| 摘要 |
A method of measuring the noise level in the presence of a signal (51) at a signal wavelength ( lambda signal), comprises the steps of detuning the signal (51) to a second wavelength different from the signal wavelength, determining a difference function (Delta ( lambda )) corresponding to the difference in noise levels before and after detuning of the signal as a function of wavelength, measuring the noise level (N* ( lambda signal)) at the signal wavelength ( lambda signal), and adding the value of the difference function (Delta) at the signal wavelength ( lambda signal) to the noise level (N* ( lambda signal)) measured in the previous step. The method is particularly suited for measuring the noise level in an optical amplifier. <IMAGE> |
