Waveguide connection structure

Abstract

This waveguide connection structure electrically connects a waveguide (11) provided to a substrate (10) and a waveguide (21) provided to a metal member (20). The substrate (10) has: a conductor (14) provided to one end of the waveguide (11) and formed to have a length exceeding the length from the opening of the waveguide (11) to λg / 4; and a conductor (13) provided to the other end of the waveguide (11) and formed in a plate shape. The metal member (20) has the bottom surface (20a) where the waveguide (21) opens. The bottom surface (20a) of the metal member (20) and the top surface (13a) of the conductor (13), the top surface facing the conductor (14), are arranged in parallel.

Description

Waveguide connection structure

[0001] The present disclosure relates to a waveguide connection structure.

[0002] Two waveguides may be connected to transmit a high-frequency signal. In this case, if a gap occurs at the connection between the connected waveguides, the high-frequency signal will leak through the gap. Patent Document 1 discloses a waveguide connection structure. This waveguide connection structure includes a choke groove in a substrate on which one of the waveguides is mounted, with the aim of suppressing leakage of the high-frequency signal from the connection.

[0003] JP 2008-113318 A

[0004] The choke groove disclosed in Patent Document 1 is composed of a conductor pattern provided so as to surround the periphery of the end of the waveguide, an opening in the conductor pattern that exposes the dielectric, and a dielectric transmission line that is connected to the opening and has a short-circuit surface at its tip. Therefore, the inclusion of the choke groove in the waveguide connection structure disclosed in Patent Document 1 may lead to an increase in size.

[0005] The substrate is used not only for the waveguide connection structure but also for other wiring unrelated to the waveguide connection structure. Therefore, if the waveguide connection structure is large, the substrate will be monopolized by the connection structure. As a result, there is a risk that other wiring cannot be installed on the substrate.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a waveguide connection structure that can reduce the size of the waveguide connection portion without providing a choke groove portion.

[0007] The waveguide connection structure according to the present disclosure is a waveguide connection structure that electrically connects a first waveguide provided on a substrate and a second waveguide provided on a metal member, wherein the substrate has a one-end conductor provided at one end of the first waveguide and formed to a length exceeding λg / 4 from the opening of the first waveguide, and a other-end conductor provided at the other end of the first waveguide and formed in a flat plate shape, the metal member has a metal surface where the second waveguide opens, and the metal surface is arranged parallel to an opposing surface of the other-end conductor that faces the one-end conductor.

[0008] According to the present disclosure, the connecting portion of the waveguide can be made smaller without providing a choke groove portion.

[0009] 1 is a longitudinal sectional view of a waveguide connection structure according to embodiment 1. FIG. 2 is a top view of a substrate according to embodiment 1. FIG. 3 is a bottom view of a metal member according to embodiment 1. FIG. 4 is a longitudinal sectional view of a waveguide connection structure according to embodiment 2. FIG. 5 is a top view of a substrate according to embodiment 2. FIG. 6 is a longitudinal sectional view of a waveguide connection structure according to embodiment 3. FIG. 7 is a longitudinal sectional view of a waveguide connection structure according to embodiment 4. FIG. 8 is a top view of a substrate according to embodiment 4. FIG. 9 is a top view of another substrate according to embodiment 4. FIG. 10 is a longitudinal sectional view of a waveguide connection structure according to embodiment 5. FIG. 11 is a top view of a substrate according to embodiment 5. FIG. 12 is a longitudinal sectional view of a waveguide connection structure according to embodiment 6. FIG. 13 is a longitudinal sectional view of a waveguide connection structure according to embodiment 7. FIG. 14 is a bottom view of a substrate according to embodiment 7. FIG. 15 is a top view of a substrate according to embodiment 7.

[0010] In order to explain the present disclosure in more detail, embodiments of the present disclosure will be described below with reference to the accompanying drawings.

[0011] Embodiment 1. A waveguide connection structure according to embodiment 1 will be described with reference to Fig. 1 to Fig. 3. Fig. 1 is a vertical cross-sectional view of the waveguide connection structure according to embodiment 1. Fig. 2 is a top view of a substrate 10 according to embodiment 1. Fig. 3 is a bottom view of a metal member 20 according to embodiment 1.

[0012] As shown in Fig. 1, the three-dimensional Cartesian coordinate system in the waveguide connection structure according to the first embodiment is defined by three axes, an X axis, a Y axis, and an X axis, which are orthogonal to each other in space. Fig. 1 shows an example in which the horizontal direction (or width direction) of the connection structure is the X axis, the vertical direction of the connection structure is the Y axis, and the height direction (or thickness direction) of the connection structure is the Z axis. The arrows on the X axis, Y axis, and Z axis indicate the positive directions of the respective axes.

[0013] The waveguide connection structure according to the first embodiment is for electrically connecting the waveguide 11 of the substrate 10 and the waveguide 21 of the metal member 20. In this case, a high-frequency signal input to the feed point 12 of the waveguide 11 flows toward the feed point 22 of the waveguide 21 and is then output from the feed point 22 to a high-frequency circuit or the like. Alternatively, a high-frequency signal input to the feed point 22 of the waveguide 21 flows toward the feed point 12 of the waveguide 11 and is then output from the feed point 12 to a high-frequency circuit or the like.

