US3462713A - Waveguide-stripline transducer - Google Patents

Waveguide-stripline transducer Download PDF

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Publication number
US3462713A
US3462713A US654480A US3462713DA US3462713A US 3462713 A US3462713 A US 3462713A US 654480 A US654480 A US 654480A US 3462713D A US3462713D A US 3462713DA US 3462713 A US3462713 A US 3462713A
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Prior art keywords
guide
waveguide
stripline
strip
probe
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Expired - Lifetime
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US654480A
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English (en)
Inventor
Reinhard H Knerr
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AT&T Corp
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Bell Telephone Laboratories Inc
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P5/00—Coupling devices of the waveguide type
    • H01P5/08—Coupling devices of the waveguide type for linking dissimilar lines or devices
    • H01P5/10—Coupling devices of the waveguide type for linking dissimilar lines or devices for coupling balanced lines or devices with unbalanced lines or devices
    • H01P5/107—Hollow-waveguide/strip-line transitions

Definitions

  • This invention relates to radio frequency transducers and more particularly to a transducer for coupling together a radio frequency waveguide of the hollow conductor type and one of the parallel strip, multiple conductor type, such as the stripline or Microstrip.
  • the portion of the center conductor directly inserted into the waveguide is provided with a pattern of substantially lumped reactive elements, at least one of which is within the guide, the others, if any, being close to the guide.
  • these reactive elements are tuned with the distributed reactance of the stripline center conductor to a plurality of spaced individual frequencies within the band, the resulting series of stagger tuned circuits produces a broadband match.
  • Each reactive element may be either in the form of a capacitive crosspiece or stub with respect to the center conductor, or altematvely, an inductive notch in the 3,462,713 Patented Aug. 19, 1969 center conductor.
  • Both stubs and notches have been used in the art as reactances to modify the characteristic impedance of the strip for impedance matching purposes and it is known that they can be substituted one for the other if accompanied by physical relocation of one-quarter wavelength along the length of a stripline.
  • FIG. l is a cutaway perspective view of a waveguidestripline transducer in accordance with the invention.
  • FIG. 2a is a cross sectional view taken through FIG. 1 as indicated to show the stripline pattern in accordance with the invention
  • FIG. 2b is the approximate equivalent circuit of the pattern of FIG. 2a;
  • FIG. 3 is a typical coupling versus frequency characteristic for the embodiment of FIGS. l and 2a.
  • FIGS. 4a through 6a are alternative stripline patterns together with their approximate equivalent circuits in FIGS. 4b through 6b respectively.
  • FIG. 1 an illustrative embodiment of a transducer is shown which provides coupling between a rectangular conductively bounded waveguide 10 and a parallel conductor stripline 11.
  • line 11 is specifically shown as the symmetrical type having a thin center conductor or strip 12 interposed between a pair of ground planes which are formed in the particular embodiment illustrated by the wider inside surfaces of a channel cut in body 13.
  • Strip conductor 12 is typically supported in this channel by being formed of conductive material plated or printed upon a supporting substrate 14 of high dielectric material.
  • the invention may be applied to lines of self-supporting center conductor or to the unsymmetrical type of line, sometimes referred to as the Microstrip, in which a first thin conductor is related to only one ground plane.
  • the ground planes may be printed or plated surfaces in the familiar sandwich construction.
  • the coupling between guide 10 and stripline 11 is formed by extending center conductor 12 through an elongated aperture 15 in the wide wall of guide 10 ⁇ which aperture preferably has the same cross sectional dimensions as and is aligned with the channel in body 13.
  • the extended center conductor forms a strip shaped probe 16 within the guide parallel to the undisturbed electric field polarization in guide 10.
  • the position of aperture 15 is displaced away form the longitudinal center line of guide 10 in accordance with known impedance matching considerations and the end of guide 10 is closed by a short circuit, piston or conductive transverse wall 19 spaced from the position of the probe 16.
  • stripline ground planes which as to the upper portion of strip 12 comprised the surfaces of the channel in body 13, are now effectively replaced as to probe portion 16 by the walls of guide 10.
  • stripline stubs extending on one or both sides of the center conductor constitute capacitive reactances, as Shown for example, in the above-mentioned Arditi patent.
  • the coupled bandwidth is broadened by stubs 17 and 18 of this type placed, however, upon the probe 16 portion of conductor 12 within guide 10.
