JP2016178571A - Waveguide/transmission line converter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To satisfy low reflection characteristics and high permeation characteristics with good reproducibility, even in an actual case where the arrangement accuracy of the pattern of a dielectric substrate and the location accuracy between the pattern of a dielectric substrate and a waveguide are assumed low, in a waveguide/transmission line converter using a high frequency band of milli-wave zone, or the like.SOLUTION: In a patch antenna, broadband is applied by disposing a parasitic element in the vicinity of a patch element. More specifically, in a waveguide/transmission line converter 2, broadband is attained by disposing a passive element 29 on a layer in the vicinity of a matching element 28 and different therefrom in the waveguide direction, and low reflection characteristics and high permeation characteristics can be satisfied with good reproducibility, even in an actual case where the arrangement accuracy of the pattern of first and second dielectric substrates 23, 24 and the location accuracy between the pattern of the first and second dielectric substrates 23, 24 and a waveguide 21 are assumed low.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a waveguide / transmission line converter that mutually converts power transmitted by a waveguide and power transmitted by a transmission line.

  The waveguide / transmission line converter is applied to power supply to an antenna device and is disclosed in Patent Documents 1 and 2 and the like. First, in Patent Document 1, a transmission line is inserted at a position where the electric field strength is high in the waveguide. However, in Patent Document 1, a waveguide short-circuit surface is required at a position that is separated from the transmission line along the waveguide by a distance equal to approximately ¼ of the wavelength of the electromagnetic wave in the waveguide. Therefore, in Patent Document 1, the waveguide / transmission line converter cannot be reduced in size, and the structure that forms the short-circuited surface exists in front of the surface that forms the antenna device. Cause deterioration of sex.

JP 2004-320460 A JP 2000-244212 A

  Next, in Patent Document 2, a technique of coupling a transmission line to a matching element and propagating radio waves from the transmission line to a waveguide is used. As will be apparent from the following description, in Patent Document 2, the waveguide / transmission line converter can be reduced in size compared to Patent Document 1, and the short-circuit surface that causes the directivity of the antenna device to deteriorate. The structure which forms can be eliminated.

  The configuration of a prior art waveguide / transmission line converter is shown in FIG. The uppermost stage shows a side sectional view of the waveguide / transmission line converter 1. The second stage shows an AA plane cross-sectional view of the waveguide / transmission line converter 1. The third stage shows a cross-sectional view taken along the line B-B of the waveguide / transmission line converter 1. The bottom row shows the electric field distribution in the direction of the resonance length of the matching element 17 described later.

  The waveguide / transmission line converter 1 includes a dielectric substrate 13, a short-circuit metal layer 14, a metal member 15, a ground metal layer 16, and a matching element 17.

  The dielectric substrate 13 is disposed so as to close the opening of the waveguide 11. The surface of the dielectric substrate 13 is a surface perpendicular to the waveguide direction of the waveguide 11. In the second and third stages of FIG. 1, the portion of the dielectric substrate 13 where the pattern is arranged is shown in white, and the portion of the dielectric substrate 13 where the pattern is not arranged is shown in diagonal lines.

  The short-circuit metal layer 14 is disposed on the surface of the dielectric substrate 13 and outside the waveguide 11, and is disposed on the surface of the metal member 15 penetrating the dielectric substrate 13 and the surface of the dielectric substrate 13 and on the outer frame of the waveguide 11. The ground metal layer 16 is held at the same potential as the waveguide 11.

The matching element 17 is disposed on the surface of the dielectric substrate 13 and inside the waveguide 11, is electromagnetically coupled to the transmission line 12 via the dielectric substrate 13, and has an effective wavelength in the environment around the dielectric substrate 13. A resonance length (approximately λ _g / 2) for raising an electromagnetic wave of λ _g as a standing wave is provided in the electric field direction in the waveguide 11 and the feeding direction of the transmission line 12.

  The characteristics of a prior art waveguide / transmission line converter are shown in FIG. As described above, the reflection characteristic shown in FIG. 2 becomes low in a narrow band around the center frequency of the waveguide / transmission line converter 1, and the transmission characteristic shown in FIG. High in a narrow band around the center frequency of the device 1. Here, the low reflection characteristic and the high transmission characteristic shown in FIG. 2 are ideal for assuming that the arrangement accuracy of the pattern of the dielectric substrate 13 and the positional accuracy between the pattern of the dielectric substrate 13 and the waveguide 11 are high. It is a simulation result in the case of.

