Translated from Danish into English, Bluetooth means “blue-toothed”. This was the name of the Danish king Harold I for his peculiarity - a dark front tooth. This king also became famous for being able to unite several warring Danish tribes. Bluetooth also has the ability to unite, not tribes, but communication protocols into one universal standard. The development of Bluetooth technology belongs to the Ericsson company; to implement this idea, in 1999 an association of well-known world brands Toshiba, Sony, IBM, Intel, Nokia and many others was created under one name SIG (Bluetooth Special Interest Group).
Using radio waves in the ISM range (2.4-2.48 GHz - a range not subject to licensing) Bluetooth designed to provide wireless communication between devices such as: cell phones, printers, computers, digital cameras, headphones, cameras and so on. The transmit signal is called Frequency Hopping Spread Spectrum (FHSS) and is a broadband signal. In Bluetooth, using the frequency hopping method, the frequency of the FHSS carrier signal changes abruptly 1600 times per second, 79 operating frequencies are used for this purpose. For each connection, the frequency changes in a pseudo-random manner.
According to these changes, every 625 μs they synchronously move from one frequency to another. This sequence of changes connects several receiver-transmitter pairs without blocking the operation of other connection pairs. The peculiarity of signal transmission is that the transmitted information remains confidential. Digital data and audio signals are encoded differently: the audio signal is usually not repeated, and digital data is retransmitted if lost. With the help of such signals, devices can transmit information to each other at a distance of 10 - 100 meters, even when located in different rooms.
For many people, such devices seem complicated and unnecessary. We are accustomed to a more familiar connection using a cable. It is Bluetooth technology that opens up information communications for us in a completely new way. various devices. Bluetooth devices are essential in modern life and are used for work, leisure and entertainment. Bluetooth devices include headsets, car kits, speakers and others. One of the most popular devices is Bluetooth headset, designed for speakerphone. Bluetooth for phones also allows you to talk on the phone without holding it in your hands.
Usually we take Bluetooth for a laptop for granted, but whether the Bluetooth function is installed or the Bluetooth settings for the computer are lost - this can be easily checked through the “device manager”, Bluetooth will be listed in the network adapters, but if it is not there - download bluetooth and installing it will not be particularly difficult. Bluetooth equipment is characterized by reliability, resistance to broadband interference, cost-effectiveness, and low power and energy consumption.
Most Bluetooth devices have a separate USB interface and an internal antenna. Such devices can interact with both personal computers and laptops. They are considered universal, but there is also a category of devices that are intended for installation inside computers. They are made in the form of boards located in the slots of computer motherboards (reminiscent of USB flash drives). Thanks to the sensitivity of the external antenna, the range of Bluetooth devices can be extended up to 200 meters.
Many people believe that Wi-Fi and Bluetooth are the same thing, but this is a deep misconception. Bluetooth was created to transfer data between two devices with a range of up to 100 meters, it works according to its standards Bluetooth 1.0 and Bluetooth 2.0 and others, it is also very easy to use, using Bluetooth you can only create a personal network PAN. WiFi- this is also a wireless communication standard, the range of which can reach 300 meters, Wi-Fi operates in accordance with 802.11 b/g/n/ standards with the mandatory use of an adapter (router) for communication, creates wireless local network WLAN, which can involve several different devices.
The presence of Bluetooth technology allows for interactive conferences, Internet bridges, automatic data synchronization between different digital devices, allows you to enjoy a cable-free desktop, and also solves various network problems at home and in the office. Bluetooth in a laptop will please its owner when traveling or on business trips. To buy Bluetooth, you should definitely consult with the seller and clarify specific features this type of technology.
Bluetooth technology is effectively spreading in the global market for the latest technologies. Bluetooth headsets for mobile phones, laptops, printers, keyboards, and mice are being actively produced. The Bluetooth standard development company is focused on improving Bluetooth wireless communications and bringing new Bluetooth profiles to life.
Bluetooth ensures the exchange of information between devices such as personal computers (desktop, pocket, laptops), mobile phones, printers, digital cameras, mice, keyboards, joysticks, headphones, headsets on a reliable, free, universally available radio frequency for short-range communication.
Bluetooth allows these devices to communicate when they are within a radius of up to 100 meters from each other (range varies greatly depending on obstacles and interference), even in different rooms.
Name and logo
The word Bluetooth is the English translation of the Danish word "Blåtand" ("Blue-toothed"). This nickname was worn by King Harald I, who ruled Denmark and part of Norway in the 10th century and united the warring Danish tribes into a single kingdom. The implication is that Bluetooth does the same with communication protocols, combining them into one universal standard. Although "blå" means "blue" in modern Scandinavian languages, in Viking times it could also mean "black in color." Thus, historically it would be correct to translate the Danish Harald Blåtand as Harald Blacktooth rather than Harald Bluetooth.
Bluetooth logo is a combination of two Nordic (“Scandinavian”) runes: “Hagall” - an analogue of the Latin H and “Berkanan” - the Latin B. The logo is similar to the older logo for Beauknit Textiles, a division of the Beauknit Corporation. It uses a fusion of reflected K and B for "Beauknit" and is wider and has rounded corners, but is basically the same.
History of creation and development
Bluetooth Specification was developed by the Bluetooth Special Interest Group (Bluetooth SIG), which was founded in 1998. It included Ericsson, IBM, Intel, Toshiba and Nokia. Subsequently, the Bluetooth SIG and the IEEE reached an agreement whereby the Bluetooth specification became part of the IEEE 802.15.1 standard (published June 14, 2002). Ericsson Mobile Communication began work on creating Bluetooth in 1994. Initially, this technology was tailored to the needs of the FLYWAY system for a functional interface between travelers and the system.
