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64-453: Although OBEX was initially designed for infrared, it has now been adopted by Bluetooth , and is also used over RS-232 , USB , WAP and in devices such as Livescribe smartpens. OBEX is similar in design and function to HTTP in providing the client with a reliable transport for connecting to a server and may then request or provide objects. But OBEX differs in many important respects: OBEX works by exchanging objects , which are used for

128-492: A round-robin fashion. Since it is the master that chooses which slave to address, whereas a slave is (in theory) supposed to listen in each receive slot, being a master is a lighter burden than being a slave. Being a master of seven slaves is possible; being a slave of more than one master is possible. The specification is vague as to required behavior in scatternets. Bluetooth is a standard wire-replacement communications protocol primarily designed for low power consumption, with

192-782: A built-in Bluetooth radio, others require an external adapter, typically in the form of a small USB " dongle ". Unlike its predecessor, IrDA , which requires a separate adapter for each device, Bluetooth lets multiple devices communicate with a computer over a single adapter. For Microsoft platforms, Windows XP Service Pack 2 and SP3 releases work natively with Bluetooth v1.1, v2.0 and v2.0+EDR. Previous versions required users to install their Bluetooth adapter's own drivers, which were not directly supported by Microsoft. Microsoft's own Bluetooth dongles (packaged with their Bluetooth computer devices) have no external drivers and thus require at least Windows XP Service Pack 2. Windows Vista RTM/SP1 with

256-465: A cellular phone and a vehicle's audio system. At the time, Sony/Ericsson had only a minor market share in the cellular phone market, which was dominated in the US by Nokia and Motorola. Due to ongoing negotiations for an intended licensing agreement with Motorola beginning in the late 1990s, Vosi could not publicly disclose the intention, integration, and initial development of other enabled devices which were to be

320-421: A distance greater than the line of sight is required. Occasionally when conditions are right, UHF radio waves can travel long distances by tropospheric ducting as the atmosphere warms and cools throughout the day. The length of an antenna is related to the length of the radio waves used. Due to the short wavelengths, UHF antennas are conveniently stubby and short; at UHF frequencies a quarter-wave monopole ,

384-621: A given link depends on several qualities of both communicating devices and the air and obstacles in between . The primary attributes affecting range are the data rate, protocol (Bluetooth Classic or Bluetooth Low Energy), transmission power, and receiver sensitivity, and the relative orientations and gains of both antennas. The effective range varies depending on propagation conditions, material coverage, production sample variations, antenna configurations and battery conditions. Most Bluetooth applications are for indoor conditions, where attenuation of walls and signal fading due to signal reflections make

448-469: A lower power consumption through a reduced duty cycle . The specification is published as Bluetooth v2.0 + EDR , which implies that EDR is an optional feature. Aside from EDR, the v2.0 specification contains other minor improvements, and products may claim compliance to "Bluetooth v2.0" without supporting the higher data rate. At least one commercial device states "Bluetooth v2.0 without EDR" on its data sheet. Bluetooth Core Specification version 2.1 + EDR

512-410: A membership of over 30,000 companies worldwide. It was established by Ericsson , IBM , Intel , Nokia and Toshiba , and later joined by many other companies. All versions of the Bluetooth standards are backward-compatible with all earlier versions. The Bluetooth Core Specification Working Group (CSWG) produces mainly four kinds of specifications: Major enhancements include: This version of

576-475: A radio technology called frequency-hopping spread spectrum . Bluetooth divides transmitted data into packets, and transmits each packet on one of 79 designated Bluetooth channels. Each channel has a bandwidth of 1   MHz. It usually performs 1600   hops per second, with adaptive frequency-hopping (AFH) enabled. Bluetooth Low Energy uses 2   MHz spacing, which accommodates 40 channels. Originally, Gaussian frequency-shift keying (GFSK) modulation

640-422: A serious name, Bluetooth was to be replaced with either RadioWire or PAN (Personal Area Networking). PAN was the front runner, but an exhaustive search discovered it already had tens of thousands of hits throughout the internet. A full trademark search on RadioWire couldn't be completed in time for launch, making Bluetooth the only choice. The name caught on fast and before it could be changed, it spread throughout

704-419: A short range based on low-cost transceiver microchips in each device. Because the devices use a radio (broadcast) communications system, they do not have to be in visual line of sight of each other; however, a quasi optical wireless path must be viable. Historically, the Bluetooth range was defined by the radio class, with a lower class (and higher output power) having larger range. The actual range of

