ABSTRACT
FIBRE-OPTICS COMMUNICATION
Most reference materials that discuss the historical perspective mention about Indian smoke signals. None of these primitive systems was secure due to the spreading of the unguided light. Ideally, a communication system should be secure and should not require installation of a cumbersome physical media. Fiber optics satisfied these desires, and as early as 1958, fiber-optic equipment was being focused for use in the factory. The fiber-optic cable is an important element in the fiber-optic link. Today, in comparison to the early 1970s, the performance of fiber-optic cable in terms of bandwidth and attenuation is far superior to any electrical cable of similar cost. Some consider it a problem of fiber optics that the electronics of the fiber-optic transceivers are unreliable. This is a false, in that the electronics have the same life as any of the other electronic components used in a network. The need for sharing components or modules is the same for fiber optics as for any other critical factory-level electronics. Optical fiber is used as glass or plastic, to contain and guide light wave.
The fiber cable does not transmit electrical current, so it cannot cause ground loops. Therefore ground differentials caused by lightning-induced transients do not affect the communication cable. This characteristic is quite an advantage because lightning strikes are a common phenomenon. A typical fiber-optic cable can allow up to 200 million bits per second (MBS), while a high-quality coaxial cable is required to achieve the same data rate, but can cover only shorter distances. The reduction in the number of repeaters is a prime reason for the telephone companies increasing use of fiber optics. Many control applications require the operator to perform normal duties in the vicinity of high voltages. The use of fiber allows isolation of the high voltage from the operators. An advantage of fiber-optics is that the