  • stubs 17 and 18 have such dimensions and locations on probe 16 that they form with the distributed reactances of probe 16 within the guide, a second resonance at a frequency within the band of interest but adjacent to and different from the resonant frequency produced as a result of the distributed reactances of probe 16.
  • the interaction of these two resonant circuits has the same effect as stagger tuned circuits used in filters or equalizers, for example, and broadens the coupled bandwidth as will be shown in connection with FIG. 3.
  • FIG. 2a is -a cross sectional view taken through guide in front of dielectric support 14 and shows the stripline center conductor 12 forming probe 16 as it extends within guide 10.
  • An equivalent circuit is shown in FIG. 2b having inductances L and certain capacitances C and Ca representing the distributed reactances of that portion of strip 12 within guide 10. Outside of guide 10 reactances corresponding only to L and C are present, and customary design usually results in a net inductive reactance and nonresonant condition at the frequency of interest.
  • capacitance Ca represents that portion of the total distribtued capacity that is in series with the center conductor due to the electric field component in guide 10 parallel to probe 16 of strip 12 which depends in turn upon the distance a of FIG. 2a.
  • the capacity C represents the remaining small distributed capacity due to the electric eld perpendicular to the strip.
  • Stubs 17 and 18 produce a substantially lumped capacity represented on the equivalent circuit of FIG. 2b by Cb, large compared to C, and dependent upon the dimension b of FIG. 2a as well as upon the width of stubs 17 and 18.
  • the spacing Af between the respective hump center freqeuncies f1 and f2 is readily adjusted by control of the spacing of stubs 17 and 18 from the end of probe 16. This spacing determines the amount of distributed inductance L along with a smaller amount of distributed capacitance C included within each circuit loop. Obviously, in a practical embodiment the parameters are not as discrete as the equivalent circuit seems to indicate. Furthermore, since other variables include 'the position of the short, the length of the probe and its position, proper proportions of the center conductor pattern are best determined on an empirical basis after an approximate choice of the other parameters on the basis of known coaxial probe relationships.
  • One or more additional capacitive reactances, further producing one or more separate resonant circuits, may be added to further increase the bandwidth.
  • stubs 21 and 22 are added which have dimensions different from those of stubs 17 and 18 and are spaced therefrom along center conductor strip 12.
  • the dimension c of stubs 21 and 22 determines a capacity Cc as shown on FIG. 4b and the spacing of stubs 21 and 22 from stubs 4 17 and 18 determines the value of L and C as required to produce resonance at a new frequency f3.
  • Notches such as 23 and 24 of FIG. 5a reduce the width of center conductor 12 and introduce an inductance in series with the line as indicated by inductance Ld of FIG. 5b.
  • a notch is equivalent to a stub located one-quarter Wavelength further along the line from the position of the stub which is replaces.
  • a plurality of notches 25 as shown in FIG. 6a and having the equivalent circuit of FIG. 6b can similarly be employed.
  • the added reactances can only produce the improvement in accordance with the invention if they tune with the distributed reactance of probe 16 within the guide. Otherwise added reactance only serves to modify the characteristic impedance of the line in accordance with prior art teachings, and only incidentally, if at all, to effect bandwidth of any coupling means at the end of the strip. It has been found, however, that if at least one of the added reactances is within the guide, additional improvement may be obtained from others not physically within the guide but which are relatively close thereto. It is believed that improvement in accordance with the invention can be obtained so long as the added reactance is in the transition region where field patterns are changing from those of the waveguide mode to those of the stripline mode. It is further believed that a reactance more than one-quarter wavelength away from the guide can have little direct effect upon the coupled bandwidth.
  • any given pattern may be turned ninety degrees in the guide so that its plane is perpendicular to the narrow side without effecting the coupled bandwidth.
  • This versatility is one of the primary advantages of the coupling in accordance with the invention. In certain experimental models it was, however, found necessary to make slight readjustment of the shorting piston position when the pattern is rotated.
  • one of said lumped reactances comprises a conductive crosspiece upon said strip within said hollow guide and the other comprises a notch in said strip.
  • one of said lumped reactances comprises at least one conductive stub upon said strip within said guide.
  • one OTHER REFERENCES of said lumped reactances comprises at least one notch Parallel-Plate Transmission Systems for Mirowave Frequencies-A. F. Harvey--The Proceedings of the Institution of Electrical Engineers, London (Part B No.
  • said lumped reactances comprises conductive crosspieces of diierent size pon said strip within said guide.

