Chirp-Managed Directly-Modulated DFB Laser

We review recent patents on a chirp managed transmitter comprised of a DML and the subsequent optical bandpass filter. Large dispersion tolerance of this transmitter is realized by chirp control through the phase correlation between adjacent bits for the destructive interference in order to erase the power of “0” bits and enhance the extinction ratio. The reach of this transmitter without dispersion compensation is superior to the best reported DML-based and duobinary transmitters. The results show that this is a promising solution to meet the size, power, capacity and cost requirements of the optical links simultaneously in the today and tomorrow's metro and access networks.