Burst Error Rate (BER)
Burst error rate, BER, is cumulative ratio of burst errors to total number of received bursts in percentage format.
BER Includes:
- Uncorrectable FEC
Uncorrectable FEC (forward error correction) is a condition where valid burst was received and demodulated; however, there were more errors in the burst than could be corrected by the FEC.
High number of uncorrectable FEC caused by:
o low SNR (link is too long),
o multipath fading
o Interference
- No Unique Word
No Unique Word Count indicates that some energy was detected (above the minimum power threshold) during a scheduled time slot, however no Unique Word was detected.
The Unique Word is an identifier that is part of the preamble of every wireless burst and must be valid in order for a burst to be properly demodulated.
No UW on the BSU caused by interference or collisions during contention requests
No UW on the SU caused by Interference or radio too close to base (signal should be less than –45dBm)
- No Energy errors
No energy error is when scheduled packet did not arrive, or arrived with very low power level (below the minimum energy level threshold).
On the BSU: error count increases for each frame that does not have contention traffic. This is a normal condition.
On the SU: Numerous NO ENERGY errors usually indicate a VERY low signal level. SU should be pointed again
BSU in a good condition have an errors < 1-2%. BSU with errors < 5 % is still accepted.
High rate BER indicates interference.
What should we do if we found that BER counter more than 5%?
- Reset the BSU radio status counter.
- Step up the Rx power of the BSU (up to -60 dBm).
- Scan the frequency using the FSA tools that belong to the BSU.
- Switch the frequency.
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can u please give me more solutions for decresing Burst Error Rate. because we found one of our BSU had more than 25% BER & we unable resolve the problem. please help us for resolve the issue.
thanks & regards,
santanu
Dear Santanu,
Normally, if there is an interference that impact to your BSU sector, you can check @ the BSU RF Signal Quality. Click the reset signal quality counters button. After resetting the counter, check the ‘No Unique Word Count’ value. If the value is higher than ‘80′, it mean that there is an signal interference.
Have you increase the port receive power of the BSU step by step until reach -60 dBm?
If that way doesn’t solve the problem, maybe you need to change your WSS frequency.
Regards,
TB
In this case, you can check RF pigtail cable of BSU connected from ODU to antenna. In case either it is loose,faulty or having rusted elements on its connector, you might face the issue of burst error because in this case there would be delay in your proper transmission.