
converted to amplitude fluctuations in the presence of dispersion. The one-pump
parametric delay scheme is illustrated in Figure 20.55(a); an input signal (
s
)is
converted to the idler wavelength (
i
) and transmitted through the dispersive line
(DL). The second-stage process converts the idler back to the original wavelength,
resulting in an optical delay, which is the product of the wavelength shift (
i
–
s
)
and the total dispersion.
The pump phase modulation required to suppress Brillouin scatteri ng in the
HNLF, results in excessive idler broad ening, and is illustrated in Figure 20.55(b).
In practice, an efficient FPC device requires a modulation ...