How Bluetooth works
The operating principle is based on the use of radio waves. Bluetooth radio communication is carried out in the ISM band (Industry, Science and Medicine), which is used in various household appliances and wireless networks (licensing-free range 2.4-2.4835 GHz). Bluetooth uses Frequency Hopping Spread Spectrum (FHSS). The FHSS method is easy to implement, provides immunity to broadband interference, and the equipment is inexpensive.
According to the FHSS algorithm, in Bluetooth the carrier frequency of the signal changes abruptly 1600 times per second (in total, 79 operating frequencies with a width of 1 MHz are allocated, and in Japan, France and Spain the band already has 23 frequency channels). The sequence of switching between frequencies for each connection is pseudo-random and is known only to the transmitter and receiver, which synchronously switch from one carrier frequency to another every 625 μs (one time slot). Thus, if several receiver-transmitter pairs operate nearby, they do not interfere with each other. This algorithm is also integral part systems for protecting the confidentiality of transmitted information: the transition occurs according to a pseudo-random algorithm and is determined separately for each connection. When transmitting digital data and audio signals (64 kbit/s in both directions), various schemes encoding: the audio signal is not repeated (as a rule), and digital data will be retransmitted if the information packet is lost.
Bluetooth 1.0
Device versions 1.0 (1998) and 1.0B had poor compatibility between products from different manufacturers. In 1.0 and 1.0B, it was mandatory to transmit the device address (BD_ADDR) at the handshake stage, which made it impossible to implement connection anonymity at the protocol level and was the main drawback of this specification.
Bluetooth 1.1
Bluetooth 1.1 fixed many bugs found in 1.0B, added support for unencrypted channels, and received signal strength indication (RSSI).
Bluetooth 1.2
Version 1.2 added adaptive frequency hopping (AFH) technology, which improves immunity to electromagnetic interference (interference) by using staggered frequencies in the tuning sequence. The transmission speed also increased and eSCO technology was added, which improved the quality of voice transmission by repeating damaged packets. HCI has added support for a three-wire UART interface.
Major improvements include the following:
Fast connection and discovery.
Adaptive frequency hopping with spread spectrum (AFH), which improves immunity to radio interference.
Higher data transfer rates than in 1.1, almost up to 721 kbit/s.
Enhanced Synchronous Coupling (eSCO), which improves the voice quality of an audio stream by allowing damaged packets to be retransmitted, and can optionally increase audio latency to better support parallel data transfers.
Support for a three-wire UART interface has been added to the Host Controller Interface (HCI).
Approved as IEEE Standard 802.15.1-2005.
Flow Control and Retransmission Modes have been introduced for L2CAP.
Bluetooth 2.0+EDR
Bluetooth version 2.0 was released on November 10, 2004. It is backward compatible with previous versions 1.x. The main innovation is support for Enhanced Data Rate (EDR) to speed up data transfer. The nominal speed of EDR is about 3 Mbit/s, but in practice this allowed increasing the data transfer rate only to 2.1 Mbit/s. Additional performance is achieved using various radio technologies for data transmission.
The standard (base) data rate uses GFSK modulation of the radio signal at a transmission rate of 1 Mbit/s. EDR uses a combination of GFSK and PSK modulations with two options, π/4-DQPSK and 8DPSK. They have high data transfer rates over the air - 2 and 3 Mbit/s, respectively.
The Bluetooth SIG has published the specification as "Bluetooth 2.0 + EDR Technology", which implies that EDR is an optional feature. In addition to EDR, there are other minor improvements to the 2.0 specification, and products may comply with "Bluetooth 2.0 Technology" without supporting higher data rates. At least one commercial device, the HTC TyTN Pocket PC, uses "Bluetooth 2.0 without EDR" in its technical specifications.
According to the 2.0+EDR specification, EDR provides the following benefits:
Increase the transfer speed by 3 times (2.1 Mbps) in some cases.
Reduced complexity of multiple simultaneous connections due to additional bandwidth.
Lower energy consumption due to load reduction.
Bluetooth 2.1
2007 Added technology for advanced request for device characteristics (for additional filtering of the list when pairing), energy-saving technology Sniff Subrating, which allows you to increase the operating time of the device on a single battery charge by 3-10 times. In addition, the updated specification significantly simplifies and speeds up the establishment of communication between two devices, allows updating the encryption key without breaking the connection, and also makes these connections more secure thanks to the use of Near Field Communication technology.
Bluetooth 2.1+EDR
In August 2008, Bluetooth SIG introduced version 2.1+EDR. The new Bluetooth edition reduces energy consumption by 5 times, increases the level of data security and makes it easier to recognize and connect Bluetooth devices by reducing the number of steps it takes.
Bluetooth 3.0+HS
3.0+HS was adopted by the Bluetooth SIG on April 21, 2009. It supports theoretical data transfer rates of up to 24 Mbps. Its main feature is the addition of AMP (Asymmetric Multiprocessing) (alternatively MAC/PHY), an addition to 802.11 as a high-speed message. Two technologies were provided for AMP: 802.11 and UWB, but UWB is not in the specification.
Modules supporting the new specification combine two radio systems: the first provides data transmission at 3 Mbit/s (standard for Bluetooth 2.0) and has low power consumption; the second is compatible with the 802.11 standard and provides the ability to transfer data at speeds of up to 24 Mbit/s (comparable to the speed of Wi-Fi networks). The choice of radio system for data transmission depends on the size of the transmitted file. Small files are transferred over a slow channel, while large files are transferred over a high-speed channel. Bluetooth 3.0 uses the more generic 802.11 standard (without a suffix), meaning it is not compatible with Wi-Fi specifications such as 802.11b/g or 802.11n.