[0014] 1 also shows a case where an unintended gap S occurs between the waveguides 11 and 21. When the gap S occurs between the waveguides 11 and 21, the waveguides 11 and 21 are not electrically connected. Therefore, if no measures are taken to transmit and receive high-frequency signals between the waveguides 11 and 21, the high-frequency signals will leak from the gap S, and the power of the high-frequency signals transmitted through the waveguides 11 and 21 will decrease.

[0015] That is, since the waveguide 11 and the waveguide 21 are designed to be conductive, if the connection structure between them can be ideally manufactured, the waveguides 11 and 21 will be conductive. Therefore, high-frequency signals can be transmitted without the need for a separate structure. On the other hand, even if an unintended gap S occurs due to a manufacturing error or the like, high-frequency signals can be transmitted by adopting the waveguide connection structure according to embodiment 1.

[0016] In the above description, it is assumed that the gap S is not intended, but the waveguides 11 and 71 may be designed with the gap S intended.

[0017] The substrate 10 has a waveguide 11, conductors 13 to 15, and a dielectric 16. The waveguide 11 constitutes a first waveguide, the conductor 13 constitutes the other end conductor, and the conductor 14 constitutes one end conductor and a connecting portion.

[0018] The waveguide 11 has a cylindrical shape. The cross section of the opening (waveguide) of the waveguide 11 is substantially rectangular. The long side of the opening of the waveguide 11 extends in the Y-axis direction. The short side of the opening of the waveguide 11 extends in the X-axis direction. Such a waveguide 11 can be realized, for example, by providing a through-hole extending in the Z-axis direction in the substrate 10, and then plating the surface of the through-hole to form the conductor 15.

[0019] The conductor 13 is provided in a flange shape on the other end of the conductor 15. The conductor 13 is formed in a flat plate shape and is arranged parallel to the X-Y plane. The length of the conductor 13 in the X-axis direction exceeds the distance λg / 4 from the long side of the waveguide 11. The length of the conductor 13 in the Y-axis direction exceeds the distance λg / 4 from the short side of the waveguide 11, or exceeds the length of the long side of the waveguide 11. Such a conductor 13 is realized by edging copper foil attached to the lower surface of the dielectric 16. Here, λg is the effective wavelength of the high-frequency signal within the substrate.

[0020] Conductor 14 is provided in a flange shape on one end of conductor 15. Conductor 13 is formed in a flat plate shape and is arranged parallel to the X-Y plane. The length of conductor 14 in the X-axis direction is the length from the long side of waveguide 11 to λg / 4. Such conductor 14 is realized, for example, by edging copper foil attached to the upper surface of dielectric 16.

[0021] The dielectric 16 is arranged to surround the periphery of the waveguide 11. The dielectric 16 is also arranged in the Z-axis direction between the upper surface 13a of the conductor 13 and the lower surface 14a of the conductor 14. The dielectric 16 abuts against the upper surface 13a of the conductor 13 and the lower surface 14a of the conductor 14.

[0022] The metal member 20 has a waveguide 21 and a feeding point 22 .

[0023] The waveguide 21 is provided in approximately the center of the metal member 20. The cross section of the opening (waveguide) of this waveguide 21 is approximately rectangular. The long side of the opening of the waveguide 21 extends in the Y-axis direction. The short side of the opening of the waveguide 21 extends in the X-axis direction. Such a waveguide 21 is realized, for example, by providing a through hole extending in the Z-axis direction in the metal member 20, and then plating the surface of the through hole to form a conductor.

[0024] The metal member 20 also has a lower surface 20a. This lower surface 20a is disposed so as to be parallel to the X-Y plane. That is, the lower surface 20a is parallel to the upper surface 13a of the conductor 13 and the lower surface 14a of the conductor 14. The length of the lower surface 20a in the X-axis direction exceeds the distance λg / 4 from the long side of the waveguide 11. The length of the lower surface 20a in the Y-axis direction exceeds the distance λg / 4 from the short side of the waveguide 11. The upper surface 13a constitutes the opposing surface, and the lower surface 20a constitutes the metal surface.

[0025] Next, an operation when using the waveguide connection structure according to the first embodiment will be described. In the following description, only the operation on the right side (positive side in the X-axis direction) from the waveguide 11 in Fig. 1 will be described. The operation on the left side (negative side in the X-axis direction) from the waveguide 11 is a mirror image of the operation on the right side, so the description of the operation on the left side will be omitted.

[0026] 1, if a gap S occurs between the waveguides 11 and 21, the high-frequency signal is radiated from the discontinuity point 17 where the conductor 14 is discontinued. Next, the high-frequency signal propagates in a parallel-plate mode between the upper surface 13a of the conductor 13 and the lower surface 20a of the metal member 20.

[0027] At this time, the high-frequency signal is divided into two components. The first component propagates from discontinuity point 17 toward the positive side of the X-axis direction within gap S. The second component propagates through dielectric 16 toward the negative side of the X-axis direction, is reflected by conductor 15, and then propagates through dielectric 16 toward the positive side of the X-axis direction.

[0028] When the two components have approximately equal amplitudes and opposite phases, they cancel each other out, thereby suppressing leakage of the high-frequency signal from the gap S. As a result, the power loss of the high-frequency signal transmitted between the waveguide 11 and the waveguide 21 is reduced.

[0029] The length of the conductor 13 in the X-axis direction depends on the relative dielectric constant of the dielectric 16. The larger the relative dielectric constant of the dielectric 16, the smaller λg becomes, and accordingly the length of the conductor 13 in the X-axis direction also becomes smaller. The relative dielectric constant of the dielectric 16 that can reduce the size of the waveguide connection structure while maintaining performance is, for example, 2 or more.

