How the know-how has developed

Over a remarkably brief period, Bluetooth has evolved from a niche wireless protocol to an omnipresent technology that underpins our daily lives, enabling seamless connectivity between devices ranging from headphones to smart home appliances. Bluetooth has become the go-to standard for short-range wireless communication, rivaled only by WiFi in terms of popularity and versatility.

While Bluetooth may initially appear as a relatively secure and uninspiring technology at face value, the protocol has actually undergone significant transformations over the years. Although some earlier Bluetooth versions’ benefits still haven’t been fully incorporated into our devices.

Luckily, our devices seamlessly support multiple Bluetooth variants, automatically selecting the best one based on availability and usage scenarios. However, what’s the difference between each major and minor Bluetooth version and which one is the most recent? Here’s everything you need to know.

Without delving too deeply into the technology, the concept was originally conceived to integrate mobile connectivity within laptops. By the late 1990s, IBM and Ericsson’s engineering teams discovered that seamlessly integrating a cell phone directly into a laptop was impractical due to the device’s power requirements. As a last resort, the team decided to rely on Ericsson’s established low-power communication protocol, which had been under development since 1994. The researchers hypothesized that this technological advancement could potentially empower phones and laptops to communicate seamlessly across short distances.

IBM and Ericsson jointly shared their technology expertise with various companies, thereby inaugurating the Bluetooth Special Interest Group (SIG). The Special Interest Group (SIG) introduced the first Bluetooth standard in 1999, showcasing its capabilities through a hands-free phone application. Despite this, no existing telephone on the market possessed the technological capabilities present at that time. In 2001, the first commercially available phone with built-in Bluetooth technology was launched, a mere two years after its initial introduction.

Despite this, Ericsson developed Bluetooth 1.0 as an alternative to Wi-Fi and the RS-232 standard, which was a common feature in computers at the time? The RS-232 serial cable had long been a ubiquitous component, facilitating connections between peripherals such as mice and keyboards, as well as modems for dial-up internet access. Despite this, the ports had loomed large and imposing in scale.

In its 1999 debut, Bluetooth’s early iteration already demonstrated a remarkable affinity for providing a versatile and energy-efficient solution for wireless device pairing. The initial driver of innovation was the pursuit of comfort, a need that has persisted and is now being revolutionized by wireless earbuds’ seamless integration with smartphones.

The initial Bluetooth standard had limitations such as slow data transfer rates and a maximum operating range of just 10 metres.

The second generation of Bluetooth technology debuted in 2004, boasting several highly anticipated enhancements, with the most notable addition being Enhanced Data Rate (EDR), which significantly improved data transmission speed. The advancements facilitated a maximum speed of up to 3 Mbps, opening the door to innovative applications such as wireless audio transmission. This functionality allowed for seamless connectivity between a single laptop and multiple devices at once, facilitating the simultaneous use of a Bluetooth keyboard, mouse, and printer.

Bluetooth 2.0 enabled longer transmission range compared to its predecessor. It boasted a maximum variety of 30 meters, three times that of the original standard.

In 2007, Bluetooth 2.1 introduced a groundbreaking innovation – Safe Easy Pairing (SSP), revolutionizing the pairing process to deliver a significantly enhanced user experience and unparalleled connectivity security. If you’ve previously encountered SSP while confirming a PIN for paired Bluetooth devices, Prior to the release of Bluetooth 2.1, this offered a more secure alternative to traditionally insecure mounted PINs, such as the ubiquitous “0000”, which had long been used for pairing purposes.

Introduced in 2009, Bluetooth 3.0 revolutionized data transfer with the introduction of Enhanced Power (EP), a non-mandatory feature that significantly boosted transmission speeds thanks to its High-Speed (HS) capabilities. By allowing Bluetooth devices to achieve data transfer rates of up to 24 Mbps, there was a significant caveat: this rapid data transfer would not occur directly over the Bluetooth link itself? Bluetooth enables seamless pairing and communication, whereas more complex knowledge transfer occurs over Wi-Fi networks instead?

After all, the excessive velocity of knowledge transfer requires gadgets to integrate both Bluetooth and Wi-Fi hardware seamlessly. Despite their existence, few manufacturers had previously incorporated this feature into their products. The lack of a mandatory high-speed (HS) component in Bluetooth 3.0’s specification hindered its overall effectiveness, further exacerbated by the absence of a reliable means to prioritize data transmission over other devices.

Despite introducing substantial advancements, Bluetooth 3.0 ultimately garnered significantly less recognition compared to other versions, leaving it overshadowed by its peers? Enabling Enhanced Energy Management, a breakthrough innovation streamlined energy administration by optimizing device performance across varying power levels and minimizing unnecessary battery depletion.

By the time Bluetooth 4.0 was introduced and ratified by the Bluetooth Special Interest Group (SIG), the technology had become ubiquitous on portable devices. Despite these advancements, battery life remained a significant concern as the technology enabled data transmission between devices over extended periods of time? At that point in time, the concept of perpetual wearability and wireless connectivity through devices like Bluetooth earbuds was still on the distant radar.

