Hardware Reference
In-Depth Information
CHAPTER 1
Introduction
Bluetooth Low Energy (BLE, also marketed as Bluetooth Smart) started as part of the
Bluetooth 4.0 Core Specification. It's tempting to present BLE as a smaller, highly opti‐
mized version of its bigger brother, classic Bluetooth, but in reality, BLE has an entirely
different lineage and design goals.
Originally designed by Nokia as Wibree before being adopted by the Bluetooth Special
Interest Group (SIG), the authors weren't trying to propose another overly broad wire‐
less solution that attempts to solve every possible problem. From the beginning, the
focus was to design a radio standard with the lowest possible power consumption,
specifically optimized for low cost, low bandwidth, low power, and low complexity.
These design goals are evident through the core specification, which attempts to make
BLE a genuine low-power standard, designed to actually be implemented by silicon
vendors and used in the real world on a tight energy and silicon budget. It might be the
first widely adopted standard that can realistically lay claim to running for an extended
period of time off a humble coin cell, though many other wireless technologies regularly
make that claim in their marketing.
What Makes BLE Different
While Bluetooth Low Energy is a good technology on its own merit, what makes BLE
genuinely exciting—and what has pushed its phenomenal adoption rate so far so quickly
—is that it's the right technology, with the right compromises, at the right time. For a
relatively young standard (it was introduced in 2010), BLE has seen an uncommonly
rapid adoption rate, and the number of product designs that already include BLE puts
it well ahead of other wireless technologies at the same point of time in their release
cycles.
Compared to other wireless standards, the rapid growth of BLE is relatively easy to
explain: BLE has gone further faster because its fate is so intimately tied to the
