground pattern 101, which is connected to the first member 102 via a through via hole 111. That is, the peripheral conductors 103 and the SG terminal 12 are connected to the first member 102 and have the potential (ground potential) of the first member 102. On the other hand, the core conductor 300 has the potential of the electromagnetic wave supplied from the MMIC 10 via the transmitting / receiving terminal 11 or the electromagnetic wave supplied from the second waveguide 5 to the first waveguide 3. This allows electromagnetic waves to propagate between the core conductor 300 and the peripheral conductor 103 in the first waveguide 3. Note that to prevent a short circuit between the core conductor 300 and the first member 102, an area where no ground pattern (first member 102) is formed is provided around the core conductor 300 on the underside of the substrate 100. In the first embodiment, when forming the ground pattern that becomes the first member 102 on the underside of the substrate 100, an area is formed in accordance with the position of each core conductor 300.

[0041] The feed waveguide 302 is not limited to a microstrip line structure, and may be a coplanar line as shown in FIG. 4C(b) or a post-wall waveguide as shown in FIG. 4C(c). When the feed waveguide 302 is a coplanar line, it is composed of a wiring pattern 302L provided on the upper surface of the substrate 100 and ground patterns 101 provided on both sides of the wiring pattern 302L on the upper surface of the substrate 100. When the feed waveguide 302 is a post-wall waveguide, it is composed of the ground pattern 101 and the first member 102 arranged opposite each other across the substrate 100, and two rows of post walls between them, each row including a plurality of through holes 104 arranged in parallel and penetrating the substrate 100 from top to bottom. Each through hole 104 is electrically connected to the ground pattern 101 on the upper surface of the substrate 100 and to the first member 102 on the lower surface of the substrate 100. With this configuration, electromagnetic waves propagate between the ground pattern 101 and the first member 102 and between the two rows of post walls. [Effects of the first embodiment]

[0042] As described above, the waveguide device 1 of the first embodiment includes the substrate 100 having an upper surface and a lower surface, the MMIC 10 arranged on the upper surface side of the substrate 100 and having a set of terminal 11 and SG terminal 12 for transmitting or receiving, the first member 102 arranged along the lower surface side of the substrate 100 and having a conductive lower surface 102S that is electrically connected to the SG terminal 12 of the MMIC 10, the core conductor 300 that passes through the substrate 100 and the first member 102 in the vertical direction, and the peripheral conductor 103 that is arranged around the core conductor 300 along the core conductor 300 with an insulator (dielectric of the substrate 100) interposed therebetween and that is in contact with the conductive lower surface 102S of the first member 102, the first waveguide 3 including the second member 200 arranged along the lower surface side of the first member 102 and having a conductive upper surface, and the first member 102 and the second member 200. 200, and having a waveguide surface 201S which is a strip-shaped conductive upper surface facing the conductive lower surface 102S of the first member 102; a second waveguide 5 constituted by the waveguide surface 201S of the ridge 201 and the conductive lower surface 102S of the first member 102; an electromagnetic wave blocking wall 210 (comprised of a plurality of rods 202) disposed between the first member 102 and the second member 200 and disposed adjacent to the second waveguide 5; a feed waveguide 302 disposed on the upper surface of the substrate 100, and electromagnetically connecting the transmitting / receiving terminal 11 of the MMIC 10 and the end of the core conductor 300 on the upper surface side of the substrate; and a lower feed conductor (composed of the lower end of the core conductor 300) which contacts or high-frequency couples the end of the core conductor 300 on the lower surface side of the first member 102 to one end of the second waveguide 5 disposed below said end. In the waveguide device 1 of the first embodiment, the SG terminal 12 of the MMIC 10 is connected to the conductive lower surface 102S of the first member 102 via the peripheral conductor 103 or the through-hole 104.

[0043] With the configuration described above, the installation space required for the first waveguide 3 on the substrate 100 can be reduced compared to a conventional configuration in which a rectangular waveguide or the like is formed on a substrate. Specifically, the installation space can be reduced to ½ or less of the free space wavelength λo of the highest frequency of the electromagnetic wave (millimeter wave) propagating through the first waveguide 3. This makes it possible to provide a waveguide device that can connect the transmitting / receiving terminal 11 of a millimeter wave IC (MMIC) and an antenna radiating element in a simple, space-saving, inexpensive, and efficient manner, even when there are a large number of transmitting and receiving channels.

[0044] Furthermore, since the degree of freedom in installation is high and the first waveguide 3 can be formed near the MMIC 10, the distance between the transmitting / receiving terminal 11 and the first waveguide 3 can be shortened compared to conventional cases. This significantly reduces the transmission loss of electromagnetic waves. Furthermore, unlike the conventional rectangular waveguide configuration, the first waveguide 3 is a transmission line type power supply system (non-resonant type), which enables wideband power supply. Furthermore, the configuration of the first waveguide 3 can be configured to have a function equivalent to that of a coaxial waveguide or a triplate strip waveguide, which reduces the loss (dielectric loss angle tanδ) due to the material (dielectric) of the substrate 100. As a result, the transmission loss due to the substrate material can be reduced.

[0045] Furthermore, since the feed path between the transmitting / receiving terminal 11 and the first waveguide 3 is formed by the feed waveguide 302 made of a microstrip waveguide, the position at which the first waveguide 3 is formed can be designed relatively freely. For example, the first waveguide 3 can be formed at a position that matches the arrangement interval of the ridges 201 of the WRG structure 4. This allows the end of the core conductor 300 on the lower surface side of the first member 102 to be in contact with or high-frequency coupled to one end of the second waveguide 5 without bending the ridge 201 side, thereby preventing the WRG structure 4 from becoming complicated and large. Second Embodiment 〔composition〕

[0046] Next, a second embodiment of the present invention will be described. Figures 6 and 7 are diagrams illustrating the second embodiment. Figure 6 is a perspective view showing a schematic configuration example of a waveguide device 1A according to the second embodiment. Figure 7 is a partial cross-sectional view taken along line A-A' in Figure 6. The second embodiment differs from the first embodiment in that the transmitting / receiving terminal 11 and the SG terminal 12 of the MMIC 10 are connected to the upper ends of the core conductor 300 and the peripheral conductor 103 in a contacting state via connection conductors. Hereinafter, this connection configuration will be referred to as a "direct connection configuration."

