Patent ID: 6414775
Filing Date: 2002-07-02
Classification: H04B

Abstract:
A method for determining the gain profile of a path through an optical amplifier disposed in a first optical transmission path of an optical transmission system supporting bi-directional communication between first and second terminals along the first optical transmission path and a second optical transmission path, said method comprising the steps of:a. generating a supervisory optical tone at a given wavelength within the bandwidth of the optical amplifier; b. modulating the wavelength of the optical tone about said given wavelength; c. transmitting from the first terminal said modulated optical tone along the first optical transmission path and through the optical amplifier; d. receiving a portion of the modulated optical tone after it traverses the optical amplifier and performing FM to AM conversion thereon to form an amplitude modulated optical tone; e. transmitting said amplitude modulated optical tone to the first terminal along the second transmission path via optical loop-back path; f. repeating steps (a)-(e) for a plurality of different wavelengths to obtain gain measurements associated with said different wavelengths that constitute said gain profile.