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US4800518A Expired / Lapsed US ⏱️ 0.0 years remaining

Differential correlator circuit

Assignee: Racal Data Communications Inc
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Filing: 1985-06-21
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Granted: 1989-01-24
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Expires: 2005-06-21
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Abstract

Abstract A differential correlator for a receiver including a voltage controlled current source which is controlled by an input data signal which is based on a received signal. A switching circuit selectively couples the controlled current to one of two storage capacitors as a function of a reference signal. A comparison circuit compares the integrated voltages on the storage capacitors at the end of each integration period T to provide user data as a function of the comparison. A discharge circuit discharges the storage capacitors to a common initial voltage after the integrated voltages are compared.

Inventors

  • 👤 William J. Miller

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 08:23
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/12; G06G7/19; G06G7/1928; G06G7/1935

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 129 words
A correlation detection circuit comprising: means responsive to an input data signal for providing a controlled signal as a function of the input data signal; first and second storage means for selectively integrating said controlled signal and for providing first and second integration signals; switching means responsive to a single reference signal for selectively coupling said controlled signal to said first and second storage means as a function of the reference signal, said switching means including differentially coupled transistors having their emitters coupled together for receiving said controlled signal and having respective collectors respectively coupled to said first and second storage means; and comparator means responsive to said first and second integration signals for providing a comparator output indicative of the difference between said first and second integration signals.
Claim 2
Dependent Claim 129 words
A correlation detection circuit comprising: means responsive to an input data signal for providing a controlled signal as a function of the input data signal; first and second storage means for selectively integrating said controlled signal and for providing first and second integration signals; switching means responsive to a single reference signal for selectively coupling said controlled signal to said first and second storage means as a function of the reference signal, said switching means including differentially coupled transistors having their emitters coupled together for receiving said controlled signal and having respective collectors respectively coupled to said first and second storage means; and comparator means responsive to said first and second integration signals for providing a comparator output indicative of the difference between said first and second integration signals.
Claim 3
Dependent Claim 160 words
A correlation detection circuit comprising: input means responsive to an input data signal for providing a controlled signal as a function of the input data signal; and differential integrating means for integrating said controlled signal as a function of a single two-state reference signal over a period T and for providing an integration output indicative of the difference between integration when said reference signal is in a first state and integration when said reference signal is in a second state, said differential integrating means including: (a) first and second accumulating means selectively responsive to said controlled signal and for providing first and second integration signals as said integration output; and (b) switching means responsive to the two-state reference signal for coupling said controlled signal to said first accumulating means in response to the first state of the reference signal and for coupling said controlled signal to said second accumulating means in response to the second state of the reference signal.
Claim 4
Dependent Claim 160 words
A correlation detection circuit comprising: input means responsive to an input data signal for providing a controlled signal as a function of the input data signal; and differential integrating means for integrating said controlled signal as a function of a single two-state reference signal over a period T and for providing an integration output indicative of the difference between integration when said reference signal is in a first state and integration when said reference signal is in a second state, said differential integrating means including: (a) first and second accumulating means selectively responsive to said controlled signal and for providing first and second integration signals as said integration output; and (b) switching means responsive to the two-state reference signal for coupling said controlled signal to said first accumulating means in response to the first state of the reference signal and for coupling said controlled signal to said second accumulating means in response to the second state of the reference signal.
Claim 5
Dependent Claim 40 words
The correlation detection circuit of claim 2 wherein said differential integrating means further includes: comparator means responsive to said first and second integration signals for providing a logical output indicative of the difference between said first and second integration signals.
Claim 6
Dependent Claim 141 words
A correlation detection circuit for receiving an input data signal and a single reference signal, comprising: a voltage controlled current source responsive to the input data signal for providing a variable current as a function of the input data signal; and means for differentially integrating said variable current over a period T as a function of the reference signal to provide a differential integration output indicative of the correlation between the input data signal and the reference signal, said differentially integrating means including: (a) first and second accumulating means selectively responsive to said variable and for providing first and second integration signals as said differential integration output; and (b) switching means responsive to the reference signal for coupling said variable to said first accumulating means or to said second accumulating means as a function of the value of the reference signal.
Claim 7
Dependent Claim 141 words
A correlation detection circuit for receiving an input data signal and a single reference signal, comprising: a voltage controlled current source responsive to the input data signal for providing a variable current as a function of the input data signal; and means for differentially integrating said variable current over a period T as a function of the reference signal to provide a differential integration output indicative of the correlation between the input data signal and the reference signal, said differentially integrating means including: (a) first and second accumulating means selectively responsive to said variable and for providing first and second integration signals as said differential integration output; and (b) switching means responsive to the reference signal for coupling said variable to said first accumulating means or to said second accumulating means as a function of the value of the reference signal.
Claim 8
Dependent Claim 41 words
The correlation detection circuit of claim 4 wherein said means for differentially integrating further includes: comparator means responsive to said first and second integration signals for providing a logical output indicative of the difference between said first and second integration signals.

References Cited (Backward Citations)

US2645755A Cited
US3076933A Cited
US3982114A Cited
US3256426A Cited
US3333091A Cited
US3478268A Cited
US4209834A Cited
US3700876A Cited
US3906213A Cited
US4317204A Cited
US4164628A Cited
US4149121A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-01-24 1992-07-25 1993-01-24 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-01-24 1996-07-25 1997-01-24 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-01-24 2000-07-25 2001-01-24 $7700.00 Window Closed / Lapsed

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