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US4638272A Expired / Lapsed US ⏱️ 0.0 years remaining

Lossy transmission line using spaced ferrite beads

Assignee: Department of Defence
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Filing: 1984-05-04
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Granted: 1987-01-20
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Expires: 2004-05-04
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Abstract

Abstract PCT No. PCT/AU84/00076 Sec. 371 Date Jan. 2, 1085 Sec. 102(e) Date Jan. 2, 1985 PCT Filed May 4, 1984 PCT Pub. No. WO84/04426 PCT Pub. Date Nov. 8, 1984.A lossy transmission line in which the effective length of the line is reduced by providing resistive ferrite beads spaced along the line to provide constant power loss per unit length. Inductance ferrite beads may be included equally spaced along the line. Resistive beads are located with increasing frequency per unit length from the beginning of the line until a maximum bead density per unit length is achieved. The lossy line is suitable as a terminating unit for a portable travelling wave antenna and in other situations where size reduction is desirable.

Inventors

  • 👤 Richard A. Ive

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 06:27
CPC Classifications
H; H01; H01P; H01P1/00; H01P1/24; H01P1/26

Claims Analysis

Total Claims: 10
Claim 1
Independent Claim 67 words
A lossy transmission line comprising a conducting wire threaded with resistive ferrite beads which exhibits substantially constant power loss per unit length, and wherein the resistive ferrite beads are distributed sparsely at the beginning of the wire with frequency of distribution increasing to a maximum per unit length which is related to the size of the beads and the available space per unit length of the wire.
Claim 2
Dependent Claim 67 words
A lossy transmission line comprising a conducting wire threaded with resistive ferrite beads which exhibits substantially constant power loss per unit length, and wherein the resistive ferrite beads are distributed sparsely at the beginning of the wire with frequency of distribution increasing to a maximum per unit length which is related to the size of the beads and the available space per unit length of the wire.
Claim 3
Dependent Claim 28 words
a lossy transmission line as claimed in claim 1 which includes both resistive and inductance ferrite beads along its length separated from each other by non conductive spacers.
Claim 4
Dependent Claim 23 words
A lossy transmission line as claimed in claim 2 wherein the inductance ferrite beads are evenly distributed along the length of the wire.
Claim 5
Dependent Claim 31 words
A lossy transmission line as claimed in claim 1 wherein the spacing of the resistive beads increases exponentially to a maximum which is determined by the available space per unit length.
Claim 6
Dependent Claim 35 words
A lossy transmission line as claimed in claim 4 wherein inductance ferrite beads are also threaded on said wire and are evenly distributed along its length and all beads are separated by non conductive spacers.
Claim 7
Dependent Claim 55 words
A lossy transmission line comprising a stainless steel wire threaded with ferrite inductance beads evenly distributed along its length and ferrite resistive beads which increase exponentially in distribution along its length from the beginning of the wire up to a maximum distribution per unit length which is determined by the available space per unit length.
Claim 8
Dependent Claim 55 words
A lossy transmission line comprising a stainless steel wire threaded with ferrite inductance beads evenly distributed along its length and ferrite resistive beads which increase exponentially in distribution along its length from the beginning of the wire up to a maximum distribution per unit length which is determined by the available space per unit length.
Claim 9
Dependent Claim 19 words
A lossy transmission line as claimed in claim 6 wherein the ferrite beads are separated by non conductive spacers.
Claim 10
Dependent Claim 25 words
A lossy transmission line as claimed in claim 7 wherein the threaded wire, the beads and the spacers are enclosed in an hermetically sealed tube.

References Cited (Backward Citations)

US1900962A Cited
US2228797A Cited
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EP0087371A2 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-01-19 1990-07-21 1991-01-20 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-01-19 1994-07-21 1995-01-20 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-01-19 1998-07-21 1999-01-20 $7700.00 Window Closed / Lapsed

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