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US4081616A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of and apparatus for eliminating the side tone of a telephone station

Assignee: Jeumont Schneider SA
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Filing: 1976-06-09
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Granted: 1978-03-28
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Expires: 1996-06-09
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Abstract

Abstract Method and apparatus for use in telephone exchanges, such as time division multiplex exchanges, for eliminating the side tone of a telephone station by interruption of a restored input signal to a hybrid circuit thereof. A sampled signal is provided to a storage means having an output signal. The storage means output signal is filtered for reconstruction prior to connection to a reception line on the four-wire side of a hybrid circuit. The restored signal is interrupted during moments wherein a transmission signal, output on the four-wire side of the hybrid circuit, is sampled.

Inventors

  • 👤 Alain G. Dumont

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-02 21:35
CPC Classifications
H; H04; H04Q; H04Q11/00; H04Q11/04

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 59 words
A method for eliminating side tones of a telephone station operating in a time-division sampling mode comprising the steps of: (a) receiving signal samples representing a message transmitted by a second station; (b) restoring the transmitted message from the received sampled signals, and (c) interrupting the restored signal at predetermined intervals, thereby removing side tones from said telephone station.
Claim 2
Independent Claim 59 words
A method for eliminating side tones of a telephone station operating in a time-division sampling mode comprising the steps of: (a) receiving signal samples representing a message transmitted by a second station; (b) restoring the transmitted message from the received sampled signals, and (c) interrupting the restored signal at predetermined intervals, thereby removing side tones from said telephone station.
Claim 3
Dependent Claim 25 words
The method recited in claim 1 wherein said restoring step comprises the steps of: (a) storing said received signal and (b) filtering said stored signal.
Claim 4
Dependent Claim 58 words
The method recited in claim 2 wherein said time-division sampling comprises closing a circuit periodically in a transmission path of the telephone station under control of a logic unit, and wherein said interrupting step occurs simultaneously with said periodic closing of a circuit, whereby said telephone station is prevented from receiving its own transmission during said predetermined interval.
Claim 5
Independent Claim 54 words
An apparatus for eliminating side-tones of a telephone station operating in a time-division sampled mode and receiving sampled signals transmitted by a second station, comprising: (a) means for restoring a received sampled signal, said restoring means having an output signal, and (b) switching means for receiving and periodically interrupting said restoring means output signal.
Claim 6
Independent Claim 54 words
An apparatus for eliminating side-tones of a telephone station operating in a time-division sampled mode and receiving sampled signals transmitted by a second station, comprising: (a) means for restoring a received sampled signal, said restoring means having an output signal, and (b) switching means for receiving and periodically interrupting said restoring means output signal.
Claim 7
Dependent Claim 61 words
An apparatus as recited in claim 4 further comprising sampling means in a circuit receiving signals from said telephone station, said sampling means closing a transmission path from said station at predetermined intervals, wherein said switching means interrupts said restoring means output signal during said predetermined intervals, whereby said telephone station does not receive restored signals during intervals of sampled transmission.
Claim 8
Dependent Claim 62 words
An apparatus as recited in claim 5 further comprising a central logic means for controlling said switching means and said sampling means, said central logic means adapted to cause said switching means to interrupt said restoring means output signal and to cause said sampling means to close said transmission path concurrently with the interruption of said output signal by said switching means.
Claim 9
Dependent Claim 28 words
An apparatus as recited in claim 6 comprising a terminating set receiving said output signal of said restoring means through said switching means on a non-grounded reception line.
Claim 10
Dependent Claim 26 words
An apparatus as recited in claim 7 wherein said terminating set provides an output transmission line having a non-grounded wire thereof connected to said sampling means.
Claim 11
Dependent Claim 24 words
An apparatus as recited in claim 6 wherein said restoring means comprises: (a) storage means and (b) filter means connected to said storage means.
Claim 12
Dependent Claim 32 words
An apparatus as recited in claim 6 wherein said switching means comprises a field-effect transistor having a grid, and wherein said central logic means controls said grid for interrupting said output signal.

References Cited (Backward Citations)

US3287499A Cited
US3319005A Cited
US3828146A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-03-27 1981-09-26 1982-03-28 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-03-27 1985-09-26 1986-03-28 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-03-27 1989-09-26 1990-03-28 $7700.00 Window Closed / Lapsed

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