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US654480A 1967-07-19 1967-07-19 Waveguide-stripline transducer Expired - Lifetime US3462713A (en)

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US65448067A 1967-07-19 1967-07-19

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US (1) US3462713A (de)
BE (1) BE718075A (de)
DE (1) DE1766787B1 (de)
FR (1) FR1572049A (de)
GB (1) GB1227559A (de)
NL (1) NL6810091A (de)

Cited By (31)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3579149A (en) * 1969-12-08 1971-05-18 Westinghouse Electric Corp Waveguide to stripline transition means
US3654572A (en) * 1970-11-05 1972-04-04 Rca Corp Waveguide structure
US3732508A (en) * 1970-12-23 1973-05-08 Fujitsu Ltd Strip line to waveguide transition
US3924204A (en) * 1973-05-07 1975-12-02 Lignes Telegraph Telephon Waveguide to microstrip coupler
US3969691A (en) * 1975-06-11 1976-07-13 The United States Of America As Represented By The Secretary Of The Navy Millimeter waveguide to microstrip transition
US4052683A (en) * 1974-02-28 1977-10-04 U.S. Philips Corporation Microwave device
US4550296A (en) * 1982-05-13 1985-10-29 Ant Nachrichtentechnik Gmbh Waveguide-microstrip transition arrangement
JPH0234002A (ja) * 1988-07-23 1990-02-05 Nec Corp 同軸導波管変換器
US4901040A (en) * 1989-04-03 1990-02-13 American Telephone And Telegraph Company Reduced-height waveguide-to-microstrip transition
EP0458226A2 (de) * 1990-05-22 1991-11-27 CSELT Centro Studi e Laboratori Telecomunicazioni S.p.A. Polarisationsweiche zwischen einem zirkularen Wellenleiter und einem Koaxialkabel
US5093640A (en) * 1989-09-29 1992-03-03 Hewlett-Packard Company Microstrip structure having contact pad compensation
US20150077198A1 (en) * 2013-09-13 2015-03-19 Toko, Inc. Dielectric Waveguide Resonator and Dielectric Waveguide Filter Using the Same
US20190063983A1 (en) * 2017-08-28 2019-02-28 Vega Grieshaber Kg Waveguide coupling for a fill level radar
US10468736B2 (en) * 2017-02-08 2019-11-05 Aptiv Technologies Limited Radar assembly with ultra wide band waveguide to substrate integrated waveguide transition
RU2735366C1 (ru) * 2020-02-05 2020-10-30 Акционерное общество "Научно-производственное предприятие "Пульсар" Соосный переход с симметричного полоска на волновод прямоугольного сечения
US10992018B2 (en) 2016-07-22 2021-04-27 Mitsubishi Electric Corporation Coaxial-waveguide-to-hollow- waveguide transition circuit
US11362436B2 (en) 2020-10-02 2022-06-14 Aptiv Technologies Limited Plastic air-waveguide antenna with conductive particles
US11444364B2 (en) 2020-12-22 2022-09-13 Aptiv Technologies Limited Folded waveguide for antenna
US11502420B2 (en) 2020-12-18 2022-11-15 Aptiv Technologies Limited Twin line fed dipole array antenna
US11527808B2 (en) 2019-04-29 2022-12-13 Aptiv Technologies Limited Waveguide launcher
US11616306B2 (en) 2021-03-22 2023-03-28 Aptiv Technologies Limited Apparatus, method and system comprising an air waveguide antenna having a single layer material with air channels therein which is interfaced with a circuit board
US11626668B2 (en) 2020-12-18 2023-04-11 Aptiv Technologies Limited Waveguide end array antenna to reduce grating lobes and cross-polarization
US11668787B2 (en) 2021-01-29 2023-06-06 Aptiv Technologies Limited Waveguide with lobe suppression
US11681015B2 (en) 2020-12-18 2023-06-20 Aptiv Technologies Limited Waveguide with squint alteration
US11721905B2 (en) 2021-03-16 2023-08-08 Aptiv Technologies Limited Waveguide with a beam-forming feature with radiation slots
US11749883B2 (en) 2020-12-18 2023-09-05 Aptiv Technologies Limited Waveguide with radiation slots and parasitic elements for asymmetrical coverage
US11757166B2 (en) 2020-11-10 2023-09-12 Aptiv Technologies Limited Surface-mount waveguide for vertical transitions of a printed circuit board
US11901601B2 (en) 2020-12-18 2024-02-13 Aptiv Technologies Limited Waveguide with a zigzag for suppressing grating lobes
US11949145B2 (en) 2021-08-03 2024-04-02 Aptiv Technologies AG Transition formed of LTCC material and having stubs that match input impedances between a single-ended port and differential ports
US11962085B2 (en) 2021-05-13 2024-04-16 Aptiv Technologies AG Two-part folded waveguide having a sinusoidal shape channel including horn shape radiating slots formed therein which are spaced apart by one-half wavelength
US11973268B2 (en) 2021-05-03 2024-04-30 Aptiv Technologies AG Multi-layered air waveguide antenna with layer-to-layer connections

