1 Gbps full-duplex links for ultra-dense-WDM 6.25 GHz frequency slots in optical metro-access networks

Area of Science:

• Optical communications
• Telecommunications engineering
• Photonics

Background:

• Metro-access networks require high-capacity, cost-effective optical links.
• Ultra-dense wavelength division multiplexing (WDM) is crucial for expanding network bandwidth.
• Existing solutions face limitations in terms of cost and user capacity.

Purpose of the Study:

• To demonstrate and optimize 1 Gbps full-duplex optical links for cost-effective metro-access networks.
• To achieve high receiver sensitivity and power budget for robust network performance.
• To evaluate the user capacity of the proposed WDM system.

Main Methods:

• Implementation of 1 Gbps Nyquist-DPSK downlinks using Mach-Zehnder Modulators (MZM).
• Utilization of single-detector heterodyne reception for both downlink and uplink.
• Development of 1 Gbps NRZ-DPSK uplinks with directly phase-modulated Distributed Feedback (DFB) lasers.

Main Results:

• Achieved a receiver sensitivity of -52 dBm for both downlink and uplink.
• Demonstrated a full-duplex link power budget of 43 dB.
• Confirmed the capability to serve 16 (32) users per 100 (200) GHz WDM channel.

Conclusions:

• The proposed 1 Gbps full-duplex optical links are suitable for cost-effective metro-access networks.
• The system offers high sensitivity and a significant power budget, ensuring reliable communication.
• The ultra-dense WDM approach effectively increases user capacity within the network.