Question

Please answer 4 question, tks

2.Explain the concept of total internal reflection and how it is important in optical communications.

3.Discuss the differences between single mode, multimode and graded index fibres.

6.What is meant by attenuation in optical fibers?

7.State the two ways in which energy is lost along the length of an optical fiber.

Answer 1

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impostant in ophical Commuai cation be cqure. OCCur be cause Electromagnetic interfesence light is propagated is vesy high. 3and width Co3)SPeedis veay high Tate tyansfes data

classiicati on Foc Si gle mo de Step ind en Fíber. muhmad e muimode s aded index RIbee mode imdicates poopaation a th Sinsle gkep mode Indea ste masio w secH on ie Cooe muihmade tep in d n rerachve indea Refpactive imder poo6le paro e is in ter omat .

Simsle mode step 1ndem The a o t PTO1AD attng hoocgh cor e is ve ess mateaial Th e vequiced Teceiues semcitive moe kike tases is Teqwired mote dire cive ffght So s ce dispes sion Puise will O CCS mot mdem mulh mo de Step sPoebearef move O ght fsopagatirg is The amomt The oft mo1a Poasea 21 fr anot eq us a eo e Ceives Cemsitive more at the liaht fous ce Com be wsed Lases dan and o Ccus will dispa ion pusse disadv)s) g7aded inden Fibe ns e ovu come fulse diepearion To Indea fibe,.. о97aded muimode occu in 9raded indez dispa sion putse and the co mpler melh o d manufacturing The cables othe is vay high whem compare cott 2 M- hue V NoTmalized cut ott reg modes mo.ok The mulh роoрадонтg mode teP Indn Hbe o the cotte DE mel moda ore ati on Fo Single VE TD n2a VE 2.405 TD CN A

Attenuation in Fiber ophic is the lo Ss Of In ten sity energy when Signal tranimitfed in long distance Th ere th at ar e many fact oTs attenuahon cause

losses Fibes in a due to AbsOTHon (ossec асcия These loster material cote the in impasities paecemt mpurity atome Clight energy ir absOTbed y impuxiy atoms csh emev e the light ao afom th e impunity the Sikes photon tie chasge em esa casjeer omd ase fo ote energ, lere) from move enes n fave does not reach fho oihur end of Cabl e and is con siderd aj los

Scattesing losiei . These losses also dve to imparihes a ccuss matesial CO e present I the photon enaa e Subhicient is not to move ne chasge Cosanes Lwel Co s catt esed the light ovmo thes level will popa4ale The Scaties ed ligh t diet es en direchion oG midence thaonh the he amsle CoTe mateaial caih cal reate thom amgle Bendius o ss es re6a ctive inden chom ges hen foc is bemt mote culer chon er . TG deniha of chanes c changes .TG the ght ay Taiu indea the avngle OG müdnce the Oat of he will come coill mot ablect omd mateial FO C occass it two osser These Couptng to sses 0ined the total lsht which at no be fs ansteu ed as toss Cansiaes ed