Increasing Fiber Capacity with L-band Options

This white paper discusses methods for increasing fiber capacity using L-band technology. It outlines three approaches: Conventional C + L-band, Extended C-band + Shifted L-band, and Extended C-band + Extended L-band. Each method is evaluated based on performance, sustainability, supply chain, and cost considerations. The Conventional C + L-band option serves as a baseline, providing 9.6 THz of usable spectrum. The Extended C-band + Shifted L-band increases capacity to 10.8 THz but introduces performance penalties due to higher noise levels. The Extended C-band + Extended L-band further expands capacity to 12 THz, yet also faces similar challenges. The paper emphasizes the importance of evaluating real-world performance and the environmental impact of these technologies, particularly regarding power consumption and sustainability. It concludes that while newer options offer more spectrum, they may not significantly enhance usable capacity compared to the established Conventional C + L-band solution, which remains the most efficient choice for network providers.