Patent ID: 7274870
Filing Date: 2007-09-25
Classification: H04B

Abstract:
1. An apparatus for simultaneous channel and optical signal-to-noise ratio monitoring, comprising: a polarization controller being sequentially adjusted to perform polarization control of an optical signal; a dithering signal; a polarization-selective electro-optic modulator receiving said optical signal from said polarization controller and applying said dithering signal to a selective channel, then outputting a dithered optical signal having a single polarization; a beam splitter splitting said dithered optical signal into first and second clusters; a photodetector receiving said first cluster and measuring said optical signal-to-noise ratio; and an optical element receiving said second cluster and monitoring channel wavelength of said dithered optical signal; wherein said polarization controller is sequentially adjusted to switch polarization state of said optical signal for generating a maximal or minimal value at the output of said polarization-selective electro-optic modulator to measure said optical signal-to-noise ratio.