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2430672A1 (fr) * 1978-07-06 1980-02-01 Lignes Telegraph Telephon Coupleur-detecteur a large bande pour onde millimetrique
DE3431160A1 (de) * 1984-08-24 1986-03-06 ANT Nachrichtentechnik GmbH, 7150 Backnang Gleichspannungs- und hochfrequenzsignalzufuehrung fuer eine diode
US4983933A (en) * 1989-10-05 1991-01-08 Sedco Systems Inc. Waveguide-to-stripline directional coupler

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2829348A (en) * 1952-04-02 1958-04-01 Itt Line-above-ground to hollow waveguide coupling
US2877426A (en) * 1953-02-02 1959-03-10 Itt Microwave transmission lines
US2884601A (en) * 1953-02-02 1959-04-28 Itt Microwave transmission lines
US2979676A (en) * 1957-10-30 1961-04-11 Research Corp Waveguide to microstrip transition structure
US3265995A (en) * 1964-03-18 1966-08-09 Bell Telephone Labor Inc Transmission line to waveguide junction

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2829348A (en) * 1952-04-02 1958-04-01 Itt Line-above-ground to hollow waveguide coupling
US2877426A (en) * 1953-02-02 1959-03-10 Itt Microwave transmission lines
US2884601A (en) * 1953-02-02 1959-04-28 Itt Microwave transmission lines
US2979676A (en) * 1957-10-30 1961-04-11 Research Corp Waveguide to microstrip transition structure
US3265995A (en) * 1964-03-18 1966-08-09 Bell Telephone Labor Inc Transmission line to waveguide junction

