Hardly any technology was foretold more often than Bluetooth. At the same time, it is impossible not to recognize the idea wireless quite successful: Bluetooth 1.0 hit the market more than 15 years ago, and never before has Bluetooth been used in as many devices as it is today. All thanks to the version Bluetooth 4.0, which now, however, seems to be rather slow.
Upgrade to 4.1
One billion Bluetooth devices are sold every year. But there are still few gadgets with Bluetooth 4.1. Currently announced smart bracelet Huawei TalkBand B1. Many modern chipsets, such as the OnePlus smartphone, will also be upgraded to 4.1.
Comes to replace Bluetooth Low Energy(or Bluetooth Smart) - version that saves battery power. In this case, the range of action is limited to 10 m, and the data transfer rate is 1 Mbit / s, but no more than 10 mA is consumed during transmission.
And now comes the next stage: the Bluetooth Special Interest Group, which includes more than 8000 companies, is preparing the version specification. Of course, no revolutionary changes should be expected, but some important innovations are expected for mobile users. CHIP decided to find out some technical issues.
Most of the innovations in Bluetooth 4.1 are related to anti-interference. Bluetooth is now standard on smartphones and tablets; LTE modules will soon be introduced into these devices.
Unfortunately, Bluetooth uses the unlicensed 2.45 GHz frequency band (along with 2.6 GHz), as well as the LTE band in Russia and other countries. This can lead to mutual interference (see diagram). The problem is that the user cannot influence the LTE signal in any way.
The developers of Bluetooth were required to take some action to avoid interference. And that is exactly what was done in the new version.
To minimize interference, Bluetooth 4.1 will have a built-in LTE band filter. If the LTE transmitter interferes with the data transmitted via Bluetooth, Bluetooth 4.1 will immediately react to this.
The sending and receiving of data by the LTE module interferes with the operation of Bluetooth. In version 4.0, losses reached 75% of packets. Bluetooth version 4.1 is not as susceptible to LTE interference. The noise filter protects the radio module. In difficult cases, the channel is automatically switched. The so-called adaptive switching system Bluetooth 4.1 will look for a different channel with less interference, transmitting and receiving data on a different frequency. While for Bluetooth 4.0 LTE interferes 75% of the time, with Bluetooth 4.1 this figure drops to 25%.
Receive and transmit data without interference
Devices with Bluetooth Low Energy are especially popular now. Specifically for this power saving mode, version 4.1 has a new data transfer method that extends battery life.
Learned from bitter experience, Bluetooth users are aware of the problem of disconnected connections. It often happened that if the user went to another room, the connection was interrupted. After that, you had to configure the connection manually.
Fewer disconnections with new Bluetooth
If two Bluetooth devices go out of range, the connection will be terminated. With Bluetooth 4.0 for automatic connection, the devices must return to the range within 30 seconds. In version 4.1, this time is increased to three minutes.
With Bluetooth 4.1, manufacturers can set fixed intervals so that the user does not have to set up a new connection every time after disconnecting. Bluetooth 4.1 can work with an interrupted connection for up to three minutes - earlier this figure was no more than 30 seconds.
The fact that you do not need to connect to a computer to use Bluetooth is demonstrated by an innovation developed specifically for 3D glasses that work in conjunction with a TV. As a rule, this required connecting to several devices at once, so the image on TVs often lagged behind. Everything should work better now.
Contactless Slave Broadcast in Bluetooth 4.1 is the second new function which fans of 3D cinema will benefit from. The Bluetooth connection is only in one direction, the TV sends data at fixed intervals, the 3D glasses receive data, but do not send any return connections to the TV.
Flexible Connections with Bluetooth 4.1
The Bluetooth 4.1 connectivity architecture functions according to the master-slave principle. In this case, one device acts as a master (Master), and the second as a slave (Slave). All devices can operate both as masters and slaves.
Thus, the data of a fitness bracelet or heart rate monitor can now be transmitted directly to a smartphone, which will then analyze it. Previously direct interaction fitness bracelet and smartphone was impossible.
Two advantages of bluetooth upgrade: first, no need to worry about compatibility. Bluetooth 4.0 and Bluetooth 4.1 are absolutely compatible. A new chip for Bluetooth 4.1 is also not needed. Bluetooth 4.1 will be available via Bluetooth 4.0 firmware update.
Experts also predict that Bluetooth 4.1 will support IPv6. Now this is not the case. Since the new version of Bluetooth fully supports IPv6, all Bluetooth devices will be assigned an IP address and can be accessed over the Internet. So we can say that the Bluetooth revolution has already begun.
Bluetooth in comparison
Bluetooth has been around for 15 years, and new versions are released every two years. Version 4.0 introduces a low power profile. Since its predecessors do not have it, the 4.0 and 4.1 protocols are not backward compatible. In 4.1, it is planned to work on the IPv6 protocol.
| Bluetooth 4.0 | Bluetooth 3.0 | Bluetooth 2.x | Bluetooth 1.x | ||
|---|---|---|---|---|---|
| Base speed | 1 Mbps | 1 Mbps | 1 Mbps | 1 Mbps | 1 Mbps |
| Enhanced Data Rate (EDR) | 3 Mbps | 3 Mbps | 3 Mbps | 3 Mbps | No |
| High speed | 54 Mbps | 54 Mbps | 54 Mbps | No | No |
| Range (max / min power) | 100 m / 10 m | 100 m / 10 m | 100 m / no | 100 m / no | 100 m / no |
| Low power mode | Yes | Yes | No | No | No |
| Dual profile (simultaneous role as Slave and Master) | Yes | No | No | No | No |
| IPv6 support | preparing | No | No | No | No |
| Pairing with NFC | Yes | Yes | Yes | Yes | No |
| 128-bit AES encryption | Yes | Yes | No | No | No |
Photos in the article: manufacturing companies
Short-distance data transmission technology dates back to 1994, when two engineers at Ericsson decided to permanently do away with wires when exchanging data between mobile devices. This technology is called Bluetooth("Blue Tooth"). The technology got its name from Harold the First Bluetooth, who was the king of Denmark and Norway, who became famous for uniting the Scandinavian tribes under his rule in the 10th century.
Communication standard description
Initially, the development was carried out at frequencies that are not subject to additional licensing. These are 79 channels operating at frequencies from 2402 MHz to 2480 MHz, which are specially allocated for the operation of medical and scientific equipment.
The exchange of information between the receiver and the transmitters is carried out by constantly changing channels approximately 1600 times per second. Only the receiving and transmitting device knows which channel the switching will take place; notification occurs by means of special identification keys. This method minimizes the possibility of interference and allows the paired devices to not conflict with each other. Bluetooth standard is one of the most secure ways to exchange information, because it is impossible to connect to a device without permission. The only problem with this type of communication is the very small range, but on the other hand it also increases the level of security.
According to the power of radio transmitters, the standard is divided into three large groups or classes:
- Class 1 is used mainly in medical equipment, which is sufficient for a transmitter with very low power.
- Class 2 with medium power transmitters can be seen in modern mobile phones, tablets and other peripherals.
- Class 3 uses very powerful transmitters and finds its application in industrial plants, for example, to control individual machine tools or the entire production process as a whole.
Connection is possible not only between two devices. The number of simultaneously connected devices is limited to 71 devices, with one device acting as a master or master device, and all the others acting as masters (slave). A device that works as a slave, in turn, can act as a master for those connected to it. This way you can create a whole network called a piconet. More than ten piconets cannot be connected at the same time.
Evolution of the standard
Since the introduction of the standard in 94, the standard has been called Bluethooth 1.0. It was still a very crude product. It had a lot of security vulnerabilities due to the fact that it was necessary to transmit the device address in clear text. There were also difficulties with pairing devices from different manufacturers. Bluetooth speed also left a lot to be desired. In version 1.1, it became possible to see the signal level and support for non-encrypted channels was added.
Research continued constantly, but the next bluetooth version 2.0 appeared only in 2007. Has been significantly increased bluetooth speed, which reached almost 2.5 MB / s, and in version 2.1, the power consumption parameters were significantly redesigned and reduced. Improved security and speed of device pairing.
