Optical communications – Multiplex – Broadcast and distribution system
Reexamination Certificate
2006-12-12
2006-12-12
Robertson, David (Department: 2192)
Optical communications
Multiplex
Broadcast and distribution system
C398S026000, C398S033000
Reexamination Certificate
active
07149428
ABSTRACT:
The present invention provides a method and an apparatus for monitoring optical signal to noise ratio (OSNR) in a wavelength division multiplexing optical transmission system. The present invention utilizes a polarization nulling method and a tunable optical bandpass filter in order to reliably monitor the OSNR by considering a finite polarization nulling ratio, polarization mode dispersion and non-linear birefringence of the optical system in real time measurement of the OSNR. Further, the tunable optical bandpass filter is controlled to filter all wavelength bands of wavelength division multiplexed signals. Since the invention may monitor a plurality of demultiplexed optical signals with a single apparatus, the overall cost of the OSNR monitoring equipment is significantly reduced.
REFERENCES:
patent: 5223705 (1993-06-01), Aspell et al.
patent: 5917649 (1999-06-01), Mori et al.
patent: 6040933 (2000-03-01), Khaleghi et al.
patent: 8384956 (2002-05-01), Shieh
patent: 6678431 (2004-01-01), Han et al.
patent: 6952529 (2005-10-01), Mittal
Chung Yun Chur
Kim Chul Han
Shin Seung Kyun
Graybeal Jackson Haley LLP
Jean-Bart Ralph
Robertson David
Teralink Communications, Inc.
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