BLE was initially incorporated into the Bluetooth 4.x protocol. Limitations of BLE over the last decade were that it had a slow data transfer speed and a short transmission distance. With the rollout of Bluetooth 5 a couple of years ago, these limitations have been mitigated, and, as a result, we’ll see BLE become even more ubiquitous. The Bluetooth 5 protocol improves BLE by 4x the range, 2x the data transfer speed, and 8x the broadcasting message capacity. Additionally, Bluetooth 5 released the ability for the BLE protocol to create mesh networks. The ability to have a mesh topology has significantly increased the applications available for BLE. (e.g. consider the application of smart lighting in a large commercial building. A mesh topology allows signals to “jump” from one lightbulb to the next to reach all the lights in the building. Without the mesh topology, there would have to be transmitting gateways spread throughout the building to reach all the lights, adding significant installation cost.)
For product developers that are considering using BLE in their product, some of the considerations and topics to familiarize oneself with are:
- Whether to use a pre-certified BLE module or to use a chipset-up design. The former option has a higher per-unit cost, but the latter requires more upfront development time and cost.
- The nuances of the BLE SIG protocol to create “Bluetooth LE services” for your product.
- The tradeoffs of how different BLE features - advertising, broadcasting, beaconing, indicating, etc - affect product usability and battery life.
- The process of implementing OTA (Over The Air) update capability to the BLE device so that firmware can be updated post product deployment.
BLE is already widespread and it will continue to be a highly popular and reliable connectivity protocol for many years to come. It is often a wise choice to integrate BLE into a new IoT product. The process of designing, programming, and certifying a new BLE product, however, can be vexing to those who are new to the protocol. For those seeking deeper guidance on the BLE protocol and how to incorporate it into new products, 219 Design is a great resource.