Optical: systems and elements – Optical modulator
Reexamination Certificate
2002-06-14
2004-06-22
Ben, Loha (Department: 2873)
Optical: systems and elements
Optical modulator
C359S239000, C359S245000, C359S254000, C359S279000, C398S182000, C398S188000, C398S197000, C398S199000, C385S002000, C385S003000, C392S488000
Reexamination Certificate
active
06753992
ABSTRACT:
BACKGROUND OF THE INVENTION
The wavelength response of a Mach-Zehnder intensity modulator plays an important role in the Wavelength Division Multiplexing (WDM) where a single variable or multiple wavelengths may be modulated by a single modulator. The modulator properties relevant to WDM have been investigated. See, V. Poudyal and M. Mezhoudi, “Simultaneous modulation of multiple optical channels with a single Ti:LiNbO3 Mach-Zehnder modulator in a WDM system,”
ICT '
98
International Conference on Telecommunications
, pp. 72-76, 1998, incorporated herein by reference. Similar to WDM, modulator wavelength response plays a key role in Photonic Time Stretch and WDM Sampling techniques currently used for enhancing the performance of Analog-to-Digital Converters (ADC). In these systems, the carrier wavelength is continuously tuned while the modulation is being applied.
Changes in the carrier wavelength shift the modulator bias from the optimum &pgr;/2 bias point and cause a strong increase in the second order distortion. At a certain detuning from the center wavelength, the second order distortion begins to exceed the third order one and therefore, in systems with greater than one octave bandwidth, begins to degrade the Spur Free Dynamic Range (SFDR) of the system. To prevent SFDR degradation due to second order distortion, it is therefore presently necessary to limit the optical bandwidth of the system.
Thus, it would be helpful to be able to extend a modulator response analysis to systems with a chirped carrier. It would also be helpful to be able to provide a technique for second-order distortion suppression that is applicable to all multi-wavelengths systems. Furthermore, it would be helpful to be able to provide a wavelength independent biasing (WEB) technique that allows the optical bandwidth of a system to be extended.
REFERENCES:
patent: 5781327 (1998-07-01), Brock et al.
patent: 6091864 (2000-07-01), Hofmeister
patent: 6122414 (2000-09-01), Shimizu
patent: 6362913 (2002-03-01), Ooi et al.
patent: 6407845 (2002-06-01), Nakamoto
patent: 6580532 (2003-06-01), Yao et al.
L. R. Dalton et al., “From molecules to opto-chips: organic electro-optic materials,”J. Mater. Chem., 1999, 9, 1905-1920.
S. Lee et al., “Demonstration of a Photonically Controlled RF Phase Shifter,”IEEE Microwave and Guided Wave Letters, vol. 9, No. 9, Sep. 1999, 357-359.
H. Erlig et al., “Applications of State-of-the-Art Polymer Modulators,”OSA Conference on Integrated Photonics Research, Monterey, CA, US, Jun. 11-13, 2001.
S. Dubovitsky et al., “Performance of a Mach-Zehnder modulator with a chirped carrier and a novel method for suppression of second order distortion,”DARPA Review, Jun. 17, 2001.
W. Steier et al., “Photonic Assisted A/D: Systems and Spectral Equalization Studies,”DARPA Review, Jun. 17, 2001.
Dubovitsky Serge
Fetterman Harold R.
Michael Joseph
Steier William H.
Ben Loha
Henricks Slavin & Holmes LLP
Pacific Wave Industries, Inc.
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