Method and system for compensating for optical dispersion in an optical signal

An optical dispersion compensation system operable to receive an optical signal comprising a plurality of channels, wherein the information being communicated in a first set of one or more of the channels is modulated using a first modulation technique and wherein the information being communicated in a second set of one or more of the channels is modulated using a second modulation technique, the system comprising:

• a first dispersion compensation device operable to compensate for optical dispersion in the optical signal such that dispersion compensation for the first set of channels is complete for the first modulation technique and such that dispersion compensation for the second set of channels is incomplete for the second modulation technique;
• a coupler operable to receive the optical signal from the first dispersion compensation device and to split the optical signal into at least a first copy of the optical signal and a second copy of the optical signal;
• a second dispersion compensation device operable to receive the second copy and to perform additional dispersion compensation on the second copy such that dispersion compensation for the second set of channels is complete for the second modulation technique;
• and
• a switch operable to terminate the second set of channels in the first copy of the optical signal and operable to terminate the first set of channels in the second copy of the optical signal.