US5373389A
Expired / Lapsed
US
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Method for linearizing an unbalanced Mach Zehnder optical frequency discriminator
Assignee: Ciena Corp
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Filing: 1992-10-27
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Granted: 1994-12-13
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Expires: 2012-10-27
Abstract
Abstract An unbalanced Mach Zehnder optical frequency discriminator is linearized to suppress third order nonlinear distortion. An optical carrier that is modulated in optical frequency is input to an unbalanced Mach Zehnder interferometer to discriminate RF information signals carried on the carrier. The Mach Zehnder interferometer has an adjustable operating point. The operating point is adjusted to a point where the output intensity of the Mach Zehnder interferometer is no more than about ten percent of its maximum value. In order to avoid problems with second order distortion, the optical carrier is modulated with RF signals that do not occupy more than a single octave. The operating point of the device can be adjusted by adjusting an electrical bias thereof, by adjusting the wavelength of the optical carrier, or by adjusting the temperature of the device.
Inventors
- 👤 David R. Huber
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 19:57
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/60; H04B10/66; H04B10/67; H04B10/676; G; G02; G02F; G02F2203/00; G02F2203/19
Claims Analysis
Total Claims: 21
Claim 1
Independent Claim
91 words
A method for linearizing an unbalanced Mach Zehnder optical frequency discriminator to suppress third order nonlinear distortion when demodulating information from a frequency modulated optical carrier, comprising the steps of: inputting an optical carrier that is modulated in optical frequency to an unbalanced Mach Zehnder interferometer to discriminate RF information signals carried on said carrier, said Mach Zehnder interferometer having an adjustable operating point; and adjusting said operating point to a point where the output intensity of said Mach Zehnder interferometer is no more than about 10% of its maximum value.
Claim 2
Independent Claim
91 words
A method for linearizing an unbalanced Mach Zehnder optical frequency discriminator to suppress third order nonlinear distortion when demodulating information from a frequency modulated optical carrier, comprising the steps of: inputting an optical carrier that is modulated in optical frequency to an unbalanced Mach Zehnder interferometer to discriminate RF information signals carried on said carrier, said Mach Zehnder interferometer having an adjustable operating point; and adjusting said operating point to a point where the output intensity of said Mach Zehnder interferometer is no more than about 10% of its maximum value.
Claim 3
Dependent Claim
32 words
A method in accordance with claim 1 wherein the operating point of said Mach Zehnder interferometer is adjusted to a point where the output intensity is about 5% of its maximum value.
Claim 4
Dependent Claim
25 words
A method in accordance with claim 1 wherein said optical carrier is modulated with RF signals that do not occupy more than a single octave.
Claim 5
Dependent Claim
17 words
A method in accordance with claim 3 wherein said optical carrier is modulated only in optical frequency.
Claim 6
Dependent Claim
17 words
A method in accordance with claim 1 wherein said optical carrier is modulated only in optical frequency.
Claim 7
Dependent Claim
26 words
A method in accordance with claim 1 wherein said adjusting step comprises the step of electrically biasing said Mach Zehnder interferometer to set said operating point.
Claim 8
Dependent Claim
32 words
A method in accordance with claim 6 wherein the operating point of said Mach Zehnder interferometer is adjusted to a point where the output intensity is about 5% of its maximum value.
Claim 9
Dependent Claim
25 words
A method in accordance with claim 6 wherein said optical carrier is modulated with RF signals that do not occupy more than a single octave.
Claim 10
Dependent Claim
17 words
A method in accordance with claim 8 wherein said optical carrier is modulated only in optical frequency.
Claim 11
Dependent Claim
17 words
A method in accordance with claim 6 wherein said optical carrier is modulated only in optical frequency.
Claim 12
Dependent Claim
28 words
A method in accordance with claim 1 wherein said adjusting step comprises the step of adjusting the temperature of said Mach Zehnder interferometer to set said operating point.
Claim 13
Dependent Claim
32 words
A method in accordance with claim 11 wherein the operating point of said Mach Zehnder interferometer is adjusted to a point where the output intensity is about 5% of its maximum value.
Claim 14
Dependent Claim
25 words
A method in accordance with claim 11 wherein said optical carrier is modulated with RF signals that do not occupy more than a single octave.
Claim 15
Dependent Claim
17 words
A method in accordance with claim 13 wherein said optical carrier is modulated only in optical frequency.
Claim 16
Dependent Claim
17 words
A method in accordance with claim 11 wherein said optical carrier is modulated only in optical frequency.
Claim 17
Dependent Claim
27 words
A method in accordance with claim 1 wherein said adjusting step comprises the step of adjusting the frequency of said optical carrier to set said operating point.
Claim 18
Dependent Claim
32 words
A method in accordance with claim 16 wherein the operating point of said Mach Zehnder interferometer is adjusted to a point where the output intensity is about 5% of its maximum value.
Claim 19
Dependent Claim
25 words
A method in accordance with claim 16 wherein said optical carrier is modulated with RF signals that do not occupy more than a single octave.
Claim 20
Dependent Claim
17 words
A method in accordance with claim 18 wherein said optical carrier is modulated only in optical frequency.
Claim 21
Dependent Claim
17 words
A method in accordance with claim 16 wherein said optical carrier is modulated only in optical frequency.
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