Cited By (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3579149A (en) * 1969-12-08 1971-05-18 Westinghouse Electric Corp Waveguide to stripline transition means
US3654572A (en) * 1970-11-05 1972-04-04 Rca Corp Waveguide structure
US3732508A (en) * 1970-12-23 1973-05-08 Fujitsu Ltd Strip line to waveguide transition
US3924204A (en) * 1973-05-07 1975-12-02 Lignes Telegraph Telephon Waveguide to microstrip coupler
US4052683A (en) * 1974-02-28 1977-10-04 U.S. Philips Corporation Microwave device
US3969691A (en) * 1975-06-11 1976-07-13 The United States Of America As Represented By The Secretary Of The Navy Millimeter waveguide to microstrip transition
US4550296A (en) * 1982-05-13 1985-10-29 Ant Nachrichtentechnik Gmbh Waveguide-microstrip transition arrangement
JPH0234002A (ja) * 1988-07-23 1990-02-05 Nec Corp 同軸導波管変換器
US4901040A (en) * 1989-04-03 1990-02-13 American Telephone And Telegraph Company Reduced-height waveguide-to-microstrip transition
US5093640A (en) * 1989-09-29 1992-03-03 Hewlett-Packard Company Microstrip structure having contact pad compensation
EP0458226A2 (de) * 1990-05-22 1991-11-27 CSELT Centro Studi e Laboratori Telecomunicazioni S.p.A. Polarisationsweiche zwischen einem zirkularen Wellenleiter und einem Koaxialkabel
EP0458226A3 (en) * 1990-05-22 1992-11-04 Cselt Centro Studi E Laboratori Telecomunicazioni S.P.A. Orthomode transducer between a circular waveguide and a coaxial cable
JPH0817283B2 (ja) 1990-05-22 1996-02-21 クセルト−セントロ・ステユデイ・エ・ラボラトリ・テレコミニカチオーニ・エツセ・ピー・アー 円形導波管と同軸ケーブルとの間のオルソモード変換器
US20150077198A1 (en) * 2013-09-13 2015-03-19 Toko, Inc. Dielectric Waveguide Resonator and Dielectric Waveguide Filter Using the Same
US10014564B2 (en) * 2013-09-13 2018-07-03 Murata Manufacturing Co., Ltd. Dielectric waveguide resonator and filter comprised of a pair of dielectric blocks having opposing surfaces coupled to each other by a probe
US10992018B2 (en) 2016-07-22 2021-04-27 Mitsubishi Electric Corporation Coaxial-waveguide-to-hollow- waveguide transition circuit
US11670829B2 (en) 2017-02-08 2023-06-06 Aptiv Technologies Limited. Radar assembly with rectangular waveguide to substrate integrated waveguide transition
US10468736B2 (en) * 2017-02-08 2019-11-05 Aptiv Technologies Limited Radar assembly with ultra wide band waveguide to substrate integrated waveguide transition
US10833385B2 (en) * 2017-02-08 2020-11-10 Aptiv Technologies Limited Radar assembly with ultra wide band waveguide to substrate integrated waveguide transition
US11099050B2 (en) * 2017-08-28 2021-08-24 Vega Grieshaber Kg Waveguide coupling for a fill level radar
US20190063983A1 (en) * 2017-08-28 2019-02-28 Vega Grieshaber Kg Waveguide coupling for a fill level radar
US11527808B2 (en) 2019-04-29 2022-12-13 Aptiv Technologies Limited Waveguide launcher
RU2735366C1 (ru) * 2020-02-05 2020-10-30 Акционерное общество "Научно-производственное предприятие "Пульсар" Соосный переход с симметричного полоска на волновод прямоугольного сечения
US11362436B2 (en) 2020-10-02 2022-06-14 Aptiv Technologies Limited Plastic air-waveguide antenna with conductive particles
US11728576B2 (en) 2020-10-02 2023-08-15 Aptiv Technologies Limited Plastic air-waveguide antenna with conductive particles
US11757166B2 (en) 2020-11-10 2023-09-12 Aptiv Technologies Limited Surface-mount waveguide for vertical transitions of a printed circuit board
US11626668B2 (en) 2020-12-18 2023-04-11 Aptiv Technologies Limited Waveguide end array antenna to reduce grating lobes and cross-polarization
US11681015B2 (en) 2020-12-18 2023-06-20 Aptiv Technologies Limited Waveguide with squint alteration
US11901601B2 (en) 2020-12-18 2024-02-13 Aptiv Technologies Limited Waveguide with a zigzag for suppressing grating lobes
US11502420B2 (en) 2020-12-18 2022-11-15 Aptiv Technologies Limited Twin line fed dipole array antenna
US11749883B2 (en) 2020-12-18 2023-09-05 Aptiv Technologies Limited Waveguide with radiation slots and parasitic elements for asymmetrical coverage
US11757165B2 (en) 2020-12-22 2023-09-12 Aptiv Technologies Limited Folded waveguide for antenna
US11444364B2 (en) 2020-12-22 2022-09-13 Aptiv Technologies Limited Folded waveguide for antenna
US11668787B2 (en) 2021-01-29 2023-06-06 Aptiv Technologies Limited Waveguide with lobe suppression
US11721905B2 (en) 2021-03-16 2023-08-08 Aptiv Technologies Limited Waveguide with a beam-forming feature with radiation slots
US11616306B2 (en) 2021-03-22 2023-03-28 Aptiv Technologies Limited Apparatus, method and system comprising an air waveguide antenna having a single layer material with air channels therein which is interfaced with a circuit board
US11962087B2 (en) 2021-03-22 2024-04-16 Aptiv Technologies AG Radar antenna system comprising an air waveguide antenna having a single layer material with air channels therein which is interfaced with a circuit board
US11973268B2 (en) 2021-05-03 2024-04-30 Aptiv Technologies AG Multi-layered air waveguide antenna with layer-to-layer connections
US11962085B2 (en) 2021-05-13 2024-04-16 Aptiv Technologies AG Two-part folded waveguide having a sinusoidal shape channel including horn shape radiating slots formed therein which are spaced apart by one-half wavelength
US11949145B2 (en) 2021-08-03 2024-04-02 Aptiv Technologies AG Transition formed of LTCC material and having stubs that match input impedances between a single-ended port and differential ports

Also Published As

Publication number Publication date
FR1572049A (de) 1969-06-20
NL6810091A (de) 1969-01-21
GB1227559A (de) 1971-04-07
DE1766787B1 (de) 1971-12-23
BE718075A (de) 1968-12-16

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