FSL III

In FTTB up to the subscribers building or appartment the medium used is OF and after that connections to the subscriber will be given through existing copper cable or Cat5 cable.In FTTC up to the curb the transmission medium used is fiber and after that the connections to individual susbcribers will be given through copper cable.

Advantages  of Implementing FTT-x Technology

1. People can enjoy enormous amount of bandwidth.
2. In the operator side also if people are enjoying variety of services means the bandwidth will be increased there by the ARPU(Average Revenue Per User) is increased .
3. Operators can provide its subscribers the new technologies thus they can compete with their competitors.
4. Enormous amount of bandwidth is available so it can be upgraded to incorporate future technologies.

FSL- II

FSL can be implemented in three ways.Fiber from the operator end to the subscribers home  FTTH(Fiber To The Home),Fiber from the operator end to subscribers building in which many subscribers are residing FTTB(Fiber To The Building).Fiber to operator end to a nearby place in which subscriber is residing FTTC(Fiber To The Curb).These are generally termed as FTT-X where x denotes the termination point.

FSL-Fiber in the Subscriber Loop-I

All the telephone exchanges,local exchanges will be connected or interconnected through optical fiber .Thus it enables to enjoy enormous amount of  bandwidth to the suscriber.But there is a limitation.ie  from the exchange to the subscribers home we are connecting with ordinary copper cable,which will have limited bandwidth.If we use ADSL2+ technology we could achieve a bandwidth of  24 Mbps for a distance of 5 km.or less.But if we use VDSL techonology the bandwidth we can achieve is about 52 Mbps.but the distance is limited to 1 Km.So all the subscribers should reside within the 1 km radius,which is not possible.Also at each and every 1Km we should place exchanges,which is also not possible.So we will lay optical cable from the exchange to the subscribers home or a very near point.This is called Fiber in Subscriber Loop.FSL.

Blue Tooth

This is a wireless technology for exchanging data using short length radio waves.Invented by Erisscon.We can create personal network also using Bluetooth.Blutooth uses a radio technology called frequency hopping spread spectrum.The band used is 2.4 Ghz  short range frequney band which is globally unlicenced.In basic bluetooth the modulation used is GPSK.As this use radio broadcast communication system,they donot have to be in line of sight.

Optical Fiber Cable types

Pigtail/Patch Cord: These cables are tight buffered cables used for indoor purposes.There will be only one fiber in a single cable.The fiber will be coated with kevlar/aramid material..These are sometimes used for desktop connectivity also.

Loose tube Fibers: These are mainly used for outdoor purposes and contains large number of buffer tubes and inside the buffer tubes large number of fibers depending upon the number of fibers.These fibers will be mostly filled with  jelly to prevent harm to the fibers from water.

Armoured cable: These cables are extensevely used in places where rodents is a problem.There will be metal armouring to prevent rodent penetering. Since there is a  metal part  these should be earthed properly.

xDSL Tester

   xDSL line tester is used for testing the line conditions of various lines like ADSL,ADSL2,ADSL2+.This tester evaluates the line quality,Aprrox SNR,Attenuation,BER etc.There are two types of measurements ,the first one is automatic and second one is manual.In automatic measurement it will give the aprrox value of snr and from that we can conclude whether the line is suitable for providing ADSL connections.By the manual testing we can find the exact attenuation,bandwidth configuration.etc. There is an LED indicator in the meter .At first it will blinks and will be steady afterwareds.Itwill shows whether theDSL line  is enabled.The meter runs on battery.
   The other tests include upstream and downstream statistics,noise margin etc.Various tests can be performed for other layers like ATM Layer,PPP Layer,IP Layer can also be done using the meter.The main benift is that the meter can be configured as a pc as well as a modem.And with out the help of a pc we can test the line parameters .Also from the Pillar/DP we can connect to this meter,.There is a Port called CPE Jack .In that we can connect the ADSL Line .

Parallel and serial Transmission

Consider a case where  8 bits are to be transferred from sender end to receiver