  Therefore, in the actual case where the arrangement accuracy of the pattern of the dielectric substrate 13 and the positional accuracy between the pattern of the dielectric substrate 13 and the waveguide 11 are assumed to be low, the low reflection characteristics and the high transmission shown in FIG. The characteristics are likely not to be satisfied with good reproducibility. This is particularly noticeable in the waveguide / transmission line converter 1 using a high frequency band such as the millimeter wave band.

  Therefore, in order to solve the above-described problems, the present invention provides a waveguide / transmission line converter that uses a high frequency band such as a millimeter wave band. The object is to satisfy the low reflection characteristic and the high transmission characteristic with good reproducibility even in the actual case where the position accuracy between the wave tubes is assumed to be low.

  As a first means for achieving the above object, in the patch antenna, it is applied to increase the bandwidth by arranging a parasitic element in the vicinity of the patch element. In other words, in the waveguide / transmission line converter, by providing parasitic elements in different layers in the vicinity of the matching element and in the waveguide direction, the bandwidth can be increased. Even in an actual case where it is assumed that the positioning accuracy between the dielectric substrate pattern and the position accuracy between the pattern of the dielectric substrate and the waveguide is low, low reflection characteristics and high transmission characteristics can be satisfied with good reproducibility.

  Specifically, the present invention is a waveguide / transmission line converter that mutually converts power transmitted by a waveguide and power transmitted by a transmission line, A first dielectric substrate disposed so as to close the opening; a second dielectric substrate disposed on the surface of the first dielectric substrate and outside the waveguide; and the first and first dielectric substrates Between the two dielectric substrates, coupled to the transmission line, and having a resonance length for raising an electromagnetic wave having an effective wavelength as a standing wave in an environment around the first and second dielectric substrates. A matching element having an electric field direction in the wave tube and a feeding direction of the transmission line; a surface of the first dielectric substrate and inside the waveguide; and electromagnetically coupled to the matching element; A parasitic element having a resonance length different from the resonance length of the element. A waveguide / transmission line converter according to claim.

  According to this configuration, in addition to the above-described effects, (1) since two dielectric substrates are used, the thickness of the dielectric substrate is increased to increase the strength of the dielectric substrate. (2) Since the matching element and the parasitic element are arranged in different layers, the electromagnetic wave between the matching element and the parasitic element can be adjusted by adjusting the thickness of the first dielectric substrate. (3) The size of the pattern of the dielectric substrate including the matching element disposed between the two dielectric substrates can be reduced.

  As a second means for achieving the above object, in the patch antenna, the application of widening the band by arranging a parasitic element in the vicinity of the patch element is applied. That is, in the waveguide / transmission line converter, by providing a parasitic element in the same layer in the vicinity of the matching element and in the waveguide direction as the matching element, the bandwidth can be increased. Even in the actual case where the pattern placement accuracy and the positional accuracy between the pattern of the dielectric substrate and the waveguide are assumed to be low, low reflection characteristics and high transmission characteristics can be satisfied with good reproducibility.

  Specifically, the present invention is a waveguide / transmission line converter that mutually converts power transmitted by a waveguide and power transmitted by a transmission line, A dielectric substrate disposed so as to close the opening, and disposed on a surface of the dielectric substrate and inside the waveguide, coupled to the transmission line, and having an effective wavelength in an environment around the dielectric substrate; A matching element having a resonance length for raising an electromagnetic wave as a standing wave in an electric field direction in the waveguide and a feeding direction of the transmission line, and disposed on the surface of the dielectric substrate and in the waveguide, A waveguide / transmission line converter comprising: a parasitic element that is electromagnetically coupled to a matching element and has a resonance length different from that of the matching element.

  According to this configuration, since only one dielectric substrate is used in addition to the above-described effects, the manufacture of the waveguide / transmission line converter can be facilitated.

  As described above, according to the present invention, in the waveguide / transmission line converter using a high frequency band such as the millimeter wave band, the placement accuracy of the pattern of the dielectric substrate and the position between the pattern of the dielectric substrate and the waveguide Even in an actual case where accuracy is assumed to be low, low reflection characteristics and high transmission characteristics can be satisfied with good reproducibility.

It is a figure which shows the structure of the waveguide / transmission line converter of a prior art. It is a figure which shows the characteristic of the waveguide / transmission line converter of a prior art. It is a figure which shows the structure of the 1st waveguide / transmission line converter of 1st Embodiment. It is a figure which shows the structure of the 2nd waveguide / transmission line converter of 1st Embodiment. It is a figure which shows the characteristic of the waveguide / transmission line converter of 1st Embodiment. It is a figure which shows the structure of the waveguide / transmission line converter of 2nd Embodiment.

  Embodiments of the present invention will be described with reference to the accompanying drawings. The embodiments described below are examples of the present invention, and the present invention is not limited to the following embodiments.

(First embodiment)
FIG. 3 shows the configuration of the first waveguide / transmission line converter according to the first embodiment. In the waveguide / transmission line converter 2, the matching element 28 and the parasitic element 29 are arranged in different layers in the waveguide direction, and the first dielectric substrate 23 is arranged outside the waveguide 21. When the waveguide / transmission line converter 2 is applied to a planar array antenna, a plurality of waveguide / transmission line converter 2 patterns are formed on the first and second dielectric substrates 23 and 24. Good.

  The first column in the left column shows a side sectional view of the waveguide / transmission line converter 2. The second column in the left column shows a cross-sectional plan view taken along the line CC of the waveguide / transmission line converter 2. The uppermost column in the right column shows a cross-sectional view taken along the line DD of the waveguide / transmission line converter 2. The second column on the right column shows an EE plane cross-sectional view of the waveguide / transmission line converter 2 as viewed in the direction of the arrows. The third column on the right column shows the electric field distribution in the direction of the resonance length of the matching element 28. The lowermost column in the right column shows the electric field distribution in the direction of the resonance length of the parasitic element 29.

  The configuration of the second waveguide / transmission line converter of the first embodiment is shown in FIG. In the waveguide / transmission line converter 3, the matching element 38 and the parasitic element 39 are arranged in different layers in the waveguide direction, and the first dielectric substrate 33 is arranged inside the waveguide 31. When the waveguide / transmission line converter 3 is applied to a planar array antenna, a plurality of waveguide / transmission line converter 3 patterns may be formed on the second dielectric substrate 34.

  The first column in the left column shows a side sectional view of the waveguide / transmission line converter 3. The second column in the left column shows an FF plane cross-sectional view of the waveguide / transmission line converter 3 as viewed in the direction of arrows. The uppermost column in the right column shows an GG plane cross-sectional view of the waveguide / transmission line converter 3 as viewed in the direction of the arrows. The second column in the right column shows an HH plane cross-sectional view of the waveguide / transmission line converter 3 as viewed in the direction of the arrows. The third column on the right column shows the electric field distribution in the direction of the resonance length of the matching element 38. The lowermost column in the right column shows the electric field distribution in the direction of the resonance length of the parasitic element 39.

  The waveguide / transmission line converter 2 includes a first dielectric substrate 23, a second dielectric substrate 24, a short metal layer 25, a metal member 26, a ground metal layer 27, a matching element 28, and a parasitic element 29. Prepare. The waveguide / transmission line converter 3 includes a first dielectric substrate 33, a second dielectric substrate 34, a short-circuit metal layer 35, a metal member 36, a ground metal layer 37, a matching element 38, and a parasitic element 39. Prepare.

  The first dielectric substrates 23 and 33 are disposed so as to close the openings of the waveguides 21 and 31, respectively. The first dielectric substrate 23 is disposed outside the waveguide 21 and is formed with a pattern of a plurality of waveguide / transmission line converters 2 in the planar array antenna. The first dielectric substrate 33 is disposed inside the waveguide 31 and is formed with a single waveguide / transmission line converter 3 pattern in the planar array antenna. The surfaces of the first dielectric substrates 23 and 33 are surfaces perpendicular to the waveguide direction of the waveguides 21 and 31, respectively. 3 and 4, the portion where the pattern is arranged in the first dielectric substrate 23, 33 is shown in white, and the pattern is arranged in the first dielectric substrate 23, 33. Portions that are not displayed are indicated by diagonal lines.

