How does the bandwidth of singlemode fiber compare to that of multimode fiber?

Singlemode fiber is designed to carry light directly down the fiber core with minimal dispersion over long distances, allowing for a higher bandwidth compared to multimode fiber. The core of singlemode fiber is much smaller, typically around 8 to 10 micrometers in diameter, which enables only one mode of light to propagate. This results in less modal dispersion, allowing singlemode fibers to transmit data at much higher speeds and over greater distances without significant signal degradation.

In contrast, multimode fiber, with a larger core diameter (ranging from 50 to 62.5 micrometers), can support multiple modes of light traveling through the fiber. While it is effective for short-distance applications, the multiple light paths can lead to modal dispersion, which ultimately limits the bandwidth and distance that multimode fibers can effectively handle.

Therefore, the inherent design of singlemode fiber provides it with a greater bandwidth capability than multimode fiber, making it the preferred choice for long-distance and high-speed data applications.