[0030] It should be noted that the substrate 10 does not necessarily need to include the dielectric 16. In this case, the substrate 10 will only include the waveguide 11 and the conductors 13 to 15. The conductors 13 to 15 may be manufactured by cutting or using a 3D printer. The conductors 13 to 15 may also be molded from a resin material and then plated on their surfaces. Therefore, the portion of the substrate 10 where the dielectric 16 is installed will be hollow, and the length of the conductor 13 in the X-axis direction will be λg / 4 to λ / 4, where λ is the wavelength of the high-frequency signal in free space.

[0031] As described above, the waveguide connection structure according to the first embodiment electrically connects the waveguide 11 provided on the substrate 10 and the waveguide 21 provided on the metal member 20. The substrate 10 has the conductor 14 provided at one end of the waveguide 11 and formed to a length exceeding λg / 4 from the opening of the waveguide 11, and the conductor 13 provided at the other end of the waveguide 11 and formed in a flat plate shape. The metal member 20 has a lower surface 20a where the waveguide 21 opens. The upper surface 13a of the conductor 13 facing the conductor 14 and the lower surface 20a of the metal member 20 are arranged parallel to each other. Therefore, the waveguide connection structure according to the first embodiment can reduce the size of the waveguide connection portion without providing a choke groove portion.

[0032] Embodiment 2 A waveguide connection structure according to embodiment 2 will be described with reference to Figures 4 and 5. Figure 4 is a longitudinal cross-sectional view of the waveguide connection structure according to embodiment 2. Figure 5 is a top view of a substrate 30 according to embodiment 2. Note that components having the same functions as those described in embodiment 1 above are given the same reference numerals, and descriptions thereof will be omitted.

[0033] As shown in FIG. 4, the waveguide connection structure according to the second embodiment electrically connects the waveguide 11 of the substrate 30 and the waveguide 21 of the metal member 20 .

[0034] The substrate 30 has a waveguide 11, conductors 13 and 15, a dielectric 16, and a conductor 31. That is, the substrate 30 according to the second embodiment has a structure including the conductor 31 instead of the conductor 14 of the substrate 10 according to the first embodiment. The conductor 31 constitutes a one-end conductor.

[0035] 4 and 5, the conductor 31 is provided in a flange shape on the other end of the conductor 15. The conductor 31 is formed in a flat plate shape and is disposed so as to be parallel to the XY plane.

[0036] The conductor 31 also has two holes 31a. These holes 31a are provided on both sides in the width direction of the opening of the waveguide 11. The conductor 31 has the holes 31a, so that the dielectric 16 can be exposed from the holes 31a.

[0037] The length of the hole 31a in the Y-axis direction is equal to or greater than the length of the long side of the waveguide 11. The length of the hole 31a in the X-axis direction is a length that allows a high-frequency signal to propagate through the hole 31a to the dielectric 16. The length of the hole 31a in the X-axis direction is, for example, λ / 8 or greater. Such a conductor 31 is realized, for example, by edging copper foil attached to the upper surface of the dielectric 16. The hole 31a constitutes a one-end side hole.

[0038] Next, we will explain the operation when using the waveguide connection structure according to embodiment 2. The waveguide connection structure according to embodiment 2 is also symmetrical with respect to the waveguide 11 shown in Figure 4, and of the operations on the left and right sides, we will explain the operation on the right side as a representative.

[0039] 4, if a gap S occurs between the waveguides 11 and 21, the high-frequency signal is radiated from the discontinuity point 17 where the conductor 31 is discontinued. Next, the high-frequency signal propagates in a parallel-plate mode between the upper surface 13a of the conductor 13 and the lower surface 20a of the metal member 20.

[0040] At this time, the high-frequency signal is divided into two components. The first component propagates from discontinuity point 17 toward the positive side of the X-axis direction within gap S. The second component propagates through dielectric 16 toward the negative side of the X-axis direction, is reflected by conductor 15, and then propagates through dielectric 16 toward the positive side of the X-axis direction.

[0041] The two components do not move outside the hole 31a in the width direction, but are completed at the hole 31a. In other words, the hole 31a limits the operating range of the two components of the high-frequency signal. When the two components are roughly equal in amplitude and opposite in phase, they cancel each other out. This suppresses leakage of the high-frequency signal from the gap S. As a result, the power loss of the high-frequency signal transmitted between the waveguide 11 and the waveguide 21 is reduced.

[0042] As described above, the waveguide connection structure according to the second embodiment can reduce the size of the waveguide connection portion without providing a choke groove portion.

[0043] Embodiment 3 A waveguide connection structure according to embodiment 3 will be described with reference to Fig. 6. Fig. 6 is a longitudinal cross-sectional view of the waveguide connection structure according to embodiment 3. Note that components having the same functions as those described in the above-mentioned embodiments 1 and 2 are given the same reference numerals, and descriptions thereof will be omitted.

[0044] As shown in FIG. 6, the waveguide connection structure according to the third embodiment electrically connects the waveguide 11 of the substrate 40 and the waveguide 21 of the metal member 20 .

[0045] The substrate 40 has a waveguide 11, conductors 13 and 15, a dielectric 16, a conductor 31, and a conductor 41. That is, the substrate 30 according to the third embodiment has a structure in which the conductor 41 is added to the structure of the substrate 30 according to the second embodiment. The conductor 41 constitutes an intermediate layer conductor.