[0047] 6 and 7, a waveguide device 1A according to the second embodiment includes an IC mounting substrate 2A instead of the IC mounting substrate 2 and a first waveguide 3A instead of the first waveguide 3 in the waveguide device 1 according to the first embodiment. The IC mounting substrate 2A has a plurality of first waveguides 3A penetrating a substrate 100, and an MMIC 10 is mounted on the upper surface of the substrate 100 so as to cover the plurality of first waveguides 3A from above.

[0048] In the second embodiment, the MMIC 10 has terminals arranged in a grid pattern on the underside of a package such as a BGA package. In the second embodiment, a BGA package is used as an example. The upper ends of the core conductors 300 of the multiple first waveguides 3A are located at positions corresponding to the mounting positions of the transmitting and receiving terminals 11 of the MMIC 10 on the substrate 100. In addition, the upper ends of the peripheral conductors 103 are located at positions corresponding to the mounting positions of the SG terminals 12 of the MMIC 10 on the substrate 100.

[0049] That is, the MMIC 10 is arranged so that each transmitting / receiving terminal 11 and each SG terminal 12 overlaps the upper end of the core conductor 300 and peripheral conductor 103 of each first waveguide 3A. Note that it may be difficult to arrange all of the SG terminals 12 at positions that overlap the upper end of the peripheral conductor 103, depending on the configuration and number of the peripheral conductors 103. Therefore, a configuration may be adopted in which the SG terminals 12 are connected to each other by a wiring pattern on the substrate 100 or the like, so that they can be connected to the peripheral conductor 103 even if they do not overlap. In the second embodiment, each transmitting / receiving terminal 11 and each SG terminal 12 are connected in contact with the upper end of the core conductor 300 and peripheral conductor 103 by a connecting conductor such as solder. Hereinafter, this connection configuration may be referred to as a "direct connection configuration."

[0050] The MMIC 10 employs a BGA package, with each terminal being a solder ball. Therefore, the transmit / receive terminals 11 can be directly connected to the upper ends of the core conductors 300 by reflow soldering using these solder balls as connecting conductors. Similarly, the SG terminals 12 can be directly connected to the upper ends of the peripheral conductors 103 by reflow soldering. Note that as long as the upper ends of the core conductors 300 and peripheral conductors 103 can be positioned at the mounting locations of the transmit / receive terminals 11 and SG terminals 12 of the MMIC 10, packages with other terminal shapes, such as lead and pad types, can be used. However, a grid-like arrangement of terminals on the underside of an IC package, such as a BGA or PGA, allows for a compact configuration of the MMIC 10 itself, which is effective in preventing the device from becoming larger due to the larger ICs used in multi-channel applications. BGAs are available with a variety of terminal center distances, such as 0.65 mm, 0.8 mm, and 1.0 mm. In order to prevent the device from becoming larger, it is effective to use one with as short a center-to-center distance as possible, but it is necessary to design the diameter of the core conductor 300 to match this center-to-center distance and to configure the position so that the core conductor 300 and the peripheral conductor 103 are not connected to the transmitting / receiving terminal 11 at the same time. [Effects of the second embodiment]

[0051] As described above, the waveguide device 1A of the second embodiment includes a first waveguide 3A including: a substrate 100 having an upper surface and a lower surface; an MMIC 10 disposed on the upper surface side of the substrate 100 and having a set of a transmitting / receiving terminal 11 and an SG terminal 12 for transmitting or receiving; a first member 102 disposed along the lower surface side of the substrate 100 and having a conductive lower surface 102S that is electrically connected to the SG terminal 12 of the MMIC 10; a core conductor 300 that passes through the substrate 100 and the first member 102 in the vertical direction; a peripheral conductor 103 that is disposed around the core conductor 300 along the core conductor 300 with an insulator (dielectric of the substrate 100) interposed therebetween and in contact with the conductive lower surface 102S of the first member 102; a second member 200 disposed along the lower surface side of the first member 102 and having a conductive upper surface; and a second member 200 disposed between the first member 102 and the second member 200 and having a conductive upper surface. the ridge 201 having a waveguide surface 201S which is a strip-shaped conductive upper surface facing the conductive lower surface 102S; a second waveguide 5 constituted by the waveguide surface 201S of the ridge 201 and the conductive lower surface 102S of the first member 102; an electromagnetic wave shielding wall 210 (comprised of a plurality of rods 202) disposed between the first member 102 and the second member 200 and disposed adjacent to the second waveguide 5; a connecting conductor (composed of a solder ball of the BGA terminal corresponding to the transmitting / receiving terminal 11 and corresponding to the upper feeding part 302 in FIG. 5 ) which fixes the transmitting / receiving terminal 11 of the MMIC 10 and the end of the core conductor 300 on the upper surface of the substrate 100 in a state of contact with each other on the upper surface of the substrate 100; and a lower feeding conductor (composed of the lower end of the core conductor 300) which contacts or high-frequency couples the end of the core conductor 300 on the lower surface of the first member 102 with one end of the second waveguide 5 disposed below the end. In the waveguide device 1A of the second embodiment, the SG terminal 12 of the MMIC 10 is connected to the conductive lower surface 102S of the first member 102 via the peripheral conductor 103.

