摘要 |
<p>There is provided a method for determining an in-band noise parameter, such as the Optical Signal-to-Noise Ratio (OSNR), on an optical signal-under-test (SUT) propagating along an optical communication link and comprising a data-carrying signal contribution of any arbitrary degree of polarization and a noise contribution. A spectral shape trace of signal contribution in the SUT is estimated using a reference optical spectrum trace of a reference signal which comprises a signal contribution that is spectrally representative of the signal contribution of the SUT and a noise contribution which is at least approximately known. The signal contribution is mathematically discriminated from said noise contribution in the SUT using the spectral shape trace and the test optical spectrum trace. The in-band noise parameter is then determined at least from the mathematically discriminated noise contribution.</p> |