International Journal of Science, Engineering and TechnologyAuthors: Nalawade Sneha Sunil, Professor Bangar Abhishek Popat
Abstract: Finding people or objects inside a building is not always straightforward. GPS works well outdoors, but walls and roofs weaken its signals indoors. This creates a need for affordable systems that can identify the room or area where a person or item is located. Bluetooth Low Energy (BLE) beacons are small, battery-powered transmitters that offer one practical option. This review examines 17 sources published between 2012 and 2024 on BLE-based indoor positioning and micro-tracking. The studies are organised around positioning techniques, RSSI fingerprinting, signal filtering, machine learning, Bluetooth 5.1 direction finding, and applications in places such as museums and hospitals. Overall, fingerprinting tends to perform better than estimating position from signal strength alone. In one testbed, 95% of position estimates were within 2.6 metres when the beacons were placed relatively close together. Filtering and machine-learning methods can make estimates more stable, while Bluetooth 5.1 direction finding may support more precise positioning. However, signal strength is affected by people and the surrounding environment, and many studies test their systems at only one site for a limited period. Battery replacement, ongoing maintenance and privacy also receive less attention than accuracy. The review compares twelve representative studies, summarises recurring research gaps and suggests practical steps towards reliable systems that can operate beyond controlled experiments.