In April 2007 was presented bluetooth standard 3.0. Together with the use of asynchronous multiprocessing technology, the data exchange rate was 24 Mb / s, but power consumption increased. The increase in power consumption haunted the developers, because for mobile devices this is a rather critical moment. After revisions at the end of the year, the wider public was able to see bluetooth 4 which is still used today.
The main difference from previous versions is the very low battery consumption. This is also achieved by the fact that the signal is not transmitted constantly, but only as needed, i.e. the transmitter is in constant standby mode, and turns on only when necessary.
The connection between devices now takes place in 5 ms, and the distance between devices can now reach 100 meters in line of sight. The degree of data encryption in bluetooth 4 occurs according to a 128-bit algorithm. This standard has become the reference for connecting peripheral devices such as headphones, external speakers, smart watches and many others.
In different versions bluetooth baud rate next:
- 2 - up to 1 Mb / s;
- 0 - up to 3 Mb / s;
- 0 and v4.0 - up to 24 Mb / s.
Manufacturers try to design devices in such a way that they support various bluetooth versions, for greater compatibility between devices.
The use of bluetooth in everyday life
Nowadays, information transfer using bluetooth is quite popular, and interest in the technology is constantly growing. There are many areas of activity where it has found its application:
- data exchange between two mobile phones;
- download photos from a digital camera without using a wired connection;
- connecting a mouse, keyboard, printer, scanner and other peripherals to a computer or laptop;
- data synchronization between PC and mobile device;
- connecting a headset, smart watch and other devices to a mobile phone.
The imagination of developers about where to use Bluetooth is limitless. New and new products are constantly being supplied to the market that support the work on this technology.
An interesting word called Bluetooth is a protocol for exchanging information over short distances. Its coverage area is rather modest compared to Wi-Fi (maximum 100 meters, and then at best if you have latest version), and the data transfer rate is low. But these disadvantages are compensated by the low power consumption and high connection speed (so-called pairing) of the phones.
Bluetooth is a very old technology in the IT market; the first version (1.0) was born back in 1998. At the moment it is considered morally obsolete and is not used in any commercially available device.
Bluetooth versions
The next version of the protocol is 1.2 - now also considered outdated, but it has faithfully served phone users for much longer. It can still be found in some cheap mobile devices made in China. The maximum data rate of Bluetooth 1.2 is 721 Kbps. Phones pair much faster, you can be online anonymously. This version of the protocol allows you to transfer not only music and pictures, but also other types of files, as well as service data.
The emergence of EDR technology, or Enhanced Data Rate, was the next step in the development of Bluetooth, and quite a big one. The data transfer rate in theory increased to 3 Mbit / s, although in practice it usually did not rise above 2 Mbit / s. This technology is supported by two versions of bluetooth - 2.0, released in 2004, and 2.1, which was born in 2007. They are almost completely identical, differ only in energy saving technologies.
WITH Bluetooth 2.1 almost all commercially available are compatible mobile phones, navigators, headsets and other devices. Power consumption compared to previous versions protocol dropped by almost 10 times, which made possible the mass production of compact headsets.
Bluetooth version 3.0 appeared in 2009, and with its appearance became possible transfer information at a much higher speed than before (HS technology, or High Speed). Devices compatible with Bluetooth 3.0 + HS are equipped with 2.1 + EDR (up to 3 Mbps), as well as a second module that works in a similar way to Wi-Fi and provides speeds up to 24 Mbps. Despite the similar principle of operation, there is no direct compatibility with Wi-Fi.
HS technology, with all its advantages, had one serious drawback - high power consumption. However, already in 2010, when Bluetooth 4.0, it has been fixed. The chip of this version is present in all top smartphones and tablets, as well as in most ultrabooks. Data can be transferred at a distance of up to 100 meters at a speed of up to 30 Mbps.
It should be noted, however, that not all possibilities of this standard Bluetooth are required. So, the possibility of a long autonomous work(function Bluetooth Low Energy) is only supported by the latest devices.
Most peripherals such as headsets, navigators, etc. support Bluetooth 2.1 + EDR, so if your device supports the same version, you should be fine. Although some devices may support other versions of the protocol. For example, the Texas Instruments MetaWatch debug clock, which displays various information about a smartphone on the display, supports Bluetooth 4.0. For this to work, your machine must support the same version.
