Wavelength division multiplex optical signal regeneration method

A wavelength division multiplex fiber optic transmission system with a repeater module adapted to be inserted between two optical fiber sections of a wavelength division multiplex fiber optic transmission system including a transmission line comprising:

• N channels at different wavelengths, where N is an integer greater than 1;
• optical amplifiers for amplifying received signal from the transmission line;
• a plurality of optical fiber sections;
• and
• a plurality of repeater modules, each having amplifiers, dispersion compensation fiber and a regenerator;
• wherein said regenerator comprises an optical delay line for each individual channel, a demultiplexer demultiplexing wavelength division multiplexed optical signals into N individual channels and a multiplexer multiplexing optical signals at the output of said N individual channels into multiplexed optical signals;
• wherein each of said delay line introduce a total delay of the length τn″ between the (n+1)th channel and the nth channel so that a time shift of τn between the (n+1)th channel and the nth channel at the output of said regenerator relative to the input of the optical fiber section of the transmission system directly upstream of said regenerator, where τn is greater than zero and includes the delay τn″ and a delay τn′ introduced by a chromatic dispersion in said fiber section.