UUID – universally unique identifier that identifies the device to the receiver They all define broadcast messages that include at the minimum the following information:

There are different popular beacon protocols. Smartphones are capable of scanning for these signals and pass them to the registered applications. The additional could include URL or another relevant payload. The messages typically include some sort of identifier and additional “useful” information. It is configured to constantly broadcast messages. This functionality enabled many use cases:Īccess control (Tesla uses BLE for the smartphone-based car key)Ī beacon is a small battery powered Bluetooth Low Energy (BLE) radio transmitter. As this standard has not yet made into the smartphones, the current micro-location solutions must use Bluetooth 4/5 standard that is based on RSSI measurements. This value can be used to approximate distance and when measurements from multiple devices are combined, the device position can be estimated with accuracy of 1 to 4 meters (3 to 12 feet).Īs described in Part 3 of this blog, with Bluetooth 5.1 standard the accuracy could be further enhanced by using direction-finding capabilities of the devices. As part of the broadcast message decoding, the BLE software stacks return the Received Signal Strength Indicator (RSSI) value. This enables devices to quickly identify each other without user’s intervention. In addition to extending the battery life dramatically, one of the big improvements of BLE over Classic Bluetooth is that the devices can broadcast short messages in a connectionless fashion, i.e. devices do not need to be paired. In addition, there are many low-cost beacons available from multiple vendors that support BLE and can be used to create micro-location solutions.īLE is also used by the recently released contact-tracing framework by Google and Apple.

That is why it is one of the most widely used smartphone based micro-location technologies. Bluetooth Low Energy (BLE) is a standard defined by the Bluetooth Special Interest Group. BLE is independent of Classic Bluetooth and the two can coexist. The standard was officially published in December 2009 as part of Bluetooth 4.0 specification.īLE is currently supported by all modern smartphones and operating systems (iOS, Android).

Bt rssi