[0052] In addition to the effects of the first embodiment, the configuration described above makes it possible to significantly reduce the transmission loss of electromagnetic waves by directly connecting the transmitting / receiving terminal 11 and the first waveguide 3. Furthermore, it is possible to significantly reduce the space required to connect the transmitting / receiving terminal 11 and the first waveguide 3, making it possible to further miniaturize the device. [Modifications of the first and second embodiments]

[0053] Next, modifications of the first and second embodiments will be described. Fig. 8 is a drawing showing this modification. Figs. 8(a) to 8(h) are top views showing structural examples of the first waveguide 3 according to modifications 1 to 8. Note that the structural examples shown in Figs. 8(a) to 8(h) are structural examples common to the first waveguide 3 and 3A, and therefore will be described below as structural examples of the first waveguide 3 without distinguishing between them. That is, the core conductor 300 and the peripheral conductor 103 of the first waveguide 3 according to the first and second embodiments can have any of the structures shown in Figs. 8(a) to 8(h). [Variation 1]

[0054] First, a first modification of the first waveguide 3 shown in Fig. 8(a) will be described. The first waveguide 3 according to the first modification is provided so as to penetrate the substrate 100 and the first member 102 in the vertical direction. The same applies to the structural examples of Figs. 8(b) to (h), and therefore the description will be omitted as appropriate.

[0055] As shown in FIG. 8( a), the first waveguide 3 according to the first modification includes a core conductor 300 that is elliptical in top view and one peripheral conductor 103 that is rectangular in top view and adjacent to the core conductor 300 with a predetermined gap therebetween. The peripheral conductor 103 is connected to a first member 102. That is, the first waveguide 3 according to the first modification includes an elliptical cylindrical core conductor 300 and one plate-like peripheral conductor 103 that is adjacent to the core conductor 300 with a predetermined gap therebetween, with the dielectric of the substrate 100 sandwiched between them. In the example shown in FIG. 8( a), the core conductor 300 is elliptical with its major axis in the Y direction and its minor axis in the X direction, and the peripheral conductor 103 is rectangular with its long side in the Y direction and its short side in the X direction. The peripheral conductor 103 is adjacent to the core conductor 300 on the −X direction side. Although the core conductor 300 may be circular in top view, an elliptical shape increases the area facing the peripheral conductor 103, resulting in higher transmission efficiency. The predetermined interval is designed to be an appropriate interval depending on factors such as impedance matching with the second waveguide 5. This also applies to the structural examples of Figures 8(b) to 8(h). With this configuration, electromagnetic waves can be propagated between the elliptical cylindrical core conductor 300 and one plate-like peripheral conductor 103. [Variation 2]

[0056] Next, a second modification of the first waveguide 3 shown in Fig. 8(b) will be described. As shown in Fig. 8(b), the first waveguide 3 according to this modification 1-2 has a configuration similar to that of the first modification, except that a peripheral conductor 103 having the same shape as that of the first modification is arranged adjacent to the core conductor 300 on the +X-direction side. That is, the core conductor 300 is sandwiched between the two peripheral conductors 103 on both sides in the X-direction. With this configuration, the first waveguide 3 can propagate electromagnetic waves between the elliptical cylindrical core conductor 300 and the two plate-like peripheral conductors 103. [Variation 3]

[0057] Next, Modification 3 of the first waveguide 3 shown in Fig. 8(c) will be described. As shown in Fig. 8(c), the first waveguide 3 according to Modification 3 has a configuration similar to Modification 1-2, except that peripheral conductors 103 having the shape of Modification 1 are arranged adjacent to the core conductor 300 on both sides in the +Y direction and the -Y direction, rotated by 90° around the Z axis. That is, the core conductor 300 is sandwiched between four peripheral conductors 103 on both sides in the X direction and on both sides in the Y direction. With this configuration, the first waveguide 3 can propagate electromagnetic waves between the elliptical cylindrical core conductor 300 and the four plate-like peripheral conductors 103. [Variation 4]

[0058] Next, a fourth modification of the first waveguide 3 shown in FIG. 8(d) will be described. The first waveguide 3 according to this fourth modification has a structure similar to that of the first waveguides 3 and 3A according to the first and second embodiments. Specifically, the first waveguide 3 according to this fourth modification includes a core conductor 300 that is elliptical in top view and six peripheral conductors 103 that are circular in top view and arranged concentrically around the core conductor 300. The six peripheral conductors 103 are arranged in opposing positions in the X direction, with three on the −X-direction side of the core conductor 300 and three on the +X-direction side. With this configuration, the first waveguide 3 can propagate electromagnetic waves between the elliptical cylindrical core conductor 300 and the six circular cylindrical peripheral conductors 103. Note that the core conductor 300 may also be circular in top view. [Variation 5]

[0059] Next, a fifth modification of the first waveguide 3 shown in Fig. 8(e) will be described. As shown in Fig. 8(e), the first waveguide 3 according to this fifth modification has a configuration in which the number of peripheral conductors 103 in the fourth modification is increased from six to ten. With this configuration, the first waveguide 3 forms a waveguide closer to a coaxial waveguide, and electromagnetic waves can propagate between the elliptical cylindrical core conductor 300 and the ten circular cylindrical peripheral conductors 103. Note that the core conductor 300 may have a circular shape when viewed from above. [Variation 6]

[0060] Next, a sixth modification of the first waveguide 3 shown in Fig. 8(f) will be described. As shown in Fig. 8(f), the first waveguide 3 according to this sixth modification has the same structure as the fourth modification except that the three peripheral conductors 103 on the +X direction side are different from the first waveguide 3 according to the fourth modification. of With this configuration, the first waveguide 3 can propagate electromagnetic waves between the elliptic cylindrical core conductor 300 and the three circular cylindrical peripheral conductors 103. The core conductor 300 may have a circular shape when viewed from above. [Variation 7]

[0061] Next, a seventh modification of the first waveguide 3 shown in FIG. 8(g) will be described. As shown in FIG. 8(g), the first waveguide 3 according to this seventh modification has a configuration in which the core conductor 300 in the first modification is rectangular in top view. That is, the core conductor 300 is configured in a plate shape. In the example shown in FIG. 8(g), the thickness of the core conductor 300 is greater than the thickness of the peripheral conductor 103. This configuration allows electromagnetic waves to propagate between the plate-shaped core conductor 300 and one plate-shaped peripheral conductor 103. By making the core conductor 300 plate-shaped, the opposing area with the peripheral conductor 103 can be increased, thereby improving transmission efficiency. The configuration in which the core conductor 300 is plate-shaped can also be applied to other configurations such as FIG. 8(b). [Variation 8]

[0062] Next, an eighth modification of the first waveguide 3 shown in Fig. 8(h) will be described. As shown in Fig. 8(h), the first waveguide 3 according to this eighth modification has a core conductor 300 having an elliptical shape in top view, which is arranged in the center of a through hole having an elliptical shape in top view, and a peripheral conductor 103 having an elliptical cylindrical shape, which is arranged on the inner periphery of the through hole. A space filled with air (insulator) is formed between the core conductor 300 and the peripheral conductor 103, and a coaxial waveguide can be formed. Note that the through hole and the core conductor 300 may also have a perfect circular shape in top view.

