Users Guide

Dell PowerConnect W-AirWave 7.4 | User Guide Using VisualRF | 265
To tune the frequency for calculating device locations within the VisualRF UI, navigate to the Location
Calculation Timer Settings section as described in Table 142:
All of the other device types (phone, printer, scale, and so on) use the same methodology as detailed above.
To edit the wall settings and select a color for wall types within the VisualRF UI, navigate to the Wall
Attenuation Settings section and select the pencil icon next to each of these settings as described in Table 142:
VisualRF Resource Utilization
When tuning the VisualRF server, use the default settings as recommended. If you do change any of these
settings above, change one at a time and see how the system performs. Each time you restart VisualRF, it will take
at least 30 minutes to return to normal processing.
If you use the 'top' command to check on VisualRF resource utilization, ensure you use the '1' and 'H' flags to
show cores and threads. Remember 'top' also takes 1-2 minutes to normalize and provide accurate data.
Table 141 Location Calculation Timer Settings Section of VisualRF > Setup
Setting Default Description
Legacy Laptop Min/Max
(sec)
90/360 This timer determines how often to calculate location for legacy laptop devices. Taken
with the data samples the calculation would follow:
After minimum timer (90 seconds) check to see if the number of data samples received
from all APs that hear this client are greater than or equal to the number of samples
setting for legacy laptop devices (default of 3 data samples).
If so (Yes to question above) then recalculate the client device's location based on the
samples received.
If not (No to the question above) then wait until the number of sample setting is met and
recalculate. If the number of samples is never met, wait until the maximum timer (360
seconds) and recalculate.
Legacy Laptop Number
of Samples
3 See definition above.
Table 142 Wall Attenuation Settings in VisualRF > Setup
Setting Default Description
Glass Attenuation (dB) 2 Specifies the attenuation for any glass walls that are drawn in VisualRF.
NOTE: All of these values are global variables that cannot be overridden for
individual floor plans. VisualRF uses these values to calculate path loss and client
locations. Walls within VisualRF are interpreted as pure dB loss without adjusting
for wall thickness.
Cubicle Attenuation (dB) 4 Specifies the attenuation for any cubicle walls drawn in VisualRF.
Drywall Attenuation (dB) 6 Specifies the attenuation for any drywall walls drawn in VisualRF.
Concrete Attenuation (dB) 15 Specifies the attenuation for any concrete walls drawn in VisualRF.
NOTE: It is normal for VisualRF to consume 20% of each core with a combination of threads. It will utilize excess CPU cycles on all
cores when required.