Waveguide

Abstract

This waveguide is provided with: a dielectric layer; a first conductor layer stacked in a stacking direction of the dielectric layer; a second conductor layer stacked at a position different from that of the first conductor layer in the stacking direction of the dielectric layer; a plurality of first conductor vias electrically connecting the first conductor layer and the second conductor layer; and a connection part electrically connecting two or more second conductor through holes provided in the vicinity of a specific portion where electromagnetic waves are scattered, the specific portion being present in a waveguide portion which is surrounded by the first conductor layer, the second conductor layer, and the plurality of first conductor through holes and through which the electromagnetic waves pass.

Description

Technical Field

[0001] The present disclosure relates to waveguides. Background Art

[0002] A pillar-walled waveguide is a type of transmission line used to transmit high-frequency signals such as microwaves, millimeter waves, and terahertz waves. It consists of a dielectric layer, two conductive layers arranged above and below it, and a conductive via connecting the two conductive layers.

[0003] For example, Patent Document 1 describes a structure formed by connecting two cylindrical waveguides of equal thickness (e.g., the same number of layers) but with different center positions in the stacking direction. In this structure, the two cylindrical waveguides are connected by providing a coupling window.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2008-300934 Summary of the Invention

[0007] However, in the cylindrical-walled waveguide described in Patent Document 1, since the surface area of ​​the conductor increases, the loss in the conductor also increases.

[0008] Non-limiting embodiments of the present disclosure facilitate providing a waveguide capable of suppressing losses.

[0009] A waveguide according to one embodiment of the present disclosure includes: a dielectric layer; a first conductor layer stacked in a stacking direction of the dielectric layer; a second conductor layer stacked at a position different from the first conductor layer in the stacking direction of the dielectric layer; a plurality of first conductor through-holes electrically connecting the first conductor layer and the second conductor layer; and a connecting portion electrically connecting two or more second conductor through-holes provided near a specific location, the specific location being a location in a waveguide portion surrounded by the first conductor layer, the second conductor layer, and the plurality of first conductor through-holes, through which electromagnetic waves pass, and where the electromagnetic waves are scattered.

[0010] According to one embodiment of the present disclosure, loss can be suppressed in a waveguide.

[0011] Further advantages and effects of an embodiment of the present disclosure will be clarified through the description and drawings. These advantages and / or effects are provided by several embodiments and the features described in the description and drawings, but not all of them need to be provided in order to obtain one or more of the same features. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1AThis is a perspective view showing an example of a cylindrical wall waveguide disclosed in Patent Document 1.

[0013] Figure 1B It is along Figure 1A Cross-sectional view taken along the XZ plane along the AA' line.

[0014] Figure 2 This is a perspective view showing an example of a pillar-walled waveguide according to the first embodiment of the present disclosure.

[0015] Figure 3 This is a plan view of the cylindrical waveguide according to the first embodiment of the present disclosure as viewed from the positive direction of the Z axis.

[0016] Figure 4 It is along Figure 3 AA' cross-sectional view taken along the XZ plane.

[0017] Figure 5 It is along Figure 3 BB' cross-sectional view taken along the XZ plane.

[0018] Figure 6 It is along Figure 3 The CC' section view is taken along the YZ plane.

[0019] Figure 7 This is a diagram showing an example of the frequency response of the cylindrical waveguide according to the first embodiment of the present disclosure.

[0020] Figure 8 This is a diagram showing an example of electric field distribution in the pillar-walled waveguide according to the first embodiment of the present disclosure.

[0021] Figure 9 This is a perspective view showing an example of a pillar-walled waveguide according to a second embodiment of the present disclosure.

[0022] Figure 10 This is a plan view of the cylindrical waveguide according to the second embodiment of the present disclosure as viewed from the positive direction of the Z axis.

[0023] Figure 11 It is along Figure 10 AA' cross-sectional view taken along the XZ plane.

[0024] Figure 12 It is along Figure 10 BB' cross-sectional view taken along the XZ plane.

[0025] Figure 13 It is along Figure 10 CC' cross-sectional view taken along the YZ plane.

[0026] Figure 14This is a diagram showing an example of the frequency response of the cylindrical waveguide according to the second embodiment of the present disclosure.

[0027] Figure 15 This is a diagram showing an example of electric field distribution in a pillar-walled waveguide according to the second embodiment of the present disclosure.

[0028] Figure 16 This is a perspective view showing an example of a pillar-walled waveguide according to a third embodiment of the present disclosure.

[0029] Figure 17 This is a plan view of the cylindrical waveguide according to the third embodiment of the present disclosure as viewed from the positive direction of the Z axis.

[0030] Figure 18 It is along Figure 17 AA' cross-sectional view taken along the XZ plane.

[0031] Figure 19 It is along Figure 17 BB' cross-sectional view taken along the XZ plane.

[0032] Figure 20 It is along Figure 17 The CC' section view is taken along the YZ plane.

[0033] Figure 21 This is a diagram showing an example of the frequency response of the cylindrical waveguide according to the third embodiment of the present disclosure.

[0034] Figure 22 This is a diagram showing an example of electric field distribution in a pillar-walled waveguide according to the third embodiment of the present disclosure.

[0035] Figure 23 This is a perspective view showing an example of a pillar-walled waveguide according to a fourth embodiment of the present disclosure.

[0036] Figure 24 This is a diagram showing an example of the frequency response of the cylindrical waveguide according to the fourth embodiment of the present disclosure.

[0037] Figure 25 This is a diagram showing an example of electric field distribution in a pillar-walled waveguide according to the fourth embodiment of the present disclosure. DETAILED DESCRIPTION

[0038] The embodiments of the present disclosure are described in detail below, with appropriate reference to the accompanying drawings. However, overly detailed descriptions may be omitted. For example, detailed descriptions of well-known matters or repeated descriptions of substantially identical structures may be omitted. This is to avoid unnecessary redundancy in the following description and to facilitate understanding by those skilled in the art.

[0039] In addition, the drawings and the following description are provided for the purpose of enabling those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0040] In the various drawings, some elements are omitted for ease of viewing, and some elements may not be drawn to scale.

[0041] (Technical insights on which this disclosure is based)

[0042] Pillar-wall waveguides are a type of transmission line used to transmit high-frequency signals such as microwaves, millimeter waves, and terahertz waves. They consist of a dielectric layer, two conductor layers arranged above and below it, and a conductive via connecting the two layers. Compared to other transmission lines such as microstrip lines, pillar-wall waveguides offer low loss in high-frequency bands, making them widely used in high-frequency bands above the millimeter wave band.

[0043] However, like other transmission lines (such as microstrip lines), losses in cylindrical waveguides increase with increasing signal frequency. This increase in loss with increasing signal frequency is primarily due to the skin effect, which causes the surface roughness of the conductor to become non-negligible, resulting in a decrease in effective conductivity, and an increase in dielectric loss due to an increase in the dielectric loss tangent. Therefore, even in cylindrical waveguides, which offer lower losses than other transmission lines, it is desirable to minimize losses.

[0044] In addition to suppressing the loss, it is also desired to increase the degree of freedom in designing the cylindrical wall waveguide. For example, it is desired to increase the degree of freedom in designing, such as changing the thickness of the cylindrical wall waveguide.

[0045] For example, when converting from a surface-layer circuit such as a microstrip line to a pillar-walled waveguide embedded within a dielectric substrate, it is desirable to change the position of the pillar-walled waveguide in the stacking direction. Furthermore, when connecting a waveguide tube to a pillar-walled waveguide, the thickness of the connection that minimizes the loss between the waveguide tube and the pillar-walled waveguide is typically different from the thickness of the pillar-walled waveguide that minimizes the loss within the pillar-walled waveguide. Therefore, it is desirable to vary the thickness of the pillar-walled waveguide around the waveguide connection. As described above, when connecting a pillar-walled waveguide to other transmission lines such as microstrip lines and waveguide tubes, it is desirable to suppress waveguide losses while ensuring design freedom.

[0046] For example, Patent Document 1 discloses an example of improving the degree of freedom in designing a cylindrical waveguide.

[0047] Figure 1A This is a perspective view showing an example of a cylindrical wall waveguide disclosed in Patent Document 1. Figure 1B It is along Figure 1A Cross-sectional view taken along the XZ plane along the AA' line.

[0048] like Figure 1A 、 Figure 1B As shown, Patent Document 1 describes a structure formed by connecting two pillar-walled waveguides of equal thickness (e.g., the same number of layers) but with different center positions in the stacking direction. In the structure described in Patent Document 1, by connecting two pillar-walled waveguides that share a portion of a multilayer dielectric substrate, reflection loss is reduced over a wide bandwidth while enabling movement of the pillar-walled waveguides in the stacking direction. Furthermore, by connecting all conductor vias with conductors, the structure described in Patent Document 1 suppresses electromagnetic wave leakage outside the waveguides due to scattering in the coupling section.