[0063] The structure of the first waveguide 3 is not limited to the structures of the above-described Modifications 1 to 8. For example, in the structure of FIG. 8(c), one of the four rectangular peripheral conductors 103 facing in the X direction or the Y direction may be configured as a peripheral conductor 103 that is, for example, circular or elliptical in top view, thereby forming a structure in which a plurality of types of conductor shapes are combined. Although FIGS. 9 to 13 illustrate a configuration in which the configuration of Modification 6 is applied to the waveguide device 1 of the first embodiment, Modification 6 is applicable to both the waveguide devices 1 and 1A of the above-described first and second embodiments. Below, a case in which it is applied to the waveguide device 1 will be described as a representative example. [Another Modification 1 of the First and Second Embodiments]

[0064] Next, another modified example 1 of the first and second embodiments will be described. FIGS. 9 to 12 are diagrams illustrating another modified example 1 of the first and second embodiments. In the waveguide device 1 according to this modified example 1, as shown in FIGS. 9(a) and 9(b), the upper end of a core conductor 310 is inserted into through-holes provided in the substrate 100 and the first member 102, and the lower end is inserted into a through-hole 204B provided in the WRG structure 4A in a non-contact manner while maintaining high-frequency coupling. Specifically, as shown in FIG. 10(a), the core conductor 310 according to this modified example 1 has a cylindrical upper portion 310a with a height h1 and a cylindrical lower portion 310b with a height h2 that is larger in diameter and longer than the diameter of the upper portion 310a. The upper portion 310a and the lower portion 310b are concentrically arranged. To give a specific example of numerical values, the height h1 and diameter φa of the upper portion 310a can be, for example, 0.23 mm and 0.25 mm. In this case, the height h2 and diameter φb of the lower portion 310b may be, for example, 0.70 mm and 0.40 mm.

[0065] As shown in FIGS. 9(b) and 11, the WRG structure 4A according to Modification 1 has a through-hole 204B that vertically penetrates the ridge 201 and the second member 200 at a position on the waveguide surface 201S facing the lower end of the core conductor 310 at one end on the front side of the ridge 201. To give a specific example of numerical values, the diameter φc of the through-hole 204B can be, for example, 0.45 mm, corresponding to the above-mentioned numerical example. Furthermore, a thick portion 201t that protrudes upward and has a rectangular shape in a top view is provided on the waveguide surface 201S adjacent to the rear side of the through-hole 204B of the ridge 201. This thick portion 201t forms a step on the waveguide surface 201S of the ridge 201. The thick portion 201t is provided to achieve a matching (impedance matching) state without reflection of electromagnetic waves at the connection portion between the first waveguide 3 and the second waveguide 5. 10(b), 10(c) and 11, the upper portion 310a of the core conductor 310 is inserted into a through-hole formed in the substrate 100, and the upper end of the upper portion 310a, although not shown, is connected to the other end of the feed waveguide 302 by soldering, a conductive adhesive, or the like. In the case of a direct coupling configuration, it is directly connected to the transmitting / receiving terminal 11 of the MMIC 10.

[0066] Meanwhile, a portion of the lower portion 310b of the core conductor 310 is inserted from above into the portion of the through hole 204B on the ridge 201 side. At this time, the outer periphery of the inserted portion of the lower portion 310b is out of contact with the inner periphery of the through hole 204B and maintains a high-frequency coupled state. Specifically, the out-of-contact state occurs near the point where the difference between the outer diameter of the lower portion 310b and the inner diameter of the through hole 204B is approximately 0.5 mm. That is, there is a gap of 0.025 mm between the outer periphery of the lower portion 310b and the inner periphery of the through hole 204B. Furthermore, the portion of the through hole 204B below the lower portion 310b of the core conductor 310 is hollow.

[0067] In another modification 1, the inner diameter of the through hole 204B is less than half the wavelength λ of the propagating electromagnetic wave (millimeter wave). This prevents the electromagnetic wave propagating from the first waveguide 3 from propagating below the lower portion 310b of the core conductor 310, thereby reducing transmission loss. Furthermore, the length h3 of the lower portion 310b of the core conductor 310 inserted into the through hole 204B can be set to a length that adjusts the connection between the first waveguide 3 and the second waveguide 5 to a matched state. As a result, as shown in FIGS. 12(a) to 12(d), it can be seen that the electromagnetic wave from the MMIC 10 propagates through the first waveguide 3 from above to below the substrate 100 with sufficient propagation efficiency. Additionally, it can be seen that the electromagnetic wave propagating from the first waveguide 3 propagates through the second waveguide 5 from one end to the other end of the ridge 201 with sufficient propagation efficiency. [Another Modification 2 of the First and Second Embodiments]

[0068] Next, another modified example 2 of the first and second embodiments will be described. Fig. 13A is a cross-sectional view showing a schematic configuration example of a waveguide device 1B according to another modified example 2. Note that Fig. 13A illustrates a configuration in which the configuration of another modified example 2 is applied to the waveguide device 1 of the first embodiment, but another modified example 2 is a configuration that can be applied to both the waveguide devices 1 and 1A of the first and second embodiments. Below, a case in which it is applied to the waveguide device 1 will be described as a representative example.