  The second dielectric substrates 24 and 34 are disposed on the surfaces of the first dielectric substrates 23 and 33 and outside the waveguides 21 and 31, respectively. The second dielectric substrates 24 and 34 are each formed with a pattern of a plurality of waveguide / transmission line converters 2 and 3 in a planar array antenna. The surfaces of the second dielectric substrates 24 and 34 are surfaces perpendicular to the waveguide direction of the waveguides 21 and 31, respectively. 3 and 4, in the second column on the left column and the uppermost column on the right column, portions of the second dielectric substrates 24 and 34 where the patterns are arranged are shown in white, and the second dielectric substrates 24 and 34 are shown in white. A portion where no pattern is arranged is indicated by hatching.

  The short-circuit metal layer 25 is disposed on the surface of the second dielectric substrate 24 on the side where the waveguide 21 does not extend, and the metal member 26 and the first metal member 26 penetrating the first and second dielectric substrates 23 and 24. The same potential as that of the waveguide 21 is maintained by the ground metal layer 27 disposed on the surface of the dielectric substrate 23 and on the outer frame of the waveguide 21. The short-circuit metal layer 35 is disposed on the surface of the second dielectric substrate 34 on the side where the waveguide 31 does not extend, and the metal member 36 that penetrates the second dielectric substrate 34 and the second dielectric substrate 34. Is held at the same potential as the waveguide 31 by the ground metal layer 37 disposed on the surface of the waveguide 31 and on the outer frame of the waveguide 31. In the waveguide / transmission line converters 2 and 3, there is a difference in the method of laminating the dielectric substrates. Therefore, which of the dielectric substrates the metal members 26 and 36 penetrate, and which of the ground metal layers 27 and 37 is It is arranged on the surface of the dielectric substrate or different.

The matching elements 28 and 38 are disposed between the first and second dielectric substrates (23, 24) and (33, 34), respectively, and the transmission line 22 is interposed via the second dielectric substrates 24 and 34. , 32 and a resonance length for standing as an electromagnetic wave having an effective wavelength λ _g in an environment around the first and second dielectric substrates (23, 24), (33, 34). (Approximately λ _g / 2) in the electric field direction in the waveguides 21 and 31 and the feeding direction of the transmission lines 22 and 32.

The parasitic elements 29 and 39 are disposed on the surfaces of the first dielectric substrates 23 and 33 and inside the waveguides 21 and 31, respectively, and are electromagnetically coupled to the matching elements 28 and 38. 38 has a resonance length (approximately λ _{g '} / 2) that is different from the resonance length (approximately λ _g / 2) of 38.

  Here, the matching elements 28 and 38 and the transmission lines 22 and 32 exist in different layers. And the front-end | tip shape of the transmission lines 22 and 32 is a stub or slot with a notch. Therefore, the matching elements 28 and 38 and the transmission lines 22 and 32 can realize electromagnetic coupling.

  3 and 4, the metal member 26 penetrates the first and second dielectric substrates 23 and 24 along the cross sections of the two wide wall surfaces and the two narrow wall surfaces of the waveguide 21. The metal member 36 is a “through hole” that penetrates the second dielectric substrate 34 along the cross sections of the two wide wall surfaces and the two narrow wall surfaces of the waveguide 31. Is formed. As a modification, the metal member 26 is a “conductor wall” that penetrates the first and second dielectric substrates 23 and 24 along the cross sections of the two wide wall surfaces and the two narrow wall surfaces of the waveguide 21. The metal member 36 may be a “conductor wall” that penetrates the second dielectric substrate 34 along the cross sections of the two wide wall surfaces and the two narrow wall surfaces of the waveguide 31. Good.