[0046] The conductor 41 is disposed between the conductor 13 and the conductor 31. The conductor 41 is formed in a flat plate shape and is disposed so as to be parallel to the XY plane. That is, the conductors 13, 31, and 41 are disposed so as to be parallel to one another. The conductor 41 is connected to the outer periphery of the conductor 15. Although one conductor 41 is provided between the conductor 13 and the conductor 31, multiple conductors 41 may also be provided.

[0047] The conductor 41 also has two holes 41a, which are provided on both sides in the width direction of the opening of the waveguide 11. Each hole 41a is disposed opposite a corresponding hole 31a in the Z-axis direction.

[0048] The length of the hole 41a in the Y-axis direction is equal to or greater than the length of the long side of the waveguide 11. The length of the hole 41a in the X-axis direction is a length that allows a high-frequency signal to propagate through the hole 41a to the dielectric 16. The length of the hole 41a in the X-axis direction is, for example, λ / 8 or greater. The hole 41a constitutes an intermediate layer side hole.

[0049] Next, we will explain the operation when using the waveguide connection structure according to embodiment 3. The waveguide connection structure according to embodiment 3 is also symmetrical with respect to the waveguide 11 shown in Figure 6, and of the operations on the left and right sides, we will explain the operation on the right side as a representative.

[0050] 6, if a gap S occurs between the waveguides 11 and 21, the high-frequency signal will be radiated from the discontinuity point 17 where the conductor 41 is discontinued. The high-frequency signal will then propagate in a parallel plate mode between the upper surface 13a of the conductor 13 and the lower surface 20a of the metal member 20. Although the conductors 31 and 41 are disposed between the upper surface 13a of the conductor 13 and the lower surface 20a of the metal member 20, this does not affect the propagation of the high-frequency signal.

[0051] At this time, the high-frequency signal is divided into two components. The first component propagates from discontinuity point 17 toward the positive side of the X-axis direction within gap S. The second component propagates through dielectric 16 toward the negative side of the X-axis direction, is reflected by conductor 15, and then propagates through dielectric 16 toward the positive side of the X-axis direction.

[0052] The two components do not move beyond the holes 31a, 41a in the width direction, but are completed at the holes 31a, 41a. In other words, the holes 31a, 41a limit the operating range of the two components of the high-frequency signal. When the two components are roughly equal in amplitude and opposite in phase, they cancel each other out. This suppresses leakage of the high-frequency signal from the gap S. As a result, power loss of the high-frequency signal transmitted between the waveguide 11 and the waveguide 21 is reduced.

[0053] Furthermore, the substrate 40 is not only provided with the waveguide connection structure, but is also used for other wiring unrelated thereto. The waveguide connection structure according to the third embodiment includes the conductor 41 for such wiring, but this does not affect the waveguide connection in any way.

[0054] As described above, the waveguide connection structure according to the third embodiment can reduce the size of the waveguide connection portion without providing a choke groove portion.

[0055] Fourth Embodiment A waveguide connection structure according to a fourth embodiment will be described with reference to Figs. 7 to 9. Fig. 7 is a longitudinal cross-sectional view of the waveguide connection structure according to the fourth embodiment. Fig. 8 is a top view of a substrate 50 according to the fourth embodiment. Fig. 9 is a top view of another substrate 50 according to the fourth embodiment. Note that components having the same functions as those described in the first to third embodiments above are given the same reference numerals, and their description will be omitted.

[0056] As shown in FIG. 7, the waveguide connection structure according to the fourth embodiment electrically connects the waveguide 11 of the substrate 50 and the waveguide 21 of the metal member 20 .

[0057] The substrate 50 has a waveguide 11, conductors 13 and 15, a dielectric 16, conductors 31 and 41, and a conductor 51. That is, the substrate 50 of the fourth embodiment has a structure in which the conductor 51 is added to the structure of the substrate 40 of the third embodiment. The conductor 51 constitutes a first connecting conductor.

[0058] The multiple conductors 51 are arranged to extend in the Z-axis direction and are formed in an axial shape. Each conductor 51 is connected to conductors 13, 31, and 41. These conductors 51 are provided on the widthwise outer sides of holes 31a and 41a of conductors 31 and 41, respectively, with waveguide 11 at the center. The conductors 51 on both widthwise outer sides are arranged side by side along the Y-axis direction. The conductors 51 are, for example, through-holes.

[0059] In this way, by including the conductor 51, the substrate 50 can absorb the leaked high-frequency signal when a manufacturing defect occurs in the conductors 31, 41, etc., causing a high-frequency signal to leak from the connection portion or gap S of the waveguides 11, 21. Therefore, the substrate 50 can suppress leakage of the high-frequency signal outside the substrate 50. Furthermore, even if the substrate 50 includes the conductor 51, this does not affect the connection between the waveguide 11 of the substrate 50 and the waveguide 21 of the metal member 20.

[0060] Furthermore, as described above, the operation of the above two components in the high-frequency signal radiated from the discontinuity point 17 in the gap S is completed by the holes 31a, 41a of the conductors 31, 41. In contrast, the conductor 51 is provided on the outside in the width direction of the holes 31a, 41a of the conductors 31, 41. Therefore, the conductor 51 does not affect the operation of the above two components.

[0061] The operation of the waveguide connection structure according to the fourth embodiment is the same as that of the waveguide connection structure according to the third embodiment described above, and therefore a description thereof will be omitted.

