Dynamic gain control by maximum signal power channel in optical linear repeaters for WDM photonic transport networks

The concept of a dynamic gain control method that automatically selects the maximum signal power and keeps it constant is described. This method can cope with not only changes in the number of channels, but also signal power fluctuations. No specific control channel is needed and gain control is active as long as just one signal channel is present. This method's feasibility is confirmed by eight-channel WDM power transient measurements.