edVirtus Reference

What Is a Real-Time Location System?

How Does an RTLS Determine the Location of People and Assets?

A Real-Time Location System (RTLS) is a technology that automatically determines and monitors the location of people, vehicles, equipment, or other assets within a defined area. RTLS is widely used in hospitals, warehouses, factories, airports, office buildings, and industrial facilities where knowing the real-time location of important assets improves operational efficiency, safety, and security.

The basic principle is straightforward. Small electronic tags are attached to the objects or carried by the people being tracked. These tags communicate with fixed receivers or reference points installed throughout the facility using wireless technologies such as Bluetooth Low Energy (BLE), Ultra-Wideband (UWB), Wi-Fi, Radio Frequency Identification (RFID), or Zigbee. By measuring signal characteristics—such as received signal strength (RSSI), time of flight, time difference of arrival (TDoA), or angle of arrival (AoA)—the system estimates the position of each tag and displays it on a digital map.

A useful analogy is an indoor air traffic control system. Just as controllers continuously monitor the location of every aircraft within an airport's airspace, an RTLS continuously monitors the location of people and assets within a building or campus, allowing their positions to be viewed in real time.

The accuracy of an RTLS depends on the positioning technology employed. Systems based on Wi-Fi or Bluetooth RSSI typically provide location accuracy of several metres, which is adequate for room-level tracking. Ultra-Wideband (UWB) systems can routinely achieve accuracies of 10–30 centimetres, making them suitable for locating medical equipment, autonomous vehicles, industrial robots, and other assets requiring precise positioning. Passive RFID systems generally indicate that an object has passed a particular reader rather than providing continuous location information.

RTLS has numerous applications. Hospitals use it to locate infusion pumps, wheelchairs, and patients. Warehouses track pallets and forklifts. Manufacturing plants monitor tools, components, and automated guided vehicles (AGVs). Office buildings use RTLS for security, occupancy management, and emergency evacuation, while sporting events employ similar technologies to track athlete movement and performance.

It is important to distinguish RTLS from GPS. GPS provides global positioning by receiving signals from satellites and works best outdoors with a clear view of the sky. RTLS, by contrast, relies on locally installed infrastructure and is specifically designed to provide reliable positioning indoors, where satellite signals are often weak or unavailable. Likewise, RTLS differs from simple asset identification systems, such as barcode scanners, because it continuously determines an asset's location rather than merely recording its presence at a single point.

Today, Real-Time Location Systems have become an essential component of modern digital infrastructure. As wireless technologies such as UWB, BLE, and Wi-Fi continue to improve in accuracy and power efficiency, RTLS is enabling smarter factories, hospitals, warehouses, and office environments by providing continuous visibility of people, equipment, and valuable assets.