This is where BLE has the advantage over previous proprietary protocols which required custom hardware, usually a USB dongle or an integrated radio, to complete the other end of the wireless communication. This, amongst other reasons like power consumption and standards-based software has caused BLE to become the de-facto choice for IoT applications.
The most popular IoT applications have so far been seen in wearable electronics (e.g. the Jawbone Up), where a device gathers sensor data, runs complex algorithms to extract meaningful information, then transmits this information to a mobile device. Similar concepts are now being adopted by home appliances and sensor modules to convert ordinary homes into smart homes. Examples of such appliances include smart coffee makers that brew coffee of your choice and have it ready as you’re ready to leave in the morning, or smart lighting control systems that detect your presence in the room and turn lights on or off automatically.
One challenge with the current implementation of the BLE standard is its limited network topology. In systems such as smart homes where you may have multiple nodes (sensors and light switches in many locations), each node has to be individually controlled by a common central device, usually a mobile phone. In this article, we take a look one novel approach as a solution to this limitation.
Consider a smart home system with multiple nodes. Each node has a sensor interface, a light control unit, and a BLE communication unit. The sensor interface can detect human presence and ambient light levels. The light control unit can turn lights on or off and also control the color temperature and intensity of the lights. The communication unit implements the BLE protocol to talk with the other nodes in the smart home system.