Bluetooth Low Energy (BLE)-Learn the Basics in Under 5 Minutes

BLE or Bluetooth Low Energy is a form of wireless area network technology that has been designed by the Bluetooth Special Interest Group or Bluetooth SIG. Bluetooth Low Energy has been developed for unique and innovative applications in the fields of medicine, security, beacon, fitness, and entertainment. Bluetooth Low Energy provides the same connectivity features like typical Bluetooth but consumes far less energy. It also doesn’t sacrifice on the range of the connection. 

All kinds of smartphone platforms such as Android, iOS, Windows Phone, Blackberry and PC platforms like Microsoft Windows, Mac and Linux support Bluetooth Low Energy. The Bluetooth SIG predicts that by the need of the year 2018, more than 90% of all Bluetooth devices will run using Bluetooth Low Energy.

Features of Bluetooth Low Energy

Bluetooth Low Energy is not backwards compatible with the previous version of Bluetooth, also known as classic Bluetooth. It uses the same 2.4 GHz radio frequency which is used by the classic Bluetooth and allows single antennae for dual purpose (radio as well as Bluetooth). The modulation system used by BLE is much simpler than the one used by classic Bluetooth.

The work on Bluetooth Low Energy started in 2001 when Nokia noted down various scenarios that were not addressed by traditional connectivity measures. Added to this, the current standard of Bluetooth back then was also worked upon. The new findings were published by the name of Bluetooth Low-End Extension. Logitech also independently developed a Bluetooth technology known as STMicroelectronics which reduces the power consumption of Bluetooth modules. The technology was released to the public in October 2006 by the name of Wibree. After many negotiations, an agreement was reached between Bluetooth SIG and Wibree to include STMicroelectronics as a part of Bluetooth ultra-low power technology.

Profiles of application

Several application profiles have been developed for Bluetooth Low Energy which has also been borrowed from classic Bluetooth. The new Bluetooth module finds use in low energy devices and systems. Most Bluetooth connections use the Generic Attribute Profile (GATT) with the exception of Bluetooth mesh. Applications based on Bluetooth mesh profiles use GAP or General Access Profile. 

Bluetooth Mesh profiles use BLE to communicate with other BLE devices connected on the network. Any kind of information can be transmitted to other Bluetooth Low Energy devices down the line which creates a mesh-like effect. An example of the mesh effect profile is a Bluetooth switchboard which can control the lights of the entire building. In the healthcare industry, there are three major types of profiles used. Blood pressure profile is used for blood pressure measurement, and there are thermometric profiles for measuring temperature and glucose monitors. 

While Bluetooth Low Energy uses the same radio frequency as Bluetooth classic, it uses a different set of channels for communication. Instead of using the classic Bluetooth 79 1-MHz, the Bluetooth Low Energy channel uses 40-2MHz channels. Frequency hopping is used by BLE to overcome narrow-band interference problems.