OTDR

PowerPoint Presentation

Transmission Training 2015Technology(SDH, DWDM)Bandwidth (STM64, STM16, STM4, STM1)Cable(Core and Access Network)Save cost (Correct length replace of cable)OTDR(Measure Machine)Contains.How many reason to make down one link?How many reason to make down one BTS? Transmission Training 2015Transmission Training 2015Technology:In Movitel were using 2 type of technology : SDH, DWDM

PDHSDHDWDMInside of SDH, using more for monitor VIBASynchronous DigitalSynchronous Digital One fiber, one signal One fiber many signalElectrical MultiplexOptical MultiplexSupport until 10GCan support 900GSDH technology

Transmission Training 2015

DWDM technology

Transmission Training 2015

Transmission Training 2015BandwidthActually we have 4 bandwidth:STM64= 10 Gbits => 4*STM16STM16= 2.5Gbits => 16*STM1STM4= 622 Mbits => 4*STM1STM1= 155 MbitsTransmission Training 2015Cable Movitel:How Many type of cable we have generally?What type of cable we can use for Core Network, access networkHow many km of cable we fix?

Different type of cable for core and access network

Cable ReferenceG.6526G655WAVELENGH1310 15501310 1550DispersionBig dispersionSmall dispersion Transmission Training 2015 Transmission Training 2015Whats Cable 6G655 ?

Transmission Training 20156G655 This is cable for Backbone. ADSS 24Fiber(6G655) have 6 fibbers type "G655" must use for backbone 1A, 1B and 1C HANG cable. 6 G655 Fibers start from 19 to 24. - 18 G652 Fibers start from number 1 to number 18.Especial, G655 fibers need use for DWDM links. it have dispersion small per 1km. used more for connect DWDM, Backbone; Type of Fiber:

Transmission Training 2015MMF(MuItimode Fiber): Generally we use this for short distance, and have low rate;Ex: inside of bts, machine roon;

SMF(Single Mode Fiber): Generally this fiber we use for long distance;Transmission Training 2015Save Cost Transmission: Change wrong length of cableSave Cost Estimated Transmission - MovitelActivityDescriptionTotal Number Incident monthlyNumber incident Actually cost number incidentSuperviseCost After reducedEstimate costChange wrong length of cableFind broken point exatly; Replace necessary cable 6565 ( Replaced cable 300 m average)16.575 $Trans. Dept.(Train for staff); NOC: supervise quantity;60%9.945Patch cord

Transmission Training 2015

Transmission Training 2015OTDR (Optical Time Domain Reflectometer)

Set distance range parameter 50 km

Transmission Training 2015ParameterThe first test (to determine the loss point of cable more clearly):

Wavelength: 1550 nmDistance Range : 50 kmPulse Width: 500 ns Avg Method: Hi SpeedAvg Duration: 1 minThe second test: (to determine the end of cable more clearly)

Wavelength: 1550 nmDistance Range : 50 kmPulse Width: 1 s Avg Method: Hi SpeedAvg Duration: 1 minTransmission Training 2015Attenuation (also called fiber loss)Expressed in dB or dB/km, this represents the loss, or rate of loss between two events along a fiber span

Transmission Training 2015Event loss Difference in optical power level before and after an event, expressed in dB

Fusion Splice or MacrobendConnector orMechanical Splice

Transmission Training 2015How to interpret an OTDR Trace

Transmission Training 2015Connector the pulse go up and down then go straight. It could be due to connector, patch cord.Connector orMechanical SpliceConnectorA connector mechanically mates 2 fibers together and creates a reflective event

Transmission Training 2015Fusion Splices the pulse go down then go straight, it could be due to splice or bend loss point.Connector orMechanical SpliceFusion

A Gainer is a splice gain that appears when two fibers of different backscatter coefficients are spliced together (the higher coefficient being downstream)

End or Break

Transmission Training 2015A Fiber End or Break occurs when the fiber terminates. The end reflection depends on the fiber end cleavage and its environment.

Muito Obrigado!