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

asset In 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 of ownership that can ...

, 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 The geographic coordinate system (GCS) is a spherical or ellipsoidal coordinate system for measuring and communicating positions directly on the Earth as latitude and longitude. It is the simplest, oldest and most widely used of the various ...

( geotracking) 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 The Internet (or internet) is the global system of interconnected computer networks that uses the Internet protocol suite (TCP/IP) to communicate between networks and devices. It is a '' network of networks'' that consists of private, pub ...

-connected device using the cellular network (

GSM The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation ( 2G) digital cellular networks used by mobile devices such ...

/ GPRS/

CDMA Code-division multiple access (CDMA) is a channel access method used by various radio communication technologies. CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communicatio ...

/ LTE or

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 Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a transmi ...

, or

satellite modem A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay. A satellite modem's main function is to transform an input bitstream to a radio signal and vice versa. There are some devices t ...

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 GPS signals are broadcast by Global Positioning System satellites to enable satellite navigation. Receivers on or near the Earth's surface can determine location, time, and velocity using this information. The GPS satellite constellation is ope ...

and calculates the coordinates. For data loggers, it contains large memory to store the coordinates. Data pushers additionally contain a

/ GPRS/

/ LTE modem to transmit this information to a central computer either via

or GPRS in form of IP packets. Satellite-based GPS tracking units will operate anywhere on the globe using satellite technology such as

GlobalStar Globalstar, Inc. is an American satellite communications company that operates a low Earth orbit (LEO) satellite constellation for satellite phone and low-speed data communications. The Globalstar second-generation constellation consists of 24 lo ...

Iridium Iridium is a chemical element with the symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, it is considered the second-densest naturally occurring metal (after osmium) with a density of ...

. 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 application A mobile application or app is a computer program or software application designed to run on a mobile device such as a phone, tablet, or watch. Mobile applications often stand in contrast to desktop applications which are designed to run on des ...

s 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 A memory card is an electronic data storage device used for storing digital information, typically using flash memory. These are commonly used in digital portable electronic devices. They allow adding memory to such devices using a card in a so ...

slot, or internal flash memory card and a

USB Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply (interfacing) between computers, peripherals and other computers. A broad ...

port. Some act as a

USB flash drive Universal Serial Bus (USB) is an industry standard that establishes specifications for cables, connectors and protocols for connection, communication and power supply ( interfacing) between computers, peripherals and other computers. A bro ...

, which allows

download In computer networks, download means to ''receive'' data from a remote system, typically a server such as a web server, an FTP server, an email server, or other similar system. This contrasts with uploading, where data is ''sent to'' a remote ...

ing the track log data for further computer analysis. The track list or point of interest list may be in GPX,

KML Keyhole Markup Language (KML) is an XML notation for expressing geographic annotation and visualization within two-dimensional maps and three-dimensional Earth browsers. KML was developed for use with Google Earth, which was originally named Key ...

, NMEA or other format. Most

digital camera A digital camera is a camera that captures photographs in digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film. Digital cameras are now widely incorporated into mobile devices ...

s 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 Exchangeable image file format (officially Exif, according to JEIDA/JEITA/CIPA specifications) is a standard that specifies formats for images, sound, and ancillary tags used by digital cameras (including smartphones), scanners and other syste ...

metadata in the picture file. Cameras with a GPS receiver built in can directly produce such a

geotagged photograph A geotagged photograph is a photograph which is associated with a geographic position by geotagging. Usually this is done by assigning at least a latitude and longitude to the image, and optionally elevation, compass bearing and other fields may ...

. In some private investigation cases,

data loggers A data logger (also datalogger or data recorder) is an electronic device that records data over time or about location either with a built-in Scientific instrument, instrument or sensor or via external instruments and sensors. Increasingly, but ...

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 Asset tracking refers to the method of tracking physical assets, either by scanning barcode labels attached to the assets or by using tags using GPS, BLE, LoRa, or RFID which broadcast their location. These technologies can also be used for indo ...

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 (i.e. "sends"), at regular intervals, the position of the device as well as other information like

speed In everyday use and in kinematics, the speed (commonly referred to as ''v'') of an object is the magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (ma ...

altitude Altitude or height (also sometimes known as depth) is a distance measurement, usually in the vertical or "up" direction, between a reference datum and a point or object. The exact definition and reference datum varies according to the context ...

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 A satellite navigation device (satnav device) is a user equipment that uses one or more of several global navigation satellite systems (GNSS) to calculate the device's geographical position and provide navigational advice. Depending on the ...

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

smartphone A smartphone is a portable computer device that combines mobile telephone and computing functions into one unit. They are distinguished from feature phones by their stronger hardware capabilities and extensive mobile operating systems, whic ...

s running GPS tracking software can turn the phone into a data pusher (or logger) device. As of 2009, open source and

proprietary {{Short pages monitor