Optical communications – Transmitter – Having particular modulation
Reexamination Certificate
2008-04-29
2008-04-29
Chan, Jason (Department: 2613)
Optical communications
Transmitter
Having particular modulation
Reexamination Certificate
active
07366425
ABSTRACT:
Different techniques for generating spectrally efficient carrier-suppressed modulated optical signals, also known as “phase-shaped binary transmission” (PSBT) signals, employ electrical components that generate only 2-level or binary signals, in contrast to techniques that require 3-level electrical drivers. The PSBT modulators can be used with return-to-zero (RZ) modulators for generating RZ-PSBT signals, which have the characteristic of even greater spectral efficiency than NRZ PSBT signals. The technique is generalized to RZ signals with an arbitrary phase difference between pulses. These signals can be generated by shifting the central (carrier) frequency of an RZ modulated optical signal, which can be done using a certain phase modulation or using spectral filtering with a passband offset from the center (carrier) frequency of the modulated optical signal, and the signals can also be generated by phase modulation at a frequency lower than the signaling rate of the modulated signal.
REFERENCES:
patent: 2002/0196508 (2002-12-01), Wei et al.
Winzer et al. (P.J. Winzer and J. Leuthold, “Return-to-zero modulator using a single NRZ drive single and an optical delay interferometer”, IEEE Photonics Tech Lett, vol. 13, Dec. 2001, pp. 1298-1300).
Pennickx et al. (D. Pennickx et al. “Optical differential phase shift keying (DPSK) direct detection considered as a duobinary signal”, Proc. ECOC 2001, 2001, pp. 456-457).
Esman et al., “Wideband Efficiency Improvement of Fiber Optic Systems by Carrier Subtraction”, IEEE Photonics Technology Letters, vol. 7, No. 2, Feb. 1995.
Modulations Formats Research at COM, “New Modulation Formats in Optical Communications”, http://www.com.dtu.dk/research/style...search—areas/modulation—formats.html, Jan. 24, 2003.
Liu Fenghai
Mamyshev Pavel V.
Mikkelsen Benny P.
Rasmussen Christian J.
Chan Jason
Mintera Corporation
Wang Quan-Zhen
Weingarten Schurgin, Gagnebin & Lebovici LLP
LandOfFree
Methods and apparatus for spectrally efficient optical... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Methods and apparatus for spectrally efficient optical..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods and apparatus for spectrally efficient optical... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2768257