Cambium Networks PMP 450 AP, Configuration Manual

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Chapter 3: Operation System information
Page
3-16
Cyclic Prefix OFDM technology uses a cyclic prefix, where a portion of the end of a
symbol (slot) is repeated at the beginning of the symbol to allow multi-
pathing to settle before receiving the desired data. A 1/16 cyclic prefix
means that for every 16 bits of throughput data transmitted, an additional bit
is used.
Air Delay This field displays the distance in feet between this SM and the AP. To derive
the distance in meters, multiply the value of this parameter by 0.3048.
Distances reported as less than 200 feet (61 meters) are unreliable.
Receive Power This field lists the current combined receive power level, in dBm.
Signal Strength Ratio This field displays the difference of the Vertical path received signal power
to the Horizontal path received signal power.
Signal to Noise Ratio This field lists the current signal-to-noise level, an indication of the
separation of the received power level vs. noise floor.
Beacons Displays a count of beacons received by the SM in percentage. This value
must be typically between 99-100%. If lower than 99%, it indicates a
problematic link. This statistic is updated every 16 seconds.
Transmit Power This field lists the current combined transmit power level, in dBm.
Note
The red SM message “target power exceeded maximum”
does not necessarily indicate a problem.
In this case, the AP is requesting the SM to transmit at a
higher power level, but the SM is restricted due to EIRP limits
or hardware capabilities. This message can be an indication
that the SM is deployed further from the AP than optimal,
causing the AP to adjust the SM to maximum transmit power.
Data Slots Down This field lists the number of slots used for downlink data transmission.
Data Slots Up This field lists the number of slots used for uplink data transmission.
Contention Slots This field indicates the number of (reserved) Contention Slots configured by
the operator. See
Contention slots on page 1-209 .
Site Name This field indicates the name of the physical module. You can assign or
change this name in the SNMP tab of the SM Configuration page. This
information is also set into the
sysName SNMP MIB-II object and can be
polled by an SNMP management server.
Site Contact This field indicates contact information for the physical module. You can
provide or change this information in the SNMP tab of the SM Configuration
page. This information is also set into the
sysName SNMP MIB-II object and
can be polled by an SNMP management server.