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Nortel WLAN Location Engine 2340 Web GUI
NN47250-504 (324122-A Version 01.01)
Fine-Tuning the Tracking Engine
Running the Evaluator and fixing the flagged problems (as described in Section 0) eliminates many potential problems
with device tracking. Some problems cannot be detected without physically walking through the space under surveil-
lance. As you move through locales during the testing phase, the Nortel WLAN Location Engine Tracking Engine can
recognize the locale and RF Fingerprint you are in within 60 to 90 seconds of your arrival. If it takes longer (i.e. unac-
ceptable latency), or if the wrong RF Fingerprint and locale are reported, the first approach can always be to recalibrate,
capturing new RF data for the problem RF fingerprints. This will correct problems with the original calibration data
created by transient RF anomalies, network outages, or human error.
If recalibration does not correct the problem, then consult the appropriate section of this chapter to address the problems:
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Adjacent locale misreported.
•
Wrong side of border reported.
•
Distant locale misreported (because of RF resemblance to actual locale).
Adjacent Locale misreported
If the Nortel WLAN Location Engine Tracking Engine incorrectly reports your position as being in an adjacent locale,
your first approach can be to make sure that there are RF fingerprints on either side of the transition point between the
two locales.
Wrong side of border reported
If you are standing near the edge of a locale, and the Nortel WLAN Location Engine Tracking Engine can't determine
whether you are just inside or just outside the locale, the position reported by the Tracking Engine bounces back and
forth between the locale in which you are physically standing and the adjacent locale. To correct this problem, try adding
or recalibrating RF Fingerprints. In addition, it may be helpful to add a Location AP and then recalibrate.
Distant Locale misreported
On occasion, unusual RF dynamics in a building artificially make two locales appear identical, even though they are
physically distant from one another. For example, any time a device enters a locale named ‘Conference Room A’, its
locale is always misreported as ‘Lunch Room,’ even though Conference Room A and the Lunch Room are on different
floors.
You can add two Location APs as follows:
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One in the correct locale
•
Another in the misreported locale.
