High-security space division multiplexing optical transmission scheme based on constellation grid selective twisting.

Area of Science:

• Optical Communications
• Information Security
• Chaos Theory

Background:

• Space division multiplexing (SDM) is crucial for increasing optical network capacity.
• Existing encryption methods may not meet the stringent security demands of high-capacity systems.
• Multicore, few-mode fibers offer significant potential for future optical networks.

Purpose of the Study:

• To propose and experimentally validate a high-security optical transmission scheme for multicore, few-mode systems.
• To enhance the security of PDM-16QAM signals using chaotic encryption.
• To achieve ultra-high net transmission rates and capacity-distance products.

Main Methods:

• Implementing a constellation grid selective twisting technique for encryption.
• Utilizing the Rossler chaos model to encrypt PDM-16QAM signals.
• Employing XOR function and constellation map rotation for enhanced security.
• Experimentally verifying the scheme in a 19-core, 4-mode fiber with 80-wave multiplexing.

Main Results:

• Achieved a net transmission rate of 34.13 Tbit/s over 6000 km with PDM-QPSK modulation.
• Achieved a net transmission rate of 68.27 Tbit/s over 1000 km with PDM-16QAM modulation.
• Demonstrated a large key space of 10^101 and high sensitivity of the chaotic model's initial value (10^-16 to 10^-17).

Conclusions:

• The proposed chaotic encryption scheme is effective for high-security optical transmission.
• The system is compatible with high-capacity SDM systems, offering a promising solution for next-generation networks.
• This approach significantly enhances both security and capacity in optical communication systems.