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768-425: A single GET command and its response, the only headers involved being connection id, name and end-of-body. Before issuing it, a CONNECT command should have been sent for establishing some parameters of the connection, including the connection id. Other commands are: put, setpath, action, abort, disconnect. Some other notable headers include: type, time, description, target. After the client (e.g., computer) connects to

832-474: A single response object. The only header has 0x49 as its identifier, meaning that it is an "End of Body", the last chunk of information (also the only one, in this case). The first two bits of 0x49 are 01, meaning that the content of this header is length-prefixed data: the two next bytes 0x00 0x2F tells the length of this data (in decimal, 47), the succeeding ones are the data, in this case a phonebook comprising only an empty vCard of 47 bytes. This example shows

896-402: A variety of purposes: establishing the parameters of a connection, sending and requesting data, changing the current path or the attributes of a file. Objects are fields and headers . As an example, the following may be the object used for requesting the phonebook from a mobile: This object contains two fields (command and length) and two headers. The first field (command) specifies that it

960-879: Is a bind rune merging the Younger Futhark runes [REDACTED]  (ᚼ, Hagall ) and [REDACTED]  (ᛒ, Bjarkan ), Harald's initials. The development of the "short-link" radio technology, later named Bluetooth, was initiated in 1989 by Nils Rydbeck, CTO at Ericsson Mobile in Lund , Sweden. The purpose was to develop wireless headsets, according to two inventions by Johan Ullman , SE 8902098-6 , issued 1989-06-12   and SE 9202239 , issued 1992-07-24   . Nils Rydbeck tasked Tord Wingren with specifying and Dutchman Jaap Haartsen and Sven Mattisson with developing. Both were working for Ericsson in Lund. Principal design and development began in 1994 and by 1997

1024-405: Is a packet-based protocol with a master/slave architecture . One master may communicate with up to seven slaves in a piconet . All devices within a given piconet use the clock provided by the master as the base for packet exchange. The master clock ticks with a period of 312.5   μs , two clock ticks then make up a slot of 625   μs, and two slots make up a slot pair of 1250   μs. In

1088-428: Is a considerable amount of lawful unlicensed activity (cordless phones, wireless networking) clustered around 900 MHz and 2.4 GHz, regulated under Title 47 CFR Part 15 . These ISM bands —frequencies with a higher unlicensed power permitted for use originally by Industrial, Scientific, Medical apparatus—are now some of the most crowded in the spectrum because they are open to everyone. The 2.45 GHz frequency

1152-417: Is a request for data (GET). The second field is the total size of the object, including the two fields. This object also contains two headers, specifically a "Connection ID" and a "Name". The first byte of each header is the header's name and its content type. In this case: A possible response, containing the requested data, could be: In this example, the phonebook is assumed short enough to be contained in

1216-467: Is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limited to 2.5 milliwatts , giving it a very short range of up to 10 metres (33 ft). It employs UHF radio waves in the ISM bands , from 2.402   GHz to 2.48   GHz. It

1280-444: Is an open-source implementation of OBEX in C . It provides functions for connecting over IrDA , Bluetooth , USB and TCP/IP , building objects and handling received data. An example schema of a client application is: Objects are sent by OBEX_Request . After calling OBEX_HandleInput , received data is processed in the callback function (which was specified when calling OBEX_Init ). The callback function can determine whether

1344-411: Is connecting to a Class 1 transceiver with both higher sensitivity and transmission power than a typical Class 2 device. In general, however, Class 1 devices have sensitivities similar to those of Class 2 devices. Connecting two Class 1 devices with both high sensitivity and high power can allow ranges far in excess of the typical 100 m, depending on the throughput required by

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1408-530: Is for cellphones , allowing handheld mobile phones be connected to the public switched telephone network and the Internet . Current 3G and 4G cellular networks use UHF, the frequencies varying among different carriers and countries. Satellite phones also use this frequency in the L band and S band . UHF channels are used for digital television broadcasting on both over the air channels and cable television channels . Since 1962, UHF channel tuners (at

1472-522: Is included with most Linux kernels and was originally developed by Qualcomm . Fluoride, earlier known as Bluedroid is included in Android OS and was originally developed by Broadcom . There is also Affix stack, developed by Nokia . It was once popular, but has not been updated since 2005. FreeBSD has included Bluetooth since its v5.0 release, implemented through netgraph . NetBSD has included Bluetooth since its v4.0 release. Its Bluetooth stack