[0049] However, in Figure 1A 、 Figure 1B In the cylindrical waveguide described in Patent Document 1, all conductor through-holes are electrically connected by conductors, increasing the surface area of ​​the conductors. Consequently, losses in the conductors (hereinafter referred to as conductor losses) increase, particularly in high-frequency bands.

[0050] Therefore, in the following embodiments, a cylindrical-walled waveguide capable of suppressing loss will be described. In addition, in the following embodiments, a cylindrical-walled waveguide capable of suppressing loss will be described in which the degree of design freedom is ensured while suppressing loss.

[0051] (Implementation Method 1)

[0052] Figure 2 This is a perspective view showing an example of the cylindrical wall waveguide 10 according to the first embodiment. Figure 2 3 and 4 show the cylindrical waveguide 10 and the X-axis, Y-axis, and Z-axis defined for the cylindrical waveguide 10 .

[0053] The cylindrical wall waveguide 10 comprises a dielectric layer 11, a first conductor layer 12, a second conductor layer 13, a conductor through hole 14, a conductor 15 and a connecting conductor 16. Figure 2 , for the convenience of illustration, the pillar-walled waveguide 10 is shown in a state where the dielectric layer 11 is seen through.

[0054] The plane along the surface where the dielectric layer 11, the first conductive layer 12, and the second conductive layer 13 are provided is defined as the XY plane. The XY plane is a plane defined by the X-axis and the Y-axis. In this case, the dielectric layer 11, the first conductive layer 12, and the second conductive layer 13 are provided along the XY plane.

[0055] The X-axis represents the axis along the extension direction of the cylindrical waveguide 10. Here, the X-axis represents the direction of travel (or transmission) of electromagnetic waves propagating through the cylindrical waveguide 10. In the following description, as an example, electromagnetic waves propagate through the cylindrical waveguide 10 in the positive X-axis direction. It should be noted that electromagnetic waves can also propagate through the cylindrical waveguide 10 in the negative X-axis direction.

[0056] The Y axis represents an axis perpendicular to the X axis. In the following description, the positive direction of the Y axis corresponds to "left" or "leftward," and the negative direction of the Y axis corresponds to "right" or "rightward."

[0057] The Z-axis represents an axis along the thickness direction of the cylindrical waveguide 10, perpendicular to the X-axis and the Y-axis. The thickness direction may also be referred to as the height direction or the stacking direction. In the following description, the positive Z-axis direction corresponds to "upward" or "above," and the negative Z-axis direction corresponds to "downward" or "below."

[0058] In addition, hereinafter, a plane defined by the X-axis and the Z-axis is referred to as an XZ plane, and a plane defined by the Y-axis and the Z-axis is referred to as a YZ plane.

[0059] Figure 3 This is a view (hereinafter referred to as a top view) of the cylindrical waveguide 10 according to the first embodiment as viewed from the positive Z-axis direction. Figure 4 It is along Figure 3 A cross-sectional view taken along the XZ plane along the AA' line (hereinafter referred to as the AA' cross-sectional view). Figure 5 It is along Figure 3 A cross-sectional view taken along the BB' line of the image processing unit (hereinafter referred to as the BB' cross-sectional view) taken along the XZ plane. Figure 6 It is along Figure 3 The cross-sectional view of the CC' line along the YZ plane (hereinafter referred to as CC' cross-sectional view). Figures 2 to 6 , the cylindrical waveguide 10 will be described. In addition, since the cylindrical waveguide 10 of the first embodiment extends in the substrate, it can be, Figures 2 to 6 The diagram shows a portion of the structure of the cylindrical waveguide 10. For example, a portion of the diagram is an enlarged view of a specific portion in another diagram. Similarly, in the drawings related to the subsequent embodiments, a portion of the diagram may be an enlarged view of a specific portion in another diagram.

[0060] The first conductor layer 12 is provided on the upper surface (the surface in the positive Z-axis direction) of the dielectric layer 11, and the second conductor layer 13 is provided on the lower surface (the surface in the negative Z-axis direction) of the dielectric layer 11. The first conductor layer 12 and the second conductor layer 13 are parallel to each other.

[0061] The dielectric layer 11 is sandwiched between the first conductive layer 12 and the second conductive layer 13. The dielectric layer 11 may be a single layer or may be composed of a plurality of dielectric layers.

[0062] Conductor vias 14 (first conductor vias) extend through the thickness of dielectric layer 11 and electrically connect first conductor layer 12 and second conductor layer 13. Multiple conductor vias 14 face each other at predetermined intervals in the Y-axis direction. Multiple conductor vias 14 are arranged along the X-axis.

[0063] The length of the conductor through-holes 14, the spacing between opposing conductor through-holes 14 in the Y-axis direction, and the spacing between adjacent conductor through-holes 14 in the X-axis direction can be determined based on the frequency (or wavelength) of the electromagnetic waves transmitted through the pillar-walled waveguide 10. For example, the spacing between adjacent conductor through-holes 14 in the X-axis direction can be less than half the wavelength of the transmitted electromagnetic waves. Furthermore, the width of the pillar-walled waveguide 10 can be, for example, at least one-fiftieth of the wavelength.

[0064] In the cylindrical-walled waveguide 10, electromagnetic waves propagate within the dielectric layer 11, which is surrounded by the first conductor layer 12, the second conductor layer 13, and the conductor through-hole 14. Hereinafter, the area where electromagnetic waves propagate is sometimes referred to as the "waveguide portion" of the cylindrical-walled waveguide 10. For example, in the cylindrical-walled waveguide 10, the first conductor layer 12 and the second conductor layer 13 correspond to the upper and lower surface walls (lower portion) of the waveguide portion, respectively, and the conductor through-hole 14 corresponds to the sidewalls of the waveguide portion.

[0065] Conductor 15 is cylindrical and serves as an example of a scatterer in the waveguide. Multiple conductors 15 may be present. By providing conductors 15, the wavelength of the electromagnetic wave transmitted within the cylindrical-walled waveguide 10 can be controlled. For example, to change (shorten) the effective wavelength within the waveguide, multiple cylindrical conductors 15 can be arranged along the transmission direction (for example, conductors 15 can be arranged in the X direction). Scatterers scatter at least a portion of the transmitted electromagnetic wave. The location of conductors 15 in the waveguide can correspond to a location that scatters at least a portion of the electromagnetic wave and / or an electrically discontinuous location.

[0066] The connecting conductor 16 (second conductor through-hole) electrically connects two or more conductor through-holes 14 present in the vicinity of the conductor 15. For example, the conductor through-hole 14a and the conductor through-hole 14b on the right side near the conductor 15 serving as a scatterer are connected by the connecting conductor 16a, and the conductor through-hole 14c and the conductor through-hole 14d on the left side near the conductor 15 are connected by the connecting conductor 16b. In this case, the conductor through-holes 14 other than the conductor through-hole 14a, the conductor through-hole 14b, the conductor through-hole 14c, and the conductor through-hole 14d may not be connected by the connecting conductor 16. In addition, the size and number of the connecting conductors 16 are not limited. In addition, the connecting conductor 16 does not have to connect all the conductor through-holes 14. For example, as Figure 2 As shown, when the conductor through-holes 14 are composed of two columns of three conductor through-holes each, the connection conductor 16 may be configured to connect two conductor through-holes 14 in each column, or may be configured to connect all the conductor through-holes 14 .

[0067] Although it is assumed here that the connecting conductor 16 electrically connects the conductor through-holes 14 that are present near the conductor 15, for example, the connecting conductor 16 may connect the conductor through-hole 14 closest to the conductor 15 and the second closest conductor through-hole 14 on the left and right sides, respectively. Alternatively, the connecting conductor 16 may connect the conductor through-hole 14 closest to the conductor 15 and at least one conductor through-hole adjacent to the closest conductor through-hole 14 on the left and right sides, respectively. Alternatively, the connecting conductor 16 may connect the conductor through-hole 14 most affected by the scattering of the conductor 15 and the conductor through-hole 14 second most affected on the left and right sides, respectively. Alternatively, the connecting conductor 16 may connect the following portions on the left and right sides, respectively, which are portions in each interval between the plurality of conductor through-holes 14 where the leakage of electromagnetic waves scattered by the conductor 15 reaches a specified level or above. This leakage of electromagnetic waves can be analyzed, for example, by computer simulation.

