Wilan LIBRA 5800 AP, Руководство пользователя

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Appendix D: Linktest and Link Statistics
120 Libra 5800 Series User Guide
The transmitting (local) unit generates pseudo-random packets of data that it sends to the receiving (remote)
unit at the other end of the link. The remote unit compares the packets and measures the BER (bit error rate),
RSSI, Fade Margin, Forward Error Correction (FEC) and other statistics. It sends those statistics and the
original data back to the local unit. The local unit reads the data and displays the accumulated statistics.
Linktest can run from the base to any remote in a system, or from a remote to the base, but it cannot run from
one remote to another.
Linktest variables
You can set four variables when starting Linktest. They are station ID of the remote, accuracy of the test,
symbol variation and transmission speed.
You must set the Radio Station ID.
The system uses default values
for the others if you do not set them.
Before you start a Linktest, you must set the remote unit’s ID. See Setting the RF Station ID (P-MP Only) , page
70 for information about viewing and setting station IDs.
Note:
Linktest will produce invalid results if run at the same time from both ends of the same link.
➧
To run Linktest
1. Connect a PC, Laptop or PDA with terminal emulation software to the serial port of the unit from which
you will run Linktest. This can also be done via Telnet and TCP/IP.
2. Press the Esc key until you enter command line mode, as indicated by the
wilan>
prompt.
3. Type the following command line after the
wilan>
prompt.
Linktest <station id of remote> [<acc> <var> <pps>]
where
TIP:
Linktest can run while the system carries user data, but the test overhead reduces the links data capac-
ity. It is better to run Linktest while the system is
idle.
<station ID of
remote>
RF Station ID number of Linktest remote unit. This number is the Access
Point of the system if Linktest is run from a CPE.
<acc>
Accuracy of the test, expressed as 1E<acc> bits. The default accuracy is 6
(1E6) or one million. The <acc> value defines the number of bits sent for
each line of displayed statistics. Sending more bits produces more accurate
statistics, but increases the time needed to run the test. The test sends 10
times as many bits as the acc value. Choosing an acc of 6, or 1 million,
causes the test to send 1E7 bits, or 10 million.