  The characteristics of the waveguide / transmission line converter of the first embodiment are shown in FIG. As described above, the reflection characteristic shown in FIG. 5 becomes low in a wide band around the center frequency of the waveguide / transmission line converters 2 and 3, and the transmission characteristic shown in FIG. It becomes high in a wide band around the center frequency of the converters 2 and 3. Here, the low reflection characteristic and the high transmission characteristic shown in FIG. 5 are the pattern placement accuracy of the first and second dielectric substrates (23, 24) and (33, 34) and the first and second dielectrics. It is a simulation result in the ideal case where the positional accuracy between the pattern of the body substrates (23, 24), (33, 34) and the waveguides 21, 31 is assumed to be high.

  Therefore, the pattern placement accuracy of the first and second dielectric substrates (23, 24), (33, 34) and the pattern of the first and second dielectric substrates (23, 24), (33, 34). In the actual case where the positional accuracy between the waveguides 21 and 31 is assumed to be low, the low reflection characteristics and high transmission characteristics shown in FIG. 5 are likely to be satisfied with good reproducibility. This is particularly noticeable in the waveguide / transmission line converters 2 and 3 using a high frequency band such as a millimeter wave band.

  In the first embodiment, unlike the second embodiment, two dielectric substrates (23, 24), (33, 34) are used, so the thickness is increased and the dielectric substrates (23, 24) are used. ), (33, 34), the positional accuracy between the pattern and the waveguides 21, 31 can be increased.

  Furthermore, in the first embodiment, unlike the second embodiment, since the matching elements 28 and 38 and the parasitic elements 29 and 39 are arranged in different layers, the thickness of the first dielectric substrate (23, 33). By adjusting the electromagnetic field, the electromagnetic coupling between the matching elements 28, 38 and the parasitic elements 29, 39 can be strengthened, and the two dielectric substrates (23, 24), (33, 34) The pattern size of the dielectric substrates (23, 24), (33, 34) including the matching elements 28, 38 disposed therebetween can be reduced.

(Second Embodiment)
The configuration of the waveguide / transmission line converter of the second embodiment is shown in FIG. In the waveguide / transmission line converter 4, the matching element 47 and the parasitic element 48 are arranged in the same layer in the waveguide direction, and a plurality of patterns are formed on the dielectric substrate 43 to feed the array antenna. It is applicable to.

  The top row shows a side sectional view of the waveguide / transmission line converter 4. The second stage shows an I-I plane cross-sectional view of the waveguide / transmission line converter 4. The third stage shows a cross-sectional view taken along the line JJ of the waveguide / transmission line converter 4. The fourth stage shows the electric field distribution in the direction of the resonance length of the matching element 47. The bottom row shows the electric field distribution in the direction of the resonance length of the parasitic element 48.

  The waveguide / transmission line converter 4 includes a dielectric substrate 43, a short-circuit metal layer 44, a metal member 45, a ground metal layer 46, a matching element 47 and a parasitic element 48.

  The dielectric substrate 43 is disposed so as to close the opening of the waveguide 41. The dielectric substrate 43 is disposed outside the waveguide 41, and a plurality of patterns are formed. The surface of the dielectric substrate 43 is a surface perpendicular to the waveguide direction of the waveguide 41. In the second and third stages of FIG. 6, the portion of the dielectric substrate 43 where the pattern is arranged is indicated by a white background, and the portion of the dielectric substrate 43 where the pattern is not arranged is indicated by oblique lines.

  The short-circuit metal layer 44 is disposed on the surface of the dielectric substrate 43 and outside the waveguide 41, and is disposed on the metal member 45 penetrating the dielectric substrate 43 and the surface of the dielectric substrate 43 and on the outer frame of the waveguide 41. The ground metal layer 46 is held at the same potential as the waveguide 41.

The matching element 47 is disposed on the surface of the dielectric substrate 43 and inside the waveguide 41, is electromagnetically coupled to the transmission line 42 via the dielectric substrate 43, and has an effective wavelength in the environment around the dielectric substrate 43. A resonance length (approximately λ _g / 2) for raising an electromagnetic wave of λ _g as a standing wave is provided in the electric field direction in the waveguide 41 and the feeding direction of the transmission line 42.

The parasitic element 48 is disposed on the surface of the dielectric substrate 43 and inside the waveguide 41, is electromagnetically coupled to the matching element 47, and has a resonance length different from the resonance length (approximately λ _g / 2) of the matching element 47. Has a length (approximately λ _g '/ 2). One parasitic element 48 is arranged at a position opposite to the matching element 47 along the direction of the cross section of the wide wall surface of the waveguide 41.

