Demystifying Bluetooth Indoor Positioning

What is Bluetooth Indoor Positioning?

Bluetooth indoor positioning relies on RSSI (Received Signal Strength Indication), which measures signal field strength, and operates on the principle of triangulation.

Positioning Methods

Bluetooth positioning encompasses two primary methods: network-side positioning and terminal-side positioning.

Network-side Positioning:

The network-side system comprises low-power Bluetooth terminals (e.g., mobile phones), Bluetooth beacon nodes, Bluetooth gateways, wireless local area networks, and back-end data servers. The process involves:

1. Deploying beacons and Bluetooth gateways in the designated area.

2. When a terminal enters the beacon signal's coverage, it senses the broadcast signal and calculates the RSSI value under a beacon. This value is then transmitted to the back-end data server through the Bluetooth gateway via the Wi-Fi network. The server's built-in positioning algorithm determines the terminal's precise location.

Terminal-side Positioning:

The terminal-side system includes terminal devices (e.g., mobile phones with embedded SDK software) and beacons. The process is as follows:

1. Installing Bluetooth beacons throughout the area.

2. Beacons continuously broadcast signals and data packets.

3. When a terminal device enters the beacon signal's range, it measures its RSSI value under different base stations and calculates the specific location using the mobile phone's built-in positioning algorithm.

Terminal-side positioning is commonly used for indoor positioning, navigation, and location-based marketing, while network-side positioning finds applications in personnel tracking, asset positioning, and passenger flow analysis. Bluetooth positioning is advantageous for its simplicity, with accuracy tied to Bluetooth beacon density and transmission power. It is also highly power-saving, employing features like deep sleep, connection-free operation, and simple protocols to optimize energy consumption.