[0069] As shown in FIG. 13A , the waveguide device 1B has a configuration in which the WRG structure 4 in the waveguide device 1 of the first embodiment is replaced with a WRG structure 4C. The WRG structure 4C includes a rod-shaped conductor 202A provided on the conductive upper surface 200S of the second member 200, at a position forward beyond a ridge front end face 201a, which is the front end face of the ridge 201, and facing the ridge front end face 201a. Furthermore, the WRG structure 4C includes a rod-shaped conductor 202B provided on the conductive upper surface 200S of the second member 200, at a position rearward beyond a ridge rear end face 201b, which is the rear end face of the ridge 201, and facing the ridge rear end face 201b. Specifically, the rod-shaped conductor 202A is provided at a position facing the ridge rear end face 201b in the X direction, with the opening 203 sandwiched therebetween.

[0070] The rod-shaped conductors 202A and 202B are made of rod-shaped conductors and are configured so that their upper surfaces are positioned at the same height as the waveguide surface 201S of the ridge 201. In other words, the upper surfaces of the rod-shaped conductors 202A and 202B are adjacent to the waveguide surface 201S of the ridge 201. The rod-shaped conductors 202A and 202B may be made entirely of a conductor, or may be configured such that a conductive surface is provided on the surface of a rod-shaped dielectric, for example.

[0071] 13A, the number of rod-shaped conductors 202A and 202B on the front and rear sides of the ridge 201 is two, but this configuration is not limited thereto; one rod-shaped conductor on each side, or three or more rod-shaped conductors on each side may be provided. With this configuration, the rod-shaped conductors 202A and 202B form an artificial magnetic wall, which can prevent electromagnetic waves propagating through the first waveguide 3 from traveling from the front end of the ridge 201 into the space outside the front. In addition, it can prevent electromagnetic waves propagating rearward through the second waveguide 5 from traveling beyond the opening 203 into the space beyond. In other words, the rod-shaped conductors 202A and 202B can restrict the path of the electromagnetic waves so that they propagate along a desired path. [Another Modification 3 of the First and Second Embodiments]

[0072] Next, another modified example 3 of the first and second embodiments will be described. Fig. 13B is a cross-sectional view showing a schematic configuration example of a waveguide device 1C according to another modified example 3. Note that Fig. 13B illustrates a configuration in which the configuration of another modified example 3 is applied to the waveguide device 1 of the first embodiment, but another modified example 3 is applicable to both the waveguide devices 1 and 1A of the first and second embodiments. Below, a case in which it is applied to the waveguide device 1 will be described as a representative example.

[0073] As shown in FIG. 13B , the waveguide device 1C includes a WRG structure 4D instead of the WRG structure 4 of the waveguide device 1 of the first embodiment. The WRG structure 4D includes, in place of both the rod-shaped conductor 202A on the front side of the ridge 201 and the rod-shaped conductor 202B on the rear side, rod-shaped conductors 202C and 202D, respectively, which are extended to a height such that their upper ends contact the conductive lower surface 102S of the first member 102. In the example shown in FIG. 13B , there are two rod-shaped conductors 202C and two rod-shaped conductors 202D on the front side and the rear side of the ridge 201, respectively. However, this configuration is not limited thereto, and one rod-shaped conductor or three or more rod-shaped conductors may be provided on each side. With this configuration, the side surfaces of the rod-shaped conductors 202C and 202D facing the ridge front end surface 201a and the ridge rear end surface 201b form electric walls, respectively. This makes it possible to prevent electromagnetic waves propagating through the first waveguide 3 from traveling from the front end of the ridge 201 into the space outside the front. In addition, it is possible to prevent electromagnetic waves propagating rearward through the second waveguide 5 from traveling into the space beyond the opening 203. In other words, the rod-shaped conductors 202C and 202D on the front and rear sides of the ridge 201 can restrict the path of the electromagnetic waves so that they propagate along a desired path. [Alternative Modification 4 of the First and Second Embodiments] Next, a fourth modified example of the first and second embodiments will be described. Fig. 13C is a top view of a WRG structure 4E according to the fourth modified example. Fig. 13D is a cross-sectional view of a waveguide device 1D according to the fourth modified example taken along line A-A' in Fig. 13C.

[0074] 13C and 13D, the waveguide device 1D includes a WRG structure 4E instead of the WRG structure 4 in the waveguide device 1 of the first embodiment. The WRG structure 4E includes wall portions 202E and 202F, which are larger in width in the front-rear direction (X direction) and in width in the left-right direction (Y direction), instead of both the rod-shaped conductor 202C on the front side of the ridge 201 and the rod-shaped conductor 202D on the rear side of the ridge 201 in the WRG structure 4D of the third modified example.

[0075] In the example shown in FIGS. 13C and 13D, the width of the ridge 201 in the left-right direction is set to λo / 8. Here, λo is the free-space wavelength of the electromagnetic wave at the center frequency of the operating frequency band of the waveguide device 1D. Additionally, in the example shown in FIGS. 13C and 13D, the width of the walls 202E and 202F in the left-right direction is set to λo / 4 or more. This configuration allows the side surfaces of the walls 202E and 202F facing the ridge front end face 201a and the ridge rear end face 201b to form electric walls, respectively. This prevents electromagnetic waves propagating through the first waveguide 3 from traveling from the front end of the ridge 201 to the space outside the front. Additionally, it prevents electromagnetic waves propagating backward through the second waveguide 5 from traveling beyond the opening 203 to the space beyond. That is, the front and rear wall portions 202E and 202F of the ridge 201 can restrict the path of the electromagnetic waves so that they propagate along a desired path. Third Embodiment 〔composition〕

[0076] Next, a third embodiment of the present invention will be described. Figs. 14A to 14D are diagrams illustrating the third embodiment. Fig. 14A is a cross-sectional view showing a schematic configuration example of a waveguide device 1H according to the third embodiment. Fig. 14B is a partial perspective view showing a state in which a first waveguide 3C according to the third embodiment is high-frequency coupled to a second waveguide 5. Fig. 14C is a partial cross-sectional view taken along line A-A' in Fig. 14B. Fig. 14D is a diagram illustrating simulation results of the transmission characteristics and reflection characteristics of the waveguide device 1H configured as shown in Fig. 14A. In Fig. 14D, the horizontal axis represents frequency (GHz), and the vertical axis represents transmission loss and return loss (dB).

