Patent US5115217A successfully refreshed from Google Patents.
← Back to Patent Explorer
US5115217A Expired / Lapsed US ⏱️ 0.0 years remaining

RF tuning element

Assignee: California Institute of Technology
•
Filing: 1990-12-06
•
Granted: 1992-05-19
•
Expires: 2010-12-06
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A device for tuning a circuit includes a substrate, a transmission line on the substrate that includes first and second conductors coupled to a circuit to be tuned, and a movable short-circuit for varying the impedance the transmission line presents to the circuit to be tuned. The movable short-circuit includes a dielectric layer disposed atop the transmission line and a distributed shorting element in the form of a conductive member that is configured to be slid along at least a portion of the transmission line atop the dielectric layer. The conductive member is configured to span the first and second conductors of the transmission line and to define at least a first opening that spans the two conductors so that the conductive member includes first and second sections separated by the first opening. The first and second sections of the conductive member combine with the first and second conductors of the transmission line to form first and second low impedance sections of transmission line, and the opening combines with the first and second conductors of the transmission line and the dielectric layer to form a first high impedance section of transmission line intermediate the first and second low impedance sections. Each of the first low impedance section and the first high impedance section have a length along the transmission line of approximately one-quarter wavelength, thus providing a periodic variation of transmission line impedance. That enhances reflection of rf power.

Inventors

  • 👤 William R. McGrath
  • 👤 Victor M. Lubecke

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 17:57
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/24; H01P1/28; H01P5/00; H01P5/04

