Patent ID: 7945161

Claim:
A method of providing power pre-emphasis for N optical channels in a Wavelength Division Multiplex (WDM) signal, each optical channel having a set of one or more characteristics that are representative of the channel, and wherein at least one characteristic is a function of a Bit Error Rate (BER), the method comprising: for each optical channel i in the WDM signal, a) evaluating characteristics for an i th channel and for each channel adjacent to the i th channel; b) comparing the characteristics of the i th channel with the characteristics of the corresponding adjacent channels; c) selecting a predetermined action to be performed on the transmitted power of the i th channel based on the results of the comparison; and d) performing the selected predetermined action on the transmitted power of the i th channel; e) calculating a metric quality function of all of the optical channels based on their transmitted powers as modified by the selected predetermined actions; and f) iteratively repeating steps (a)-(e) until the quality improvement is less than a predetermined figure, or until a predetermined maximum number of iterations is reached.