Optical Power Debugging in the DWDM System Reference Points in the DWDM System So So OAC So So OTS Si So OTS Si Si OMS OCH Si Si OAC Content    Purpose of Optical Power Debugging Basic Formulas Optical Power Calculation Optical Power Debugging Purpose We have Purposes: Make each channel has the same the optical power in the transmission Make the OA working in the Best State Make the OTUR working in the Best State Optical Power Debugging Purpose Make each channel has the same the optical power in the transmission  In the transmission, the output power from OA cannot be as high as we want, so the limited optical power should be allotted to each channel equally After demultiplexing, each receiver can get the same optical power Optical Power Debugging Purpose Continue: If In the receiving end: O D U Over loading OTUR Client Side OTUR Under sensitivity Control the difference between any two waves to less than 3dB The less difference the better Fl atn e ss Optical Power Debugging Purpose Make the OA working in the Best State OA has three working state: Over-Saturated State; Saturated State; This is the best working state Under-Saturated State; Optical Power Debugging Purpose Make the OTUR working in the Best State 10G PIN APD 0~-14dBm Best: -6dBm -9~-21dBm Best: -12dBm Optical Power Debugging Purpose  OTUT Output Power:  10G  OTUT or OTUG (EA or LD)=-1~ -5dBm Content    Purpose of Optical Power Debugging Basic Formulas （（（（ Optical Power Calculation Basic Optical Power Calculation PIN -0.5dBm ch1 TS2C TS2C LT LT λ5 2220 2520 BA PA λ1 ODU40 ch5 ┇ OMU40 Input TS2C TS2C LT LT λ1 TS2C TS2C LR LR ch1 Output ┇ λ5 TS2C TS2C LR LR ch5 Line loss = 20dB Insertion loss = 7dB Insertion loss = 7dB Before OMU: Optical power for each channel is the same Before OA: OA works in the best state Before TS2C LR: Receiver works in the best state Basic Optical Power Calculation PIN -0.5dBm ch1 ┇ TS2C TS2C LT LT λ5 2220 2520 BA PA Line loss = 20dB IL = 7dB Pin Pout P40out=P1out+10lg40 P1out=P40out-10lg40 =20-16 =4(dBm) λ1 ODU40 ch5 λ1 OMU40 Input TS2C TS2C LT LT TS2C TS2C LR LR ┇ λ5 IL = 7dB TS2C TS2C LR LR ch1 Output ch5 Basic Optical Power Calculation PIN -0.5dBm ch1 TS2C TS2C LT LT λ5 2220 2520 BA PA IL = 7dB Line loss = 20dB λ1 ODU40 ch5 ┇ OMU40 Input TS2C TS2C LT LT λ1 ┇ λ5 IL = 7dB PoutOMU PInOBA Attenuation=P1outOMU-P1inOBA =(-0.5-7)-(4-22) =10.5(dB) nearly 10dB Before OBA: TS2C TS2C LR LR 10dB attenuation TS2C TS2C LR LR ch1 Output ch5 Basic Optical Power Calculation PIN -0.5dBm ch1 ┇ TS2C TS2C LT LT λ5 2220 2520 BA PA IL = 7dB Line loss = 20dB PoutOBA PAfter Line=P1outOBA-Line Loss =4-20 =-16(dBm) PAfter Line λ1 ODU40 ch5 λ1 OMU40 Input TS2C TS2C LT LT TS2C TS2C LR LR ┇ λ5 IL = 7dB TS2C TS2C LR LR ch1 Output ch5 Basic Optical Power Calculation PIN -0.5dBm ch1 ┇ TS2C TS2C LT LT λ5 2220 2520 BA PA IL = 7dB Line loss = 20dB Pin P40out=P1out+10lg40 P1out=P40out-10lg40 =20-16 =4(dBm) λ1 ODU40 ch5 λ1 OMU40 Input TS2C TS2C LT LT ┇ λ5 IL = 7dB Pout TS2C TS2C LR LR TS2C TS2C LR LR ch1 Output ch5 Basic Optical Power Calculation APD -0.5dBm ch1 TS2C TS2C LT LT λ5 2220 2520 BA PA IL = 7dB Line loss = 20dB λ1 ODU40 ch5 ┇ OMU40 Input TS2C TS2C LT LT λ1 Attenuation=PAfter Line-P1inOPA =-16-(4-25) =5(dB) Before OPA: ┇ λ5 IL = 7dB PAfter Line PInOPA 5dB attenuation TS2C TS2C LR LR TS2C TS2C LR LR ch1 Output ch5 Basic Optical Power Calculation PIN -0.5dBm ch1 TS2C TS2C LT LT λn5 2220 2520 BA PA IL = 7dB Line loss = 20dB λ1 ODU40 ch5 ┇ OMU40 Input TS2C TS2C LT LT λ1 Attenuation=P1outOPA-P1inODU =4-7 =-3(dB) Before ODU: 3dB attenuation 备备备 saturated output 备备备备 ┇ λ5 IL = 7dB PoutOPA PinODU TS2C TS2C LR LR TS2C TS2C LR LR ch1 Output ch5 Question?  Just now, we use one channel optical power in the attenuation calculation What happened if we use channels or 40 channels optical power in the calculation? Basic Optical Power Calculation Basic Optical Power Calculation Basic Optical Power Calculation   CARD TYPE SLOT PORT IN - PORT OUT Attenuator   Insertion Loss Channel Gain Poutch (IL) (G) (1 Channel) dB dB dBm TS2C 0-1-13/0-1-14/ 0-2-13/0-2-14     - - -0.50 OMU40 0-1-6 CHxx - OUT   7.00 - -7.50 SOP1 0-1-15 Tin - Tout1/Tout2   3.00 - -10.50 SEOBA2220 0-1-20/0-2-20 IN - OUT - 21.50 4.00 Basic Optical Power Calculation A: B: Basic Optical Power Calculation C: Basic Optical Power Calculation ... Points in the DWDM System So So OAC So So OTS Si So OTS Si Si OMS OCH Si Si OAC Content    Purpose of Optical Power Debugging Basic Formulas Optical Power Calculation Optical Power Debugging Purpose... one channel optical power in the attenuation calculation What happened if we use channels or 40 channels optical power in the calculation? Basic Optical Power Calculation Basic Optical Power Calculation... Under-Saturated State; Optical Power Debugging Purpose Make the OTUR working in the Best State 10G PIN APD 0~-14dBm Best: -6dBm -9~-21dBm Best: -12dBm Optical Power Debugging Purpose  OTUT Output Power: 