Fiber Optic Wiki

Plastic-clad silica (PCS)

September 4, 2011

These cable types differ with respect to attenuation. Attenuation is principally caused by two physical effects: absorption and scattering.

Fiber-optic cable has two propagation modes: multimode and single mode. They perform differently with respect to both attenuation and time dispersion. The single-mode fiber-optic cable provides much better performance with lower attenuation. To understand the difference between these types, you must understand what is meant by "mode of propagation."

Fiber-Optic Characteristics

September 4, 2011

Optical-fiber systems have many advantages over metallic-based communication systems. These advantages include interference, attenuation, and bandwidth characteristics. Furthermore, the relatively smaller cross section of fiber-optic cables allows room for substantial growth of the capacity in existing conduits. Fiber-optic characteristics can be classified as linear and nonlinear. Nonlinear characteristics are influenced by parameters, such as bit rates, channel spacing, and power levels.

BASIC RESEARCH REMAINS VITAL

September 3, 2011

Amid those fast-paced developments, basic research continued to yield important improvements. In early fiber-optic systems, the amplifiers for regenerating a weak signal constituted a bottleneck. Although optical devices could be used to detect an incoming laser signal, some sort of electronic circuitry was needed to convert it to electric current, amplify the current, and then drive a new laser to recreate the optical signal. This limited the system to the capacity of the electronic amplifiers, which was considerably less than the potential capacity of the lasers and optical fibers.

Fiber-Optic Technologies

September 3, 2011

A Brief History of Fiber-Optic Communications—This section discusses the history of fiber optics, from the optical semaphore telegraph to the invention of the first clad glass fiber invented by Abraham Van Heel. Today more than 80 percent of the world's long-distance voice and data traffic is carried over optical-fiber cables.