Wi-Fi Positioning
A positioning technology using existing Wi-Fi infrastructure for location determination. Typically uses RSSI fingerprinting or trilateration based on access point signals. Lower accuracy (3-10 meters) than UWB but leverages existing infrastructure reducing cost. Suitable for applications not requiring precision.
Wi-Fi positioning is an indoor location technology that determines device positions using received signal strength (RSSI) measurements from existing Wi-Fi access points (APs), offering lower-cost but less accurate positioning compared to dedicated RTLS technologies like UWB. Wi-Fi positioning accuracy typically achieves: 3-10 meters in favorable conditions (open spaces, dense AP deployment, minimal interference), 5-15 meters in typical commercial buildings, degrading significantly in industrial environments with metal structures, machinery, and interference. Wi-Fi positioning disadvantages and limitations include: limited accuracy (3-15 meters vs. 10-30 cm for UWB) inadequate for applications requiring precise positioning, RSSI instability with signal strength varying significantly from interference, multipath, people movement, and environmental changes, fingerprinting overhead requiring extensive site surveying and database creation, plus periodic updates as environments change, high positioning latency (typically 2-10 seconds vs. sub-second for dedicated RTLS), interference sensitivity to other 2.4 GHz devices (Bluetooth, microwave ovens, other Wi-Fi networks) affecting positioning reliability, and limited scalability with standard Wi-Fi struggling to support high-density tag populations.
Comparing Wi-Fi positioning to dedicated RTLS technologies: vs. UWB - Wi-Fi offers lower infrastructure cost but 10-50× less accuracy (meters vs. centimeters), slower updates (seconds vs. sub-second), and lower reliability in industrial environments. vs. BLE beacons - comparable accuracy (both 3-10 meters) but BLE typically lower cost for large deployments (inexpensive beacons vs. Wi-Fi APs) and better battery life for mobile tags. vs. RFID - Wi-Fi provides continuous tracking vs. RFID's checkpoint detection, but RFID offers lower tag cost and better penetration of metal environments.