OPTICAL TRANSMISSION LINK INCORPORATING HIGHPASS OPTICAL FILTERING

摘要

An optical fiber transmission link with reduced channel depletion due t o stimulated Raman scattering is formed by including a high pass optical filte r in the transmission fiber. The filter may comprise one or more discrete components, or may be formed as a "distributed" filter along the length of the optical fiber. T he cut-off frequency for the high pass optical filter is selected to be immediately bel ow the frequency of the input channel to be transmitted. When used in an arrangemen t with multiple input channels, the cut-off frequency is controlled to be immediate ly below the lowest input channel frequency.