From Cable Replacement to the IoT: Bluetooth 5.1

The Bluetooth® wireless standard has found its way into virtually all smartphones, PCs, cars, entertainment hardware and wearables. Bluetooth SIG reports that more than 8 billion devices are currently in use. Bluetooth supports Internet of Things (IoT) technologies and direction finding methods, ensuring its relevance for the foreseeable future as well.

This white paper summarizes the various Bluetooth technologies with a focus on the physical layer in line with core specification version 5.1.

Introduction

Bluetooth, named after a 10th century Danish king, was originally developed in the 1990s as a replacement for cable connections (e.g. a keyboard or smartphone to a PC). Initially, the objective was to cover a limited area (about 10 m) with moderate data rates and low energy consumption. A new version in the early 2000s tripled the data rate, and in 2010 a new specification additionally provided support for small battery-operated (“button-cell”) devices such as sensors.

Bluetooth is a ubiquitous wireless standard in the consumer sector and has found its way into every computer and smartphone. The industry has also devised additional opportunities such as beacons for positioning and automation. The advent of fitness trackers and smartwatches further drives the Bluetooth market.

This white paper primarily focuses on the physical layer.

Chapter 2 provides a general overview and explains the most important concepts and the individual versions. The chapters 3 and 4 provide detailed descriptions of the two main variants, Bluetooth Classic and Bluetooth Low Energy (LE) and highlights version 5 features. The final chapter summarizes and compares the characteristics of both variants.