Claims Analysis

Total Claims: 18
Claim 1
Independent Claim 247 words
A device for tuning a circuit, comprising: a substrate, a transmission line on the substrate that includes first and second conductors coupled to a circuit to be tuned, and means defining a movable short-circuit for varying the impedance the transmission line presents to the circuit to be tuned; the means defining a movable short-circuit including a dielectric layer disposed atop the transmission line and a distributed shorting element in the form of a conductive member that is configured to be slid along at least a portion of the transmission line atop the dielectric layer; the conductive member being configured to span the first and second conductors of the transmission line and to define at least a first opening that spans the two conductors so that the conductive member includes first and second sections separated by the first opening; the first and second sections of the conductive member combining with the first and second conductors of the transmission line and the dielectric layer to form first and second low impedance sections of transmission line, and the opening combining with the first and second conductors of the transmission line to form a first high impedance section of transmission line intermediate the first and second low impedance sections; and at least each of the first low impedance section and the first high impedance section having a length along the transmission line of approximately one-quarter wavelength, thus providing a periodic variation of transmission line impedance that enhances reflection of rf power.
Claim 2
Independent Claim 247 words
A device for tuning a circuit, comprising: a substrate, a transmission line on the substrate that includes first and second conductors coupled to a circuit to be tuned, and means defining a movable short-circuit for varying the impedance the transmission line presents to the circuit to be tuned; the means defining a movable short-circuit including a dielectric layer disposed atop the transmission line and a distributed shorting element in the form of a conductive member that is configured to be slid along at least a portion of the transmission line atop the dielectric layer; the conductive member being configured to span the first and second conductors of the transmission line and to define at least a first opening that spans the two conductors so that the conductive member includes first and second sections separated by the first opening; the first and second sections of the conductive member combining with the first and second conductors of the transmission line and the dielectric layer to form first and second low impedance sections of transmission line, and the opening combining with the first and second conductors of the transmission line to form a first high impedance section of transmission line intermediate the first and second low impedance sections; and at least each of the first low impedance section and the first high impedance section having a length along the transmission line of approximately one-quarter wavelength, thus providing a periodic variation of transmission line impedance that enhances reflection of rf power.
Claim 3
Dependent Claim 31 words
A device as recited in claim 1, wherein the conductive member includes a rectangularly shaped plate of conductive material and the first opening is a rectangularly shaped opening in the plate.
Claim 4
Dependent Claim 180 words
A device as recited in claim 1, wherein: the conductive member defines a second opening that spans the first and second conductors of the transmission line so that the conductive member includes first, second, and third sections such that the first and second sections are separated by the first opening and the second and third sections are separated the second opening; the first, second, and third sections of the conductive member combine with the first and second conductors of the transmission line and the dielectric layer to form first, second, and third low impedance sections of transmission line, and the first and second openings combine with the first and second conductors of the transmission line to form first and second high impedance sections of transmission line intermediate the first, second, and third low impedance sections; and at least each of the first and second low impedance sections and the first and second high impedance sections have a length along the transmission line approximately one-quarter wavelength, thus providing a periodic variation of transmission line impedance that enhances reflection of rf power.
Claim 5
Dependent Claim 32 words
A device as recited in claim 1, wherein the conductive member includes a rectangularly shaped plate of conductive material and the first and second openings are rectangularly shaped openings in the plate.
Claim 6
Dependent Claim 33 words
A device as recited in claim 1, wherein: each of the first low impedance section and the first high impedance section have a length along the transmission line that is approximately one-quarter wavelength.
Claim 7
Dependent Claim 17 words
A device as recited in claim 1, wherein the transmission line is a coplanar strip transmission line.
Claim 8
Dependent Claim 25 words
A device as recited in claim 1, further comprising means for guiding the conductive member as the conductive member is moved along the transmission line.
Claim 9
Dependent Claim 14 words
A device as recited in claim 1, wherein the transmission line is a slotline.
Claim 10
Independent Claim 154 words
A device for tuning a circuit, comprising: a substrate; a transmission line on the substrate, which transmission line is coupled to a circuit to be tuned; and means defining a movable short-circuit for varying the impedance the transmission line presents to the circuit to be tuned; the movable short-circuit including a conductive member that is configured to be moved to any of various locations along the transmission line and to provide a low impedance path across the transmission line at any such location to which it is moved; wherein the transmission line is configured as a coplanar strip transmission line having first and second conductors separated by a space; the substrate defines a slot in alignment with the space; and the conductive member includes a protrusion configured to extend intermediate the first and second conductors into the slot in order to reduce the impedance of the low impedance path provided by the conductive member.
Claim 11
Independent Claim 154 words
A device for tuning a circuit, comprising: a substrate; a transmission line on the substrate, which transmission line is coupled to a circuit to be tuned; and means defining a movable short-circuit for varying the impedance the transmission line presents to the circuit to be tuned; the movable short-circuit including a conductive member that is configured to be moved to any of various locations along the transmission line and to provide a low impedance path across the transmission line at any such location to which it is moved; wherein the transmission line is configured as a coplanar strip transmission line having first and second conductors separated by a space; the substrate defines a slot in alignment with the space; and the conductive member includes a protrusion configured to extend intermediate the first and second conductors into the slot in order to reduce the impedance of the low impedance path provided by the conductive member.
Claim 12
Independent Claim 169 words
A device for tuning a circuit, comprising: a substrate; a transmission line on the substrate, which transmission line is coupled to a circuit to be tuned; and means defining a movable short-circuit for varying the impedance the transmission line presents to the circuit to be tuned; the movable short-circuit including a conductive member that is configured to be moved to any of various locations along the transmission line and to provide a low impedance path across the transmission line at any such location to which it is moved; and the movable short circuit also including means for guiding the conductive member as the conductive member is moved along the transmission line; wherein the conductive member includes a plate of conductive material that is configured to be slid along the transmission line; and the means for guiding the conductive member includes two guide-rail structures mounted on the substrate that extend along opposite sides of the transmission line in order to retain the conductive member in alignment with the transmission line.
Claim 13
Independent Claim 169 words
A device for tuning a circuit, comprising: a substrate; a transmission line on the substrate, which transmission line is coupled to a circuit to be tuned; and means defining a movable short-circuit for varying the impedance the transmission line presents to the circuit to be tuned; the movable short-circuit including a conductive member that is configured to be moved to any of various locations along the transmission line and to provide a low impedance path across the transmission line at any such location to which it is moved; and the movable short circuit also including means for guiding the conductive member as the conductive member is moved along the transmission line; wherein the conductive member includes a plate of conductive material that is configured to be slid along the transmission line; and the means for guiding the conductive member includes two guide-rail structures mounted on the substrate that extend along opposite sides of the transmission line in order to retain the conductive member in alignment with the transmission line.
Claim 14
Dependent Claim 52 words
A device as recited in claim 10, wherein the conductive member is configured to provide a first low impedance section of transmission line followed by a first high impedance section of transmission line and a second low impedance section of transmission line followed by a second high impedance section of transmission line.
Claim 15
Dependent Claim 102 words
A planar circuit, comprising: a substrate, a planar antenna circuit on the substrate, and means defining an adjustable tuning element on the substrate for tuning the planar antenna circuit; the adjustable tuning element including a transmission line on the substrate that is coupled to the planar antenna circuit and a conductive member that is configured to be moved to any of various locations along the transmission line in order to provide a low impedance path across the transmission line at any such location to which it is moved; wherein the planar antenna circuit includes a planar antenna and a SIS junction device.
Claim 16
Dependent Claim 102 words
A planar circuit, comprising: a substrate, a planar antenna circuit on the substrate, and means defining an adjustable tuning element on the substrate for tuning the planar antenna circuit; the adjustable tuning element including a transmission line on the substrate that is coupled to the planar antenna circuit and a conductive member that is configured to be moved to any of various locations along the transmission line in order to provide a low impedance path across the transmission line at any such location to which it is moved; wherein the planar antenna circuit includes a planar antenna and a SIS junction device.
Claim 17
Dependent Claim 18 words
A circuit as recited in claim 12, wherein the adjustable tuning element is configured as a shunt tuner.
Claim 18
Dependent Claim 19 words
A circuit as recited in claim 13, further comprising a second adjustable tuning element configured as a series tuner.

References Cited (Backward Citations)

US2543721A Cited
US2752499A Cited
US2961620A Cited
US2915717A Cited
US3421118A Cited
US3405375A Cited
US4096453A Cited
US4955085A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1995-05-19 1995-11-18 1996-05-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1999-05-19 1999-11-18 2000-05-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2003-05-19 2003-11-18 2004-05-19 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag