OSNR monitoring technique based on orthogonal delayed-homodyne method

Abstract

The authors propose and demonstrate a simple technique to monitor the optical signal-to-noise ratio (OSNR) of wavelength-division-multiplexing (WDM) signals using the orthogonal delayed-homodyne method. This technique estimates the OSNR by analyzing the receiver noise characteristics after eliminating the signal components at a specific frequency within the modulation bandwidth. The results show that the OSNR of WDM signals could be monitored with accuracy better than 0.5 dB in the range of 12 35 dB.