[0068] also, Figures 2 to 6 , an example is shown in which connecting conductor 16 connects two conductor through-holes 14 located near conductor 15. However, connecting conductor 16 may also connect three or more conductor through-holes 14. For example, connecting conductor 16 may connect three conductor through-holes 14 on the left and right sides, starting from the conductor through-hole 14 closest to conductor 15 to the third closest conductor through-hole 14. Alternatively, connecting conductor 16 may connect two or more locations on the left and right sides, each of which is located between the plurality of conductor through-holes 14 and where leakage of electromagnetic waves scattered by conductor 15 reaches a predetermined level or higher. This electromagnetic wave leakage can be analyzed, for example, through computer simulation.

[0069] also, Figures 2 to 6 , the example in which connecting conductor 16 connects two conductor through-holes 14 located near conductor 15 on the left and right sides is shown. However, connecting conductor 16 may also connect two conductor through-holes 14 located near conductor 15 on either the left or right sides. For example, when conductor 15 is more prevalent on the left side (i.e., biased toward the left), connecting conductor 16 may connect two conductor through-holes 14 located near conductor 15 on the left side, while not connecting any conductor through-holes 14 on the right side. Furthermore, the number of connected conductor through-holes 14 on the left side may be different from that on the right side.

[0070] The number and / or position of the conductor vias 14 connected by the connection conductors 16 can be determined based on at least one of the position, number, size, and shape of the conductors 15, the dimensions of the cylindrical waveguide 10, and the frequency of the electromagnetic wave. For example, when multiple conductors 15 are arranged over a wider range along the X-axis, leakage of electromagnetic waves scattered by the conductors 15 also occurs over a wider range along the X-axis. Therefore, the number of conductor vias 14 connected by the connection conductors 16 may increase.

[0071] like Figure 4 and Figure 6 As shown, the conductors 15 within the waveguide portion include a conductor 15a in contact with the first conductor layer 12 and a conductor 15b in contact with the second conductor layer 13. Alternatively, the conductors 15 may not contact the first conductor layer 12 and / or the second conductor layer 13. Furthermore, the conductors 15 may not be located at both the top and bottom of the waveguide portion, nor may the conductors 15 be uniformly distributed throughout the portion. For example, the conductors 15 may be located offset toward at least one of the top, bottom, right, or left sides of the waveguide portion.

[0072] Furthermore, the shape of conductor 15 is not limited to a cylindrical shape; it may also be a prism, pyramid, cone, or sphere. Furthermore, conductor 15 may be a shape formed by combining two or more of the following: a cylinder, a prism, a pyramid, a cone, or a sphere. Furthermore, there are no restrictions on the size and / or number of conductors 15; however, for example, the height of conductor 15 is preferably less than the height of cylindrical-walled waveguide 10.

[0073] In addition, in this first embodiment, the conductor 15 is shown as an example of a scatterer, but the present disclosure is not limited thereto. For example, the material of the scatterer may have a different dielectric constant from that of the dielectric layer 11 of the pillar-walled waveguide 10. The material of the scatterer may also be a dielectric having a different dielectric constant from that of the dielectric layer 11, or a void.

[0074] In addition, while this first embodiment illustrates an example in which the first conductor layer 12 and the second conductor layer 13 are electrically connected by individual conductor vias 14, the present disclosure is not limited thereto. For example, when the pillar-walled waveguide 10 is constructed in a multilayer substrate, the first conductor layer 12 and the second conductor layer 13 may be electrically connected by a plurality of conductor vias stacked directly above each other in each layer of the multilayer substrate. As an example, a multilayer substrate is described below, which includes three dielectric layers stacked sequentially, from the first layer to the third layer, with the first conductor layer 12 disposed above the first layer and the second conductor layer 13 disposed below the third layer. In this example, the first conductor layer 12 and the second conductor layer 13 may be electrically connected by a third conductor via in the third layer connected to the second conductor layer 13, a second conductor via stacked directly above the third conductor via in the second layer, and a first conductor via in the first layer connected to the first conductor layer 12 and stacked directly above the second conductor via.

[0075] like Figures 2 to 6 As shown, by connecting at least two conductor through-holes 14 by a connecting conductor 16, the at least two connected conductor through-holes 14 can be made to have the same potential as each other, thereby suppressing the scattering of electromagnetic waves passing through the waveguide portion due to the conductor 15 and the leakage of electromagnetic waves caused by propagation (or scattering) between the conductors 15.

[0076] As described above, there is no limitation on the size and number of the connection conductors 16. However, from the perspective of reducing conductor loss, it is preferable that the connection conductors 16 be as small as possible so as to suppress leakage of electromagnetic waves.

[0077] A larger size of connecting conductor 16 can suppress electromagnetic wave leakage caused by connecting conductor 16, but at the same time, the conductor loss of connecting conductor 16 may increase. Therefore, the size of connecting conductor 16 can be determined based on the trade-off between suppressing electromagnetic wave leakage and increasing conductor loss.

[0078] For example, the smaller the cross-sectional area of ​​conductor 15 disposed within the waveguide, the more relatively reduced the electromagnetic wave leakage caused by reflected waves in conductor 15 and / or propagation between conductors 15. Therefore, when the cross-sectional area of ​​conductor 15 is relatively small, even a small-sized connecting conductor 16 can sufficiently suppress electromagnetic wave leakage. Furthermore, in this case, by reducing the size of connecting conductor 16, the conductor loss of connecting conductor 16 can be suppressed. Therefore, the size of connecting conductor 16 can be determined based on the amount of electromagnetic wave leakage corresponding to the cross-sectional area of ​​conductor 15, the amount of electromagnetic wave leakage that connecting conductor 16 can suppress, and the conductor loss of connecting conductor 16.

[0079] For example, when the cross-sectional area of ​​conductor 15 in the YZ plane is greater than half the cross-sectional area of ​​cylindrical waveguide 10 in the YZ plane, reflected waves dominate, and electromagnetic wave leakage is relatively reduced. In this case, the conductor loss of connecting conductor 16 may have a greater impact than the electromagnetic wave leakage suppressed by connecting conductor 16. Therefore, whether to connect conductor via 14 via connecting conductor 16 can be determined based on the cross-sectional area of ​​conductor 15 in the YZ plane and the cross-sectional area of ​​cylindrical waveguide 10 in the YZ plane. For example, when the cross-sectional area of ​​conductor 15 in the YZ plane is less than or equal to half the cross-sectional area of ​​cylindrical waveguide 10 in the YZ plane, connecting conductor via 14 via connecting conductor 16 can be used to suppress electromagnetic wave scattering and leakage. When there are multiple conductors 15, "cross-sectional area of ​​conductor 15 in the YZ plane" can be replaced with the total cross-sectional area of ​​the multiple conductors 15 in the YZ plane.

[0080] Furthermore, the greater the width of conductor 15 in the YZ plane, the greater the reflected wave, and the relatively reduced electromagnetic wave leakage. Therefore, the greater the width of conductor 15 in the YZ plane, the more likely that the electromagnetic wave leakage suppressed by connecting conductor 16 will be less than the impact of conductor loss in connecting conductor 16. Therefore, whether to connect conductor via 14 via connecting conductor 16 can be determined based on the width of conductor 15 in the YZ plane. For example, when the width of conductor 15 in the YZ plane is less than or equal to half the width of column-walled waveguide 10 in the YZ plane, connecting conductor via 14 via connecting conductor 16 can be used to suppress electromagnetic wave scattering and leakage. When there are multiple conductors 15, "the width of conductor 15 in the YZ plane" can be replaced with the total length of the widths of the multiple conductors 15 in the YZ plane.

[0081] Next, let’s explain about Figures 2 to 6 Computer simulation results for suppressing electromagnetic wave leakage in the cylindrical waveguide 10 are shown. In this first embodiment, a simulation was performed to calculate the frequency response of the bandpass characteristics of the cylindrical waveguide 10 using a three-dimensional electromagnetic field analysis using the finite integration method. As an example, the port for input and output from the end of the cylindrical waveguide 10 in the negative X-axis direction is designated as Port 1, and the port for input and output from the end in the positive X-axis direction is designated as Port 2. Furthermore, in the second embodiment and subsequent embodiments described below, the same electromagnetic field analysis as in this first embodiment is also performed.

[0082] In the three-dimensional electromagnetic field analysis using the finite integration method in this first embodiment, as an example, analysis was conducted for a case where the thickness of the dielectric layer 11 of the cylindrical waveguide 10 was set to 220 μm, the thickness of the first and second conductor layers 12 and 13 sandwiching the dielectric layer 11 was set to 20 μm, the diameter of the conductor through-holes 14 was set to 60 μm, the spacing (pitch) between the conductor through-holes 14 was set to 170 μm, and the length of the cylindrical waveguide 10 was set to 2.5 mm. Furthermore, the shape of the conductor 15 was set to a cylindrical shape, and the height of the conductor 15 was set to 50 μm. It should be noted that the above parameters of the cylindrical waveguide 10 used in the analysis are merely examples and the present disclosure is not limited thereto.