Bluetooth 4.0
The Bluetooth SIG approved the Bluetooth 4.0 specification on June 30, 2010. Bluetooth 4.0 includes Classic Bluetooth, High Speed Bluetooth, and Bluetooth Low Energy protocols. High Speed Bluetooth is based on Wi-Fi, while Classic Bluetooth consists of protocols from previous Bluetooth specifications.
The Bluetooth Low Energy protocol is intended primarily for small devices. electronic sensors(used in sports shoes, exercise equipment, miniature sensors placed on the body of patients, etc.). Low power consumption is achieved through the use of a special operating algorithm. The transmitter is turned on only while sending data, which makes it possible to operate on a single CR2032 battery for several years. The standard provides a data transfer rate of 1 Mbit/s with a data packet size of 8-27 bytes. Two Bluetooth devices will be able to establish a connection in less than 5 milliseconds and maintain it at a distance of up to 100 m. Advanced error correction is used for this, and the necessary level of security is provided by 128-bit AES encryption.
Sensors for temperature, pressure, humidity, speed of movement, etc. based on this standard can transmit information to various control devices: mobile phones, PDAs, PCs, etc.
The first chip supporting Bluetooth 3.0 and Bluetooth 4.0 was released by ST-Ericsson at the end of 2009.
Bluetooth 4.0 is supported on MacBook Air and Mac mini (since July 2011), iMac (November 2012), iPhone 4S (October 2011) and iPhone 5 (September 2012), iPad 3 (March 2012), LG Optimus smartphones 4X HD (February 2012), HTC One X, S, V and Samsung Galaxy S III (May 2012), Explay Infinity (August 2012), HTC One X+ (2012), HTC Desire C, Google Nexus 7 (2012), Sony VAIO SVE1511N1RSI.
Hello everyone, dear users of the best mobile portal Trashbox. Today is September 1, the official day of knowledge, and in the meantime I continue my interesting column “How it works.” Before I start, I would like to congratulate all the students on their day - good luck in your studies and don’t dare miss out - you will regret it. Today I want to talk about Bluetooth, one of the most popular wireless interfaces. Let's find out what Bluetooth is and how it works. The most interesting under the cut.
Bluetooth (translated as “blue tooth” or popularly “blue tooth”) is one of the wireless network technologies that ensure the exchange of information between various devices, including personal computers, laptops, mobile phones, printers, cameras and other similar products. Bluetooth allows devices to communicate - the maximum range is 100 meters from each other.
The main objective of Bluetooth technology is to transfer data between devices wirelessly - providing economical and cheap radio communication between various types of electronic devices.
The operating principle is based on the use of radio waves, and Bluetooth technology itself is a small chip that is a high-frequency transceiver. It operates in the ISM (Industry, Science and Medicine) band, as these frequencies do not require a license to use - they are free for use worldwide (exceptions: France and Spain).
The fundamental principle of building Bluetooth-based networks is the Frequency Hopping Spread Spectrum (FHSS) method. The FHSS method is easy to implement - it provides immunity to broadband interference, and the equipment is inexpensive.
The transmitter breaks the data into packets and transmits them using a pseudo-random algorithm, in which the carrier frequency (pattern) changes 1600 times per second and takes the value of one of 79 subfrequencies. The sequence of switching between frequencies for each connection is pseudo-random and is known only to the transmitter and receiver.
Several devices connected using Bluetooth form a so-called piconet - a collection of two to eight devices operating on the same template. In a piconet, one of the devices is the master and the other is the slave. Bluetooth technology can support several slave devices - up to a maximum of seven. The master is the user device that initiates the communication. It also controls the operation of devices in the piconet.
Bluetooth allows the transmission of both voice and data. Voice is transmitted over three audio channels at a speed of 64 Kbps each. Data transfer rates are approximately 720 Kbps in asymmetric and 420 Kbps in fully symmetrical or full duplex (two-way) mode. The “blue tooth” can work over relatively short distances. According to the specifications (versions 1.1 and 1.2), it has two classes of adapters: Class 1 (Class A) supports up to 100 meters, and Class 2 (Class B) works within 10 meters (still the most common class among the specifications) .
Currently, the newest Bluetooth specification is 4.0. The Bluetooth SIG approved the specification on June 30, 2010. The Bluetooth low energy protocol supports the transmission of data such as sensors of temperature, pressure, humidity, speed of movement and others based on this standard can transmit information to various devices: mobile phones, personal computers, smartphones and other similar mobile products.
Bluetooth technology can also be used in a variety of areas mobile life. You can use it for the following purposes without any difficulty:
- For automatic synchronization between devices. For example, as soon as you enter new data into the address book on your laptop, the corresponding entries on your desktop computer are automatically modified, and vice versa
- For automatic backup synchronization. An example would be this situation: the manager changed your action plan while you are on vacation. The office PC sends changes to your mobile device, which automatically connects to the laptop and transmits the modified schedule
- To use a laptop PC as a speakerphone. By connecting the wireless headset to your laptop, you can use it in the office, car or home
- To connect all participants in the exchange of information. While at any business event, you can quickly discuss an issue of interest with all its participants. In addition, you can perform control functions remotely. For example, turn on the projector
- To convey various multimedia content from anywhere. The camera connects to your phone (wirelessly) and you add comments using the keyboard on your phone or laptop. Photos and text are sent to the recipient
All of the above is just the smallest part where Bluetooth wireless technology can be used. Now such exotic options are already appearing, such as embedding modules running on this technology into printers, memory cards and various other devices.
In the near future, Bluetooth technology, in addition to mobile phones, smartphones, and other interconnected devices, will even be built into household appliances. Just imagine it: a TV, vacuum cleaner, refrigerator, microwave oven and other home appliances can be controlled using a smartphone - just like with a universal control panel. In addition, alternative solutions are currently being developed that should seriously compete with the so-called “blue tooth” and even possibly surpass this technology.
