Transmission system and method for equalization of channels in the system

The invention is related to a method for equalizing performance of traffic channels in a WDM system where means for controlling transmitters ( 12 ), amplifiers ( 38 ) and receivers ( 14 ) are provided. Potentially, a number of channels are defined as loading channels ( 100 ). The method follows the steps of measuring the optical power at the input ( 48 ) of the amplifier ( 38 ), setting the power levels of a predefined number of loading channels ( 100 ) to a high power level, setting the power level of the traffic channels ( 200 ) to a power level less then the power level of the loading channels ( 100 ), adjusting the power level of the traffic channels ( 200 ), adjusting the power level of the loading channels ( 100 ), stabilizing the sum of the optical power measured at the optical amplifier ( 38 ), continuing the process for each channel the receiver lock signal ( 75 ) is sent back to the transmitters.