[0083] Figure 7 This is a diagram showing an example of the frequency response of the cylindrical waveguide 10 according to the first embodiment. Figure 7 The frequency response of the bandpass characteristic of the cylindrical wall waveguide 10 at around 300 GHz is shown. Figure 7 The horizontal axis represents the frequency axis, and the vertical axis represents the decibel value of the absolute value of S21, an S parameter representing the bandpass characteristic from port 1 to port 2. Figure 7 The larger the value on the vertical axis, the larger the size of the electromagnetic wave passing through.

[0084] Figure 7FIG. 1 shows the frequency response of the bandpass characteristics of Comparative Example 1 and Comparative Example 2 as comparative examples. Comparative Example 1 is a case where the connecting conductor 16 is removed from the cylindrical waveguide 10 ( Figure 7 Comparative Example 2 is a structure in which all conductor through-holes 14 in a cylindrical-walled waveguide 10 are connected by connecting conductors 16. It should be noted that, except for the absence of connecting conductors 16, the parameters of each structure in Comparative Example 1 can be the same as those of the cylindrical-walled waveguide 10 described above. Furthermore, except for the fact that all conductor through-holes 14 are connected by connecting conductors, the parameters of each structure in Comparative Example 2 can be the same as those of the cylindrical-walled waveguide 10 described above.

[0085] like Figure 7 As shown, within the illustrated frequency range, the frequency response of the cylindrical-walled waveguide 10 exhibits a wider bandpass characteristic than that of Comparative Examples 1 and 2. Thus, by providing the cylindrical-walled waveguide 10 with a structure in which the conductor through-holes 14 near the conductor 15 are electrically connected by the connecting conductor 16, it is possible to simultaneously suppress electromagnetic wave leakage and reduce conductor loss, thereby improving the bandpass characteristic over a wide frequency band.

[0086] As described above, the connection of the conductor vias 14 with the connection conductors 16 reduces the loss because the connection conductors 16 suppress the leakage of electromagnetic waves to the outside of the waveguide. Next, the effect of suppressing the leakage of electromagnetic waves to the outside of the waveguide will be described using the electric field distribution.

[0087] Figure 8 1 is a diagram showing an example of electric field distribution in the pillar-walled waveguide 10 according to the first embodiment. Figure 8 The electric field distribution in the cylindrical-walled waveguide 10 and the electric field distribution in the structure of Comparative Example 1 are shown. Figure 8 The electric field distribution shown shows the electric field intensity in the horizontal plane (XY plane) of the waveguide using shades.

[0088] By comparison Figure 8 From the electric field distributions of the cylindrical-walled waveguide 10 and the comparative example 1, it is clear that the leakage of electromagnetic waves to the outside of the waveguide can be suppressed by connecting the conductor through-holes 14 with the connection conductors 16.

[0089] As described above, the pillar-walled waveguide 10 of the first embodiment includes a dielectric layer 11, a first conductor layer 12 stacked in the direction in which the dielectric layer 11 is stacked, a second conductor layer 13 stacked at a position different from the first conductor layer in the direction in which the dielectric layer is stacked, and a plurality of conductor through-holes 14 electrically connecting the first conductor layer 12 and the second conductor layer 13. Furthermore, the pillar-walled waveguide 10 includes a connecting conductor 16 electrically connecting two or more conductor through-holes 14 provided near a conductor 15 located in the waveguide portion through which electromagnetic waves pass, which is surrounded by the first conductor layer 12, the second conductor layer 13, and the plurality of conductor through-holes 14. The conductor 15 is an example of a scatterer, an example of a specific location where electromagnetic waves are scattered.

[0090] According to the column-walled waveguide 10 of the first embodiment, by connecting the conductor through-holes 14 near the scatterer, i.e., the conductor 15, with the connecting conductor 16, at least two connected conductor through-holes 14 are made to have the same potential as each other, thereby suppressing the scattering of electromagnetic waves passing through the waveguide caused by the conductor 15 and the leakage of electromagnetic waves caused by propagation between the conductors 15, thereby suppressing losses.

[0091] (Implementation Method 2)

[0092] Figure 9 This is a perspective view showing an example of the cylindrical wall waveguide 20 according to the second embodiment. Figure 9 , the columnar waveguide 20 and the X-axis, Y-axis, and Z-axis set for the columnar waveguide 20 are shown. Figure 9 In FIG. 1 , for convenience of illustration, the pillar-walled waveguide 20 is shown in a state where the dielectric layer 11 is seen through.

[0093] The X-axis, Y-axis, and Z-axis are the same as those described in the first embodiment, and thus their description is omitted.

[0094] Figure 10 1 is a plan view showing the cylindrical wall waveguide 20 according to the second embodiment. Figure 11 It is along Figure 10 AA' cross-sectional view taken along the XZ plane. Figure 12 It is along Figure 10 BB' cross-sectional view taken along the XZ plane. Figure 13 It is along Figure 10 The CC' section view of the C-C' line along the YZ plane. Figures 9 to 13 , the column-wall waveguide 20 will be described.

[0095] In addition, Figures 9 to 13 In the embodiment 1, for the cylindrical waveguide 10 (for example, Figures 2 to 6 ) are identical in structure to those of the present invention, and the same reference numerals are used and the description thereof is omitted. Figures 9 to 13 The boundary P shown in represents a planar boundary along the YZ plane.

[0096] The first conductor layer 12 is disposed on the upper surface of the dielectric layer 11, and the second conductor layer 13 is disposed on the lower surface of the dielectric layer 11. The first conductor layer 12 and the second conductor layer 13 are parallel to each other.

[0097] The dielectric layer 11 is sandwiched between the first conductive layer 12 and the second conductive layer 13. The dielectric layer 11 may be a single layer or may be composed of a plurality of dielectric layers.

[0098] In the thickness direction, a third conductor layer 21 and a fourth conductor layer 22 are provided within the dielectric layer 11, between the first conductor layer 12 and the second conductor layer 13. The third conductor layer 21 is provided above the fourth conductor layer 22 and extends from the boundary P in the positive direction of the X-axis. The fourth conductor layer 22 is provided below the third conductor layer 21 and extends from the boundary P in the negative direction of the X-axis.

[0099] In addition, Figures 9 to 13 In the illustrated cylindrical-walled waveguide 20 , the third conductor layer 21 and the fourth conductor layer 22 do not overlap in a plan view as viewed from the positive Z-axis direction.

[0100] Conductor vias 24 extend within dielectric layer 11 along the thickness direction, electrically connecting the two conductor layers. Multiple conductor vias 24 are spaced apart and face each other in the Y-axis direction. Furthermore, multiple conductor vias 24 are arranged along the X-axis. Conductor vias 24 include conductor vias 24a located in an area closer to the positive X-axis than boundary P, and conductor vias 24b located in an area closer to the negative X-axis than boundary P. Conductor vias 24a electrically connect the second conductor layer 13 and the third conductor layer 21. Conductor vias 24b electrically connect the first conductor layer 12 and the fourth conductor layer 22.

[0101] Conductor vias 23 extend through the dielectric layer 11 along its thickness, electrically connecting the two conductor layers. Conductor vias 23 include conductor vias 23a located in a region closer to the positive X-axis than boundary P, and conductor vias 23b located in a region closer to the negative X-axis than boundary P. Conductor vias 23a electrically connect the first conductor layer 12 and the third conductor layer 21. Conductor vias 23b electrically connect the second conductor layer 13 and the fourth conductor layer 22.

[0102] Conductor through-holes 23a and conductor through-holes 23b are arranged along the Y-axis and the X-axis, respectively. Of the conductor through-holes 23a, those arranged along the X-axis may be located directly above conductor through-holes 24a. Alternatively, conductor through-holes 23a arranged along the X-axis may be integrally formed with conductor through-holes 24a. In this case, conductor through-holes 24a may pass through third conductor layer 21 to electrically connect first conductor layer 12 and second conductor layer 13. Similarly, conductor through-holes 23b arranged along the X-axis may be integrally formed with conductor through-holes 24b.

[0103] exist Figure 11 In the region shown as being closer to the negative direction of the X axis than the boundary P, the electromagnetic wave propagates within the range of the dielectric layer 11 surrounded by the first conductor layer 12, the fourth conductor layer 22, and the conductor through hole 24b. Figure 11 In the region shown closer to the positive direction of the X axis than the boundary P, electromagnetic waves propagate within the range of the dielectric layer 11 surrounded by the second conductor layer 13 , the third conductor layer 21 , and the conductor through-hole 24 a .

[0104] so, Figures 9 to 13 The cylindrical wall waveguide 20 shown has a structure formed by connecting two cylindrical wall waveguides.