If high-speed information transfer is important for you, then you need Bluetooth version 3.0 or 4.0 on both devices. Though high speed data transfer can be achieved through NFC technology (S Beam function in new Samsung smartphones). Yes, and Wi-Fi Direct in many cases is more expedient to use, because this function is supported by many devices based on Android 4.0 OS, and the transmission speed is much higher compared to Bluetooth.
Bluetooth profiles
Dealt with the Bluetooth versions; each has its own characteristics - you can't confuse it. And also do not confuse bluetooth versions with profiles. A profile is a specific activity that is possible on different versions of the protocol.
Profile A2DP provides the ability to transfer files and stereo sound, which is available in Bluetooth version 1.2 and higher. However, each specific device may have its own set of profiles, so that some actions, even taking into account the latest version of bluetooth, may not be available. For example, Windows-based smartphones do not support the exchange of information via Bluetooth, and the user will have to resort to some tricks if he wants to use this protocol feature.
Come in and remember how it all began.
How do you personally feel about wires? Let's outline a very extraordinary and even somewhat amusing situation.
Apple Watch connects to a smartphone via the Lightning port (they do not work without it); the athlete has no choice in what to listen to music - only wires, only hardcore; all "smart" appliances in the house only work when a smartphone is connected "by a cord" ...
Not a very bright prospect, is it?
Scary dream of a gadget lover
And all this could be reality today, if 20 years ago large corporations did not think about creating a unified technology wireless transmission data with a small range - Bluetooth.
It's time to unite
A number of manufacturers such as Ericsson, Nokia, Intel, Toshiba and dozens of others have thought about creating a single standard for wireless data transmission. By combining efforts and gathering all the engineering potential into a single group, on May 20, 1998, the above companies officially entered the so-called SIG - Special Interest Group.
The goal of this “common interest group” was to introduce wireless data transmission technology Bluetooth... And most importantly, the new technology was supposed to become unified, putting an end to confusion and device compatibility when wireless pairing was required.
Dell, Xircom, Motorola, Compaq, Qualcomm - all of these brands are soon to be part of the SIG.
And today the SIG membership includes more than 30,000 companies from all over the world. Bluetooth has long been taken for granted and the number of devices in which this wireless protocol is integrated is beyond counting.
Meanwhile, the estimated number of Bluetooth-enabled devices is around 8.2 billion.
First went: Bluetooth 1.0-1.2
In 98, many businessmen dreamed about it.
The firstborn of the wireless protocol was Bluetooth 1.0, announced in 1998. The first version obviously could not do without flaws and errors.
Key issues include highly unstable signal and constant interruption of the connection. Moreover, manufacturers began to note the lack of proper device compatibility. For example, two different companies that launched two compatible devices on the market could not be sure that the user would be able to connect them via Bluetooth.
They immediately rushed to save the situation and a year later presented the updated Bluetooth 1.0B. It got better, but the ideal was still far away. Bluetooth 1.0 (B) required the obligatory transmission of the device address, which means there was no point in talking about any anonymity. This was the main disadvantage of the protocol at the inception stage. In 2000, the presentation of the updated Bluetooth 1.1 took place. Users could now determine the signal strength wireless connection and transfer data over unencrypted channels.
Legendary Bluetooth 1.2 compatible headset from Motorola
The first global update was Bluetooth 1.2, which received a number of improvements at once: from increasing the data transfer rate (up to 1 Mbps) and improving noise immunity to supporting the A2DP profile, which for the first time allowed the transmission of stereo sound.
Time to Grow Up: Bluetooth 2.0 - 2.1 (EDR)
An amateur developer's dream - Bluetooth 2.0 module for Arduino
In 2004, manufacturers waited for Bluetooth 2.0. Among the innovations of this version:
- Increased data transfer rate. According to the documentation, Bluetooth 2.0 had a bandwidth of 3 Mb / s, but practice is a merciless thing. The maximum that could be squeezed out of Bluetooth 2.0 was 2.1 Mb / s.
- The emergence of EDR technology, which testified to a more advanced version of the protocol, directly affecting the speed.
