210 likes | 229 Views
Explore the history, principles, and advancements of fiber optics, the branch of science dealing with light properties and transmission through thin glass threads. Understand the advantages and disadvantages of this technology for efficient data transmission.
E N D
Fiber optics -K.M.Thanvi
What is fiber optics Communication? Optics- The branch of physical science that deals with properties and phenomenon of both visible and invisible light with vision Fiber Optics- The use of very thin glass or plastic threads (i.e. fiber )through which light can travel to carry information
Thus , Fiber-optic communication is a method of transmitting information from one place to another by sending pulses of light through an optical fiber
History --- • Greeks used fire signals in eighth century BC for sending alarm calls for help and announcement of certain events • -During Napoleonic wars in Europe, a French army engineer had designed and developed an optical communication network using light towers built on the hill tops for sending/receiving signals
The Germans had developed a ‘lichtsprecher’-light speaker-for communication for their armed deployments along the Normandy coast while defending allied invasions. • The most significant optical communication system developed came from Alexander graham bell, the inventor of telephone. • This invention of bell was patented under the name photophone, meaning a telephone systems using photons
However the photophone relied on sunlight which is non coherent and hence does not exhibit stabilization. Also it was not possible to operate the system at night or in bad weather condition. • Hence the need for artificial coherent source of optical radiation became necessary. And the problem was solved almost a century later with the advent of laser in 1960 by Theodore H. Maiman. • But even after invention of laser free space transmission was not so efficient due to numerous factors which ultimately lead to the use of guided transmission
Books • Text books • 1. Optical Fiber Communications : Principles and Practices- John M. Senior (PHI) • 2. Optical Fiber and Optical Fiber Communication Systems S. K. Sarkar (S. Chand and Company) • -Reference books • 1. optical fiber communications –Gerd Keiser(Mc Graw Hill ) • 2. optical communication-M MukundaRao(Universities press) • 3. optical fiber communication : principles and systems-A Selvarajan ,s kar, t srinivas(tata mc graw hill)
Optical Fiber • Physically optical fiber is very thin and flexible medium having a cylindrical shape and consisting of three sections • Core • Cladding • Jacket • It is slightly thicker than human hair • It can function as a waveguide or a light pipe to transmit light between two ends of fiber
Advantages • Small in size and weight • Electrical isolation • Immunity to interference and crosstalk • large capacity • Potentially low cost • Greater repeater spacing
Greater bandwidth • Ruggedness and flexibility • Secure transmission • Low transmission loss/attenuation • Abundant availability of raw material • Versatility • Expansion
Disadvantages • Electrical to optical conversion • Right of way • Special installation • Repair • Installation cost • Susceptibility to physical damage