Tunable multimode wavelength division multiplex raman pump and amplifier, and a system, method, and computer program product for controlling tunable raman pumps, and raman amplifiers

A method for operating a tunable Raman amplifier for amplifying a WDM optical signal in an amplification medium, comprising steps of:

• emitting light from a tunable multimode pump source, said light having multiple longitudinal modes with a center wavelength;
• receiving said light in an optical fiber aligned to receive the light from the pump source;
• coupling the light to the amplification medium so as to amplify an optical signal propagating therethrough;
• and
• tuning said multimode pump source so as to change said center wavelength to another center wavelength.

A tunable Raman amplifier for amplifying a WDM optical signal in an amplification medium, comprising:

• means for emitting light having multiple longitudinal modes with a center wavelength;
• means for receiving said light in an optical fiber aligned to receive the light;
• means for coupling the light to the amplification medium so as to amplify an optical signal propagating therethrough;
• and
• means for tuning said means for emitting so as to change said center wavelength to another center wavelength.

An automated Raman amplifier design method, comprising the steps of:

• emitting first light from a first tunable multimode pump source, said first light having multiple longitudinal modes with a first center wavelength;
• emitting second light from a second tunable multimode pump source, said second light having multiple longitudinal modes with a second center wavelength,
• coupling the first light and the second light to an amplification medium so as to amplify an optical signal propagating therethrough;
• monitoring an output of said Raman amplifier, said output being at least one of a signal level and a gain profile across a predetermined amplification bandwidth in the amplification medium;
• performing a FFT on said output so as to obtain an FFT result;
• comparing said FFT result with a performance profile, and determining if at least a spectral portion of a difference between said FFT result and said performance profile is greater than a predetermined amount;
• and
• tuning said multimode pump source so as to change said center wavelength to another center wavelength such that a corresponding Raman gain will compensate for said difference to within said predetermined amount.