Is there a GPS in them? How do they know where you are supposed to be and if you stray from that location? Is there a grace period for you to get back inside that location?
In: Other
Mostly just a base station that communicates via the cellphone network. Older units relied on landlines.
The base station sends a radio beacon to the ankle unit and if the ankle unit doesnt reply, means it has gone out of range and the base station sends an alarm.
The central monitoring computer also sends a beacon via the cellular network to the base station to probe it for various pieces of status information regularly.
The units can be often remotely programmed such as a curfew can be imposed where it wont send an alarm unless the ankle unit is within range at certain times of the day.
Latest Answers