[0105] As an example, Figure 11 The region closer to the positive direction of the X axis than the boundary P is recorded as the cylindrical wall waveguide 20-1, and the region closer to the negative direction of the X axis than the boundary P is recorded as the cylindrical wall waveguide 20-2. Figure 11 As shown, the center position of the waveguide portion of the cylindrical wall waveguide 20-1 in the thickness direction is indicated by line Q, and the center position of the waveguide portion of the cylindrical wall waveguide 20-2 in the thickness direction is indicated by line R. Line Q and line R are different from each other in the thickness direction of the waveguide portion.

[0106] As mentioned above, Figures 9 to 13 The illustrated cylindrical waveguide 20 has a structure in which a cylindrical waveguide 20 - 1 and a cylindrical waveguide 20 - 2 , which have different waveguide portion thicknesses and different center positions in the thickness direction of the waveguide portion, are connected at a boundary P.

[0107] Electromagnetic wave leakage in the cylindrical waveguide 20 occurs at locations where the thickness of the waveguide portion or the center position of the waveguide portion varies. These locations are examples of scatterers. Furthermore, these locations can also correspond to locations that scatter at least a portion of the electromagnetic wave and / or locations that are electrically discontinuous.

[0108] For example, in Figures 9 to 13In the example shown in FIG. 1 , the vicinity of boundary P is where the thickness and center position of the waveguide section change. In this case, electromagnetic wave leakage from the cylindrical-walled waveguide 20 is caused by electromagnetic wave scattering near boundary P by the third and fourth conductor layers 21 and 22, and by electromagnetic wave propagation along the third and fourth conductor layers 21 and 22.

[0109] The connecting conductor 26 connects the conductor vias 24 near the ends of the third conductor layer 21 and the fourth conductor layer 22 near the boundary P. As an example, the conductor via 24 a - 1 and the conductor via 24 b - 1 on the right side near the boundary P are connected by the connecting conductor 26 a , and the conductor via 24 a - 2 and the conductor via 24 b - 2 on the left side near the boundary P are connected by the connecting conductor 26 b .

[0110] It should be noted that while this second embodiment illustrates an example in which the waveguide portions of two cylindrical waveguides have different thicknesses and different center positions, the present disclosure is not limited to this. For example, even when the waveguide portions of two cylindrical waveguides have different thicknesses or different center positions, loss can be suppressed by connecting conductor vias located near a boundary where thickness changes or a boundary where center position changes, similar to the case of cylindrical waveguide 20. For example, in this case, the boundary where thickness changes or the boundary where center position changes can be an example of a scatterer. The boundary where thickness changes or the boundary where center position changes can be a location where at least a portion of electromagnetic waves is scattered and / or a location where there is electrical discontinuity.

[0111] Furthermore, in the cylindrical-walled waveguide 20, in order to suppress electromagnetic wave leakage between the first conductor layer 12 and the third conductor layer 21, and between the second conductor layer 13 and the fourth conductor layer 22, a conductor through-hole 23a is provided between the first conductor layer 12 and the third conductor layer 21, and a conductor through-hole 23b is provided between the second conductor layer 13 and the fourth conductor layer 22.

[0112] It should be noted that there is no limitation on the location of the conductor through-hole 23. For example, the location of the conductor through-hole 23 may be set so that the distance from the boundary P to the conductor through-hole 23a and / or the distance from the boundary P to the conductor through-hole 23b is a distance that reduces the reflected wave near the boundary P. For example, the location of the conductor through-hole 23a and / or the conductor through-hole 23b may be set so that the reflected wave near the boundary P is minimized.

[0113] Furthermore, although the example in which the conductor via 23a electrically connects the first conductor layer 12 and the third conductor layer 21, and the example in which the conductor via 23b electrically connects the second conductor layer 13 and the fourth conductor layer 22 are shown, the present disclosure is not limited thereto. For example, when the pillar-walled waveguide 20 is formed in a multilayer substrate, a plurality of conductor vias 23 stacked directly above each other in each layer of the multilayer substrate may electrically connect the first conductor layer 12 and the third conductor layer 21, or the second conductor layer 13 and the fourth conductor layer 22. For example, in this second embodiment, the structure in which the conductor via connects two conductor layers may be a structure in which a single conductor via directly connects the two conductor layers, or a structure in which a plurality of conductor vias stacked directly above each other in each layer of the multilayer substrate connects the two conductor layers.

[0114] Next, let’s explain about Figures 9 to 13 The computer simulation results of the electromagnetic wave leakage suppression in the cylindrical wall waveguide 20 are shown. It should be noted that the simulation method used in the second embodiment is the same as that used in the first embodiment.

[0115] In the three-dimensional electromagnetic field analysis using the finite integration method in this second embodiment, as an example, analysis was conducted for a case where the thickness of the dielectric layer 11 of the cylindrical waveguide 20 was set to 220 μm, the thicknesses of the first conductor layer 12, the second conductor layer 13, the third conductor layer 21, and the fourth conductor layer 22 were set to 20 μm, the diameters of the conductor through-holes 14 and 23 were set to 60 μm, the interval (pitch) between the conductor through-holes 14 was set to 170 μm, and the length of the cylindrical waveguide 20 was set to 2.5 mm. It should be noted that the above parameters of the cylindrical waveguide 20 used in the analysis are merely examples and the present disclosure is not limited thereto.

[0116] Figure 14 This is a diagram showing an example of the frequency response of the cylindrical waveguide 20 according to the second embodiment. Figure 14 The frequency response of the bandpass characteristic of the cylindrical wall waveguide 20 at around 300 GHz is shown. Figure 14 The horizontal axis represents the frequency axis, and the vertical axis represents the decibel value of the absolute value of S21, an S parameter representing the bandpass characteristic. Figure 14 The larger the value on the vertical axis, the larger the size of the electromagnetic wave passing through.

[0117] Figure 14 FIG. 3 shows the frequency response of the bandpass characteristic of Comparative Example 3 as a comparative example. Comparative Example 3 is a case where the connecting conductor 26 is removed from the cylindrical waveguide 20 ( Figure 14 It should be noted that, except that the connection conductor 26 is not provided, the parameters of each structure of Comparative Example 3 can be the same as those of the above-mentioned cylindrical waveguide 20.

[0118] like Figure 14As shown, within the illustrated frequency range, the frequency response of the cylindrical-walled waveguide 20 exhibits a wider bandpass characteristic than that of Comparative Example 3. Thus, by providing the cylindrical-walled waveguide 20 with a structure in which the conductor through-holes 24 near the boundary P are electrically connected by the connecting conductor 26, it is possible to simultaneously suppress electromagnetic wave leakage and reduce conductor loss, thereby improving the bandpass characteristic over a wide frequency band.

[0119] As described above, the connection of the conductor vias 24 with the connection conductors 26 reduces the loss because the connection conductors 26 suppress the leakage of electromagnetic waves to the outside of the waveguide. Next, the effect of suppressing the leakage of electromagnetic waves to the outside of the waveguide will be described using the electric field distribution.

[0120] Figure 15 1 is a diagram showing an example of electric field distribution in the pillar-walled waveguide 20 according to the second embodiment. Figure 15 The electric field distribution in the cylindrical waveguide 20 and the electric field distribution in the structure of Comparative Example 3 are shown. Figure 15 The electric field distribution shown shows the electric field intensity in the horizontal plane (XY plane) of the waveguide using shades.

[0121] By comparison Figure 15 From the electric field distributions of the cylindrical-walled waveguide 20 and the structure of Comparative Example 3, it can be clearly seen that the leakage of electromagnetic waves to the outside of the waveguide can be suppressed by connecting the conductor through-holes 24 with the connecting conductors 26.

[0122] Furthermore, conventionally, a larger pitch increases electromagnetic field leakage between conductor vias 24, thus increasing the leakage suppression effect of connection conductor 26. By suppressing electromagnetic wave leakage with connection conductor 26, the bandpass characteristic can be improved over a wide frequency range.

[0123] As described above, the pillar-walled waveguide 20 of the second embodiment includes a dielectric layer 11, and a first conductor layer 12, a second conductor layer 13, a third conductor layer 21, and a fourth conductor layer 22 stacked on the dielectric layer 11. The first conductor layer 12, the second conductor layer 13, the third conductor layer 21, and the fourth conductor layer 22 are stacked at different positions in the stacking direction. Furthermore, the pillar-walled waveguide 20 includes a connecting conductor 26 that electrically connects the conductive vias 24 provided near the boundary between the pillar-walled waveguides 20-1 and 20-2. The pillar-walled waveguide 20-1 is a pillar-walled waveguide surrounded by the second conductor layer 13, the third conductor layer 21, and the conductive vias 24a, through which electromagnetic waves pass. The pillar-walled waveguide 20-2 is a pillar-walled waveguide surrounded by the first conductor layer 12, the fourth conductor layer 22, and the conductive vias 24b, through which electromagnetic waves pass. The boundary between the cylindrical-walled waveguide 20 - 1 and the cylindrical-walled waveguide 20 - 2 is an example of a scatterer, and is an example of a specific location where electromagnetic waves are scattered.

