A GPS tracking unit, geotracking unit, satellite tracking unit, or simply tracker is a navigation device normally on a vehicle,

asset In financial accountancy, financial accounting, an asset is any resource owned or controlled by a business or an economic entity. It is anything (tangible or intangible) that can be used to produce positive economic value. Assets represent value ...

, person or

animal Animals are multicellular, eukaryotic organisms in the Kingdom (biology), biological kingdom Animalia. With few exceptions, animals Heterotroph, consume organic material, Cellular respiration#Aerobic respiration, breathe oxygen, are Motilit ...

that uses

satellite navigation A satellite navigation or satnav system is a system that uses satellites to provide autonomous geo-spatial positioning. It allows satellite navigation devices to determine their location (longitude, latitude, and altitude/elevation) to high pr ...

to determine its movement and determine its WGS84 UTM geographic position (

geotracking Geopositioning, also known as geotracking, geolocalization, geolocating, geolocation, or geoposition fixing, is the process of determining or estimating the geographic position of an object. Geopositioning yields a set of geographic coordinates ...

) to determine its location. Satellite tracking devices send special satellite signals that are processed by a receiver. Locations are stored in the tracking unit or transmitted to an Internet-connected device using the

cellular network A cellular network or mobile network is a communication network where the link to and from end nodes is wireless. The network is distributed over land areas called "cells", each served by at least one fixed-location transceiver (typically thre ...

( GSM/

GPRS General Packet Radio Service (GPRS) is a packet oriented mobile data standard on the 2G and 3G cellular communication network's global system for mobile communications (GSM). GPRS was established by European Telecommunications Standards Insti ...

/ CDMA/

LTE LTE may refer to: Science and technology * LTE (telecommunication) (Long-Term Evolution), a telephone and mobile broadband standard ** LTE Advanced, an enhancement *** LTE Advanced Pro * Compaq LTE, a line of laptop computers produced by Compaq * ...

SMS Short Message/Messaging Service, commonly abbreviated as SMS, is a text messaging service component of most telephone, Internet and mobile device systems. It uses standardized communication protocols that let mobile devices exchange short text ...

), radio, or satellite modem embedded in the unit or WiFi work worldwide. GPS antenna size limits tracker size, often smaller than a half-dollar (diameter 30.61 mm). In 2020 tracking is a $2 billion business plus military-in the gulf war 10% or more targets used trackers. Virtually every cellphone tracks its movements. Tracks can be map displayed in real time, using GPS tracking software and devices with GPS capability.

Architecture

A GPS "track me" essentially contains a GPS module that receives the GPS signal and calculates the coordinates. For data loggers, it contains large memory to store the coordinates. Data pushers additionally contain a GSM/

/ CDMA/

modem to transmit this information to a central computer either via

in form of IP packets. Satellite-based GPS tracking units will operate anywhere on the globe using satellite technology such as GlobalStar or Iridium. They do not require a cellular connection.

Types

There are three types of GPS trackers, though most GPS-equipped phones can work in any of these modes depending on the mobile applications installed:

Data loggers

GPS loggers

log Log most often refers to: * Trunk (botany), the stem and main wooden axis of a tree, called logs when cut ** Logging, cutting down trees for logs ** Firewood, logs used for fuel ** Lumber or timber, converted from wood logs * Logarithm, in mathe ...

the position of the device at regular intervals in its internal memory. GPS loggers may have either a memory card slot, or internal flash memory card and a USB port. Some act as a USB flash drive, which allows downloading the track log data for further computer analysis. The track list or

point of interest A point of interest (POI) is a specific point location that someone may find useful or interesting. An example is a point on the Earth representing the location of the Eiffel Tower, or a point on Mars representing the location of its highest m ...

list may be in GPX, KML, NMEA or other format. Most digital cameras save the time a photo was taken. Provided the camera clock is reasonably accurate or used GPS as its time source, this time can be correlated with GPS log data, to provide an accurate location. This can be added to the Exif metadata in the picture file. Cameras with a GPS receiver built in can directly produce such a geotagged photograph. In some

private investigation A private investigator (often abbreviated to PI and informally called a private eye), a private detective, or inquiry agent is a person who can be hired by individuals or groups to undertake investigatory law services. Private investigators of ...

cases, data loggers are used to keep track of a target vehicle. The private investigator need not follow the target too closely, and always has a backup source of data.

Data pushers

A data pusher is the most common type of GPS tracking unit, used for asset tracking,

personal tracking Personal may refer to: Aspects of persons' respective individualities * Privacy * Personality * Personal, personal advertisement, variety of classified advertisement used to find romance or friendship Companies * Personal, Inc., a Washington, ...

and

vehicle tracking A vehicle tracking system combines the use of automatic vehicle location in individual vehicles with software that collects these fleet data for a comprehensive picture of vehicle locations. Modern vehicle tracking systems commonly use GPS or G ...

systems. Virtually every cell phone is in this mode per user agreement, even if shut off or disabled storing the data for future transmission. Also known as a "GPS beacon", this kind of device

push Push may refer to: Music * Mike Dierickx (born 1973), a Belgian producer also known as Push Albums * ''Push'' (Bros album), 1988 * ''Push'' (Gruntruck album), 1992 * ''Push'' (Jacky Terrasson album), 2010 Songs * "Push" (Enrique Iglesias s ...

(i.e. "sends"), at regular intervals, the position of the device as well as other information like speed or altitude to a determined

server Server may refer to: Computing *Server (computing), a computer program or a device that provides functionality for other programs or devices, called clients Role * Waiting staff, those who work at a restaurant or a bar attending customers and su ...

, that can store and analyze the data instantly. A GPS navigation device and a mobile phone sit side-by-side in the same box, powered by the same battery. At regular intervals, the phone sends a text message via SMS or GPRS, containing the data from the GPS receiver. Newer GPS-integrated smartphones running GPS tracking software can turn the phone into a data pusher (or logger) device. As of 2009,

open source Open source is source code that is made freely available for possible modification and redistribution. Products include permission to use the source code, design documents, or content of the product. The open-source model is a decentralized sof ...

and

proprietary {{Short pages monitor