[0062] 8 shows an example in which four conductors 51 are provided on the outer sides of the holes 31a and 41a of the conductors 31 and 41 in the width direction. The number and installation positions of the conductors 51 can be adjusted as appropriate. For example, the conductors 51 may be provided as shown in FIG. 9.

[0063] 9 includes a plurality of conductors 51 on both sides of the waveguide 11 in the width direction, as well as a plurality of conductors 51 on both sides of the waveguide 11 in the vertical direction. Specifically, these conductors 51 are provided on the vertical outer sides of the holes 31a and 41a of the conductors 31 and 41, respectively, with the waveguide 11 at the center. Furthermore, the conductors 51 on both vertical outer sides are arranged side by side along the X-axis direction. Furthermore, the conductors 51 are connected to the conductors 13, 31, and 41.

[0064] As described above, the waveguide connection structure according to the fourth embodiment can reduce the size of the waveguide connection portion without providing a choke groove portion.

[0065] Fifth Embodiment A waveguide connection structure according to a fifth embodiment will be described with reference to Figs. 10 and 11. Fig. 10 is a longitudinal cross-sectional view of the waveguide connection structure according to the fifth embodiment. Fig. 11 is a top view of a substrate 60 according to the fifth embodiment. Note that components having the same functions as those described in the first to third embodiments above are denoted by the same reference numerals, and their description will be omitted.

[0066] As shown in FIG. 10, the waveguide connection structure according to the fifth embodiment electrically connects the waveguide 11 of the substrate 60 and the waveguide 21 of the metal member 20 .

[0067] The substrate 60 has a waveguide 11, conductors 13 and 15, a dielectric 16, conductors 31 and 41, and a conductor 61. That is, the substrate 60 according to the fifth embodiment has a structure in which the conductor 61 is added to the structure of the substrate 40 according to the third embodiment. The conductor 61 constitutes a second connecting conductor.

[0068] The conductors 61 are arranged to extend in the Z-axis direction and are formed in an axial shape. Each conductor 61 is connected to the conductors 13 and 41. These conductors 61 are arranged to surround the periphery of the waveguide 11 and the holes 31 a and 41 a of the conductors 31 and 41.

[0069] Specifically, the plurality of conductors 61 are provided on the widthwise outer sides of the holes 31a and 41a of the conductors 31 and 41, respectively, with the waveguide 11 at the center. These conductors 61 are arranged side by side along the Y-axis direction. Furthermore, the plurality of conductors 61 are provided on the vertically outer sides of the holes 31a and 41a of the conductors 31 and 41, respectively, with the waveguide 11 at the center. These conductors 61 are arranged side by side along the X-axis direction. The conductors 61 are blind via holes.

[0070] In this way, by including the conductor 61, the substrate 60 can absorb the leaked high-frequency signal when a manufacturing defect occurs in the conductors 31, 41, etc., causing a high-frequency signal to leak from the connection portion or gap S of the waveguides 11, 21. Therefore, the substrate 60 can suppress leakage of the high-frequency signal outside the substrate 60. Furthermore, even if the substrate 60 includes the conductor 61, this does not affect the connection between the waveguide 11 of the substrate 60 and the waveguide 21 of the metal member 20.

[0071] Furthermore, as described above, the operation of the above two components in the high-frequency signal radiated from the discontinuity point 17 in the gap S is completed by the holes 31a, 41a of the conductors 31, 41. In contrast, the conductor 61 is provided on the outside in the width direction of the holes 31a, 41a of the conductors 31, 41. Therefore, the conductor 61 does not affect the operation of the above two components.

[0072] The operation of the waveguide connection structure according to the fifth embodiment is the same as that of the waveguide connection structure according to the third embodiment described above, and therefore a description thereof will be omitted.

[0073] 11 shows an example in which four conductors 61 are provided on the widthwise outer sides of the holes 31 a and 41 a of the conductors 31 and 41, respectively, and four conductors 61 are provided on the vertical outer sides of the holes 31 a and 41 a of the conductors 31 and 41. The number and installation positions of the conductors 61 can be adjusted as appropriate.

[0074] As described above, the waveguide connection structure according to the fifth embodiment can reduce the size of the waveguide connection portion without providing a choke groove portion.

[0075] Sixth Embodiment A waveguide connection structure according to a sixth embodiment will be described with reference to Fig. 12. Fig. 12 is a longitudinal cross-sectional view of the waveguide connection structure according to the sixth embodiment. Note that components having the same functions as those described in the first embodiment above are given the same reference numerals, and descriptions thereof will be omitted.

[0076] As shown in FIG. 12, the waveguide connection structure according to the sixth embodiment is a structure including a substrate 70 instead of the metal member 20 of the waveguide connection structure according to the first embodiment.

[0077] The waveguide connection structure according to the sixth embodiment is for electrically connecting the waveguide 11 of the substrate 10 and the waveguide 71 of the substrate 70. In this case, a high-frequency signal input to the feed point 12 of the waveguide 11 flows toward the feed point 72 of the waveguide 71 and is then output from the feed point 72 to a high-frequency circuit or the like. Alternatively, a high-frequency signal input to the feed point 72 of the waveguide 71 flows toward the feed point 12 of the waveguide 11 and is then output from the feed point 12 to a high-frequency circuit or the like.

[0078] The substrate 10 constitutes a first substrate, and the waveguide 11 constitutes a first waveguide. The substrate 70 constitutes a second substrate, and the waveguide 71 constitutes a second waveguide.