[0124] According to the column-wall waveguide 20 of the second embodiment, the conductor through-holes 24 near the boundary P corresponding to the scatterer are connected by the connecting conductor 26 so that at least two connected conductor through-holes 24 are at the same potential with each other, thereby suppressing the scattering of electromagnetic waves and the leakage of electromagnetic waves near the boundary P and suppressing the loss.

[0125] (Implementation Method 3)

[0126] Figure 16 This is a perspective view showing an example of a cylindrical wall waveguide 30 according to the third embodiment. Figure 16 , the columnar wall waveguide 30 and the X-axis, Y-axis, and Z-axis set for the columnar wall waveguide 30 are shown. Figure 16 In FIG. 1 , for convenience of illustration, the pillar-walled waveguide 30 is shown in a state where the dielectric layer 11 is seen through.

[0127] The X-axis, Y-axis, and Z-axis are the same as those described in the first embodiment, and thus their description is omitted.

[0128] Figure 17 1 is a plan view showing a cylindrical wall waveguide 30 according to the third embodiment. Figure 18 It is along Figure 17 AA' cross-sectional view taken along the XZ plane. Figure 19 It is along Figure 17 BB' cross-sectional view taken along the XZ plane. Figure 20 It is along Figure 17 The CC' section view of the C-C' line along the YZ plane. Figures 16 to 20 , the column-wall waveguide 30 will be described.

[0129] In addition, Figures 16 to 20 In the embodiment 1, for the cylindrical waveguide 10 (for example, Figures 2 to 6 ) are identical in structure to those of the present invention, and the same reference numerals are used and the description thereof is omitted. Figures 16 to 20 The boundary P shown in represents a planar boundary along the YZ plane.

[0130] The first conductive layer 12 is disposed on the upper surface of the dielectric layer 11, and the second conductive layer 13 is disposed on the lower surface of the dielectric layer 11. The first conductive layer 12 and the second conductive layer 13 are parallel to each other.

[0131] The dielectric layer 11 is sandwiched between the first conductive layer 12 and the second conductive layer 13. The dielectric layer 11 may be a single layer or may be composed of a plurality of dielectric layers.

[0132] In the thickness direction, the third conductor layer 31 is provided inside the dielectric layer 11 between the first conductor layer 12 and the second conductor layer 13. The third conductor layer 31 extends from the boundary P in the negative direction of the X axis.

[0133] Conductor vias 34 extend within dielectric layer 11 along the thickness direction, electrically connecting the two conductor layers. Multiple conductor vias 34 are positioned opposite each other at predetermined intervals in the Y-axis direction. Furthermore, multiple conductor vias 34 are arranged along the X-axis. Conductor vias 34 include conductor vias 34a located in an area closer to the positive X-axis than boundary P, and conductor vias 34b located in an area closer to the negative X-axis than boundary P. Conductor vias 34a electrically connect the first conductor layer 12 and the second conductor layer 13. Conductor vias 34b electrically connect the first conductor layer 12 and the third conductor layer 31.

[0134] Conductor vias 33 extend along the thickness direction within dielectric layer 11, electrically connecting second conductor layer 13 and third conductor layer 31. Conductor vias 33 are arranged along the Y-axis and the X-axis. Those arranged along the X-axis may be positioned directly below conductor via 34b. Alternatively, those arranged along the X-axis may be integrally formed with conductor via 34b. In this case, conductor via 34b can pass through third conductor layer 31 and electrically connect first conductor layer 12 and second conductor layer 13.

[0135] exist Figure 18 In the region shown as being closer to the negative direction of the X axis than the boundary P, the electromagnetic wave propagates within the range of the dielectric layer 11 surrounded by the first conductor layer 12, the third conductor layer 31 and the conductor through hole 34b. Figure 18 In the region closer to the positive direction of the X axis than the boundary P shown, the electromagnetic wave propagates within the range of the dielectric layer 11 surrounded by the first conductor layer 12 , the second conductor layer 13 , and the conductor through-hole 34 a .

[0136] so, Figures 16 to 20 The illustrated cylindrical-walled waveguide 30 has a structure in which two cylindrical-walled waveguides are connected. In addition, the cylindrical-walled waveguide 30 has a common first conductor layer 12 corresponding to the upper surface.

[0137] As an example, Figure 18 The region closer to the positive direction of the X-axis than the boundary P is recorded as the cylindrical wall waveguide 30-1, and the region closer to the negative direction of the X-axis than the boundary P is recorded as the cylindrical wall waveguide 30-2. Figure 18 As shown, the center position of the waveguide portion of the cylindrical wall waveguide 30-1 in the thickness direction is indicated by line Q, and the center position of the waveguide portion of the cylindrical wall waveguide 30-2 in the thickness direction is indicated by line R. Lines Q and R are different from each other in the thickness direction of the waveguide portion.

[0138] As mentioned above, Figures 16 to 20The illustrated cylindrical waveguide 20 has a structure in which a cylindrical waveguide 30 - 1 and a cylindrical waveguide 30 - 2 , which have different waveguide portion thicknesses and different center positions in the thickness direction of the waveguide portion, are connected at a boundary P.

[0139] Electromagnetic wave leakage in the cylindrical waveguide 30 occurs at locations where the thickness of the waveguide portion or the center position of the waveguide portion varies. These locations are examples of scatterers. Furthermore, these locations can also correspond to locations that scatter at least a portion of the electromagnetic wave and / or are electrically discontinuous.

[0140] For example, in Figures 16 to 20 In the example, the area near boundary P corresponds to the location where the thickness and center position of the waveguide section change. In this case, electromagnetic wave leakage from the cylindrical-walled waveguide 30 is caused by electromagnetic wave scattering by the third conductive layer 31 near boundary P and electromagnetic wave propagation along the third conductive layer 31.

[0141] The connecting conductor 36 connects the conductor vias 34 near the end of the third conductor layer 31 near the boundary P. As an example, the conductor via 34 a - 1 and the conductor via 34 b - 1 on the right side near the boundary P are connected by the connecting conductor 36 a , and the conductor via 34 a - 2 and the conductor via 34 b - 2 on the left side near the boundary P are connected by the connecting conductor 36 b .

[0142] Furthermore, in the cylindrical-walled waveguide 30 , a conductor through-hole 33 is provided between the second conductor layer 13 and the third conductor layer 31 in order to suppress leakage of electromagnetic waves between the second conductor layer 13 and the third conductor layer 31 .

[0143] Next, let’s explain about Figures 16 to 20 The computer simulation results of the electromagnetic wave leakage suppression in the cylindrical wall waveguide 30 are shown. It should be noted that the simulation method used in the third embodiment is the same as that used in the first embodiment.

[0144] In the three-dimensional electromagnetic field analysis using the finite integration method in this third embodiment, as an example, analysis was conducted for a case where the thickness of the dielectric layer 11 of the cylindrical waveguide 30 was set to 220 μm, the thicknesses of the first conductor layer 12, the second conductor layer 13, and the third conductor layer 31 were set to 20 μm, the diameters of the conductor through-holes 14 and 33 were set to 60 μm, the interval (pitch) between the conductor through-holes 34 was set to 170 μm, and the length of the cylindrical waveguide 30 was set to 2.5 mm. It should be noted that the above parameters of the cylindrical waveguide 30 used in the analysis are merely examples and the present disclosure is not limited thereto.

[0145] Figure 21This is a diagram showing an example of the frequency response of the cylindrical wall waveguide 30 according to the third embodiment. Figure 21 The frequency response of the bandpass characteristic of the cylindrical wall waveguide 30 at around 300 GHz is shown. Figure 21 The horizontal axis represents the frequency axis, and the vertical axis represents the decibel value of the absolute value of S21, an S parameter representing the bandpass characteristic. Figure 21 The larger the value on the vertical axis, the larger the size of the electromagnetic wave passing through.

[0146] Figure 21 FIG4 shows the frequency response of the bandpass characteristic of Comparative Example 4 as a comparative example. Comparative Example 4 is a case where the connecting conductor 36 ( Figure 21 It should be noted that, except that the connection conductor 36 is not provided, the parameters of each structure of Comparative Example 4 can be the same as those of the above-mentioned cylindrical wall waveguide 30.