[0077] In the third embodiment, the side surface of the lower feed conductor 300Cc of the core conductor 300C of the first waveguide 3C is arranged opposite and close to the ridge front end face 201a, which is the end face on the front side (+X direction side, i.e., the direction in which the ridge extends) of the ridge 201, and the first waveguide 3C and the second waveguide 5 are in a high-frequency coupled state.

[0078] As shown in FIGS. 14A and 14B, a waveguide device 1H according to the third embodiment includes an IC mounting substrate 2, a first waveguide 3C, and a WRG structure 4F. The first waveguide 3C includes a core conductor 300C instead of the core conductor 300 in the first waveguide 3A of the second embodiment. The core conductor 300C includes a conductor portion 300Ca and a coating portion 300Cb on the portion of the conductor portion 300Ca that faces the substrate 100. The core conductor 300C has the same core extension conductor configuration as the core conductor 300 of the first embodiment, and a lower feed conductor 300Cc is integrated with the lower end of the conductor portion 300Ca. The lower feed conductor 300Cc is not coated with the coating portion 300Cb, and the conductor is exposed. The coating portion 300Cb is made of a dielectric material such as PTFE (polytetrafluoroethylene).

[0079] The core conductor 300C has a substrate-internal portion 300Ca and a portion 300Cc protruding downward from the substrate 100, the latter portion serving as the lower feed conductor. As shown in FIG. 14C , the lower feed conductor 300Cc is positioned facing the ridge front end face 201a with a predetermined distance between them. Specifically, the lower feed conductor 300Cc is positioned close to but not in contact with the ridge front end face 201a, thereby providing high-frequency coupling. The shaded space 206 in FIG. 14C is the space between the first member 102 and the second member 200, and is filled with air. A rod-shaped conductor 202G having a conductive surface is positioned facing the ridge front end face 201a in the +X direction (i.e., the direction in which the ridge 201 extends) across the lower feed conductor 300Cc. There is a gap between the top surface of this rod-shaped conductor 202G and the bottom surface of the first member 102, preventing electrical continuity. The rod-shaped conductor 202G seals the leakage of electromagnetic waves propagating between the first waveguide 3C and the second waveguide 5.

[0080] 14A , the distance between the lower feed conductor 300Cc of the core conductor 300C and the ridge front end face 201a may be, for example, 0.25 mm. The diameter of the conductor portion 300Ca of the core conductor 300C may be, for example, 0.29 mm. The diameter of the substantially cylindrical shape in which the peripheral conductor 103 is disposed may be, for example, 0.94 mm. With this configuration, the first waveguide 3C has a coaxial waveguide configuration, and the lower feed conductor 300Cc of the core conductor 300C and the ridge 201 are high-frequency coupled, allowing electromagnetic waves propagating through the first waveguide 3C to propagate through the second waveguide 5.

[0081] Next, we will explain the results of measuring the transmission loss and return loss of the first waveguide 3C and the second waveguide 5 using a circuit simulator in the configuration of the above numerical example. Here, the end of the second waveguide 5 opposite the ridge front end facet 201a is designated port 1, and the end of the first waveguide 3C on the upper surface side of the substrate 100 is designated port 2. Therefore, S12 is the ratio of the power of the electromagnetic wave input to port 2 to the power of the electromagnetic wave output from port 1. Furthermore, S22 is the ratio of the power of the electromagnetic wave input to port 2 to the power of the electromagnetic wave reflected by the load and returned. Note that in FIG. 14D, both S12 and S22 are converted to negative dB values ​​as transmission loss and return loss.

[0082] The solid line in FIG. 14D shows the simulation results of the transmission characteristics (passage loss), and the transmission loss at the target frequencies was as follows: S12 (passage loss) was −0.1020 dB at a frequency of 81 GHz, −0.1083 dB at a frequency of 76 GHz, and −0.1011 dB at a frequency of 79 GHz. The dashed line in FIG. 14D shows the simulation results of the reflection characteristics (return loss), and the return loss at the target frequencies was as follows: S22 (return loss) was −27.283 dB at a frequency of 81 GHz, −23.155 dB at a frequency of 76 GHz, and −25.528 dB at a frequency of 79 GHz. From the above simulation results, it can be seen that a waveguide connection with sufficiently low loss can be achieved in a high-frequency coupling state in which the lower feed conductor 300Cc of the core conductor 300C is brought close to, but not in contact with, the ridge front end face 201a, which is the front side surface of the ridge 201.

[0083] In the third embodiment, the lower power supply conductor 300Cc of the core conductor 300C is arranged at a predetermined distance from the ridge front end face 201a (in a non-contact, high-frequency coupled state), but this configuration is not limiting, and the lower power supply conductor 300Cc may also be arranged in contact with the ridge front end face 201a. [Modification of the third embodiment]

[0084] Next, Modifications 1 and 2 of the third embodiment will be described with reference to FIGS. 14E and 14F. First, Modification 1 of the third embodiment shown in FIG. 14E will be described. As shown in FIG. 14E, a waveguide device 1K according to Modification 1 includes a WRG structure 4G instead of the WRG structure 4F in the waveguide device 1H shown in FIG. 14A of the third embodiment. The WRG structure 4G includes a rod-shaped conductor 202H instead of the rod-shaped conductor 202G in the WRG structure 4F. The rod-shaped conductor 202H has a configuration in which its upper surface is in contact with the lower surface of the first member 102, thereby providing a conductive state, or is in close proximity but not in contact, thereby providing a high-frequency coupled state. Simulation results have confirmed that this configuration also prevents electromagnetic wave leakage, similar to the waveguide device 1H of FIG. 14A.