- Additional bandwidth for synchronous connection of multiple devices.
- Slight reduction in energy consumption.
The next update dates back to 2007. For three years, engineers have been working on the possibility of reducing the gluttony of the protocol in relation to the battery. portable devices and together with Bluetooth 2.1 announced new technology Sniff Subrating. The energy efficiency of the new "blue tooth" has increased up to 10 times, and the pairing of devices has become much easier.
In the same year, NFC (Near Field Communication) technology was released, which is responsible for proper connection protection.
Almost Wi-Fi: Bluetooth 3.0 + HS
These are the Link Dream smart watches in 2009
On April 21, 2009, the new Bluetooth 3.0 standard was adopted. This time, the engineers set themselves the goal of significantly increasing the data transfer rate. In theory, the figure turned out to be 24 Mbit / s.
Bluetooth 3.0 included two versions of the radio system: standard 2.0 (up to 3 MB / s) and compatible with 802.11, high speed (up to 24 MB / s).
Depending on the size of the transmitted file, the version of the radio system also changes. Despite using the 802.11 standard, Bluetooth 3.0 is incompatible with any Wi-Fi specification.
Dieter: Bluetooth 4.0 - 4.2
iPhone 4s became the first smartphone to receive support for Bluetooth 4.0
The third version of Bluetooth lasted only a year. A number of manufacturers did not have time to thoroughly "hook" on the new standard, as on June 30, 2010 SIG approves Bluetooth 4.0 - a new word in the life of wireless technology.
The main focus of the technology is extremely low power consumption. The developers relied on the integration of Bluetooth 4.0 into miniature gadgets, sensors, sensors and other devices in which it is impossible to place a capacious battery.
As a result, Bluetooth 4.0 worked in a completely different way. Instead of constant activity, it turns on only at the moment of sending or receiving data, significantly saving the battery power of the device.
For example, a miniature sensor can operate on a CR2032 battery for several years:
The range has been increased to 100 meters, the data transfer rate, for the sake of energy efficiency, has been reduced to 1 Mbit / s.
Over the next four years, Bluetooth 4.0 received two more updates: 4.1 - with an emphasis on compatibility with LTE networks and 4.2 - with increased throughput (2.5 times) and improved security.
Bluetooth 5.0
The history of the development of the protocol continues to be created right before our eyes. On June 17, 2016 SIG announced a new specification.
It will take a little time to appreciate the updated technology. The first devices with Bluetooth 5.0 will not appear until the end of this early next year, but today the developers have promised:
- 4 times faster data transfer rate compared to version 4.2
- two-fold increase in signal range
- reduced power consumption compared to Wi-Fi modules
But the most interesting thing is that Bluetooth 5.0 received the "Smart" prefix, which means that the "intelligence" of mobile gadgets will become even more advanced. The bright future is just beginning!
Wireless bluetooth headsets is a category of precisely those devices that have been the engine of technology development for 18 years. Headsets have evolved from low-quality rattling sound with minimal battery life to stylish fashion accessories that are a pleasure to talk to.
Our picks in the Bluetooth headset segment:
- Excellent and crystal sound with Plantronics Explorer 500
- Unique design and superior voice quality
Any sound starts from the source. Today, there are many wireless protocols for transmitting sound. Some of them are much more interesting than Bluetooth, but have not yet received proper distribution. Today almost all smartphones, laptops and tablets are equipped with Bluetooth, and it takes five minutes to equip a device with its support if there is a USB output.
Therefore, today we will restrict ourselves to sound-reproducing devices using the "blue tooth" (the guide is quite suitable for choosing a Bluetooth speaker). This technology has a rather long history and a lot of pitfalls, the existence of which users do not always know.
The presence of a Bluetooth transmitter does not mean that the device can be used as a sound source for wireless audio equipment. Not every Bluetooth will allow you to listen to high-quality music without distortion. Not everyone is suitable for listening to files with high bitrate and lossless formats.
What to look for in order to listen to music wirelessly - whether it's just an MP3 or a high-quality rip from a vinyl record, we will tell in this article.
Let's start with the most important thing: this parameter directly says whether it is possible to listen to music using the device.
