Digital subcarrier multiplexing for flexible spectral allocation in optical transport network

Area of Science:

• Optical Communications
• Digital Signal Processing
• Telecommunications Engineering

Background:

• Optical transport networks require efficient spectral utilization and flexible data rate management.
• Digital Subcarrier Multiplexing (DSCM) offers a promising approach for enhancing optical communication systems.

Purpose of the Study:

• To demonstrate a spectrally efficient Digital Subcarrier Multiplexed (DSCM) coherent optical system.
• To investigate the flexibility in bandwidth allocation and scalability in data rate granularity.
• To explore the dynamic adaptability of the receiver for varying DSCM channel configurations.

Main Methods:

• Digitally generating mutually orthogonal subcarrier channels.
• Implementing a coherent optical system architecture.
• Experimentally transmitting data using a 22.2 Gb/s DSCM system with 10 Quadrature Phase Shift Keying (QPSK) modulated subcarrier channels.

Main Results:

• Demonstrated a spectrally efficient DSCM system with flexible bandwidth allocation.
• Achieved dynamic receiver configuration for varying numbers of DSCM channels.
• Investigated the performance impacts of channel spacing and time mismatch in a 10-channel, 22.2 Gb/s QPSK system.

Conclusions:

• The proposed DSCM system offers high flexibility and scalability for optical transport networks.
• The system's receiver can adapt dynamically without reconfiguration.
• Further analysis of channel spacing and time mismatch is crucial for optimizing performance.