Generally tracking is the observing of persons or objects on the move and supplying a timely ordered sequence of respective location data to a model e.g. capable to serve for depicting the motion on a display capability.
Tracking in virtual space
In virtual space technology, a tracking system is generally a system capable of rendering virtual space to a human observer while tracking the observer's body coordinates. For instance, in dynamic virtual auditory space simulations, a real-time head tracker provides feedback to the central processor, allowing for selection of appropriate head-related transfer functions at the estimated current position of the observer relative to the environment.
Tracking in real world
Within the real world, there are a variety of technologies employed within asset tracking systems. Some are 'lag time' indicators, that is, the data is collected after an item has passed a point for example a bar code or choke point or gate. Others are 'real-time' or 'near real-time' like Global Positioning Systems depending on how often the data is refreshed. There are bar-code systems which require a person to scan items and automatic identification (RFID auto-id). For the most part, the tracking worlds are composed of discrete hardware and software systems for different applications. That is, bar-code systems are separate from Electronic Product Code (EPC) systems, GPS systems are separate from active real time locating systems or RTLS for example, a passive RFID system would be used in a warehouse to scan the boxes as they are loaded on a truck - then the truck itself is tracked on a different system using GPS with its own features and software. The major technology silos in the supply chain are:
Indoors assets are tracked repetitively reading e.g. a barcode, any passive and active RFID and feeding read data into Work in Progress models (WIP) or Warehouse Management Systems (WMS) or ERP software. The readers required per choke point are meshed auto-ID or hand-held ID applications.
However tracking could also be capable to provide monitoring data without binding to fixed location by using a cooperative tracking capability, e.g. an RTLS.
Outdoors mobile assets of high value are tracked by choke point, 802.11, Received Signal Strength Indication (RSSI), Time Delay on Arrival (TDOA), active RFID or GPS Yard Management; feeding into either third party yard management software from the provider or to an existing system.
Fleet management is applied as a tracking application using GPS and composing tracks from subsequent vehicle's positions. Each vehicle to be tracked is equipped with a GPS receiver and relays the obtained coordinates via cellular or satellite networks to a home station. Fleet management is required by:
- Large fleet operators, (vehicle/railcars/trucking/shipping)
- Forwarding operators (containers, machines, heavy cargo, valuable shippings)
- Operators who have high equipment and/or cargo/product costs
- Operators who have a dynamic workload
Mobile phone services
Location-based services or LBS is a term that is derived from the telematics and telecom world. The combination of A-GPS, newer GPS and cellular locating technology is what has enabled the latest LBS for handsets and PDAs. Line of sight is not necessarily required for a location fix. This is a significant advantage in certain applications since a GPS signal can still be lost indoors. As such, A-GPS enabled cell phones and PDAs can be located indoors and the handset may be tracked more precisely. This enables non-vehicle centric applications and can bridge the indoor location gap, typically the domain of RFID and RTLS systems, with an off the shelf cellular device.
Currently, A-GPS enabled handsets are still highly dependent on the Location-Based Service (LBS) carrier system, so handset device choice and application requirements are still not apparent. Enterprise system integrators need the skills and knowledge to correctly choose the pieces that will fit the application and geography.
Regardless of the tracking technology, for the most part the end-users just want to locate themselves or wish to find points of interest. The reality is that there is no "one size fits all" solution with locating technology for all conditions and applications.
Application of tracking is a substantial basis for vehicle tracking in fleet management, asset management, individual navigation, social networking, asset management, or mobile resource management and more. Company, group or individual interests can benefit from more than one of the offered technologies depending on the context.
GPS has global coverage but can be hindered by line-of-sight issues caused by buildings and urban canyons. RFID is excellent and reliable indoors or in situations where close proximity to tag readers is feasible, but has limited range and still requires costly readers.
Real-time Locating Systems (RTLS)
RTLS are enabled by Wireless LAN systems (according to IEEE 802.11) or other wireless systems (according to IEEE 802.15) with multilateration. Such equipment is suitable for certain confined areas, such as campuses and office buildings. RTLS require system-level deployments and server functions to be effective. RTLS systems are affordable and accurate for industrial and yard applications. RTLS systems are not appropriate for all indoor applications, there fuzzy locating systems with unilateration may apply more economically.