Electronic monitoring equipment is used to augment supervision of offenders who require daily monitoring of their activities or are required by law to be monitored by this system. There are four different types: the RF (radio frequency), MEM’s (Mitsubishi Electronic Monitoring) VB (Visual Breathalyzer), MEMS VBR (Visual Breathalyzer with Radio Frequency) and the GPS (Global Positioning System.
The RF unit consists of an ankle bracelet transmitter and a receiver that attaches to the offender’s home telephone service. The system provides the supervising agent a daily report of the offender’s arrival and departure at their authorized residence as well as any curfew non-compliance.
Speaker ID uses the offender’s home phone system and has no attachments. During initialization the offender calls from the supervising agent’s office and answers a series of questions. The computer then records their voice and the system randomly places phone calls to the offender’s home and measures curfew non-compliance.
The GPS unit contains an ankle bracelet transmitter, MTD (miniature tracking device), and a charging station that connects into the offender’s home telephone system or is functional without a land line. The GPS system uses 24 satellites provided by the Department of Defense and the MTD transmits a signal to three of these satellites, which allows the supervising agent to monitor the offender’s activities and movements 24 hours a day through a secured internet site.