The basics of Bluetooth Low Energy (BLE): Page 4 of 7

October 20, 2016 //By Abhishek Gupta and Imran Mohammed, Cypress Semiconductor
Bluetooth technology has revolutionized wireless communications between devices with its ubiquitous and simple characteristics. It allows devices to communicate without cables while maintaining high levels of security. Because of its low power and low cost, Bluetooth has played a pivotal role in the evolution of applications from high-speed automotive devices to complex medical devices.

Wireless co-existence – Bluetooth technology, Wireless LAN, IEEE 802.15.4/ZigBee, and several proprietary radios use the license-free 2.4 GHz Industrial Scientific Medical (ISM) band. With so many technologies sharing the same radio space, interference can decrease wireless performance (i.e., increasing latency and decreasing throughput) due to the need for error correction and retransmission. In demanding applications, interference can be reduced through frequency planning and special antenna design. As both classic Bluetooth technology and BLE technology utilize AFH, which minimizes interference with other radio technologies, Bluetooth transmission is robust and reliable.

Connection range – BLE technology has a slightly different modulation from classic Bluetooth technology. This modulation differentiation offers a range of up to 300 metres with a 10 dBm radio chipset (BLE maximum).

Ease of use and integration – A BLE piconet is typically based on a master connected to a number of slaves. A device is either a master or a slave, but never both. The master controls how often the slaves are allowed to communicate, and the slave only communicates by request from the master. A new feature BLE adds compared to classic Bluetooth technology is “advertising” functionality. With this feature, a device acting as a slave can announce that it has something to transmit to the master. An advertisement message can also include an event or a measurement value.

 

Design category: