Spread spectrum for covert communication in ultra-violet communication system

Area of Science:

• Optical Communications
• Signal Processing
• Information Security

Background:

• Covert communication is crucial for secure data transmission.
• Ultra-violet (UV) communication offers potential for stealthy transmissions.
• Existing methods often rely on detectable pilot sequences, compromising covertness.

Purpose of the Study:

• To develop a covert communication scheme for ultra-violet systems.
• To enhance security by avoiding pilot sequence transmission.
• To evaluate the performance and covertness of the proposed spread spectrum approach.

Main Methods:

• Characterization of the ultra-violet communication system model.
• Implementation of Warden for monitoring legitimate user transmissions using binary hypothesis and Kolmogorov-Smirnov tests.
• Proposal of a blind synchronization approach to eliminate pilot sequence transmission.
• System-level simulations and experimental evaluations.

Main Results:

• The spread spectrum approach achieves low detection bit error rate.
• The scheme demonstrates effective covertness, even under weak light intensity.
• Experimental validation confirms the detection performance and covertness.

Conclusions:

• The proposed spread spectrum scheme provides a viable method for covert ultra-violet communication.
• Blind synchronization significantly improves the covertness of the system.
• The approach is robust under challenging environmental conditions like weak light.