How to simulate the FEC gain TEST in LAB or onsite during ATP
1.OAU-1 should be forced opening by using OPTP common，and it will send the dummy light as noise signal.OPTP common as following:
:optp:bid,1,83,1,17,8,c1,1c,1,0,0,0,C8 ; #force open laser common，C8---〉200----〉20dbm , Bid – board id number(hex)
:optp:bid,1,83,1,13,1,4,0,1 ; #query the laser states common
2.OLP should use the TO1/TO2/TI port as the topology.
3.OSA should monitor the mon port of OAU-2,this OSNR is OTU OSNR tolenrance.
4.FEC/AFEC Gain= OTU OSNR tolenrance（open FEC/AFEC） – OTU OSNR tolenrance
(1) Establish the testing configuration according to the above diagram.
(2) Configure the tester according to the tested service.
(3) Disable FEC function of OTU.
(4) Adjust the optical attenuator 1 to decrease the attenuation gradually, until the tester detects errors of 10E-10.
(5) Wait for 5 minutes and check OSNR.
(6) Enable FEC function of OTU.
(7) Adjust the optical attenuator 1 to decrease the attenuation gradually, until the tester detects errors of 10E-10 again.
(8) Wait for 5 minutes and check OSNR.
(9) Compare the result.
Activity should be done very carefully as the output LASER is high & dangerous for eyes
for more detail please refer the attached