VersionBluetooth
V modern devices most often you can find support for Bluetooth 3.0 or 4.0, in some top smartphones and other gadgets - 4.1. In this case, it may well turn out that the purchased headset only supports connection using protocol version 2.1. The adapters are backward compatible, but the slowest protocol of the two works when connected.
The difference between the versions of the protocol for regular user are minimal due to backward compatibility. The main thing that catches your eye is with each new version power consumption of devices is reduced, and starting with 3.0 a second module has been added for high-speed data transfer at a speed of 24 Mbps.
Version 2.1 + EDR transfers data at a rate of no more than 2.1 Mbps. This is enough to play a low bitrate audio stream. It is recommended to use Bluetooth version 3.0 or higher for audio and video streaming.
It should be noted that for the full use of the device as a player, it is highly desirable to have Bluetooth version 4.0 and higher, or better - with reduced power consumption.
This adapter can be identified by the following categories.
ProfilesBluetooth
Profiles are a collection of specific functions supported by devices. Of all those used in Bluetooth for listening to music, the following are interesting:
- Headset Profile (HSP) It is necessary for communication of the headset and smartphone and wireless transmission of mono sound with a bitrate of 64 kbps.
- Hands-Free Profile (HFP) also provides only mono transmission, but with higher quality.
- Advanced Audio Distribution Profile (A2DP) required for two-channel audio streaming.
- Audio / Video Remote control Profile (AVRCP) provides control over the functions of playback devices (without it, even changing the volume of music is impossible).
A2DP is required for full listening to music. It not only handles the transmission of the audio stream, but also controls the compression of the data before transmission.
However, even if both the transmitting and playing device (such as a smartphone and wireless headphones) are equipped with Bluetooth 3.0 or 4.0 and support work with the required protocol, you need to pay attention to the codec that is used.
CodecsBluetooth
The most important thing for playing music using the A2DP protocol is the codec that compresses the audio stream transmitted to the headset. There are currently three codecs in total:
- Subband Coding (SBC)- the codec used by A2DP by default and created by the profile developers. Unfortunately, the SBC has a much rougher pressure than MP3. And therefore, it is not suitable for listening to music.
- Advanced Audio Coding (AAC)- a more advanced codec that uses different compression algorithms. Sounds much better than SBC.
- Aptx- here it is, right choice! At least because of the ability to transfer files to MP3 and AAC without additional manipulation and transcoding. This means, and without degradation of sound. However, it is worth making a reservation. There are several versions of aptX to play different bitrates. Each of them is intended for its own sound stream.
| Version | Number of channels supported | Maximum sampling rate, kHz | Quantization, bit | Max bitrate | Compression ratio |
| Aptx | 2 | 44,1 | 16 | 320 kbps | 2:1 |
| Enhanced AptX | 2, 4, 5.1, 5.1+2 | 48 | 16, 20, 24 | up to 1.28 Mbps | 4:1 |
| Aptx live | n / a | 48 | 16, 20, 24 | n / a | 8:1 |
| Aptx lossless | n / a | 96 | 16, 20, 24 | n / a | n / a |
| AptX Low Latency | n / a | 48 | 16, 20, 24 | n / a | n / a |
»
The main features of the last two versions of the codec are the lowest possible latency of audio playback and reduced load on the processor during encoding. The Low Latency version achieves 32ms latency between the audio stream source and the playback device. This will reduce the distortion introduced by the equipment when listening to music.
Thus, with certain preferences, you can choose a certain codec. If the playback of a lossless stream is not expected, and high audio latency is not critical, you should limit yourself to standard aptX and do not overpay for device support for subsequent versions.
It is worth remembering that the required profile and codec must be supported both by a smartphone (or other audio stream source) and by the headset itself (or a Bluetooth speaker). Otherwise, the A2DP algorithm will automatically start using SBC.
Any two devices with Bluetooth always work using the lowest version, the simplest codec and protocol. So what if one of them has no support necessary technology, you will not be able to fully enjoy the sound quality.
Long-term listening to music requires Bluetooth 3.0 or higher, aptX codec and A2DP profile. To listen to high bitrate music, you need to support the aptX Lossless codec - neither will work, as the music will be compressed when transferred to the playback device.
