Installation guide

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Wi-Fi Location-Based Services—Design and Deployment Considerations
OL-11612-01
Deployment Best Practices
Tips for Successful Calibrations
Number of Samples
As stated earlier, the calibration application within WCS ensures that a sufficient number of
location-to-access point measurements (no less than 150 per band) are collected before allowing the
calibration user to move forward with calibrating the model and applying it to floors. During the
calibration process, use the blue crosshairs on the calibration grid (shown in Figure 49) as suggestions
on where to position yourself and perform data point collection. Although the coordinates of the blue
crosshairs are merely suggested collection points, they are an excellent way to stay on track and
uniformly cover ground, especially within large environments. Dark squares appear on the calibration
grid showing the suggested locations that were actually visited, with the surrounding area of localization
that is now “covered” being indicated by a blue color for 802.11b/g, yellow for 802.11a, and green for
both bands, as shown in Figure 50.
Figure 50 Example of a Completed 2.4/5 GHz Calibration
Keep in mind that the calibration utility in the current release of the system is not able to recognize
obstructions or hazards in the floorplan overlay such as interior walls, pipes, racks, or other structures.
Therefore, it is not unusual to have a suggested data point crosshair appear in an area that is physically
inaccessible. In that case, every attempt should be made to visit a location as close as possible to the
inaccessible location and perform the calibration data collection there.