US5696707A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of measuring the noise level in the presence of a signal
Assignee: Agilent Technologies Inc
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Filing: 1995-04-10
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Granted: 1997-12-09
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Expires: 2015-04-10
Abstract
Abstract A method and apparatus for measuring the noise level in an optical amplifier in the presence of a signal at a signal wavelength. The signal is detuned to a second wavelength different from the signal wavelength. A difference function corresponding to the difference in noise levels before and after detuning of the signal as a function of wavelength is determined. The noise level at the signal wavelength is measured. The value of the difference function at the signal wavelength is added to the noise level measured in the previous step.
Inventors
- 👤 Christian Hentschel
- 👤 Emmerich Mueller
- 👤 Clemens Rueck
- 👤 Edgar Leckel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:10
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/07; H04B10/073; H04B10/0731; H01; H01S; H01S3/00; H01S3/0014; H04B10/29; H04B10/291; H04B10/2912; H01S2301/00; H01S2301/02
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
88 words
A method of measuring the noise level in the presence of a signal at a signal wavelength, comprising the steps of: a) detuning the signal to a second wavelength different from the signal wavelength; b) determining a difference function corresponding to the difference in noise levels before and after detuning of the signal as a function of wavelength; c) measuring the noise level at the signal wavelength; and d) adding the value of the difference function at the signal wavelength to the noise level measured in step c.
Claim 2
Independent Claim
88 words
A method of measuring the noise level in the presence of a signal at a signal wavelength, comprising the steps of: a) detuning the signal to a second wavelength different from the signal wavelength; b) determining a difference function corresponding to the difference in noise levels before and after detuning of the signal as a function of wavelength; c) measuring the noise level at the signal wavelength; and d) adding the value of the difference function at the signal wavelength to the noise level measured in step c.
Claim 3
Dependent Claim
21 words
The method as in claim 1 wherein the value of the difference function at the signal wavelength is determined by interpolation.
Claim 4
Dependent Claim
21 words
The method as in claim 1 wherein the value of the difference function at the signal wavelength is determined by approximation.
Claim 5
Dependent Claim
61 words
The method as in claim 1 wherein the step of determining the difference function includes the steps of: i) measuring the noise levels of the curve representing the optical intensity variation before detuning at several wavelengths; and ii) measuring the noise levels of the curve representing the optical intensity variation after detuning at the same wavelengths as in step i), respectively.
Claim 6
Dependent Claim
34 words
The method of measuring as set forth in claim 1 wherein the noise level in the presence of a signal is a noise level in the presence of a signal in an optical amplifier.
Claim 7
Dependent Claim
14 words
The method of claim 5 wherein the optical amplifier is an erbium-doped fiber amplifier.
Claim 8
Independent Claim
99 words
An apparatus for measuring a noise level in the presence of a signal at a signal wavelength, comprising: a) means for detuning the signal to a second wavelength different from the signal wavelength; b) means for determining a difference function corresponding to a difference in noise levels before and after detuning of the signal as a function of wavelength by said means for detuning; c) means for measuring the noise level at the signal wavelength; and d) means for adding the value of the difference function at the signal wavelength to the noise level measured by said measuring means.
Claim 9
Independent Claim
99 words
An apparatus for measuring a noise level in the presence of a signal at a signal wavelength, comprising: a) means for detuning the signal to a second wavelength different from the signal wavelength; b) means for determining a difference function corresponding to a difference in noise levels before and after detuning of the signal as a function of wavelength by said means for detuning; c) means for measuring the noise level at the signal wavelength; and d) means for adding the value of the difference function at the signal wavelength to the noise level measured by said measuring means.
Claim 10
Dependent Claim
22 words
The apparatus as in claim 7 further including an interpolator for determining the value of the difference function at the signal wavelength.
Claim 11
Dependent Claim
23 words
The apparatus as in claim 7 further including means for determining the value of the difference signal at the signal wavelength by approximation.
Claim 12
Dependent Claim
67 words
The apparatus as in claim 7 wherein said means for determining a difference function includes: i) means for measuring the noise levels of the curve representing the optical intensity variation before detuning at several wavelengths by said means for detuning; and ii) means for measuring the noise levels of the curve representing the optical intensity variation after detuning by said means for detuning at said several wavelengths.
Claim 13
Dependent Claim
30 words
The apparatus as in claim 7 wherein the noise level in the presence of a signal is a noise level in the presence of a signal in an optical amplifier.
Claim 14
Dependent Claim
15 words
The apparatus as in claim 11 wherein the optical amplifier is an erbium-doped fiber amplifier.
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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) | 2000-12-08 | 2001-06-09 | 2001-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2004-12-08 | 2005-06-09 | 2005-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2008-12-08 | 2009-06-09 | 2009-12-09 | $7700.00 | Window Closed / Lapsed |