[0085] Furthermore, as shown in FIG. 14F, a waveguide device 1L according to Modification 2 of the third embodiment includes a WRG structure 4H instead of the WRG structure 4F of the waveguide device 1H shown in FIG. 14A. The WRG structure 4H includes a wall 202K instead of the rod-shaped conductor 202G of the WRG structure 4F. The wall 202K has a configuration in which its upper surface is in contact with the lower surface of the first member 102, thereby providing a conductive state, or in close proximity but not in contact, thereby providing a high-frequency coupled state. The width of the wall 202K in the +X direction (i.e., the direction in which the ridge 201 extends) and in the direction perpendicular to the height direction is equal to or greater than ¼ of the free-space wavelength λo of the electromagnetic wave at the center frequency of the operating frequency band. Simulation results have confirmed that this configuration can also seal against electromagnetic wave leakage, similar to the waveguide device 1H shown in FIG. 14A. [Another modification of the third embodiment]

[0086] Next, another modification of the third embodiment will be described with reference to Fig. 15. In this modification, as shown in Fig. 15, in the third embodiment and its modifications, a thick portion 201t is provided on the waveguide surface 201S of the ridge 201 so as to protrude upward and be adjacent to the front side of the lower feed conductor 300Cc of the core conductor 300C. In addition, thick portions 201st are provided on the left and right side surfaces of the ridge 201 so as to protrude left and right, respectively, so as to protrude left and right, in a top view. Furthermore, a forward convex portion 201ut is provided on the ridge front end surface 201a so as to protrude downward and be adjacent to the lower end of the lower feed conductor 300Cc.

[0087] With this configuration, a step (uneven portion) due to the thick portion 201t is formed on the top surface of the ridge 201 at a position close to the rear side of the lower feed conductor 300Cc of the core conductor 300. Furthermore, step (uneven portion) due to the thick portion 201st is formed on the side surface of the ridge 201 at positions close to the lower feed conductor 300Cc in both the left and right directions. Furthermore, step (uneven portion) due to the front convex portion 201ut is formed on the ridge front end face 201a of the ridge 201 at a position close to the lower side of the lower feed conductor 300Cc. As a result, the connection between the first waveguide 3C and the second waveguide 5 can be matched (impedance matched) by the thick portion 201t on the top surface, the thick portion 201st on the side surface, and the front convex portion 201ut on the ridge front end face 201a. In this modification, the rear surface of the lower feed conductor 300Cc may be in contact with the ridge front end surface 201a of the ridge 201. [Waffle iron structure]

[0088] Next, the waffle iron structure will be described with reference to Fig. 3(c). The rods 202 arranged on the second member 200 each have a tip 202a facing the conductive lower surface 102S. In the example shown in the figure, the tip 202a of the rods 202 are on the same plane. This plane forms the surface 202c of the artificial magnetic conductor.

[0089] Each rod 202 does not need to be entirely conductive; it is sufficient that a conductive layer extends along at least the top and side surfaces of the rod. This conductive layer may be located on the surface of the rod, or a resin layer may be provided on the surface for anti-rust coating or the like. Furthermore, the second member 200 does not need to be entirely conductive as long as an artificial magnetic conductor can be realized using multiple rods. Furthermore, it is sufficient that the surface of the region of the second member 200 where multiple rods are arranged is conductive, and that the surfaces of adjacent multiple rods are electrically conductive with the conductive top surface 200S of the second member.

[0090] The space between the surface 202c of each artificial magnetic conductor and the conductive lower surface 102S of the first member 102 does not allow electromagnetic waves having frequencies within a specific band to propagate. Such a frequency band is called a "forbidden band." The forbidden band can be adjusted by adjusting the height, width, and spacing of the rods 202, as well as the size of the gap between the rod tips 202a and the conductive lower surface 102S.

[0091] The waveguide device is used for at least one of transmitting and receiving electromagnetic waves in a predetermined band (hereinafter referred to as the "operating frequency band") (it is also assumed that it will be used in communications). The free space wavelength of the electromagnetic wave at the center frequency in the operating frequency band of the waveguide device is λo. The end of each rod 202 that is in contact with the second member 200 is referred to as the "base." Each rod 202 has a tip 202a and a base 202b.

[0092] The width (size in the X and Y directions) of the rod 202 may be set to less than λo / 2. Furthermore, it is preferable that the length of the diagonal of the XY cross section of the rod 202 is also less than λo / 2. Furthermore, the distance from the base 202b of the rod 202 to the conductive lower surface 102S of the first member 102 may be set to be longer than the height of the rod 202 and less than λo / 2. The distance L from the tip 202a of the rod 202 to the conductive lower surface 102S is set to be less than λo / 2. There is a gap between the tip 202a of the multiple rods 202 and the conductive lower surface 102S.

[0093] Furthermore, the gap between two adjacent rods 202 among the plurality of rods 202 is, for example, less than λo / 2. The width of the gap between two adjacent rods 202 is defined by the shortest distance from one surface (side surface) of the two rods 202 to the other surface (side surface) of the two rods 202. The width of the gap does not need to be constant. As long as it is less than λo / 2, the gap between the rods 202 may have various widths.

[0094] The arrangement of the rods 202 is not limited to the illustrated example, as long as it functions as an artificial magnetic conductor. The rods 202 do not need to be arranged in orthogonal rows and columns, and the rows and columns may intersect at angles other than 90 degrees. The rods 202 do not need to be arranged in a straight line along the rows or columns, and may be distributed without showing a simple regularity. The shape and size of each rod 202 may also vary depending on its position on the second member 200.

[0095] Furthermore, the surface 124c of the artificial magnetic conductor formed by the tips 202a of the multiple rods 202 does not need to be strictly flat, but may be a plane with minute irregularities or a curved surface. Furthermore, the height of each rod 202 does not need to be uniform, and individual rods 202 may have a variety of shapes as long as the arrangement of the rods 202 can function as an artificial magnetic conductor. Each rod 202 is not limited to the rectangular column shape shown in the figure, and may be cylindrical, for example. Furthermore, each rod 202 does not need to be simply columnar. An artificial magnetic conductor can also be realized by a structure other than an arrangement of rods 202, and a variety of artificial magnetic conductors can be used in the waveguide device of the present disclosure. The height of the rod 202, i.e., the length from the base 202b to the tip 202a, can be set to a value shorter than the distance (less than λo / 2) between the conductive lower surface 102S and the conductive upper surface 200S, for example, λo / 4.

