AON2200C Outdoor Optical Node
Solutions Provider for FTTx, RFoG, and HFC
www.ascentcomtec.com
Page 12 of 14
Failure Phenomenon
Failure Cause
Solution
After connecting the
network, the image of the
optical contact point has
obvious netlike curve or
large particles highlights but
the image background is
clean.
1. The optical input power of the
optical receiver is too high, make the
output level of the optical receiver
module too high and RF signal index
deteriorate.
2. The RF signal (input the optical
transmitter) index is poor.
1. Check the optical input power and make
appropriate adjustments to make it in the
specified range; or adjust the attenuation of
optical receiver to reduce the output level and
improve index.
2. Check the front-end machine room optical
transmitter RF signal index and make appropriate
adjustments.
After connecting the
network, the image of the
optical contact point has
obvious noises.
1. The optical input power of the
optical receiver is not high enough,
results in the decrease of C/N.
2. The optical fiber connector or
adapter of the optical receiver has
been polluted.
3. The RF input signal level of the
optical transmitter is too low, make
the modulation degree of the laser is
not enough.
4. The C/N index of system link signal
is too low.
1. Check the received optical power of the optical
contact point and make appropriate adjustments
to make it in the specified range.
2. Improve the optical received power of the
optical contact point by cleaning the optical fiber
connector or adapter etc. methods. Specific
operation methods see “Clean and maintenance
method of the optical fiber connector”.
3. Check the RF input signal level of the optical
transmitter and adjust to the required input
range. (When the input channels number less
than 15, should be higher than the nominal
value.)
4. Use a spectrum analyzer to check the system
link C/N and make appropriate adjustments.
Make sure the system link signal C/N
﹥
51dB.
After connecting the
network, the images of
several optical contact
points randomly appear
obvious noises or bright
traces.
The optical contact point has open
circuit signal interference or strong
interference signal intrusion.
1. Check if there is a strong interference signal
source; change the optical contact point location
if possible to avoid the influence of the strong
interference signal source.
2. Check the cable lines of the optical contact
point, if there is shielding net or situation that
the RF connector shielding effect is not good.
3. Tightly closed the equipment enclosure to
ensure the shielding effect; if possible add
shielding cover to the optical contact point and
reliable grounding.
After connecting the
network, the images of
several optical contact
points appear one or two
horizontal bright traces.
Power supply AC ripple interference
because of the bad earth of
equipment or power supply.
Check grounding situation of the equipment,
make sure that every equipment in the line has
been reliably grounding and the grounding
resistance must be <4
Ω.
