Patent EP0146833A2 successfully refreshed from Google Patents.
Patent US4135064A successfully refreshed from Google Patents.
US4135064A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Impedance compensation of transmission line
Assignee: Nortel Networks Ltd
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Filing: 1977-08-15
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Granted: 1979-01-16
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Expires: 1997-08-15
Abstract
Abstract An unconditionally stable impedance matching network for matching a nonloaded voice frequency transmission line to the standard impedance of a repeater on said line is provided.
Inventors
- 👤 Nachum Lichtenstein
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 10:34
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/16; H04B3/40
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
128 words
An impedance matching network for a repeatered non-loaded voice frequency transmission line comprising, in combination: a first pair of terminals for connection to a repeater; a second pair of terminals for connection to said transmission line; means for introducing two effective series resistances at predetermined frequencies one each between each of said first and second pairs of terminals without substantially affecting d-c current flow; passive impedance means coupled across said second pair of terminals; and a negative impedance converter for converting the impedance of a series connection of a resistor, a capacitor and an inductor, the converter impedance being a-c coupled across said second pair of terminals; whereby said impedance matching network matches the impedance of said transmission line to the impedance of said repeater while maintaining stability.
Claim 2
Dependent Claim
128 words
An impedance matching network for a repeatered non-loaded voice frequency transmission line comprising, in combination: a first pair of terminals for connection to a repeater; a second pair of terminals for connection to said transmission line; means for introducing two effective series resistances at predetermined frequencies one each between each of said first and second pairs of terminals without substantially affecting d-c current flow; passive impedance means coupled across said second pair of terminals; and a negative impedance converter for converting the impedance of a series connection of a resistor, a capacitor and an inductor, the converter impedance being a-c coupled across said second pair of terminals; whereby said impedance matching network matches the impedance of said transmission line to the impedance of said repeater while maintaining stability.
Claim 3
Dependent Claim
56 words
The impedance matching network of claim 1, said means for introducing two effective resistances being a balanced transformer on a single core having two separate secondary windings, one in series with the TIP conductor and the other in series with the RING conductor of said transmission line, and a primary winding having a resistor connected thereacross.
Claim 4
Dependent Claim
25 words
The impedance matching network of claim 2, said active impedance means being coupled across said second pair of terminals by means of an isolation transformer.
Claim 5
Dependent Claim
23 words
The impedance matching network of claim 3, said passive impedance means being a series connection of a resistor, a capacitor and an inductor.
Claim 6
Dependent Claim
14 words
The impedance matching network of claim 3, said repeater being a negative impedance repeater.
Claim 7
Dependent Claim
23 words
The impedance matching network of claim 2, said passive impedance means being a series connection of a resistor, a capacitor and an inductor.
Claim 8
Dependent Claim
14 words
The impedance matching network of claim 2, said repeater being a negative impedance repeater.
Claim 9
Dependent Claim
23 words
The impedance matching network of claim 1, said passive impedance means being a series connection of a resistor, a capacitor and an inductor.
Claim 10
Dependent Claim
14 words
The impedance matching network of claim 1, said repeater being a negative impedance repeater.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-01-15 | 1982-07-17 | 1983-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-15 | 1986-07-17 | 1987-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-15 | 1990-07-17 | 1991-01-16 | $7700.00 | Window Closed / Lapsed |