Fault-detection technique in a WDM-PON

Area of Science:

• Optical Engineering
• Telecommunications
• Network Fault Detection

Background:

• Passive optical networks (PONs) are crucial for broadband access.
• Wavelength division multiplexing (WDM) enhances capacity in PONs.
• In-service fault localization is vital for network reliability.

Purpose of the Study:

• To introduce a novel in-service fault localization method for WDM-PONs.
• To demonstrate the effectiveness of the proposed technique in identifying fiber faults.
• To ensure minimal disruption to existing network traffic.

Main Methods:

• Utilized a tunable Optical Time Domain Reflectometer (OTDR).
• Employed a wavelength-locked Fabry-Perot laser diode for OTDR realization.
• Tested fault detection on both feeder and drop fiber segments.

Main Results:

• Successfully detected faults in both feeder and drop fibers.
• Achieved a fault localization resolution of 100 meters.
• Obtained a dynamic range of 12 dB for fault detection.
• Confirmed negligible crosstalk between OTDR signals and transmission data.

Conclusions:

• The proposed method enables effective in-service fault localization in WDM-PONs.
• The technique offers practical advantages in terms of resolution and dynamic range.
• The method ensures the integrity of transmission data during fault detection.