Optical transmission systems of the present invention include at least one
optical amplifier generally including an optical signal amplifying medium supplied
with pump power in the form of optical energy in via an optical pump source. The
pump source includes multiple optical sources, at least two of which provide optical
energy in first and second wavelength ranges separated by a frequency difference.
The amplifier includes a wavelength controller configured to adjust the wavelength
range of at least one of the optical sources to vary the frequency difference in
a manner sufficient to vary optical intensity noise produced when the optical energy
from the multiple optical sources is combined.