Patent ID: 6657779
Filing Date: 2003-12-02
Classification: H04B

Abstract:
A method of determining a launch power of a wavelength division multiplex optical transmission system having an amplified link, comprising the steps of:(a) setting an amplifier power at a beginning of the amplified link; (b) determining a signal-to-noise ratio due to amplified spontaneous emission (OSNRase) and an optical signal-to-noise ratio due to four-wave mixing (OSNRfwm) at an end of the amplified link; (c) comparing each of OSNRase and OSNRfwm with a respective predetermined threshold value; (d) altering the amplifier power; and (e) repeating steps (b), (c) and (d) until the amplifier power is at or near a maximum value while both OSNRase and OSNRfwm exceed the respective predetermined threshold values.