Last time I have discussed the various losses and their reasons in optical fibers. Toady we will discuss the various applications of fibers.
Optical Fibre Communication System
Optical fibers are mainly used in communication systems due to rapidly increasing demands for telephone communications throughout the world, multiconductor copper cables have become not only very expensive but also an inefficient way to meet these information requirements.
The frequency limitations in the copper system make a conducting medium for high speed communications necessary. The optical fibre, with its low weight and high frequency characteristics (approximately 40 GHz) and its imperviousness to interference from electromagnetic radiation, has become the choice for all heavy demand long-line telephone communication systems.
An optical fibre communication system is similar in basic concept to any type of general communication system. We may know that the communication in fibers is based on the basic principle of total internal reflection. The function of which is to convey the signal from the information source over the transmission medium to the destination. The communication system, therefore, consists of a transmitter or modulator linked to the information source, the transmission medium and a receiver or demodulator at the destination point. It must be kept in mind that in any trannsmission medium (wires, co-axial cables, free space etc.), the signal is attenuated and is subjected to the degradations due to the contamination by random signals and noise as well as distortions imposed by mechanisms within the medium itself. Therefore, in any communication system there is a maximum permitted distance between the transmitter and the receiver beyond which the system effectively ceases to give intelligible communication.
This is one of the major applications of fiber communication systems.