Patent ID: 7020092

Claim:
A method for channel-specific adjustment of power levels of associated transmitted signals in an optical wavelength-division multiplex transmission system to achieve one of equal signal power levels and equal signal-to-noise ratios of received individual signals, the method comprising: determining transmission characteristics for each transmission channel; determining a transmission-end maximum permissible dynamic range; determining, on a channel-specific basis, signal power levels of the associated transmitted signals; and if the maximum permissible dynamic range at the transmission end is exceeded: determining individual power discrepancies of the transmitted signal power levels from a mean signal power level of the signals at the transmission end; calculating a transmission compression factor in compliance with the maximum permissible dynamic range, the mean signal power and maximum signal power discrepancies, the compression factor being equal for all transmitted signals; recalculating new signal power levels from the individual power discrepancies and the compression factor, such that a permissible reception-end maximum dynamic range is complied with; and setting newly calculated compression power levels of the transmitted signals; calculating a transmission-end correction factor from a ratio of a previous transmission-end mean level value to a transmission-end mean level value from a new transmitted signal power level; and changing the individual signal power levels of transmitted signals using the transmission-end correction factor, which is equal for all transmitted signals.