Patent ID: 6456425
Filing Date: 2002-09-24
Classification: H01S,H04B

Abstract:
A multiple stage optical amplifying apparatus, comprising:an optical filter to split an optical signal into first and second bands of optical channels, said first band including a first plurality of channels, each at a respective wavelength and said second band including a second plurality of channels, each at a respective wavelength; a first Raman amplifier coupled to said filter, said first Raman amplifier including a gain medium and a pump source, said pump source providing a pump signal at a first pump wavelength to said gain medium; a second Raman amplifier coupled to said filter, said second Raman amplifier including a gain medium and a pump source, said pump source providing a pump signal at a second pump wavelength to said gain medium, wherein said second pump wavelength is outside of said wavelengths associated with said first band; and a combiner optically coupled to said first and second Raman amplifiers configured to combine said amplified first and second bands, wherein each of said first and second Raman amplifiers utilize an associated maximum bandwidth to amplify the maximum number of optical channels for each stage of said multiple stage amplifying apparatus.