Optical performance monitoring technique using software-based synchronous amplitude histograms

Area of Science:

• Optical communications engineering
• Signal processing
• Metrology

Background:

• Accurate monitoring of optical signal-to-noise ratio (OSNR) and chromatic dispersion (CD) is crucial for maintaining high-performance optical networks.
• Existing methods like asynchronous amplitude histogram (AAH) can be affected by signal transient characteristics, limiting their accuracy.

Purpose of the Study:

• To propose and demonstrate a novel software-based synchronous amplitude histogram (SAH) technique for simultaneous OSNR and CD monitoring.
• To evaluate the performance and robustness of the SAH technique against signal transients.

Main Methods:

• Development of a software-based synchronization technique to construct SAHs from asynchronously sampled signal intensities.
• Accurate extraction of OSNR and CD parameters from the center of the symbol using SAHs.
• Experimental validation using 10-Gbaud Quadrature Phase-Shift Keying (QPSK) and Quadrature Amplitude Modulation (QAM) signals.

Main Results:

• The proposed SAH technique accurately monitors both OSNR and CD over wide ranges.
• The SAH method demonstrates robustness against the transient characteristics of modulated signals.
• Performance is validated for 10-Gbaud QPSK and QAM signals.

Conclusions:

• The software-based SAH analysis offers a simple yet effective method for simultaneous OSNR and CD monitoring in optical systems.
• This technique overcomes limitations of previous methods by being insensitive to signal transients.
• The SAH approach enhances the reliability of optical network monitoring.