[0096] 3(c), conductive upper surface 200S is planar, but the embodiment of the present disclosure is not limited thereto. For example, conductive upper surface 200S may be the bottom of a surface whose cross section parallel to the XZ plane is shaped like a U or V. Conductive upper surface 200S has such a structure when rod 202 has a shape (tapered shape) in which the width increases from tip 202a to base 202b. Even with such a structure, the illustrated device can function as a waveguide device according to the embodiment of the present disclosure as long as the distance between conductive lower surface 102S and conductive upper surface 200S is shorter than half the wavelength λo. [Explanation of symbols]

[0097] 1, 1A to 1D, 1H, 1K, 1L...waveguide device, 2, 2A...IC mounting substrate, 3, 3C...first waveguide, 4, 4A to 4H...WRG structure portion, 5...second waveguide, 10...millimeter-wave IC (MMIC), 11...transmitting / receiving terminal, 12...SG terminal, 100...substrate, 101...ground, 102...first member, 102S...conductive lower surface, 103...peripheral conductor, 104...through hole, 111...through via hole, 200...second member, 200S...conductive upper surface Surface, 201...ridge, 201a...ridge front end face, 201b...ridge rear end face, 201S...waveguide surface, 201t, 201st...thick portion, 202...rod, 202A to 202D, 202G to H...rod-shaped conductors, 202E, F, K...wall portion, 203...opening portion, 204B...through hole, 206...space, 210...electromagnetic wave shielding wall, 300, 300C, 310...core conductor, 302...feed waveguide, 300Cc, 303, 308...bottom feed conductor

Claims

1. a first member having an upper surface and a conductive lower surface; a second member disposed on a lower surface side of the first member and having a conductive upper surface; a first waveguide including a core conductor that passes through the first member in the vertical direction and is not in contact with the conductive lower surface, and a peripheral conductor that is disposed around the core conductor along the core conductor with an insulator interposed therebetween and that is in contact with the conductive lower surface of the first member; a ridge disposed between the first member and the second member, the ridge having a waveguide surface that is a strip-shaped conductive upper surface facing the conductive lower surface of the first member; a second waveguide formed by the waveguide surface of the ridge and the conductive lower surface of the first member; an electromagnetic wave blocking wall disposed between the first member and the second member and adjacent to the second waveguide; a lower end of the core conductor extending downward in the first member is connected by high frequency coupling to an end side surface of the ridge disposed laterally opposite the lower end, The waveguide device further comprises a rod-shaped conductor or a wall portion having a conductive side surface facing the end side surface across the lower end portion of the core conductor.

2. The waveguide device according to claim 1 , wherein the rod-shaped conductor has a gap between its upper surface and the conductive lower surface of the first member.

3. The waveguide device according to claim 1 , wherein the rod-shaped conductor has an upper surface in contact with the conductive lower surface of the first member.

4. the rod-shaped conductor is a wall portion whose upper surface is in contact with or high-frequency coupled to the conductive lower surface of the first member, 2. The waveguide device according to claim 1, wherein the width of the wall portion in a direction along the extension direction of the ridge and in a direction perpendicular to the height direction is equal to or greater than 1 / 4 of the free space wavelength λo of an electromagnetic wave at a center frequency of an operating frequency band.

5. On the upper surface side of the first member, a substrate having an upper surface and a lower surface, the core conductor and the peripheral conductor penetrating the interior in the vertical direction; a high-frequency circuit disposed on the upper surface or on the upper surface side of the substrate, the high-frequency circuit having a terminal for transmitting or receiving and a signal ground terminal; 2. The waveguide device according to claim 1, further comprising: an upper power supply section arranged on the upper surface of the substrate and electromagnetically connecting a terminal of the high-frequency circuit that transmits or receives signals to an end of the core conductor on the upper surface side of the substrate; and wherein the signal ground terminal of the high-frequency circuit contacts the conductive lower surface of the first member.

6. The waveguide device according to claim 5 , wherein the upper feed portion is a waveguide formed by a microstrip line, a coplanar line, or a post wall.

7. 6. The waveguide device according to claim 5, wherein the upper power supply portion is configured to bring the terminal for transmitting or receiving of the high-frequency circuit into contact with the end of the core conductor on the upper surface side of the substrate, and to bring the signal ground terminal of the high-frequency circuit into contact with the peripheral conductor.

8. 6. The waveguide device according to claim 5, wherein the core conductor and the peripheral conductor each comprise a single conductor, and the single peripheral conductor is disposed adjacent to the single core conductor.

9. 6. The waveguide device according to claim 5, wherein the core conductor is made of one conductor, the peripheral conductor is made of two conductors, and the one core conductor is disposed between the two peripheral conductors.

10. 6. The waveguide device according to claim 5, wherein the core conductor consists of one conductor, the peripheral conductor consists of multiple linear conductors, and the multiple peripheral conductors are arranged along a portion of the outer periphery of the single core conductor, or half of the multiple peripheral conductors are arranged along a portion of the outer periphery of the single core conductor, and the remaining half of the multiple peripheral conductors are arranged along the periphery of another portion opposite the portion of the outer periphery.

11. 6. The waveguide device according to claim 5, wherein the core conductor consists of one conductor, the peripheral conductor consists of a plurality of linear conductors or a plurality of plate-shaped conductors, and the plurality of peripheral conductors are arranged along approximately the entire circumference of the outer periphery of the one core conductor.

12. 6. The waveguide device according to claim 5, wherein the core conductor is made of one conductor, and the peripheral conductor is made of one cylindrical conductor, and the peripheral conductor is disposed so as to surround the outer periphery of the one core conductor.

13. The waveguide device according to claim 5 , wherein the first member is formed of a ground pattern formed on the lower surface of the substrate.

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