Question

What determines the capacity of an optical fibre strand?

Answer 1

Fiber optics popularity is increasing. Fiber optic replaces copper cable as a way of communication. It transfers information from one place to another by sending pulses through optical fiber. Fiber optics have lower attenuation and interference as compared to copper wire, hence, has a advantage in long distance and high demand communication.

The capacity of the fiber optic is determined by the fiber type. Fiber can be identified by the type of path that the light rays or modes travel with in the fiber core. Fiber are basically two types: Single mode fiber and multimode fiber. The single mode fiber has a higher capacity and capability than multimode fiber type. Example: undersea telecommunication cables which uses single mode, can convey 60k voice channels on a pair of single mode fiber.

The basic elements of fiber optic are: Core, cladding and coating. Core is the area where light transmission takes place. The larger the core the more light can be transmitted from the fiber. Cladding is to provide lower refractive index at the core interface in order to cause reflection through the core. Coating is a multilayer of plastic that is applied to preserve fiber strength, absorb shock and provide extra protection.