Bluetooth is a type of wireless connection that is used in modern smartphones and wireless devices. It replaced the infrared rays used to transfer data in older cellphones. Through the years, Bluetooth versions have improved in order to offer faster, more secure wireless connections.
Current smartphones use Bluetooth 5.0, which is the latest Bluetooth iteration. Older devices from 2010 to 2016 may have variations of Bluetooth 4.0. Bluetooth 3.0 or lower is considered obsolete.
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What is Bluetooth?
Bluetooth is a type of wireless technology that was developed in the 1990s. Bluetooth allows compatible electronic devices to connect and transfer data using a bidirectional data transfer protocol.
Bluetooth can connect up to seven devices, which includes smartphones, consoles, and peripherals, without interference due to frequency hopping. This process assigns unique connections called piconet between each device to eliminate the potential for interference.
However, it can only connect short distances of 10-100 meters due to the 1mW of power consumption that powers the 2.4GHz bandwidth. This is one of the main disadvantages of Bluetooth however, it also provides security against potential eavesdropping, making the chances of external interference lower than other wireless connections.
Usually, compatible Bluetooth devices (printers, headsets, keyboards, mice, etc) can connect automatically once paired. The rate of transfer, however, can vary depending on the distance. Bluetooth transfer rate is known to be relatively slow when compared with wired connections.
The Bluetooth Special Interest Group (SIG) governs the development of the Bluetooth standard and provides and manages licensing for product manufacturers.
Bluetooth 1.0, 1.1, and 1.2
Bluetooth 1 was the first iteration of the Bluetooth connection. It suffered setbacks in its deployment, specifically in terms of reliability as a network connection and its interoperability between devices. The 1.1 update boasted more reliable connections and backward compatibility features which were carried out into the succeeding Bluetooth versions.
Bluetooth 1.2, moreover, increased connection speed, and data transfer rate. Its pairing speed with other compatible Bluetooth devices was increased to 720KBps and it used adaptive frequency hopping (AFH) technology to prevent interference with signals and waves of similar 2.4 to 2.8GHz frequencies like Wi-Fi and microwaves.
Both Bluetooth 1.1 and 1.2 were significant improvements over Bluetooth 1.0. Its improvements were used as standards for a wireless connection for the next Bluetooth versions.
Bluetooth 2.0 and 2.1
Bluetooth 2.0 used a data transfer rate of 1Mbps while also incorporating Oler Sub rating technology which reduced the overall energy requirements of the Bluetooth connection.
Bluetooth 2.0 then added an enhanced data rate (EDR) which increased data transfer speed from 1Mbps to theoretical speeds of 3Mbps and practical speed of 2.1Mbps.
The Bluetooth 2.1 update improved pairing through the Secure Simple Pairing (SSP) process where-in pairing between Bluetooth devices became faster and more reliable. It was also made more secure through improved data filtering.
Bluetooth 3.0 provided significant improvements on data transfer speeds from the previous Bluetooth versions. This Bluetooth version is popularly called Bluetooth 3.0 High Speed (HS) which provided data transfer speeds of up to 24Mbps.
The technology behind the significant upgrade in data transfer speeds was the incorporation of Wi-Fi technology. Bluetooth 3.0 used a Bluetooth connection to pair devices but switched over to Wi-Fi for data transfer.
Aside from the improvement in data transfer speeds, it also improved power management through the enhanced power control. This feature allowed the Bluetooth device to adjust the power level based on operational requirements (increasing based on the distance between devices).
Bluetooth 4.0, 4.1, and 4.2
Bluetooth 4.0 was one of the biggest improvements in Bluetooth technology. This version was released in 2010 and promoted more efficient energy consumption. As such, developers named Bluetooth 4.0 as Bluetooth “Smart.”
Aside from the lower energy consumption in Bluetooth Smart, it also increased its connectivity range, allowing devices to connect over longer distances without increasing power consumption.
Bluetooth 4.1 was released in 2013 and featured improvements in data transfer, compatibility, and non-interference with LTE signal frequencies. It also facilitated better connection among Bluetooth devices over physical barriers like walls without user intervention. It also had greater integration with the device’s power management plan.
The Bluetooth 4.2 update in 2014, moreover, increased data transfer speeds by up to 2.5x. It also increased security features in Bluetooth devices to prevent eavesdropping by requesting user permission for connecting and tracking. This allowed for beacon privacy which prevented retail shops from determining user location.
Bluetooth 5.0 was released in 2016 and is currently the latest version of Bluetooth. This Bluetooth version improved on various aspects such as energy consumption, range, speed, and capacity.
Bluetooth 5.0 adopts and improves the energy-saving features of Bluetooth 4.0 to extend the battery life of paired Bluetooth devices. It also increased the transmission range to 200 meters, which is 3-4x greater than the transmission range of Bluetooth 4.2. This allows greater outdoor usage for Bluetooth devices as well as uninterrupted use in confined spaces with physical barriers.
In terms of speed and capacity, Bluetooth 5.0 features twice the speed and eight times the capacity of Bluetooth 4.2. Data transfer speeds can depreciate at greater distances. Conversely, users can increase data transfer by keeping devices in short proximity. This works in preventing latency when streaming music into Bluetooth-capable wireless speakers.
One unique feature of Bluetooth 5.0 is its ability to connect to two wireless audio devices simultaneously. In the Samsung Galaxy S8, this feature is called Dual Audio. This allows the user to connect to two different wireless speakers in different areas. It can also be used to connect to two wireless speakers in the same room to create a stereo effect. Depending on the integration, however, some audio devices can exhibit slight latency when using dual audio.
Two of the first smartphones to use the Bluetooth 5.0 technology were the Samsung Galaxy S8 and the iPhone 8. However, there are still limited wireless devices that use Bluetooth 5.0. Still, devices with Bluetooth 5.0 can connect with devices with previous Bluetooth versions due to the backward compatibility of Bluetooth 5.0.
Bluetooth 4.0, specifically the 4.2 update, and Bluetooth 5.0 are the most common Bluetooth types used today. They provide sufficient data transfer speeds and range as well as improved security protocols and features.