88
2.048Mbps Wireless Modem
SALES: 0118 965 5100
2. For X.21, RS-530 and V.35, verify that:
•
The DCE Internal clock or DCE External clock or DTE setting on each unit is matched by
the DCE/DTE configuration of the end equipment.
•
The clock rate setting of the end equipment matches the clock rate setting of the unit.
3. For E1, T1, Fractional E1, Fractional T1 verify that:
•
The line coding scheme used by the 2.048Mbps Wireless Modem and the end equipment
are the same.
•
For E1 or Fractional E1 verify that the Balanced/Unbalanced configuration of the LIU (set
by the jumpers on the LIU board) matches that of the end equipment.
Problem 5: The radio link is stable, but the error rate on the end equipment is
unacceptable
To check error rate on end equipment:
1. From the Counters and Tracers menu, select
Watch Alarm
s.
2. If the “Modem rate too low for RADIO BUFFER ERROR RATE” alarm appears, this
indicates that the difference between the LIU clock rate and the modem rate is too low to
correct all radio errors.
To solve this problem:
•
Improve the radio link quality (reduce error rate).
•
Decrease the LIU clock rate.
•
Increase the modem rate.
3. If the “Delay setting may be too short to correct all errors” alarm appears, this indicates
that long bursts of errors overcome or nearly overcome the error correction mechanism. To
solve this problem Increase the link delay.
4. If no alarm appears, this indicates that the errors are not a result of errors on the radio link,
but rather a configuration or a physical cable problem with the end equipment. Use the
Loopback mode
in the LIU Parameters menu to locate the source of the problem.
•
For X.21, RS-530 and V.35, verify that the DCE Internal Clock or DCE External Clock or
DTE settings on each unit is matched by the DCE/DTE configuration of the end equipment.
•
For E1, T1, Fractional E1 and Fractional T1, verify that the line coding scheme used by the
2.048Mbps Wireless Modem and the end equipment are the same.
