User's Manual

Modem configuration
Technical User Manual
InfiLINK XG – CLI commands
21
HINT
If Absolute RSSI value goes above -40 dBm, decrease Tx power of the remote unit in
order to keep it within -40..-50 dBm for performance maximization.
Step 4
Optimize link performance
- Adjust Maximal link distance parameter based on the measured
distance.
HINT
Check measured link distance, using xg stat outputs and adjust xg –max-distance
settings by adding 200-300 m to the measured value.
- Check the air block error rate Acc TBER in xg stat outputs and adjust
AMC strategy if necessary. It is recommended to use Normal strategy
initially and then adjust it based on target and actual Acc TBER values.
HINT
Acceptable error rate Acc TBER depends on the application. See examples in Table 1
below.
Application
Acceptable error rate
TCP-based applications (web, FTP, etc.)
10
-4
Voice-over-IP
10
-5
UDP video (CCTV, IPTV, etc)
10
-6
TDM-over-IP
10
-7
..10
-9
Table 1 - Acceptable error rates for different applications
- Select the most appropriate air frame period
HINT
The system supports frame period values ranging from 1 to 10 ms.
Frame with period of 1 ms gives the lowest latency (from 500 us one-way).
Frame with period of 10 ms has lowest overheads. As a result, it has
approximately 12% better maximal throughput for the same MCS than one with
period of 1 ms. Also, 10 ms frame provides more stable performance - it has
significantly lower distance penalty compared to 1 ms: at 100 km the maximal
throughput decreases by 7% at 10 ms and by 75% at 1 ms.