[0079] 12 shows a case where an unintended gap S occurs between the waveguides 11 and 71. When the gap S occurs between the waveguides 11 and 71, the waveguides 11 and 71 are not electrically connected. Therefore, if no measures are taken to transmit and receive high-frequency signals between the waveguides 11 and 71, the high-frequency signals will leak from the gap S, and the power of the high-frequency signals transmitted through the waveguides 11 and 71 will decrease.

[0080] That is, since the waveguide 11 and the waveguide 71 are designed to be conductive, if the connection structure between them can be ideally manufactured, the waveguide 11 and the waveguide 71 will be conductive. Therefore, high-frequency signals can be transmitted without requiring a separate structure. On the other hand, even if an unintended gap S occurs due to a manufacturing error or the like, high-frequency signals can be transmitted by adopting the waveguide connection structure according to embodiment 6.

[0081] The substrate 70 includes a waveguide 71 , conductors 73 and 74 , and a dielectric 75 .

[0082] The waveguide 71 has a cylindrical shape. The waveguide 71 is formed to extend in the Z-axis direction. The waveguide 71 is disposed opposite the waveguide 11 in the Z-axis direction. The cross section of the opening of the waveguide 71 has the same shape and area as the cross section of the opening of the waveguide 11. The waveguide 71 is realized, for example, by providing a through hole extending in the Z-axis direction in the substrate 70, and then plating the surface of the through hole to form the conductor 74.

[0083] The conductor 73 is provided in a flange shape on one end of the conductor 74. The conductor 73 is formed in a flat plate shape, and its lower surface 73a is arranged parallel to the X-Y plane. The lower surface 73a of the conductor 73 is also arranged facing the substrate 10. The length of the lower surface 73a of the conductor 73 in the X-axis direction exceeds the length from the long side of the waveguide 71 to λg / 4. The length of the lower surface 73a of the conductor 73 in the Y-axis direction exceeds the length from the short side of the waveguide 71 to λg / 4. The lower surface 73a of the conductor 73 is realized by edging copper foil attached to the lower surface of the dielectric 75, which will be described later. The lower surface 73a constitutes the conductor surface.

[0084] The dielectric 75 is disposed so as to surround the periphery of the waveguide 71. The dielectric 75 is also provided on the upper surface of the conductor 73 and is formed so as not to extend beyond the other end of the waveguide 71. The substrate 70 does not necessarily need to include the dielectric 75.

[0085] Next, an operation when using the waveguide connection structure according to embodiment 6 will be described. In the following explanation, only the operation on the right side (positive side in the X-axis direction) from the waveguide 11 in Fig. 12 will be described. The operation on the left side (negative side in the X-axis direction) from the waveguide 11 is a mirror image of the operation on the right side, so the explanation of the operation on the left side will be omitted.

[0086] 12, if a gap S occurs between the waveguides 11 and 71, the high-frequency signal is radiated from a discontinuity point 17 where the conductor (one-end conductor) 14 is discontinued. Next, the high-frequency signal propagates in a parallel-plate mode between the upper surface (opposing surface) 13a of the conductor (other-end conductor) 13 and the lower surface 73a of the conductor 73.

[0087] At this time, the high-frequency signal is divided into two components. The first component propagates from discontinuity point 17 toward the positive side of the X-axis direction within gap S. The second component propagates through dielectric 16 toward the negative side of the X-axis direction, is reflected by conductor 15, and then propagates through dielectric 16 toward the positive side of the X-axis direction.

[0088] When the two components have approximately equal amplitudes and opposite phases, they cancel each other out, thereby suppressing leakage of the high-frequency signal from the gap S. As a result, the power loss of the high-frequency signal transmitted between the waveguide 11 and the waveguide 71 is reduced.

[0089] As described above, the waveguide connection structure according to the sixth embodiment electrically connects waveguide 11 provided on substrate 10 and waveguide 71 provided on substrate 70. Substrate 10 has conductor 14 provided at one end of waveguide 11 and formed to a length exceeding λg / 4 from the opening of waveguide 11, and conductor 13 provided at the other end of waveguide 11 and formed in a flat plate shape. Substrate 70 has bottom surface 73a of conductor 73 where waveguide 71 opens. Top surface 13a of conductor 13 facing conductor 14 and bottom surface 73a of conductor 73 are arranged parallel to each other. Therefore, the waveguide connection structure according to the sixth embodiment can reduce the size of the waveguide connection portion without providing a choke groove.

[0090] Seventh Embodiment A waveguide connection structure according to a seventh embodiment will be described with reference to Figs. 13 to 15. Fig. 13 is a longitudinal cross-sectional view of the waveguide connection structure according to the seventh embodiment. Fig. 14 is a bottom view of a substrate 80 according to the seventh embodiment. Fig. 15 is a top view of a substrate 80 according to the seventh embodiment. Note that components having the same functions as those described in the first embodiment above are given the same reference numerals, and descriptions thereof will be omitted.

[0091] The waveguide connection structure according to the seventh embodiment is for electrically connecting the waveguide 11 of the substrate 10 with the converter 81 of the substrate 80. In this case, a high-frequency signal input to the feed point 12 of the waveguide 11 flows via the converter 81 toward the feed point 82 of the substrate 80, and is then output from the feed point 82 to a high-frequency circuit or the like. Alternatively, a high-frequency signal input to the feed point 82 of the substrate 80 flows via the converter 81 toward the feed point 12 of the waveguide 11, and is then output from the feed point 12 to a high-frequency circuit or the like. The converter 81 will be described in detail later.