A modern person is surrounded by an incredible number of mobile and electronic devices, and therefore he must be aware of the latest news of new technologies and know well what the basic concepts and terms of communication means. One of the most common technologies for building communication networks in the world is Bluetooth (bluetooth, bluetooth) - function wireless communication, without which in our time it is no longer possible to do.
Today, all models of mobile devices are equipped with wireless technology Bluetooth, and its latest version Bluetooth 4.0 is built into all flagship mobile devices Samsung and Apple companies. The fourth version of Bluetooth is the most advanced; it allows you to wirelessly transfer data from one smartphone or tablet to another at speeds of up to one megabit per second at a distance of 100 meters.
Bluetooth technology is designed to enable data transmission not only between similar devices, for example, between two smartphones, but also between devices various types. For example, computer and mobile phone. Thanks to Bluetooth, a wireless connection is created, with which you can transfer any information, including photos, video and audio files from one medium to another. Bluetooth is also used to connect a controlled device to a controller or signal transmission, allowing you to use headphones wirelessly.
Translated from English, the word "Bluetooth" means "blue tooth". It was not by chance that wireless communication technology was named this way. Bluetooth is the nickname of the Danish Viking king Harald Bluetooth, who lived in the 900s and is famous for uniting Norway and Denmark. He got his nickname as the Viking king because of his front tooth, which was darkened. When choosing a name, the developers of Bluetooth technology apparently decided that, by analogy with the king-unifier of the lands, it would unite computers, mobile phones, tablets and other telecommunications devices with each other.
The operating principle of Bluetooth technology is based on the use of radio communication in the ISM range, which is free from the need for licensing and does not require large investments to purchase equipment. The level of resistance and privacy when using Bluetooth is high, since data transmission occurs according to a pseudo-random algorithm and the frequency switching sequence is known only to the devices themselves.
The latest models of all mobile phones, tablets and laptops are equipped with Bluetooth, the presence of which is indicated by a logo icon in the case or on the screen of the mobile device. When a Bluetooth connection is established, a corresponding icon appears on the screen, and when exchanging data, an additional indication appears.
In addition to mobile devices, bluetooth technology used in desktop computers to provide communication between cameras, mice, keyboards, printers, scanners, headsets and headphones. All this equipment can communicate at a distance of up to 100 meters with Bluetooth adapters with flash drives, which can be found on sale today in any hardware store. Sometimes wireless communication is supported even between devices located in different rooms.
To connect various devices to a personal computer via Bluetooth, you need to install a Bluetooth connector port on the computer, which in shape looks like a simple flash drive and connects via USB. The program and drivers for working with Bluetooth are usually included in the kit; if they are not, you must use a universal program for working with BlueSoleil devices.
When establishing a connection between two devices, one of them is the master and the other is the slave. On both devices you need to turn on Bluetooth and continue scanning bluetooth wireless network. The list of available devices is displayed on the mobile phone screen and in the program on the computer. The device name can be set. To connect via Bluetooth, you need to know the name of the device you want to connect to and find it in the list. Then a password is entered on one of the devices, and on the second, this password must be confirmed. After this, the connection is established and data can be exchanged between the devices that have become paired. The Bluetooth port connected to the computer is usually equipped with a light indicator; when there is a connection and data transfer, it lights up and flashes blue or green.
Deserves special attention bluetooth headphones, which allow while driving, playing sports and walking. A wireless Bluetooth headset is attached to the ear, and the phone itself can be in a pocket or bag at this time. The headset has a button that is used to answer and allows you to adjust the volume. Call quality in use bluetooth headphones high, and the low power of the Bluetooth signal eliminates the harmful effects of mobile communications on health.
Using Bluetooth, you can exchange information between electronic multimedia devices: computers, mobile phones, etc. Bluetooth allows them to communicate on the inexpensive, widely available 2.45 GHz frequency. The established connection is reliable if the gadgets are located at a distance of up to 100 m.
Bluetooth is a wireless radio technology. It is designed to combine various digital devices. Bluetooth 4.0 version is energy saving and compatible with previous ones. This technology allows you to increase the operating time of the device after fully charged from the battery more than five times. In addition, the data exchange speed and connection stability have increased. The latest version 4.1 has a number of improvements regarding communication with mobile devices. Bluetooth technology uses short-range transmitters. There are two types: built directly into the device, external - connected via a PC card or USB port. It differs from IrDA (infrared port) in its larger range and high speed of information transfer. For Bluetooth there is no need for line of sight to the receiver. High speed IrDA devices were not widely available. They have been replaced by modern ones - Bluetooth, WiFi.
No cables are required to connect Bluetooth devices and transmit multimedia information. Both devices must have a built-in Bluetooth adapter. When it is activated, each device begins searching for another one within the acceptable range of the signal. Currently, the radius has increased from 10 m to 100 m (in an apartment 30-40 m). This is associated with the emergence of a large number of peripheral Bluetooth devices that work without bulky, inconvenient wires: keyboards, mice, headphones, modems.
The Bluetooth frequency range of 2.45 GHz is universally accessible to everyone. Federal Commission communications limits the range used by devices. The problem is that there are so many of them: bluetooth, wireless networks, microwave ovens. Audio and video equipment operating in the Home RF range is even more common. Increasing the Home RF range will cause conflict between the two.
Alarm, security, and radio communication devices operate at a frequency of 2.45 GHz - they also create interference. To solve this problem, Bluetooth uses fast frequency hopping. This restructuring makes it possible to transmit data faster than others operating at the same frequency. Reducing interference makes the Bluetooth connection more stable and strong.
Each user who wants to take advantage of wireless technology must make sure that the device has a Bluetooth microchip, otherwise it must be purchased and installed. On the computer, the adapter is connected to a USB port. The system itself will automatically detect a new device within range. Typically no driver installation is required. If the operating system specifies the adapter as unknown device, then install the driver from the disk included in the kit.
After the driver installation is completed, you need to activate Bluetooth to start searching for other devices. The adapter must be active on both devices. If the scan result is positive, a list of available devices is displayed. Find what you need, pair and start transferring data.
If you think about it, you will realize that you have no idea how most of the functions of the electronic devices you are familiar with work. I will try to fill these gaps in a series of educational articles. It will start with Bluetooth, a wireless communication technology that no smartphone can do without. Read about how it appeared, why it was named that way, what it is and what it will become in the near future.
History of the name Bluetooth
In 1998, Intel engineer Jim Cardack was part of a large development team working on short-range radio technology. A communication system that could connect computers and mobile phones with a universal communication protocol.Many names were tried for the technology, but none of them suited the company’s management. Some were somewhat cumbersome, others did not reflect the essence of the project. Then, Jim Kardak heard from his Swedish colleague a story about a small Norwegian village.
It is known only for one ancient landmark. The Jelling rune stones are installed there.
Now they are protected from bad weather and vandals by durable glass, behind which a constant temperature is maintained, but for more than a thousand years the stone surface was watered by rain and wind, so now the stones of Jelling bear little resemblance to the monuments that were once here.
The smallest and oldest of them was erected by King Gorm of Denmark in honor of his wife, Thyra. The larger stone is the work of their son, whose name, translated into English, sounds like Harold Bluetooth (Blue-toothed). The inscription on it reads "Harald, who conquered all Denmark and Norway, who baptized the Danes."
The story about the ruler who united such dissimilar peoples attracted Kardak and he decided that the name “Bluetooth” would make a good code name. We need to name the project something while the debate continues. That's all.
After long meetings and approvals, they decided to make “Personal Area Networking” or PAN (Personal Area Networking) the official name, but three weeks before the release, lawyers said that they could not register a trademark for something with such a common name. There was no choice left, and the technical name was assigned to the protocol - the name of the ancient king - Bluetooth.
As for the logo, it means: Harald Bluetooth. “ХБ”, written in the runic alphabet, merged together to form something of an ancient signature.
A thousand years ago, the Danish king ordered stones to be carved and erected in memory of his deeds, and a century later his name was immortalized on every smartphone.
Bluetooth hardware
I think there is hardly a single person among the readers of this article who has never used Bluetooth, so I will not dwell on what this technology is for. It’s better to tell you right away how it turns out that files move as if through the air from one phone to another.
At first, Bluetooth operation was provided by a separate, inconspicuous small chip, which was no different from other components soldered on the phone board.
However, over time, miniaturization, spurred by the pursuit of thinner phones and early smartphones, forced engineers to create chips that combine Wi-Fi, FM radio and Bluetooth under one lid. So these communication protocols could use one antenna, and in the event of a breakdown it is much easier to replace one chip than several soldered throughout the board.
But in modern smartphones you most likely will not find a combined wireless interface chip.
Nowadays, it is customary to integrate Bluetooth into a silicon crystal that combines a processor, video accelerator and other computing elements.
It is up to the processor manufacturer to build network functionality directly into the chip or make it a separate chip. You can still find individual Bluetooth chips from MediaTek on sale, but gradually this approach to component layout is becoming a thing of the past.
Operating principle of the protocol
As for the transfer process, by selecting the file in the menu operating system, you activate a radio transmitter operating in a limited frequency range in the 2.4 GHz region, the so-called ISM - Industry, Science and Medicine - part of the spectrum allocated specifically for the needs of various high-tech devices.Bluetooth begins to monitor all signals within these limits. The smartphone on the other end does the same - it tries to isolate familiar greeting sequences from the noise of interference.
It is worth keeping in mind that formally Bluetooth is both a receiver and a transmitter, but the chip cannot operate in both modes at the same time. The exception is the sound in Bluetooth headsets, but this aspect of the technology deserves a separate story.
Once the phones have discovered each other, the real magic begins. The first Bluetooth controller takes on the role of a transmitter, and the second becomes a receiver. The transmitter forms a special pattern from radio waves, which changes 1600 times per second, “jumping” from one of the available 79 frequencies (ranging from 2.401 GHz to 2.480 GHz) to another in an almost random order.
The template acts as an identifier. Only devices configured with the same template will be able to exchange files. At the same time, for other devices the transmitted information is no different from ordinary radio interference. This makes it possible to achieve not only privacy, but also unhindered simultaneous operation of several receiver-transmitter pairs, for example, in the same room.
Immediately before being sent via Bluetooth, the data is divided into packets - blocks of data designed in a certain way, accompanied by instructions for assembling the source file from them.
The receiver processor processes these packets, puts them into one file and places it in the device's permanent memory. If a package is found missing, it is re-queried.
This whole process takes much less time than it took to read his explanation - usually from a few seconds to a couple of minutes. The transfer speed of a file depends mainly on its size.
Brief version history
Some of our readers may remember a time when transferring files via Bluetooth was a thing of the past. A single ringtone could be transmitted for tens of minutes, and the process was accompanied by disconnections. There were also compatibility problems between different devices (say, LG and Nokia). It's all about versions. No product is perfect from day one. Communication protocols are constantly being improved and adjusted.So, Bluetooth 1.0 was terrible, and was essentially a demo. Fortunately, in real life almost no one had time to encounter him.
Bluetooth 1.1 and 1.2 were a little better, but did not differ fundamentally from the first version. With them, the developers mainly focused on fixing bugs and improving the stability of the protocol.
It was only on November 10, 2004, when Bluetooth 2.0 was released, that the technology went to the masses. With the introduction of EDR (Enhanced Data Rate), data transfer rates reached 2.1 Mbps, and Bluetooth quickly gained immense popularity.
The next big step forward was the release of Bluetooth 4.0, which actually combined several communication protocols under one name: regular, high-speed and low-power. The latest one, Bluetooth Low Energy, was promoted as perfect solution for miniature devices of the Internet of Things era, which never came. But the economical protocol was useful in creating headsets, wireless headphones and fitness bracelets.
In this mode, scanning the radio range does not necessarily wake up the device. Using Bluetooth Low Energy, a smartphone can recognize, for example, a headset and maintain communication with it without leaving standby mode.
In addition, new versions of this wireless protocol are trained to parallelize broadcasting. This is not about simultaneous communication with several devices (this has been implemented a long time ago), but about distributing communication bandwidth between different applications.
Since space in each data packet is limited, previously applications wanting to transfer data via Bluetooth competed for it. With the release of Bluetooth 4.0, developers can specify the contents of broadcast packets and have the radio send each application's data in a separate set of packets.
As with scanning, the technology now allows you to adjust the frequency of transmission of request packets to maintain a balance between power and Bluetooth functions, such as scanning or connecting to a wireless gamepad.
The most common modification now is Bluetooth 4.2, with a more complex and secure procedure for establishing a connection between devices than the original modification.
In December, Bluetooth 4.2 turns three years old - a respectable age, so in the coming 2018, most smartphones, at least from the middle and high price segments, will have Bluetooth 5.0 on board, which is even faster, energy efficient and stable.
Compared to version 4.2, the new Bluetooth has twice the maximum data transfer speed - 6.25 MB/s, and a much larger radius. Measurements in laboratory conditions, which are given in the characteristics of the protocol, indicate an increase in the communication radius from 10 to 40 meters indoors and from 50 to 200 meters outdoors.
For particularly power-hungry applications and fast transfer of large amounts of data, a broadcast mode with an increased packet has been added.
Bluetooth Special Interest Group, the current developers of the protocol, continue to develop the topic of the Internet of Things and have introduced a daisy-chain scheme for connecting devices for it. Simply put, with Bluetooth 5.0, data can be transferred not only directly between a smartphone and a smart light bulb, but also through a system of intermediaries - repeaters, which will be played by other elements smart home.
Fortunately, with the release of new versions, the protocol does not lose support for the old ones - this is called backward compatibility. So Bluetooth 5.0 will easily establish a connection with Bluetooth 3.0, but data transfer will be limited by the speed of the minor protocol and, of course, all these new features will not work.
Conclusion or a few words about the future of the protocol
Since 1994, Bluetooth has become an integral attribute any smartphone, turned out to be in demand in a variety of devices, from smart light bulbs to gamepads. However, it seems that the peak of the protocol’s popularity has already passed.At least we are using its basic functionality less and less often - transferring files from device to device without intermediaries.
It is unlikely that the technology will regain its former popularity as a means of transferring files, at least in those countries where there is high-speed Internet, but Bluetooth is still indispensable for other tasks.
More and more companies are abandoning the 3.5 mm jack in their smartphones and there is no doubt that headsets will be connected to new flagships via Bluetooth. But whether the spread of Bluetooth 5.0 will lead to a new rise in the popularity of the technology, only time will tell.
The Bluetooth interface has now become quite widespread among different types devices, in particular personal computers, mobile phones, tablets and others. Of course, users are not immune from various problems. Most often, it is not difficult to understand the causes of problems; it is enough to be familiar with the basic principles of operation of the specified interface. "Bluetooth" - what is it? How to use it?
Features of the technology
Bluetooth is a short-range wireless interface that was created in 1994 by engineers from Ericsson, located in Sweden. In 1998, a number of companies created a special organization, the Bluetooth Special Interest Group (Bluetooth SIG), which is still working in the development, promotion and implementation of this technology. At the moment, the number of companies that have become members of the association has exceeded 13 thousand.
The main advantage of this technology is that Bluetooth connection does not require large resources in terms of energy consumption, and the cost of transceivers is relatively low compared to other wireless transmission technologies. All this allows you to use this technical solution even in small-sized devices with miniature batteries. Equipment manufacturers are not required to pay anything to the creators of the technology for using the described interface. This fact played an important role in such a wide distribution of this interface in a variety of devices.
What is it for?
We briefly looked at what Bluetooth is. What is this useful thing, it’s already clear. But you still need to figure out how to use it. The main purpose of this technology is to create personal networks that provide opportunities for data exchange between gadgets located nearby. These can be laptops, desktop computers, mobile devices, peripherals, and many others that fall into this category.
Application
Bluetooth can be used for various purposes. We have already learned that this is a device that allows you to connect several devices into a network. But how does the connection happen? In the case of two gadgets, the connection is carried out according to a “point-to-point” scheme, and in the case of a large number of devices it will already be a “point-to-multipoint” scheme. Regardless of the circuit used, a master device and slaves are allocated.
The master device sets a template that is used by all slaves, and is also responsible for synchronizing all devices. Through this connection, a piconet is formed. Within one such solution, it is possible to combine one master and seven slave devices. In addition, it is possible to add several more devices to the piconet, which will be slaves, but only in a temporarily blocked status. They do not take part in information exchange, but are synchronized with the host using the Bluetooth interface. What this is becomes clear if you imagine how data is sent from one source to everyone else in real time. This is convenient and opens up a lot of possibilities for organizing work.
Maximum number of devices
Another level of interconnection is the integration of several piconets into a single distribution network. To do this, a device that is a slave in one piconet takes on the tasks of a master in another. In this case, the peculiarity is that piconets belonging to the same distribution network use different patterns and are not synchronized with each other. One distribution network cannot include more than 10 piconets. It turns out that by organizing a distribution network that includes Bluetooth devices, it is possible to combine up to 71 devices in total.
Features of data transfer
A radio channel of 2.4-2.4835 GHz is used, supplemented by the method of pseudo-random tuning of the operating frequency. The specified range is divided into 79 channels, for each of which a bandwidth of 1 MHz is allocated. Upper and Bottom part range contains unused bands that are considered guard bands. Data transmission is carried out using Gaussian phase modulation, which involves changing the carrier frequency over time according to the Gaussian curve, and this significantly limits the spectrum of the emitted signal.
The Bluetooth adapter exchanges data within time intervals, the length of which is 625 μs. The transmission of each slot ends with a transition to a new frequency channel. The data link layer assumes that data is exchanged in packets, each of which is one to five slots long. A certain part of them can be reserved for synchronous channels intended for broadcasting streaming data. It turns out that transmission can be carried out not only with synchronous data, but also with asynchronous data.
The Bluetooth device specification provides the ability to use two types of communication: synchronous with the establishment of a connection, and asynchronous, in which a connection is not established. The use of the first option is relevant when creating point-to-point channels between master and slave devices. The purpose of the second is to organize a point-to-multipoint interface between the piconet master device and all slaves.
Bluetooth device classes
Depending on the power and range efficiency of the Bluetooth adapter, there are three classes of transceivers. The most common option, relevant for use in most computers and mobile devices manufactured modern industry, are second class transceivers. Medical equipment is equipped with low-power Class 3 transmitters, and the longest-range modules belonging to Class 1 are used in control and monitoring systems for industrial equipment.
Settings Features
If you want to install Bluetooth on your computer and then use it to pair with any devices, then you should be familiar with the features of its configuration. Using this technology, you can use short-range radio waves to connect to wireless networks, as well as gain access to peripheral devices compatible with the technology version: printer, mouse, mobile phone, as well as other computers and communicators.
Because we're talking about about a wireless connection, that is, carried out via radio waves, then any peripheral device can be moved in space, and the connection will not be lost if it does not leave the “visibility” zone. If you want to connect, you should know that this is done automatically when the device comes within range of the transmitter. You only need to make all the necessary settings once. Most laptop models have built-in transmitters from the start; you just need to configure them correctly so that later everything works without interruptions.
Setting up a Bluetooth device for Windows
To carry out this operation, you need to perform very specific actions. First you need to make sure that your laptop has this adapter. After this, you need to download all the necessary drivers. After activating the driver installer and running the Add Device Wizard, everything will be determined automatically.
Once the device is detected, you will need to add it. If the system is unable to find it, you should make sure that the device is fully charged, has power, is turned on, and is located within range. Information about the range of any device can be found in the accompanying documentation. After the detailed component check is completed, you need to restart the Add Device Wizard.
Problems that may arise
If you are puzzled by how to turn on Bluetooth, you may note that if the component itself is not present on the laptop’s taskbar, the corresponding icon may be present. It must be hidden. To do this, click on the icon, and then on the “Customize” item.
When Bluetooth devices are turned on, the display shows a list of all paired devices that are available in range. Moreover, each, as mentioned earlier, has its own range, which must be taken into account when pairing.
Features of work
All latest models of phones, tablets and laptops receive a Bluetooth module as a mandatory component, the presence of which is confirmed by a logo icon on the screen or body of the device. When a connection is established, the corresponding logo will appear on the screen, and the data exchange is accompanied by additional indication. Manufacturers are now integrating Bluetooth devices into tablets, phones and computers.
In addition to mobile devices, this technology is applicable for desktop computers, to ensure communication between mice, keyboards, digital cameras, scanners, printers, headphones and a variety of headsets. This equipment supports data exchange over a distance of up to 100 meters. Sometimes wireless support is possible even when using devices located in different rooms.
Pairing different devices
If you use Bluetooth for a phone or other devices when connecting to a PC, you need to install a port connector on the computer that is shaped like a regular flash drive connected via USB. Drivers and necessary programs are usually supplied with the equipment, but if they are not available, you can always use the official website to obtain the necessary applications.
If we consider a Bluetooth device for a phone, then those who use this technology are the most popular. With their help, you can talk on the phone even when your hands are busy: when playing sports, driving a car, etc. If you know how to turn on Bluetooth to activate the headset, you can always free your hands while you talk by phone. The device itself can be in a bag or pocket at this time.
Features of using Bluetooth in phones and smartphones
The first phones were capable of transmitting only voice, but in recent decades they have advanced so far in their development that they can now send text, graphics, video and many other types of data to other devices. Not the least role in this is played by the Bluetooth radio module (the literal translation into Russian is “blue tooth”), which today can be found in almost every mobile phone, as well as in laptops, computers and as separate devices.
Bluetooth Basics
Initially, the Bluetooth radio module was invented as an alternative to a wired connection for various devices. Thanks to it, there is no need to constantly carry and connect various cables when necessary. Today it has become a global standard, and you can use Bluetooth in every corner of our planet. To operate, this radio module uses a frequency of 2.4 GHz (low-frequency radio communications). This range is not subject to mandatory licensing, so anyone can work with it.
Depending on the class, Bluetooth modules can operate in a range of up to 1 to 100 meters, but this is in theory. In practice (in conditions other than ideal), the range of action in each class will be 10-20% less than the reference one. Physical obstacles do not interrupt the radio signal, but only slightly limit its range. This is its main difference from the older method of data transmission in the phone - IrDA.
Externally, Bluetooth is a small microchip built into another electronic device. This article will discuss the capabilities of Bluetooth as part of a mobile phone or smartphone.
On the oldest phones you can still find the earliest Bluetooth specification - 1.0. It was far from perfect, as it allowed data transfer at a maximum speed of 721 Kbps and was characterized by poor compatibility between devices from different manufacturers. Versions 1.1 and 1.2 corrected this bug and were widely used in mobile phones a few years ago. Today, the most popular versions are Bluetooth 2.0 and 2.1. The first (Bluetooth 2.0) added EDR support, which increased data transfer speeds to 3 Mbit/s, and the second (Bluetooth 2.1) introduced the energy-saving Sniff Subrating technology. Manufacturers have installed Bluetooth radio modules version 3.0 on a number of recent mobile products, the main difference from previous ones is the ability to transfer data at speeds of up to 24 Mbit/s (comparable to the data transfer speed via Wi-Fi).
The Bluetooth capabilities of a phone are largely determined by the set of supported profiles. Among the most useful and popular profiles are Handsfree (allows you to use a wireless headset for conversations), Serial Port (PC serial port emulator), Dial Up Networking (network dialing), File Transfer (file transfer), Basic Printing (printing images ), A2DP (allows you to transmit high quality audio to wireless headphones). Each phone may have a different set of supported profiles, but the capabilities that will be described in the last three sections can be offered to you by any modern phone that has this radio module installed.
Advantages and disadvantages of wireless communication via Bluetooth on your phone
The advantages of the Bluetooth radio module in the phone include the following features:
- the presence of Bluetooth allows you to exchange data with other devices (naturally, also equipped with the same module) without using an additional accessory - a data cable;
- the presence of a Bluetooth module has very little effect on its cost, so it is installed in almost all modern models of mobile phones and smartphones (the only exceptions are extremely cheap phones designed only for making calls);
- to use the Bluetooth module in your phone you will need a minimum of additional knowledge;
- the possibility of interference between different Bluetooth phones that are in close proximity to each other is excluded;
- when connecting two devices with Bluetooth modules in each of them, there is no need to purchase additional accessories;
- The Bluetooth radio module uses battery power more economically than Wi-Fi.
The disadvantages of Bluetooth wireless technology in a phone are as follows:
- Despite the moderate rate of battery discharge when Bluetooth is turned on, this module should still be used carefully, especially if it is not possible to recharge your mobile phone in the near future;
- limited operating radius of the module in the phone - usually up to 10 meters in open space. Concrete floors buildings can reduce this radius by 1.5-2 times.
Bluetooth in the phone for communication
Using a Bluetooth headset with a phone equipped with this radio module allows you to free your hands while talking on the phone. The headset is attached to the user's ear, and the phone itself can easily lie in a pocket at this time. This method is especially popular among busy people who often have to answer calls, as well as among supporters active image life, car enthusiasts.
Today there are so many ways to communicate via mobile phones that it is difficult to say anything new about any of them. Unfortunately, most of them work on a paid basis: regular calls, SMS, MMS, emails, ICQ messages or messages in social network. All of them will be paid in accordance with the current tariffs of your mobile operator. There are, of course, very loyal tariff plans, where some services will be very cheap or even free, but these are special cases. Nevertheless, there is a way to communicate for free, and it is implemented precisely through the Bluetooth wireless module.
In addition to the Bluetooth phones themselves, you will need only one thing: a simple Java application that will provide the interface necessary for communication. Quite a lot of similar programs have been created, but they are called very similar: Bluetooth Chat, Blue Chat, Blueeee! IM. The vast majority of these applications can be quickly and freely found and installed on your mobile phone.
After installation, all you need to do is activate Bluetooth on your phone and make it “visible” to other devices. After that, you can turn on the search and try to find people to talk to. All messages sent and received will be absolutely free, and the chat can support up to ten dialogues simultaneously in private mode or real chat - when all messages are visible to all connected users.
Bluetooth Chat program interface
Bluetooth in the phone for work
A mobile phone with Bluetooth can be an excellent assistant if you need to surf the Internet from a computer or laptop. It is difficult to surprise anyone today with the use of a mobile phone to access the Internet. But in some cases, users don’t even realize that having a PC or laptop with a built-in or external Bluetooth module at hand, they can check mail, ICQ or their social network page with much greater comfort. To do this, you need to turn on Bluetooth on your phone and computer (or laptop), activate the ability to be detected by other devices on each of them, exchange control codes (although you can connect without them - it all depends on the selected connection settings). When the computer and phone “see” each other, in the PC settings you should select the “Dial-up network access connections” service. That's it, now you can access the Internet using your mobile phone, which in this case will serve as a GPRS modem.
Having only a phone and a laptop (or PC) with Bluetooth modules at hand (and in many modern laptops it is installed by default), you can quickly transfer files from one device to another, including synchronizing organizers, phone books, creating backups important data, exchange electronic business cards and much more.
Bluetooth on your phone for entertainment
A mobile phone with Bluetooth can be a good replacement for a remote control. remote control for your computer or laptop. In order to connect two devices using it, you will need to install special software on your phone. For example, this could be anyRemoote or Bluetooth Remote Control.
Bluetooth Remote Control program interface
In the application settings, you can specify which programs the phone will work with as a control panel. These can be audio and video players, image and presentation viewers, and a number of other applications.
If your phone has Bluetooth with the A2DP profile, then you can safely buy Bluetooth headphones and listen to music with them. This is extremely convenient - you don’t have tangled wires, and the music jack on the case doesn’t become loose (which is a big problem for phones that have been actively used for 2-3 years). In order to connect headphones to your phone and seamlessly transfer music to them, you need to follow the standard steps to turn on the “visibility” of each of them, as well as search for and add each other to the list of connected devices.
Examples of Bluetooth headphones
By the way, in fact, you can control not only music or programs on your PC, but also many different gadgets. So, a few years ago the company released Bluetooth Car 100 - a gadget in the form of a small car that could be controlled using a phone with a Bluetooth radio module.