To facilitate its objectives, the Bluetooth Special Interest Group decided to diverge the development of this knowledge into two distinct trajectories. Traditional Bluetooth remained largely unchanged from its predecessors, without significant updates to the protocol. Despite this, the 4.0 launch also introduced a new feature, specifically designed for low-power devices to maintain connectivity while minimizing power consumption as much as possible?

Bluetooth Low Energy enables devices to transmit small amounts of data in short intervals, ideal for applications like wearables syncing step count information with a phone. Later revisions, such as Bluetooth 4.2, incorporated privacy and security upgrades specifically designed for the smart home industry, enabling sensors to communicate trigger-based actions like motion detection seamlessly. Notwithstanding this, the latter did not gain traction – the vast majority of smart home products instead utilize competing wireless standards such as Zigbee over BLE.

Notwithstanding its humble beginnings, Bluetooth Low Energy (BLE) has truly been a game-changer. The know-how was designed to operate effectively for extended periods of time – up to several months or even years – using the power of a reliable button cell. This breakthrough innovation enabled the mass production of innovative devices featuring high-quality components. While devices supporting both Bluetooth Traditional and LE variants can coexist seamlessly, allowing for effortless switching between them when needed.

Introduced in 2016, Bluetooth 5 solidified its position as the dominant standard. The Special Interest Group (SIG) concurrently refined Bluetooth Traditional and Low Energy (LE), enabling each department to leverage distinct benefits.

Transmissions over Bluetooth 5 low-power links can potentially achieve speeds up to two megabits per second, a significant increase from previous technologies. Under optimal conditions, gadgets may compromise on knowledge velocity to reach distances four times greater, reaching up to 240 metres beneath their normal range. Bluetooth 5 introduced a new level of bandwidth flexibility, allowing devices to dynamically allocate resources to prioritize either long-range transmission at reduced power consumption or high-speed data transfer. The potential exists to develop new technologies that would enhance audio quality, simultaneously taking advantage of the low energy efficiency offered by Bluetooth Low Energy (BLE).

In 2019, the launch of Bluetooth 5.1 introduced Route Discovering, enabling precise tracking down to a few centimeters. While GPS tracking has become a standard feature in many fitness devices, Bluetooth is increasingly being utilized for coarser monitoring applications.

LC3 codec and Auracast

Just over a year after its introduction, we observed the release of Bluetooth 5.2 and the establishment of the LE Audio standard. The latter included a completely innovative . LC3 enables superior audio quality at reduced bitrates, while also leveraging Bluetooth Low Energy’s (BLE) low power consumption capabilities.

By 2020, true wireless earbuds, following in the footsteps of Apple’s pioneering AirPods, had already begun to gain significant traction. Despite its age, the traditional Bluetooth SBC codec falls short of delivering exceptional audio quality, leaving much room for improvement. LC3 enables higher-quality video transmission at lower bitrates while simultaneously extending battery life.

Bluetooth 5.2 introduces support for audio broadcasting, also known as Auracast. The functionality allows for seamless audio streaming from a single Bluetooth source to multiple receivers, simplifying the process of sharing music with friends and family. Does this imply that you might stream audio from your phone directly to your friend’s earbuds while also listening through your own earphones? The new feature also enables seamless integration with hearing aids, envisioning the use of Auracast to broadcast audio from a single source to multiple hearing aids distributed across a large venue such as a theater or stadium, facilitating effortless sound transmission for all attendees?

Bluetooth 5.3 and 5.4, respectively launched in 2021 and 2023, brought significant advancements with the introduction of enhanced stability and connectivity features. While previous updates may have focused on incremental advancements without fanfare, Bluetooth 5.4 introduces a significant innovation: support for Periodic Advertising with Responses (PAwR). The function enables a solitary Bluetooth beacon to simultaneously transmit messages to up to 7,000 devices directly. The place is this convenient? In many large retail establishments that have opted for digital shelf labels, often utilizing electronic ink technology. Previous Bluetooth iterations necessitated a round-trip communication approach for each update, potentially resulting in slower refresh rates in larger retail environments.

After nearly a decade of incremental enhancements and minor model updates, the Bluetooth Special Interest Group (SIG) finally unveiled its next major Bluetooth technology on August 27, 2024. Bluetooth 6.0 is now officially the latest version available, but it will take some time for consumer devices to adopt this new standard.

Bluetooth 6.0’s notable innovation is Bluetooth Low Energy (BLE) direction-finding, enabling devices to accurately estimate their physical distance from each other through a feature called Bluetooth Channel Sounding. Prior generations often relied on the estimation of sign energy to approximate distance, a method that proved insufficient for creating reliable locks and automotive keys. Bluetooth Channel Sounding leverages a combination of round-trip time (RTT) and phase-based ranging (PBR) technologies to ensure accurate distance calculations, similar to Ultra-Wideband (UWB).

Nowhere else does Bluetooth 6.0 introduce further safeguards and efficiency upgrades, along with reduced latency, specifically benefiting audio applications. Bluetooth 6.0-enabled devices are expected to debut as early as 2025.

Despite the current limitations, it’s possible that within the next 1-2 years, we may see the adoption of innovative technologies like Bluetooth Channel Sounding. As the tech landscape evolves, features from previous eras like Auracast are finally gaining traction in modern devices, including the recently released and the Bluetooth audio sharing functionality in.