Performance analysis of a hybrid DWDM-FSO system for 6G

Abstract The increasing demand for higher bandwidth and reliable communication networks driven by next-generation mobile technologies (5G/6G) and the Internet of Things (IoT) poses challenges for existing communication infrastructures. Free Space Optics (FSO) offers high-speed wireless data transmission comparable to fiber optics but suffers from significant performance degradation due to environmental factors such as rain, fog, and atmospheric turbulence. This study investigates the potential of a hybrid Dense Wavelength Division Multiplexing (DWDM)-FSO system to overcome these challenges. By combining DWDM’s high capacity with the flexibility of FSO links, the system achieves a data rate of 5.4 Tbps across 90 users. Simulations conducted using OptiSystem software evaluate the impact of different weather conditions – clear skies, heavy rain, and dense fog – on performance. Key metrics, including bit error rate (BER), quality factor (Q-factor), and eye diagrams, are analyzed to assess signal integrity and reliability. A comparative study of Single Input Single Output (SISO) and MIMO configurations (2 × 2 and 3 × 3) shows that the 3 × 3 MIMO-FSO setup significantly enhances performance, maintaining signal quality and extending range under adverse weather. These findings highlight the hybrid DWDM-FSO system’s potential to deliver high-speed, resilient communication, ensuring seamless connectivity in dynamic environments.