[0092] The substrate 10 constitutes a first substrate, the waveguide 11 constitutes a second waveguide, and the substrate 80 constitutes a second substrate.

[0093] 12 shows a case where an unintended gap S occurs between the waveguide 11 and the converter 81. When the gap S occurs between the waveguide 11 and the converter 81, the waveguide 11 and the converter 81 are not electrically connected. Therefore, if no measures are taken to transmit and receive high-frequency signals between the waveguide 11 and the converter 81, the high-frequency signals will leak from the gap S, and the power of the high-frequency signals transmitted through the waveguides 11 and 71 will decrease.

[0094] That is, since the waveguide 11 and the converter 81 are designed to be conductive, if the connection structure between them can be ideally manufactured, the waveguide 11 and the converter 81 will be conductive. Therefore, high-frequency signals can be transmitted without requiring a separate structure. On the other hand, even if an unintended gap S occurs due to a manufacturing error or the like, high-frequency signals can be transmitted by adopting the waveguide connection structure according to embodiment 7.

[0095] As shown in FIGS. 13 to 15, the substrate 80 includes a transition 81 , a conductor 83 , a coupling hole 84 , a conductor 85 , a microstrip line 86 , a transition portion 87 , and a dielectric 88 .

[0096] The converter 81 is a portion that converts from the waveguide to the microstrip line 86, and a portion that converts from the microstrip line 86 to the waveguide. This converter 81 is disposed opposite the waveguide 11 of the substrate 10 in the Z-axis direction. The converter 81 is composed of, for example, a conductor 83, a coupling hole 84, a conversion portion 87, and a dielectric 88, which will be described later. Of these, the conductor 83, the coupling hole 84, and the dielectric 88 constitute the waveguide.

[0097] The conductor 83 is disposed opposite the substrate 10 in the Z-axis direction. The conductor 83 is formed in a flat plate shape and is disposed parallel to the XY plane. The conductor 83 is realized by edging copper foil attached to the underside of a dielectric 88 (described later).

[0098] The upper surface 83a of the conductor 83 forms the ground plane of the microstrip line 86, which will be described later. Therefore, the area of ​​the conductor 83 is large enough to include the microstrip line 86. The lower surface 83b of the conductor 83 forms a connection portion between the substrate 10 and the waveguide 11. The length in the X-axis direction of the lower surface 83b of the conductor 83 exceeds the length from the long side of the waveguide 11 to λg / 4. The length in the Y-axis direction of the lower surface 83b of the conductor 83 exceeds the length from the short side of the waveguide 11 to λg / 4. Therefore, both the upper surface 83a and the lower surface 83b must be conductor surfaces.

[0099] The coupling hole 84 is a through-hole that penetrates the conductor 83 in the Z-axis direction (thickness direction). The coupling hole 84 is also a rectangular through-hole that extends in the Y-axis direction. The coupling hole 84 is disposed opposite the waveguide 11 of the substrate 10 in the Z-axis direction, and is electrically coupled to the waveguide 11.

[0100] The conductor 85 has a microstrip line 86 and a conversion section 87. The microstrip line 86 is connected to the conversion section 87. The conductor 83 is realized by edging copper foil attached to the upper surface of a dielectric 88 (described later).

[0101] The microstrip line 86 is a line that extends in the X-axis direction. Both ends of the microstrip line 86 form feeding points 82.

[0102] The converter 87 is provided in a midway portion of the microstrip line 86. This converter 87 is disposed opposite the coupling hole 84 in the Z-axis direction. That is, the converter 87 is connected to the coupling hole 84 via a dielectric 88, which will be described later. Therefore, the converter 81 passes the high-frequency signal that has passed through the waveguide 11 and the coupling hole 84 in that order to the microstrip line 86 via the converter 87. The converter 81 also passes the high-frequency signal that has passed through the microstrip line 86 to the coupling hole 84 via the converter 87. The shape of the converter 87 can be set arbitrarily.

[0103] The dielectric 88 is provided between the upper surface 83a of the conductor 83 and the lower surface of the conductor 85. It should be noted that the substrate 80 does not necessarily need to include the dielectric 88.

[0104] Next, an operation when using the waveguide connection structure according to the seventh embodiment will be described. In the following explanation, only the operation on the right side (positive side in the X-axis direction) from the waveguide 11 in Fig. 13 will be described. The operation on the left side (negative side in the X-axis direction) from the waveguide 11 is a mirror image of the operation on the right side, so the explanation of the operation on the left side will be omitted.

[0105] 13, if a gap S occurs between the waveguide 11 and the converter 81, the high-frequency signal is radiated from a discontinuity point 17 where the conductor (the conductor on one end side) 14 is discontinued. Next, the high-frequency signal propagates in a parallel plate mode between the upper surface (opposing surface) 13a of the conductor (the conductor on the other end side) 13 and the lower surface 83b of the conductor 83.

[0106] At this time, the high-frequency signal is divided into two components. The first component propagates from discontinuity point 17 toward the positive side of the X-axis direction within gap S. The second component propagates through dielectric 16 toward the negative side of the X-axis direction, is reflected by conductor 15, and then propagates through dielectric 16 toward the positive side of the X-axis direction.

[0107] When the two components have approximately equal amplitudes and opposite phases, they cancel each other out, thereby suppressing leakage of the high-frequency signal from the gap S. As a result, the power loss of the high-frequency signal transmitted between the waveguide 11 and the converter 81 is reduced.

