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US5237290A Expired / Lapsed US ⏱️ 0.0 years remaining

Method and apparatus for clock recovery

Assignee: Nokia Bell Labs
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Filing: 1992-05-08
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Granted: 1993-08-17
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Expires: 2012-05-08
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Abstract

Abstract A method and apparatus for recovering the phase of a signal which may change at periodic intervals is disclosed which comprises gated variable frequency oscillators. These results are obtained in an illustrative embodiment of the present invention in which an incoming signal is fed into a gated oscillator and the complement of the incoming signal is fed into a matching gated oscillator. Advantageously, the respective outputs of the two oscillators are fed into a Boolean NOR gate. When the gated oscillators are designed to oscillate at the frequency of the incoming signal, the output waveform will have a bounded phase relationship with respect to the incoming signal.

Inventors

  • 👤 Mihai Banu
  • 👤 Alfred E. Dunlop

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 13:08
CPC Classifications
H; H04; H04L; H04L7/00; H04L7/02; H04L7/033; H03; H03K; H03K5/00; H03L; H03L7/00; H03L7/06; H03L7/08; H03L7/0807; H04L7/027; H04L7/0276

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 67 words
A method of creating a periodic signal which has a bounded phase relationship with respect to an input signal comprising the steps of: operative on said input signal above a first threshold, generating a first oscillatory signal; operative on said input signal below a second threshold, generating a second oscillatory signal; and generating said periodic signal based on said first oscillatory signal and said second oscillatory signal.
Claim 2
Independent Claim 67 words
A method of creating a periodic signal which has a bounded phase relationship with respect to an input signal comprising the steps of: operative on said input signal above a first threshold, generating a first oscillatory signal; operative on said input signal below a second threshold, generating a second oscillatory signal; and generating said periodic signal based on said first oscillatory signal and said second oscillatory signal.
Claim 3
Dependent Claim 31 words
The method of claim 1 wherein said step of generating said periodic signal comprises the step of forming the Boolean NOR of said first oscillatory signal and said second oscillatory signal.
Claim 4
Dependent Claim 31 words
The method of claim 1 wherein said step of generating said periodic signal comprises the step of forming the Boolean NAND of said first oscillatory signal and said second oscillatory signal.
Claim 5
Dependent Claim 33 words
The method of claim 1 further comprising the step of adjusting the frequency of said first oscillatory signal and said second oscillatory signal to coincide with the frequency of a reference periodic waveform.
Claim 6
Dependent Claim 25 words
The method of claim 4 wherein a phase-locked loop is used to adjust the frequency of said first oscillatory signal and said second oscillatory signal.
Claim 7
Independent Claim 72 words
An apparatus for creating a periodic signal which has a bounded phase relationship with respect to an input signal, said apparatus comprising: means, operative on said input signal above a first threshold, for generating a first oscillatory signal; means, operative on said input signal below a second threshold, for generating a second oscillatory signal; and means for generating said periodic signal based on said first oscillatory signal and said second oscillatory signal.
Claim 8
Independent Claim 72 words
An apparatus for creating a periodic signal which has a bounded phase relationship with respect to an input signal, said apparatus comprising: means, operative on said input signal above a first threshold, for generating a first oscillatory signal; means, operative on said input signal below a second threshold, for generating a second oscillatory signal; and means for generating said periodic signal based on said first oscillatory signal and said second oscillatory signal.
Claim 9
Dependent Claim 18 words
The apparatus of claim 6 wherein said means for generating said periodic signal comprises a Boolean NOR gate.
Claim 10
Dependent Claim 18 words
The apparatus of claim 6 wherein said means for generating said periodic signal comprises a Boolean NAND gate.
Claim 11
Dependent Claim 32 words
The apparatus of claim 6 further comprising means for adjusting the frequency of said first oscillatory signal and said second oscillatory signal to coincide with the frequency of a reference periodic signal.
Claim 12
Dependent Claim 34 words
The apparatus of claim 6 further comprising a phase-locked loop for adjusting the frequency of said first oscillatory signal and said second oscillatory signal to coincide with the frequency of a reference periodic signal.

References Cited (Backward Citations)

US3893042A Cited
US4567448A Cited
US4891598A Cited
US5134637A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1996-08-16 1997-02-15 1997-08-17 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 2000-08-16 2001-02-15 2001-08-17 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2004-08-16 2005-02-15 2005-08-17 $7700.00 Window Closed / Lapsed

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