Last mile access-based FSO and VLC systems

Area of Science:

• Optical Communications
• Wireless Networking
• Telecommunications Engineering

Background:

• Free-space optics (FSO) and visible light communication (VLC) present viable alternatives to traditional last-mile access solutions.
• Each technology offers unique advantages such as high bandwidth, low latency, and cost-effectiveness, but also has limitations.

Purpose of the Study:

• To propose and evaluate hybrid FSO/VLC systems for enhanced last-mile access.
• To address the individual shortcomings of FSO and VLC by integrating their strengths.
• To explore advanced techniques like Wavelength Division Multiplexing (WDM) and Non-Orthogonal Multiple Access (NOMA) for improved performance.

Main Methods:

• Design and simulation of three distinct hybrid FSO/VLC scenarios using Optisystem and Matlab.
• Implementation of Pulse Amplitude Modulation with four levels (PAM-4) for data transmission.
• Evaluation of system performance under various conditions, including different turbulence and weather scenarios.

Main Results:

• Achieved outdoor link distances exceeding 10 km and indoor coverage of approximately 2 m.
• Demonstrated a high data rate of 10 Gbps with a low bit-error rate (BER) of 1.5×10^-32.
• Confirmed the feasibility of achieving target data rates with reduced FSO distances under adverse environmental conditions.

Conclusions:

• Hybrid FSO/VLC systems effectively overcome the limitations of standalone technologies for last-mile connectivity.
• The proposed scenarios, incorporating WDM and NOMA, show significant potential for high-capacity and multi-user communication.
• The system demonstrates robust performance suitable for diverse environmental challenges, paving the way for reliable optical wireless communication networks.