Patent US4012697A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4012697A Expired / Lapsed US ⏱️ 0.0 years remaining

Clock signal extraction during playback of a self-clocking digital recording

Assignee: Northrop Grumman Innovation Systems LLC
•
Filing: 1975-06-30
•
Granted: 1977-03-15
•
Expires: 1995-06-30
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A clock signal extraction circuit for extracting a clock signal from a reproduced self-clocking digital recording while masking unwanted data transitions from the extracted clock signal. A plurality of input single-shots are selectively operated to produce control signals having respective durations for controlling the gating of a reproduced self-clocking input signal. The gating of the input signal allows only the clock signal transitions in the input signal to be applied to a clock signal output. The single-shots are selected by a comparator circuit which sequentially compares the time of occurrence of the extracted clock signal to each of a plurality of nominal occurrence times equal in number to the number of input single-shots to be controlled thereby.

Inventors

  • 👤 Dale O. Ballinger

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 14:22
CPC Classifications
H; H04; H04L; H04L7/00; H04L7/0054; H04L7/0066; G; G11; G11B; G11B20/00; G11B20/10; G11B20/14; G11B20/1403; G11B20/1407; G11B20/1419

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 386 words
A signal gating circuit comprising: a first signal gating means having a first and a second input circuit and an output circuit, a first plurality of signal generating means arranged to generate a plurality of differing duration output signals, a second signal gating means having a plurality of signal gating circuits equal in number to said plurality of signal generating means with each of said signal gating circuits having a first and a second input and an output circuit connected to a one of said signal generating means, an input terminal, first circuit means connecting said input terminal to said first input of each of said signal gating circuits, second circuit means connecting said input terminal to said second input circuit of said first signal gating means, output terminal means, third circuit means connecting said output circuit of said first signal gating means to said output terminal, fourth circuit means connecting an output of each of said signal generating means to said first input of said first signal gating means, a second plurality of signal generating means arranged to generate a sequence of differing time period output signals in response to an input control signal applied thereto, fifth circuit means arranged to apply an output signal from said output circuit of said first signal gating means as a control signal to said second plurality of signal generating means, comparator means connected to said output circuit of said first signal gating means and to said second plurality of signal generating means for comparing the time of occurrence of an output signal from said output circuit of said first signal gating means with each of said differing time period signals from said second plurality of signal generating means and for producing an output signal representative of a match between said output signal from said output circuit of first signal gating means and said differing time period signals, and third signal gating means arranged to apply said output signal from said comparator means to said second input of a selected one of said second signal gating means as determined by the match between the signals compared by said comparator means to control an output signal from a respective one of said first plurality of signal generating means for application to said first input of said first signal gating means.
Claim 2
Dependent Claim 386 words
A signal gating circuit comprising: a first signal gating means having a first and a second input circuit and an output circuit, a first plurality of signal generating means arranged to generate a plurality of differing duration output signals, a second signal gating means having a plurality of signal gating circuits equal in number to said plurality of signal generating means with each of said signal gating circuits having a first and a second input and an output circuit connected to a one of said signal generating means, an input terminal, first circuit means connecting said input terminal to said first input of each of said signal gating circuits, second circuit means connecting said input terminal to said second input circuit of said first signal gating means, output terminal means, third circuit means connecting said output circuit of said first signal gating means to said output terminal, fourth circuit means connecting an output of each of said signal generating means to said first input of said first signal gating means, a second plurality of signal generating means arranged to generate a sequence of differing time period output signals in response to an input control signal applied thereto, fifth circuit means arranged to apply an output signal from said output circuit of said first signal gating means as a control signal to said second plurality of signal generating means, comparator means connected to said output circuit of said first signal gating means and to said second plurality of signal generating means for comparing the time of occurrence of an output signal from said output circuit of said first signal gating means with each of said differing time period signals from said second plurality of signal generating means and for producing an output signal representative of a match between said output signal from said output circuit of first signal gating means and said differing time period signals, and third signal gating means arranged to apply said output signal from said comparator means to said second input of a selected one of said second signal gating means as determined by the match between the signals compared by said comparator means to control an output signal from a respective one of said first plurality of signal generating means for application to said first input of said first signal gating means.
Claim 3
Dependent Claim 41 words
A signal gating circuit as set forth in claim 1 wherein said comparator means sequentially compares said output signal from said output circuit of said first signal gating means with each of said differing time period signals in a predetermined order.
Claim 4
Dependent Claim 30 words
A signal gating circuit as set forth in claim 1 wherein said first plurality of signal generating means each includes a monostable multivibrator for producing a predetermined duration output signal.
Claim 5
Dependent Claim 34 words
A signal gating circuit as set forth in claim 1 wherein said second plurality of signal generating means includes a plurality of monostable multivibrators arranged to produce said plurality of differing time period signals.
Claim 6
Dependent Claim 37 words
A signal gating circuit as set forth in claim 4 wherein said first plurality of signal generating means is equal in number to the number of said monostable multivibrators in said second plurality of signal generating means.
Claim 7
Dependent Claim 61 words
A signal gating circuit as set forth in claim 5 wherein said comparator means includes a plurality of AND gate means with each of said AND gate means being arranged to sum said output signals from said first signal gating means with an output signal from a respective one of said monostable multivibrators in said second plurality of signal generating means.
Claim 8
Dependent Claim 46 words
A single gating circuit as set forth in claim 6 wherein said third signal gating means includes a plurality of signal storage means with each of said signal storage means having an output connected to an input of a corresponding one of said AND gate means.
Claim 9
Dependent Claim 39 words
A signal gating circuit as set forth in claim 7 wherein each of said signal storage means has an output connected to said second input of a corresponding one of said signal gating circuits in said second gating means.
Claim 10
Dependent Claim 20 words
A signal gating circuit as set forth in claim 7 wherein each of said signal storage means is a flip-flop.
Claim 11
Independent Claim 91 words
A method of gating a signal including the steps of comparing the time of occurrence of the signal with each of a plurality of differing period signals, producing an output signal corresponding to a match between the compared signals, applying the output signal to a respective one of a plurality of signal generating means to produce a corresponding duration output signal and applying the signal to be gated and said lastmentioned output signal to a gate circuit to control the gating of the signal to be gated through said gate circuit.
Claim 12
Independent Claim 91 words
A method of gating a signal including the steps of comparing the time of occurrence of the signal with each of a plurality of differing period signals, producing an output signal corresponding to a match between the compared signals, applying the output signal to a respective one of a plurality of signal generating means to produce a corresponding duration output signal and applying the signal to be gated and said lastmentioned output signal to a gate circuit to control the gating of the signal to be gated through said gate circuit.

References Cited (Backward Citations)

US3663883A Cited
US3602828A Cited
US3609560A Cited
US3894246A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-03-14 1980-09-13 1981-03-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-03-14 1984-09-13 1985-03-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-03-14 1988-09-13 1989-03-15 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag