ACTIVE GPS TRACKING
An operational GPS tracking mode, in which the offender is being frequently monitored while moving outdoors. Location points are collected and uploaded in configurable intervals, which mostly varies in accordance with Zone violation.
 
AGPS
Assisted GPS is a mechanism that is aimed to enhance the performance of GPS-based devices by shortening the Time To First Fix (TTFF) in cases of poor a missing satellites reception.
The mechanism is based on predicted satellites route, stored in a designated server, and downloaded to the GPS tracking device.
 
ALCOHOL MONITORING
A sub-program that enables soberness verification of the offender, while is in Home curfew.
The alcohol detection sensor sends the results to the monitoring center and the results are compared to the pre-defined threshold.
Alcohol tests may be performed on demand, in scheduled times or in random manner.
The technology usually incorporates an additional method of verification such as face recognition, fingerprint biometrics etc.
 
DUAL-PIECE GPS DEVICE (AKA TWO-PIECE)
In a Dual-piece platform, the regular transmitter Tag is used, and an additional portable device functions as the Receiver.
The portable device is equipped with GPS and other location based capabilities, in addition to GPRS/3G communication abilities.
A proximity mechanism is usually set in order to alert cases where the offender is distanced from the portable device.
 
ENCRYPTED COMMUNICATION
Either proprietary or standard Public-key infrastructure (PKI), are being used in order to encode the data (or part of it) during a communication made between two or more components.
These may be for example Tag and Receiver, or Receiver and Monitoring center.
Implementing encryption protocols allows increased security communication paths, and reduces the risk of monitoring and fraud attempts by un-authorized factors.

EVENTS AND ALERTS
Describes breach of the surveillance conditions (e.g., Bracelet Tamper) or designated action
(e.g., Left home) that the offender performs, and is being recorded and uploaded to the monitoring system.
In accordance with the handling protocol, some of these events may require intervention while others may be considered as notification only.
 
EXCLUSION ZONE
An area set by the monitoring center that is marked as an area that the offender is
prohibited from entering to.
The exclusion zone may be surrounded with a buffer alert zone.
The shape of the zones varies and may be circular, rectangular or free shape polygon.
 
GLONASS
The Global navigation satellite system is the corresponding Russian satellite system to the American GPS system. The system is fully operational today.
Many of the chipsets vendors offer multi-system support chips that allow both GPS and GLONASS support.
 
GPRS/3G COMMUNICATION
Cellular packet data communication method.
Unlike Circuit Switched Data (CSD) that is being vanished gradually, the use of the packet-based methods allows faster communication, based on IP address, and does not require an analogue modem on the celled side.
 
GPS
Global Positioning System is a satellite based system, developed and deployed by the US government. 24 active satellites are covering earth and provide a location accuracy of approximately few meters, depending on several factors.
One of the main disadvantages of the GPS system is indoor reception.
 
HOME UNIT – READER
A receiver (or transceiver) that has the capability to de-code the Tag´s transmissions and report to the monitoring system information with regards to presence, absence and
violations of the offender.
A home unit may use one or more communication methods, including:
Cellular (GPRS/3G), Land line, Ethernet and wifi.
 
HOUSE ARREST / HOME CURFEW
Usually refers to a confinement at home, that the offender is sentenced to, and that integrates a form of RF tracking or other.
House arrest is set in combination with scheduled timeframes, determining the offender´s permitted absence times, and his curfew times.
 
HYBRID GPS TRACKING
An operational mode where the offender´s tracking points are uploaded in less frequent intervals than in Active mode.
Violations, however, are uploaded immediately.
 
INCLUSION ZONE
An area set by the monitoring center as one that the offender may reside in.
In most GPS tracking programs, the inclusion zone is the offenders´ house and therefore also combines scheduled timeframes.
 
LBS
Location Base Services describes methods other than GPS used for determining the positioning of an object or a person.
In most cases, these methods are based on information retrieved from the cellular network, and usually include triangulation of cell towers, made to increase accuracy.
The LBS is used in cases where GPS coverage is lost, and is considered to be a much less accurate location determination method, but may give a general idea as for the current location.
 
MONITORING CENTER
Refers to a control room, used for supervision and surveillance of the offenders.
It is commonly populated 24 hours a day.
The monitoring agents use internal protocols for handling violations in accordance with the severity, offender profile etc.
The monitoring center is operated by either a team from the Ministry of justice or by a private company, hired for this purpose by the government.

PASSIVE GPS TRACKING An operational mode where the offender´s tracking and events information is being uploaded to the monitoring center only upon return to the home curfew zone.
The communication is usually done by the Home Unit.
This mode is usually used in order to reduce cellular communication costs and/or
for low risk offenders.
It is important to emphasize that the information is collected and recorded in real-time and hence may be used for crime scene investigations.
 
POINT OF INTEREST (POI)
Represents type of locations that may be used in order to determine exclusion or inclusion zones for GPS tracking programs.
An example for such use of POI may be Schools marked as exclusion zones for
high risk offenders.
 
SINGLE-PIECE GPS DEVICE (AKA ONE-PIECE)
A common name for a combined device that incorporates the Tag and the Receiver
into a single platform.
Usually being a device which is larger than a regular Tag, as it includes GPS and GPRS/3G capabilities. A main con is the short battery life, especially when used in Active mode.
 
TAG
A bracelet worn either on the wrist or the ankle, and transmits the offender ID, timestamp and additional information to the receiver unit (Home unit or GPS device).
Transmitting frequency varies between countries, but the ones mainly in use are:
433Mhz, 315Mhz and 418Mhz.
Tag may also come in other shapes when used for tracking assets or vehicles.
 
VOICE VERIFICATION
A biometrics system that compares the offender´s voice, as was taken during the enrollment phase, to a call made either randomly or on demand.
The service adds an indication to confirm the offender´s identity in case of need.
The current Voice Verification systems are based on either pre-defined set of sentences or make use of free-speech engines.