[0147] like Figure 21 As shown, within the illustrated frequency range, the frequency response of the cylindrical-walled waveguide 30 exhibits a wider bandpass characteristic than that of Comparative Example 4. Thus, by providing the cylindrical-walled waveguide 30 with a structure in which the conductor through-holes 34 near the boundary P are electrically connected by the connecting conductor 36, it is possible to simultaneously suppress electromagnetic wave leakage and reduce conductor loss, thereby improving the bandpass characteristic over a wide frequency band.

[0148] As described above, the connection of the conductor vias 34 with the connection conductors 36 reduces the loss because the connection conductors 36 suppress the leakage of electromagnetic waves to the outside of the waveguide. Next, the effect of suppressing the leakage of electromagnetic waves to the outside of the waveguide will be described using the electric field distribution.

[0149] Figure 22 This is a diagram showing an example of electric field distribution in the pillar-walled waveguide 30 according to the third embodiment. Figure 22 The electric field distribution in the cylindrical waveguide 30 and the electric field distribution in the structure of Comparative Example 4 are shown. Figure 22 The electric field distribution shown shows the electric field intensity in the horizontal plane (XY plane) of the waveguide using shades.

[0150] By comparison Figure 22 From the electric field distributions of the cylindrical wall waveguide 30 and the comparative example 4, it is clear that the leakage of electromagnetic waves to the outside of the waveguide can be suppressed by connecting the conductor through-holes 34 with the connection conductors 36.

[0151] As described above, the pillar-walled waveguide 30 of the third embodiment includes a dielectric layer 11, a first conductor layer 12, a second conductor layer 13, and a third conductor layer 31 stacked on the dielectric layer 11. The second conductor layer 13 and the third conductor layer 31 are stacked at different positions in the stacking direction. Furthermore, the pillar-walled waveguide 30 includes a connecting conductor 36 that electrically connects a conductor through-hole 34 provided near the boundary P between the pillar-walled waveguides 30-1 and 30-2. The pillar-walled waveguide 30-1 is a pillar-walled waveguide that allows electromagnetic waves to pass through, surrounded by the first conductor layer 12, the second conductor layer 13, and the conductor through-hole 34a. The pillar-walled waveguide 30-2 is a pillar-walled waveguide that allows electromagnetic waves to pass through, surrounded by the first conductor layer 12, the third conductor layer 31, and the conductor through-hole 34b. The boundary P between the pillar-walled waveguides 30-1 and 30-2 is an example of a scatterer, an example of a specific location where electromagnetic waves are scattered.

[0152] According to the column-wall waveguide 30 of the third embodiment, the conductor through-holes 34 near the boundary P corresponding to the scatterer are connected by the connecting conductor 36 so that at least two connected conductor through-holes 34 are at the same potential with each other, thereby suppressing the scattering of electromagnetic waves and the leakage of electromagnetic waves near the boundary P and suppressing the loss.

[0153] (Implementation Method 4)

[0154] Figure 23 This is a perspective view showing an example of a cylindrical wall waveguide 40 according to the fourth embodiment. Figure 23 , the columnar wall waveguide 40 and the X-axis, Y-axis, and Z-axis set for the columnar wall waveguide 40 are shown. Figure 23 In FIG. 4 , for the sake of convenience, the cylindrical waveguide 40 is shown with the dielectric layer 11 being transparent. Figure 23 In the present invention, the same structures as those of the cylindrical wall waveguide 10 shown in the first embodiment are denoted by the same reference numerals and their description is omitted.

[0155] The X-axis, Y-axis, and Z-axis are the same as those described in the first embodiment, and thus their description is omitted.

[0156] Figure 23 The cylindrical-walled waveguide 40 shown has a structure in which the connection conductor 16 and the conductor through-holes 14 connected by the connection conductor 16 are replaced with conductor through-holes 41 in the cylindrical-walled waveguide 10 shown in the first embodiment.

[0157] Conductor via 41 has its long side in the signal transmission direction (positive or negative X-axis direction). Similar to connection conductor 16 in Embodiment 1, conductor via 41 is provided near conductor 15, which serves as a scatterer. This structure suppresses scattering of electromagnetic waves passing through the waveguide portion by conductor 15 and leakage of electromagnetic waves caused by propagation between conductors 15.

[0158] In addition, Figure 23 , the first conductor layer 12 and the second conductor layer 13 are directly electrically connected by the conductor through-hole 41, but the present disclosure is not limited thereto. For example, when the pillar-walled waveguide 40 is formed in a multilayer substrate, the first conductor layer 12 and the second conductor layer 13 may be electrically connected by a plurality of conductor through-holes stacked directly above each other in each layer of the multilayer substrate, each having a long side in the positive or negative direction of the X-axis.

[0159] Next, let’s explain about Figure 23 The computer simulation results of the electromagnetic wave leakage suppression in the cylindrical wall waveguide 40 are shown. It should be noted that the simulation method used in the fourth embodiment is the same as that used in the first embodiment.

[0160] In the three-dimensional electromagnetic field analysis using the finite integration method in this fourth embodiment, as an example, analysis was conducted for a case where the thickness of the dielectric layer 11 of the cylindrical waveguide 40 was set to 220 μm, the thicknesses of the first and second conductor layers 12 and 13 were set to 20 μm, the diameter of the conductor through-holes 14 was set to 60 μm, the interval (pitch) between the conductor through-holes 14 was set to 170 μm, and the length of the cylindrical waveguide 40 was set to 2.5 mm. It should be noted that the above parameters of the cylindrical waveguide 40 used in the analysis are merely examples and the present disclosure is not limited thereto.

[0161] Figure 24 This is a diagram showing an example of the frequency response of the cylindrical wall waveguide 40 according to the fourth embodiment. Figure 24 The frequency response of the bandpass characteristic of the cylindrical wall waveguide 40 at around 300 GHz is shown. Figure 24 The horizontal axis represents the frequency axis, and the vertical axis represents the decibel value of the absolute value of S21, an S parameter representing the bandpass characteristic. Figure 24 The larger the value on the vertical axis, the larger the size of the electromagnetic wave passing through.

[0162] exist Figure 24 , as a comparative example, the frequency response of the bandpass characteristic of Comparative Example 1 used in Embodiment 1 is shown.

[0163] like Figure 24 As shown, within the illustrated frequency range, the frequency response of the cylindrical-walled waveguide 40 exhibits a wider bandpass characteristic than that of Comparative Example 1. Thus, by providing the cylindrical-walled waveguide 40 with a structure in which the conductor through-holes 14 near the boundary P are electrically connected by the connecting conductor 16, it is possible to simultaneously suppress electromagnetic wave leakage and reduce conductor loss, thereby improving the bandpass characteristic over a wide frequency band.

[0164] As described above, the conductor through-hole 41 reduces the loss because the conductor through-hole 41 suppresses the leakage of electromagnetic waves to the outside of the waveguide portion. Next, the effect of suppressing the leakage of electromagnetic waves to the outside of the waveguide will be described using the electric field distribution.

[0165] Figure 25 This is a diagram showing an example of electric field distribution in the pillar-walled waveguide 40 according to the fourth embodiment. Figure 25 The electric field distribution in the cylindrical-walled waveguide 40 and the electric field distribution in the structure of Comparative Example 1 are shown. Figure 15 The electric field distribution shown shows the electric field intensity in the horizontal plane (XY plane) of the waveguide using shades.

[0166] By comparison Figure 25 From the electric field distributions of the cylindrical wall waveguide 40 and the structure of Comparative Example 1, it can be clearly seen that the conductive through-hole 41 can suppress the leakage of electromagnetic waves to the outside of the waveguide.

[0167] As described above, the cylindrical-walled waveguide 40 of the fourth embodiment has a structure in which the connecting conductor 16 and the conductor vias 14 connected by the connecting conductor 16 are replaced with conductor vias 41 in the cylindrical-walled waveguide 10 shown in the first embodiment. With this structure, since the conductor vias 41 near the conductor 15, which serves as a scatterer, have long sides in the direction of electromagnetic wave propagation, similar to the connecting conductor 16 connecting two conductor vias 14 in the first embodiment, scattering of electromagnetic waves passing through the waveguide portion by the conductor 15 and leakage of electromagnetic waves due to propagation between the conductors 15 can be suppressed, thereby reducing losses.

[0168] Furthermore, according to the pillar-walled waveguide 40 of the fourth embodiment, the conductor through-hole 41, like the other conductor through-holes 14, is structured to pass through the dielectric layer 11 and connect the first conductor layer 12 and the second conductor layer 13. This simplifies the manufacturing process of the pillar-walled waveguide, thereby reducing the manufacturing cost.

[0169] Furthermore, according to the cylindrical-walled waveguide 40 of the fourth embodiment, since the conductor through-hole 41 blocks the space between the first conductor layer 12 and the second conductor layer 13 , leakage of electromagnetic waves can be suppressed more effectively.

