SAF FreeMile Series, Руководство пользователя

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The SAF FreeMile Series Full Outdoor Unit Technical Description and Configuration Guide • Rev. 1.3
© SAF Tehnika JSC 2012
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This example demonstrates how the new technology, based on an ACM mechanism, can play a
key role in the development of cost ‐ effective next ‐ generation wireless access networks, by taking
advantage of traffic evolution from synchronous TDM traffic to packet IP ‐ based traffic.
The Weak FEC option allows increasing overall capacity of the link in terms of deteriorating RSL
sensitivity threshold. Note, that using 32QAM with total capacity of 100Mbps, SAF FreeMile
automatically uses Strong FEC mode with better sensitivity, but incrementally enabling E1 channels,
SAF FreeMile adapts it's forward error correction, till the maximum 104Mbps capacity (100Mbps
Ethernet + 2E1) is enabled and SAF FreeMile operates in Weak FEC mode.
4.1.3 Loopback configuration
Loopback tests are accessible using local or remote management methods.
For safety purposes all loopbacks (local and remote) can be set on a fixed time interval only. If no
time interval is specified, the default value is 60 seconds (1 minute).
Figure 4.5. Loopback modes

E1 loopback mode loops signal back to local end in bounds of E1 interface. E1 FAR loopback
loops signal back to remote end and allows testing performance over the link. E1 loopback
mode must be set on the particular channel you are wishing to test. If no E1 channels are
selected, E1 loopback mode is not available;

MODEM loopback mode loops signal back to local end after the modem;

RF loopback mode loops signal back to local end by linking radio frequencies.
Figure 4.6. Loopback configuration
1. Loopback name – allows choosing loopback mode
2. Loopback time duration ‐ loopback activity time in seconds (command line –
loopback {status|none|rf|modem|e1 <num> [far]} [<time>] ).
3. Tx mute – allows turning transmitter power off for specified time. It may be
effective when diagnosing on interference existence – when transmitter power of
one side is off, you should not experience significant RSL on the other side
(command line ‐ radio txmute [on|off] [time] );
4. By pressing “Apply” changes made to corresponding section apply only for the local
side of SAF FreeMile.
5. Pressing „Save” button saves current configuration only in local unit;
6. Pressing „Save in local and remote” button saves current configuration in both local
and remote units;
7. System returned ‐ in case of error or incorrectly entered parameter value, or other
problems in the whole page – info message will be displayed here. Otherwise it says
“Ok”.