The evolution of wireless communications technology has brought about a revolution in the wireless tracking field. There is a proliferation of products designed to track assets and personnel using wireless technology. Some of these products have been quietly deployed and are already part of people's daily lives. There is a growing need to track the location and movement of valuable assets and items, due to various reasons, such as security and improvements in productivity. "Tracking technologies are used in applications ranging from plant and animal tracking, to freight management, to tracking for crime prevention and other social reasons," explains CSIR information communication technology (Icomtek) unit telecomms analyst Albert Gazendam.

Wireless tracking is best divided into two categories: identification and position tracking. Identification systems identify items within a limited range, whereas tracking systems determine the position of items.

Asset identification has been dominated by barcode technology for a long time. However, there has recently been increasing interest in radio identification systems. The prominent technology in this area is radio frequency identification (RFID). First used commercially at the beginning of the 1960s for electronic article surveillance to counter theft, RFID has been adopted as a basic wireless tracking identification standard worldwide.

Emerging high-performance active tag products operate within the 2,45 GHz industrial, scientific, and medical (ISM) band while their passive counterparts have been proposed for operation within disjointed ultrahigh-frequency bands that have not yet been harmonised across the world. "It is expected that these active-tag technologies will be both conscious of and considerate to the other communication system standards that currently operate within the ISM band," says CSIR Icomtek telecomms analyst Phemelo Baholo. There are other potential identification technologies, namely infra-red data association (IrDA) and Bluetooth. IrDA is a communication standard based on infra-red light. It is commonly used in mobile devices for less-expensive point-to-point communication. Bluetooth is a low-cost, low-power, short-range radio technology developed originally as a cable-replacement technology. These communication technologies have built-in discovery protocols, which make them suitable for identification tracking purposes.

In terms of positioning tracking, global positioning system (GPS) tracking systems use satellites to pinpoint the location of a tracked object and can locate an object anywhere in the world. Assisted GPS (A-GPS) is newly-improved GPS that can be used to pinpoint mobile devices. This method was created to improve accuracy to some centimetres, by using conventional GPS together with wireless networks, such as global system mobile (GSM), to improve performance.

Mostly used in animal tracking, RF tracking also includes telemetry to determine information about an animal. Most radio tracking systems involve transmitters tuned to different frequencies (analogous to different AM/FM radio stations) that allow individual identification.

The wireless Ethernet standard (802.11b) and Bluetooth can also be used to accurately locate mobile devices in small areas like homes and business premises. Two techniques to locate mobile devices are distance-measurement technology and location-finding technology.

The location-based services market is still in its infancy, and is expected to boom with the rollout of third generation (3G) networks. Knowledge of the position of a given subscriber making a call is of particular interest to mobile operators, who can in turn provide innovative lucrative location-based services with the help of third parties.

Although wireless tracking is growing and gaining acceptance, the technology still poses serious legal concerns in some cases. Personal privacy is potentially threatened by location-based services in two main ways. These are the ability of unauthorised surveillance and the creation of databases containing detailed individual profiles. Wireless tracking has been adopted in many countries because of the need for asset security and management. Vehicle-tracking and fleet- management services are some of the prominent applications in the market today. The development of modern GSM and 3G cellular networks has triggered the development of location-based services which, with the convergence of wireless local-area networks, Bluetooth and cellular communication, is going to play a significant role in future tracking applications.

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