[0108] As described above, the waveguide connection structure according to the seventh embodiment electrically connects the waveguide 11 provided on the substrate 10 with the converter 81 provided on the substrate 80. The substrate 10 includes a conductor 14 provided at one end of the waveguide 11 and having a length greater than λg / 4 from the opening of the waveguide 11, and a flat conductor 13 provided at the other end of the waveguide 11. The substrate 80 includes a microstrip line 86 connected to one end of the converter 81, a coupling hole 84 connected to the other end of the converter 81 and facing the waveguide 11, and a lower surface 83b of the conductor 83 on which the coupling hole 84 opens. The upper surface 13a of the conductor 13 facing the conductor 14 and the lower surface 83b of the conductor 83 are arranged parallel to each other. Therefore, the waveguide connection structure according to the seventh embodiment can reduce the size of the waveguide connection portion without providing a choke groove.

[0109] It should be noted that within the scope of the present disclosure, the embodiments may be freely combined, or any component in each embodiment may be modified, or any component in each embodiment may be omitted.

[0110] The device according to the present disclosure can be made smaller by arranging the opposing surfaces of the conductors on the substrate and the metal surfaces of the metal members in parallel, and is suitable for use in antenna devices and the like.

[0111] 10 Substrate, 11 Waveguide, 12 Feeding point, 13 Conductor, 13a Upper surface, 14 Conductor, 14a Lower surface, 15 Conductor, 16 Dielectric, 17 Discontinuity point, 20 Metal member, 20a Lower surface, 21 Waveguide, 22 Feeding point, 30 Substrate, 31 Conductor, 31a Hole, 40 Substrate, 41 Conductor, 41a Hole, 50 Substrate, 51 Conductor, 60 Substrate, 61 Conductor, 70 Substrate, 71 Waveguide, 72 Feeding point, 73 Conductor, 73a Lower surface, 74 Conductor, 75 Dielectric, 80 Substrate, 81 Transition portion, 82 Feeding point, 83 Conductor, 83a Upper surface, 83b Lower surface, 84 Coupling hole, 85 Conductor, 86 Microstrip line, 87 Transition portion, 88 Dielectric, S gap.

Claims

1. A waveguide connection structure electrically connecting a first waveguide provided on a substrate and a second waveguide provided on a metal member, wherein the substrate has: a one-end conductor provided at one end of the first waveguide, the one-end conductor having a length exceeding λg / 4 from an opening of the first waveguide; and a other-end conductor provided at the other end of the first waveguide, the other-end conductor having a flat plate shape; the metal member has a metal surface through which the second waveguide opens, and an opposing surface of the other-end conductor that faces the one-end conductor is arranged in parallel to the metal surface.

2. The waveguide connection structure according to claim 1, characterized in that the one-end conductor has a one-end hole formed at a position that exceeds a length of λg / 4 from the opening of the first waveguide.

3. The waveguide connection structure according to claim 2, characterized in that the substrate is provided with an intermediate layer conductor between the one end conductor and the other end conductor, the intermediate layer conductor being connected to the first waveguide, and the intermediate layer conductor has an intermediate layer side hole formed at a position exceeding a length of λg / 4 from the opening of the first waveguide.

4. The waveguide connection structure according to claim 3, characterized in that the substrate has a first connection conductor connected to the one end conductor, the other end conductor, and the intermediate layer conductor, and arranged outside the one end side hole and the intermediate layer side hole with the first waveguide as the center.

5. A waveguide connection structure as claimed in claim 3, characterized in that the substrate has a first connection conductor connected to the one end conductor, the other end conductor and the intermediate layer conductor, and arranged so as to surround the first waveguide, the one end side hole and the intermediate layer side hole.

6. The waveguide connection structure according to claim 3, characterized in that the substrate has a second connection conductor connected to the other end conductor and the intermediate layer conductor, and arranged outside the one end side hole and the intermediate layer side hole, with the first waveguide as the center.

7. A waveguide connection structure electrically connecting a first waveguide provided on a first substrate and a second waveguide provided on a second substrate, wherein the first substrate has: a one-end conductor provided at one end of the first waveguide, the one-end conductor having a length exceeding λg / 4 from an opening of the first waveguide; and an other-end conductor provided at the other end of the first waveguide, the other-end conductor having a flat plate shape; the second substrate has a conductor surface on which the second waveguide opens, and an opposing surface of the other-end conductor that faces the one-end conductor is arranged in parallel to the conductor surface.

8. A waveguide connection structure electrically connecting a first waveguide provided on a first substrate and a converter provided on a second substrate, wherein the first substrate has: a one-end conductor provided at one end of the first waveguide, the one-end conductor having a length exceeding λg / 4 from an opening of the first waveguide; and an other-end conductor provided at the other end of the first waveguide, the other-end conductor having a flat plate shape; and the second substrate has a microstrip line connected to one end of the converter, a coupling hole connected to the other end of the converter and facing the first waveguide, and a conductor surface into which the coupling hole opens, and an opposing surface of the other-end conductor facing the one-end conductor and the conductor surface are arranged in parallel.

9. A waveguide connection structure as claimed in any one of claims 1 to 8, characterized in that it comprises a dielectric provided around the first waveguide and disposed between the one end conductor and the other end conductor.

10. The waveguide connection structure according to claim 9, characterized in that the dielectric has a relative dielectric constant of 2 or more.

Images