TrimTrac ProE Locator, Техническое руководство

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TrimTrac ProE Locator Technical Manual v2.0e 26
Geofences and GPS Fix Rate
Depending upon how strictly geofences must be enforced, it may be advantageous
to set the GPS Fix Rate to “1=GPS 1Hz”. Geofences are enforced based upon the
most recently computed GPS position. If the TrimTrac ProE only computes a
new fix each time it enters the FIX State, then the latency in reporting a geofence
violation is extended to the time it takes the TrimTrac ProE to cycle through the
entire state machine.
If a more vigilant enforcement of the geofence is desired, then the GPS Fix Rate
can be increased to once per second. This would afford more continuous
enforcement of the geofences, albeit at the expense of power consumption, and
near real time reporting of violations.
Geofences and Automatic Message Log Dump
GSM coverage may or may not be available throughout the geofence area and
beyond. This means that a device may be able to slip out of and then back into a
geofence area undetected by server, at least until GSM coverage became
available. If a geofence violation had occurred while there was no GSM
coverage, the device will keep the Geofence Status flag set as a violation until
reported to the server application whether not the device is inside or outside the
geofence area at the time the message is transmitted.
Before the device is able to transmit a message with the geofence violation, the
TrimTrac ProE may have traveled well beyond the geofence area while outside
GSM coverage. If the Automatic Message Log Dump feature is enabled, then the
device will not only transmit the message noting the geofence violation when
GSM coverage becomes available, but it will also transmit all positions logged
while traveling in violation of the geofence outside GSM coverage. In so doing,
the server application will not only know that a geofence violation had occurred,
but also where the device traveled in the mean time.
Geofences and Scheduled Hours Mode
Geofence enforcement can be linked to time of day enforcement by using the
Scheduled Hours Mode feature described in the next section. A geofence can be
configured to be enforced 24/7 or during normal working or after hours. This
later capability is particularly useful when, for instance, a vehicle is allowed to
roam over a greater area during normal working hours, but needs to be restricted
to a smaller area after hours. Please note that the geofences can be linked to the
Scheduled Hours time periods even if the Scheduled Hours Mode feature itself is
not enabled.
Scheduled Hours Mode
This feature establishes daily consecutive hours during which use of the monitored asset
is considered either “authorized” or “unauthorized” or when geofences are to be
enforced during different times of the day.