Cambium Networks PTP 450 Series, Руководство по настройке

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Chapter 2: Tools Using BER Results tool
Page
2-370
Using BER Results tool
Radio BER data represents bit errors at the RF link level. Due to CRC checks on fragments and packets
and ARQ (Automatic Repeat Request), the BER of customer data is essentially zero. Radio BER gives
one indication of link quality. Other important indications to consider includes the received power level,
signal to noise ratio and link tests.
BER is only instrumented on the downlink and is displayed on the BER Results tab of the Tools page in
any SM. Each time the tab is clicked, the current results are read and counters are reset to zero.
The BER Results tab can be helpful in troubleshooting poor link performance.
The link is acceptable if the value of this field is less than 10
−4
. If the BER is greater than 10
−4
, re-evaluate
the installation of both modules in the link.
The BER test signal is broadcast by the AP/BHM (and compared to the expected test signal by the
SM/BHS) only when capacity in the sector allows it. This signal is the lowest priority for AP/BHM
transmissions.
Figure 80 BER Results tab of the SM