[0170] Furthermore, while the above embodiments illustrate examples in which two conductor layers are connected by a single conductor via, the present disclosure is not limited thereto. When a pillar-walled waveguide is formed in a multilayer substrate, the two conductor layers may be electrically connected by a plurality of conductor vias stacked directly above each other in each layer of the multilayer substrate.

[0171] In addition, in the above embodiments, examples are shown in which the first conductor layer 12 and the second conductor layer 13 are provided on the upper and lower surfaces of the dielectric layer 11, respectively. However, the present disclosure is not limited to this. Alternatively, at least one of the first conductor layer 12 and the second conductor layer 13 may be provided on the inner surface of the dielectric layer 11. For example, providing the first conductor layer 12 on the inner surface of the dielectric layer 11 is equivalent to further stacking a dielectric layer on the first conductor layer 12.

[0172] In addition, the cylindrical wall waveguide can also be simply called a waveguide or a waveguide line. In addition, the cylindrical wall waveguide can also be called a stacked waveguide or a stacked waveguide line. Electromagnetic waves can be replaced by signals or transmission signals.

[0173] <Summary of Implementation Methods>

[0174] According to one embodiment of the present disclosure, a waveguide includes: a dielectric layer; a first conductor layer stacked in a stacking direction of the dielectric layer; a second conductor layer stacked at a position different from the first conductor layer in the stacking direction of the dielectric layer; a plurality of first conductor through-holes electrically connecting the first conductor layer and the second conductor layer; and a connecting portion electrically connecting two or more second conductor through-holes provided near a specific location, the specific location being a location present in a waveguide portion surrounded by the first conductor layer, the second conductor layer, and the plurality of first conductor through-holes, through which electromagnetic waves pass and where the electromagnetic waves are scattered.

[0175] In this waveguide, the specific portion is a portion where a scatterer that scatters the electromagnetic wave exists.

[0176] In the present waveguide, the scatterer is at least one of a conductor, a dielectric having a dielectric constant different from that of the dielectric layer, and a void.

[0177] In the present waveguide, the scatterer has a shape of a prism, a cylinder, a pyramid, a cone, a sphere, or a shape formed by combining these shapes.

[0178] In the present waveguide, at the specific location, the area of ​​the surface of the waveguide portion perpendicular to the direction of travel of the electromagnetic wave is at least twice the area of ​​the surface of the scatterer perpendicular to the direction of travel.

[0179] In the present waveguide, the specific portion is a portion of the waveguide portion where at least one of the size, shape, and center position of a surface perpendicular to the direction of travel of the electromagnetic wave changes in the direction of travel.

[0180] In this waveguide, the first conductor layer includes a third conductor layer and a fourth conductor layer stacked at different positions in the stacking direction of the dielectric layer, the specific location is a boundary where the first waveguide portion and the second waveguide portion are connected, the first waveguide portion is a waveguide portion surrounded by the third conductor layer, the second conductor layer, and the plurality of first conductor through-holes, and through which the electromagnetic wave passes, and the second waveguide portion is a waveguide portion surrounded by the fourth conductor layer, the second conductor layer, and the plurality of first conductor through-holes, and through which the electromagnetic wave passes.

[0181] In this waveguide, the first waveguide portion and the second waveguide portion share at least one dielectric layer.

[0182] In this waveguide, the first conductor layer includes a third conductor layer and a fourth conductor layer stacked on the dielectric layer, and the second conductor layer includes a fifth conductor layer and a sixth conductor layer stacked on the dielectric layer. The third conductor layer, the fourth conductor layer, the fifth conductor layer, and the sixth conductor layer are stacked at different positions in the stacking direction. The specific location is a boundary between the first waveguide portion and the second waveguide portion. The first waveguide portion is a waveguide portion surrounded by the third conductor layer, the fifth conductor layer, and the plurality of first conductor through-holes, and through which the electromagnetic wave passes. The second waveguide portion is a waveguide portion surrounded by the fourth conductor layer, the sixth conductor layer, and the plurality of first conductor through-holes, and through which the electromagnetic wave passes.

[0183] In this waveguide, the first waveguide portion and the second waveguide portion share at least one dielectric layer.

[0184] In the present waveguide, the connection portion is formed integrally with the two or more first conductor through-holes and is a conductor having a long side in a direction along a traveling direction of an electromagnetic wave passing through the waveguide portion.

[0185] While the embodiments have been described above with reference to the accompanying drawings, the present disclosure is not limited to these examples. Those skilled in the art will readily be able to devise various variations or modifications within the scope of the claims. It should be understood that these variations or modifications also fall within the technical scope of the present invention. Furthermore, the various components of the embodiments may be arbitrarily combined without departing from the spirit and scope of the present invention.

[0186] The disclosures of the specification, drawings, and abstract of Japanese patent application No. 2023-026210 filed on February 22, 2023 are incorporated herein by reference in their entirety.

[0187] Industrial Applicability

[0188] One embodiment of the present disclosure is useful for waveguides.

[0189] Description of Reference Numerals

[0190] 10, 20, 30, 40 cylindrical waveguides

[0191] 11 Dielectric layer

[0192] 12 First conductor layer

[0193] 13 Second conductor layer

[0194] 14, 23, 24, 33, 34, 41 conductor through-holes

[0195] 15 Conductors

[0196] 16, 26, 36 connecting conductors

[0197] 21 Third conductor layer

[0198] 22 Fourth conductor layer.

Claims

1. A waveguide comprising: dielectric layer; a first conductor layer stacked in a stacking direction of the dielectric layers; a second conductor layer stacked at a position different from that of the first conductor layer in the stacking direction of the dielectric layer; a plurality of first conductor through-holes electrically connecting the first conductor layer and the second conductor layer; as well as The connecting portion electrically connects two or more second conductor through-holes provided near a specific portion, wherein the specific portion is a portion in a waveguide portion surrounded by the first conductor layer, the second conductor layer, and the plurality of first conductor through-holes through which electromagnetic waves pass and where the electromagnetic waves are scattered.

2. The waveguide according to claim 1, wherein The specific portion is a portion where a scatterer that scatters the electromagnetic wave exists.

3. The waveguide according to claim 2, wherein The scatterer is at least one of a conductor, a dielectric having a different dielectric constant from that of the dielectric layer, and a void.

4. The waveguide according to claim 2, wherein The scatterer has a shape of a prism, a cylinder, a pyramid, a cone, a sphere, or a shape formed by combining these shapes.

5. The waveguide according to claim 2, wherein At the specific location, an area of ​​a surface of the waveguide portion perpendicular to the direction of travel of the electromagnetic wave is at least twice an area of ​​a surface of the scatterer perpendicular to the direction of travel.

6. The waveguide according to claim 1, wherein The specific portion is a portion of the waveguide portion where at least one of the size, shape, and center position of a surface perpendicular to the direction of travel of the electromagnetic wave changes in the direction of travel.

7. The waveguide according to claim 1, wherein The first conductor layer includes a third conductor layer and a fourth conductor layer stacked at different positions in a stacking direction of the dielectric layer. The specific portion is a boundary where a first waveguide portion and a second waveguide portion meet, the first waveguide portion being a waveguide portion surrounded by the third conductor layer, the second conductor layer, and the plurality of first conductor through-holes and through which the electromagnetic wave passes, and the second waveguide portion being a waveguide portion surrounded by the fourth conductor layer, the second conductor layer, and the plurality of first conductor through-holes and through which the electromagnetic wave passes.

8. The waveguide according to claim 7, wherein The first waveguide portion shares at least one dielectric layer with the second waveguide portion.

9. The waveguide according to claim 1, wherein The first conductor layer has a third conductor layer and a fourth conductor layer stacked on the dielectric layer. The second conductor layer includes a fifth conductor layer and a sixth conductor layer stacked on the dielectric layer. The third conductor layer, the fourth conductor layer, the fifth conductor layer, and the sixth conductor layer are stacked at different positions from each other in a stacking direction. The specific portion is a boundary where a first waveguide portion and a second waveguide portion are connected. The first waveguide portion is a waveguide portion surrounded by the third conductor layer, the fifth conductor layer, and the plurality of first conductor through-holes, through which the electromagnetic wave passes. The second waveguide portion is a waveguide portion surrounded by the fourth conductor layer, the sixth conductor layer, and the plurality of first conductor through-holes, through which the electromagnetic wave passes.

10. The waveguide according to claim 9, wherein The first waveguide portion shares at least one dielectric layer with the second waveguide portion.

11. The waveguide according to claim 1, wherein The connecting portion is formed integrally with the two or more first conductor through-holes and is a conductor having a long side in a direction along a traveling direction of electromagnetic waves passing through the waveguide portion.

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