A Journey Through the History of BLE (Bluetooth Low Energy)

 

Embark on this fascinating journey through the history of Bluetooth Low Energy, or BLE, and uncover the evolution of this revolutionary wireless technology.

What is BLE, and What Does It Stand For?

    BLE stands for Bluetooth Low Energy, often marketed as Bluetooth Smart. It's a wireless communication technology that was developed for short-range communication. While it shares some similarities with Wi-Fi, BLE is specifically designed to prioritize battery life over high-speed data transfer.

Today, most smartphones and tablets are BLE-compatible, making it easy to communicate with various devices, from wireless headphones and fitness trackers to digital signage.

How Does BLE Technology Work?

    BLE operates on a one-way communication principle. Let's take the example of BLE beacons trying to communicate with a nearby smartphone. A Bluetooth beacon device broadcasts data packets at regular intervals. These packets are detected by apps or pre-installed services on nearby smartphones, triggering actions such as sending messages or promoting an app.

To save energy and ensure higher data transfer speeds, the Bluetooth BLE communication framework comprises 40 frequency channels, with 3 primary advertisement channels and 37 secondary data channels. BLE operates in the 2.4 GHz Industrial, Scientific, and Medical (ISM) band, with a range of approximately 10 meters. It employs a frequency-hopping spread spectrum (FHSS) technique to avoid interference from other wireless devices using the same frequency band.

The BLE protocol stack is similar to classic Bluetooth, consisting of the Physical Layer (PHY), Link Layer (LL), Host Controller Interface (HCI), and the Generic Attribute Profile (GATT).

A Glimpse into the History of BLE

    BLE's history is deeply intertwined with the Bluetooth Special Interest Group (SIG). The specifications for BLE were formally announced on May 20, 1998, by the SIG, which was established by major companies like Ericsson, IBM, Intel, Nokia, and Toshiba. Over the years, the SIG has grown to include over 30,000 companies worldwide.

Now, let's dive into the history of BLE, including its various versions and their key features:

Ø  Bluetooth 1.0 and 1.0B

 

Products were not interoperable.

Anonymity was not possible, limiting certain services.

 

Ø  Bluetooth 1.1-1.2

 

Ratified as IEEE Standard 802.15.1–2002.

Fixed many errors found in the v1.0B specifications.

Added non-encrypted channels.

Introduced Received Signal Strength Indicator (RSSI).

Faster connection and discovery.

Adaptive frequency-hopping spread spectrum (AFH) improved resistance to radio frequency interference.

Achieved higher transmission speeds, up to 721 kbit/s.

Introduced Extended Synchronous Connections (eSCO) for better voice quality.

Host Controller Interface (HCI) operation with three-wire UART.

 

Ø  Bluetooth 2.0 + EDR and 2.1 + EDR

 

Introduced Enhanced Data Rate (EDR) for faster data transfer.

EDR used a combination of GFSK and phase-shift keying modulation (PSK) to achieve a bit rate of 3 Mbit/s.

Reduced power consumption through a lower duty cycle.

Introduced secure simple pairing (SSP) for improved pairing and security.

Allowed for extended inquiry response (EIR) and reduced power consumption with sniff subrating.

 

Ø  Bluetooth 3.0 + HS

 

Adopted by the Bluetooth SIG on April 21, 2009.

Provided theoretical data transfer speeds of up to 24 Mbit/s.

Introduced AMP (Alternative MAC/PHY) for high-speed transport.

Enhanced modes for L2CAP

 

Ø  Bluetooth 4.0 (Bluetooth Smart), 4.1 and 4.2

 

Adopted as of June 30, 2010 & Announced on December 4, 2013.

Included Classic Bluetooth, Bluetooth high speed, and Bluetooth Low Energy (BLE) protocols.

BLE was designed for low-power applications and significantly extended battery life.

Introduced new features, including increased co-existence support for LTE and improved data exchange rates.

Focused on Internet of Things (IoT) technology.

Introduced features like Low Energy Secure Connection and enhanced privacy

 

Ø  Bluetooth 5

 

Released on December 6, 2016.

Introduced options to double speed or quadruple range.

Enhanced capacity for connectionless services.

 

Ø  Bluetooth 5.1, 5.2, 5.3 and 5.4

 

Presented on January 21, 2019 to February 2023.

Introduced features like Angle of Arrival and Angle of Departure for device tracking.

Introduced Enhanced Attribute Protocol, LE Power Control, and LE Isochronous Channels.

Introduced Bluetooth Low Energy Audio (BT LE Audio) for lower battery consumption in audio transmission.

These are the significant milestones in BLE's history, and it's incredible to see how it has evolved and adapted to meet the demands of various applications. In our next blog post, we'll continue exploring BLE's journey, including its impact on the world of wireless communication and the Internet of Things.