BySteve Lowry 2018-06-08 9622
"Class" signifies the distance at which a Bluetooth connection is possible. Most mobile devices are Class 2, which means they have a range of up to 10 m. Class 1 devices are rare and have a range of up to 100 feet.
"Profile" is a type of Bluetooth connection. The most common are the Headset (HSP) and Handsfree (HFP) profiles that enable the device to connect to a wireless headset or handsfree.
Some other profiles are OBEX (OBject EXchange) which allows transfer of files, contacts and events; A2DP, which adds support for streaming of stereo sound and AVRC, which allows remote control of playback.
Bluetooth 1.0 and 1.0B: Bluetooth 1.0 and 1.0B had many problems and manufacturers had difficulty making their products interoperable. Versions 1.0 and 1.0B also included mandatory Bluetooth hardware device address (BD_ADDR) transmission in the connecting process (rendering anonymity impossible at the protocol level), which was a major setback for certain services planned for use in Bluetooth environments.
Bluetooth 1.1: It was ratified as IEEE Standard 802.15.1 in 2002. Bluetooth 1.1 is the earliest version with about 748 - 810 Kb/s transfer rate. Since it is early design, versions 1.1 tends to be disturbed by same-frequency products, thus influencing communication quality.
Bluetooth 1.2: This version is compatible with version 1.1, major enhancements include the following:
● Faster connection and discovery.
● Anonymous method: Shield Bluetooth hardware device address (BD_ADDR) to protect the users from identity sniffing attack and tracking. It has rendered hardware anonymity from version 1.1, but unfortunately, it is not carried out, so this function is useless for common clients.
● Adaptive frequency-hopping spread spectrum (AFH): It improves resistance to radio frequency interference by avoiding the use of crowded frequencies in the hopping sequence.
● Higher transmission speeds in practice, about 24Kb/s (192Kbps) in actual test.
● Introduce flow control and retransmission modes for L2CAP.
● Ratified as IEEE Standard 802.15.1 in 2005.
Bluetooth 2.0 + EDR: This version of Bluetooth core specification was released in 2004. The main difference is the introduction of an Enhanced Data Rate (EDR) for faster data transfer. The nominal rate of EDR is 3 Mbit/s, although the practical data transfer rate is 2.1 Mbit/s. EDR can provide a lower power consumption through a reduced duty cycle.
Bluetooth 2.1 + EDR: Bluetooth core specification version 2.1 + EDR was put forward by the Bluetooth SIG (Bluetooth Special Interest Group) on 26 July 2007.
The headline feature of Bluetooth 2.1 is secure simple pairing (SSP): this improves the pairing experience for Bluetooth devices, while increasing the use and strength of security.
Version 2.1 allows other improvements, including "Extended inquiry response" (EIR), which provides more information during the inquiry procedure to allow better filtering of devices before connection; and sniff subrating, which reduces the power consumption in low-power mode.
Bluetooth 3.0 + HS: Version 3.0 + HS of the Bluetooth core specification was put forward by the Bluetooth SIG on 21 April 2009. Bluetooth v3.0 + HS provides theoretical data transfer speeds of up to 24 Mbit/s, though not over the Bluetooth link itself. Instead, the Bluetooth link is used for negotiation and establishment, and the high data rate traffic is carried over a co-located 802.11 link.
The main new feature is AMP (Alternative MAC/PHY), the addition of 802.11 as a high speed transport. The High-Speed part of the specification is not mandatory, and hence only devices that display the "+HS" logo actually support Bluetooth over 802.11 high-speed data transfer. A Bluetooth 3.0 device without the "+HS" suffix is only required to support features introduced in core specification version 3.0 or earlier core specification.
Bluetooth 4.0: Bluetooth 4.0 is the latest Bluetooth version in 2012, and is an upgraded version of Bluetooth 3.0. Compared with Bluetooth 3.0, version 4.0 is more power saving, and have low cost, 3s low latency, long effective connection distance, AES-128 encryption, etc. It is usually used in Bluetooth headsets, Bluetooth speaker and other devices.
● Ultra-low peak, and power consumption in standby mode
● Standard cell batteries can run a year or even years
● low cost
● Interoperability of different vendor device
● Wireless coverage is enhanced
● Fully backward compatibility
● Low latency
Bluetooth 4.1: The Bluetooth SIG announced formal adoption of the Bluetooth 4.1 specification on 4 December 2013. This specification is an incremental software update to Bluetooth 4.0, and not a hardware update. The update incorporates Bluetooth Core Specification Addenda (CSA 1, 2, 3 & 4) and adds new features that improve consumer usability. These include increased co-existence support for LTE, bulk data exchange rates - and aid developer innovation by allowing devices to support multiple roles simultaneously.
New features of this specification include:
● Mobile wireless service coexistence signaling
● Train nudging and generalized interlaced scanning
● Low duty cycle directed advertising
● L2CAP connection oriented and dedicated channels with credit based flow control
● Dual mode and topology
● LE link layer topology
● 802.11n pal
● Audio architecture updates for wide band speech
● Fast data advertising interval
● Limited discovery time
Bluetooth 4.2: Bluetooth 4.2 was released on December 2, 2014. It Introduces some key features for IoT. Some features, such as Data Length Extension, require a hardware update. But some older Bluetooth hardware may receive some Bluetooth 4.2 features, such as privacy updates via firmware.
The major areas of improvement are:
● LE Data Packet Length Extension
● LE Secure Connections
● Link Layer Privacy
● Link Layer Extended Scanner Filter Policies
IP connectivity for Bluetooth Smart devices to become available soon after the introduction of Bluetooth 4.2 via the new Internet Protocol Support Profile (IPSP).
IPSP adds an IPv6 connection option for Bluetooth Smart, to support connected home and other IoT implementations.
Bluetooth 5.0: The Bluetooth SIG officially unveiled Bluetooth 5 during a media event in London on 16 June 2016.
● Faster transmission speed
According to Bluetooth 5.0 developers, the transmission speed of version 5.0 can reach up to 2Mbps, double than the previous version 4.2.
● Further effective range
Another major improvement of version 5.0 is that it quadruple the range. Theoretically, the effective range between Bluetooth transmitting and receiving device is 300 meters.
The navigation function enables the devices to serve as an indoor navigation beacon or similar positioning device. Combined with WiFi, you can get precise indoor positioning with accuracy less than 1 meter. Even if you are a road nerd, you can find your way in a large commercial center with the aid of Bluetooth 5.0 technology.
● Web of Things
Web of Things is still a hit, so Bluetooth 5.0 optimizes it in an effort to serve for smart home with less power consumption and stronger performance.
● Hardware upgrade
Precious Bluetooth version update requires only software upgrade, but Bluetooth 5.0 is likely to require upgrades to the new chip. However, the older hardware can still be compatible with Bluetooth 5.0, but you can not enjoy its new performance. Flagship phones equipped with Bluetooth 5.0 chip will come out in 2017, those low-end mobile phones will also follow to have built-in Bluetooth 5 chip.
● More data transferring capabilities
The Bluetooth 5.0 adds more data transfer capabilities. Hardware manufacturers can create a more complex connection system via Bluetooth 5.0, such as Beacon or location services. Therefore, the advertisement data transmitted via the Bluetooth device can send a small amount of information to the target device, even without pairing.
● Lower power consumption
Bluetooth 5.0 will greatly reduce the power consumption of Bluetooth, so that we will no longer have to worry about the short standby time when using Bluetooth.
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