  Here, the matching element 47 and the transmission line 42 are in different layers. And the front-end | tip shape of the transmission line 42 is a stub or slot with a notch. Therefore, the matching element 47 and the transmission line 42 can realize electromagnetic coupling.

  In the description of FIG. 6, the metal member 45 is formed as a “through hole” that penetrates the dielectric substrate 43 along the cross sections of the two wide wall surfaces and the two narrow wall surfaces of the waveguide 41. As a modification, the metal member 45 may be a “conductor wall” that penetrates the dielectric substrate 43 along the cross sections of the two wide wall surfaces and the two narrow wall surfaces of the waveguide 41.

  In the second embodiment, similar to the first embodiment, the reflection characteristic is low in a wide band around the center frequency of the waveguide / transmission line converter 4, and the transmission characteristic is the waveguide / transmission line. It becomes high in a wide band around the center frequency of the transducer 4.

  Therefore, in the second embodiment, as in the first embodiment, it is assumed that the arrangement accuracy of the pattern of the dielectric substrate 43 and the positional accuracy between the pattern of the dielectric substrate 43 and the waveguide 41 are high. Compared to the ideal case, in the actual case where the arrangement accuracy of the pattern of the dielectric substrate 43 and the positional accuracy between the pattern of the dielectric substrate 43 and the waveguide 41 are assumed to be low, low reflection characteristics and high transmission The characteristics are likely to be satisfied with good reproducibility. This is particularly noticeable in the waveguide / transmission line converter 4 using a high frequency band such as a millimeter wave band.

  In the second embodiment, unlike the first embodiment, since only one dielectric substrate 43 is used, the manufacture of the waveguide / transmission line converter 4 can be facilitated.

  The waveguide / transmission line converter according to the present invention provides a dielectric substrate pattern placement accuracy and a gap between the dielectric substrate pattern and the waveguide in feeding an array antenna using a high frequency band such as a millimeter wave band. Even in an actual case where the positional accuracy of the sensor is assumed to be low, it can be applied for the purpose of satisfying low reflection characteristics and high transmission characteristics with good reproducibility.

1, 2, 3, 4: Waveguide / transmission line converters 11, 21, 31, 41: Waveguides 12, 22, 32, 42: Transmission lines 13, 43: Dielectric substrates 23, 33: First Dielectric substrates 24, 34: second dielectric substrates 14, 25, 35, 44: short-circuit metal layers 15, 26, 36, 45: metal members 16, 27, 37, 46: ground metal layers 17, 28, 38, 47: matching elements 29, 39, 48: parasitic elements

Claims (2)

Power transmitted by the waveguide;
Power transmitted by the transmission line;
A waveguide / transmission line converter for converting between
A first dielectric substrate disposed so as to close the opening of the waveguide;
A second dielectric substrate disposed on the surface of the first dielectric substrate and outside the waveguide;
An electromagnetic wave disposed between the first and second dielectric substrates, coupled to the transmission line, and having an effective wavelength electromagnetic wave in a surrounding environment of the first and second dielectric substrates as a standing wave A matching element having a resonance length in the direction of the electric field in the waveguide and in the feeding direction of the transmission line;
A parasitic element disposed on the surface of the first dielectric substrate and inside the waveguide, electromagnetically coupled to the matching element, and having a resonance length different from that of the matching element;
A waveguide / transmission line converter comprising: Power transmitted by the waveguide;
Power transmitted by the transmission line;
A waveguide / transmission line converter for converting between
A dielectric substrate disposed to close the opening of the waveguide;
A resonance length is disposed on the surface of the dielectric substrate and inside the waveguide, coupled to the transmission line, and configured to generate an electromagnetic wave having an effective wavelength as a standing wave in an environment around the dielectric substrate. A matching element having an electric field direction in the wave tube and a feeding direction of the transmission line;
A parasitic element disposed on the surface of the dielectric substrate and inside the waveguide, electromagnetically coupled to the matching element, and having a resonance length different from that of the matching element;
A waveguide / transmission line converter comprising:

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