1536-526: Is mainly used as an alternative to wired connections to exchange files between nearby portable devices and connect cell phones and music players with wireless headphones . Bluetooth is managed by the Bluetooth Special Interest Group (SIG), which has more than 35,000 member companies in the areas of telecommunication, computing, networking, and consumer electronics. The IEEE standardized Bluetooth as IEEE 802.15.1 but no longer maintains

1600-452: Is the standard for use by microwave ovens , adjacent to the frequencies allocated for Bluetooth network devices. The spectrum from 806 MHz to 890 MHz (UHF channels 70 to 83) was taken away from TV broadcast services in 1983, primarily for analog mobile telephony . In 2009, as part of the transition from analog to digital over-the-air broadcast of television , the spectrum from 698 MHz to 806 MHz (UHF channels 52 to 69)

1664-404: Is useful when transferring information between two or more devices that are near each other in low-bandwidth situations. Bluetooth is commonly used to transfer sound data with telephones (i.e., with a Bluetooth headset) or byte data with hand-held computers (transferring files). Bluetooth protocols simplify the discovery and setup of services between devices. Bluetooth devices can advertise all of

1728-652: The super-high frequency (SHF) or microwave frequency range. Lower frequency signals fall into the VHF ( very high frequency ) or lower bands. UHF radio waves propagate mainly by line of sight ; they are blocked by hills and large buildings although the transmission through building walls is strong enough for indoor reception. They are used for television broadcasting , cell phones , satellite communication including GPS , personal radio services including Wi-Fi and Bluetooth , walkie-talkies , cordless phones , satellite phones , and numerous other applications. The IEEE defines

1792-522: The 10th-century Danish king Harald Bluetooth . Upon discovering a picture of the runestone of Harald Bluetooth in the book A History of the Vikings by Gwyn Jones , Kardach proposed Bluetooth as the codename for the short-range wireless program which is now called Bluetooth. According to Bluetooth's official website, Bluetooth was only intended as a placeholder until marketing could come up with something really cool. Later, when it came time to select

1856-523: The Bluetooth Core Specification was released before 2005. The main difference is the introduction of an Enhanced Data Rate (EDR) for faster data transfer . The data rate of EDR is 3   Mbit/s, although the maximum data transfer rate (allowing for inter-packet time and acknowledgements) is 2.1   Mbit/s. EDR uses a combination of GFSK and phase-shift keying modulation (PSK) with two variants, π/4- DQPSK and 8- DPSK . EDR can provide

1920-582: The Feature Pack for Wireless or Windows Vista SP2 work with Bluetooth v2.1+EDR. Windows 7 works with Bluetooth v2.1+EDR and Extended Inquiry Response (EIR). The Windows XP and Windows Vista/Windows 7 Bluetooth stacks support the following Bluetooth profiles natively: PAN, SPP, DUN , HID, HCRP. The Windows XP stack can be replaced by a third party stack that supports more profiles or newer Bluetooth versions. The Windows Vista/Windows 7 Bluetooth stack supports vendor-supplied additional profiles without requiring that

1984-485: The Microsoft stack be replaced. Windows 8 and later support Bluetooth Low Energy (BLE). It is generally recommended to install the latest vendor driver and its associated stack to be able to use the Bluetooth device at its fullest extent. Apple products have worked with Bluetooth since Mac OS   X v10.2 , which was released in 2002. Linux has two popular Bluetooth stacks , BlueZ and Fluoride. The BlueZ stack

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2048-834: The R520m in Quarter 1 of 2001, making the R520m the first ever commercially available Bluetooth phone. In parallel, IBM introduced the IBM ThinkPad ;A30 in October ;2001 which was the first notebook with integrated Bluetooth. Bluetooth's early incorporation into consumer electronics products continued at Vosi Technologies in Costa Mesa, California, initially overseen by founding members Bejan Amini and Tom Davidson. Vosi Technologies had been created by real estate developer Ivano Stegmenga, with United States Patent 608507, for communication between

2112-645: The UHF radar band as frequencies between 300 MHz and 1 GHz. Two other IEEE radar bands overlap the ITU UHF band: the L band between 1 and 2 GHz and the S band between 2 and 4 GHz. Radio waves in the UHF band travel almost entirely by line-of-sight propagation (LOS) and ground reflection; unlike in the HF band there is little to no reflection from the ionosphere ( skywave propagation), or ground wave . UHF radio waves are blocked by hills and cannot travel beyond

2176-469: The UHF spectrum is used worldwide for land mobile radio systems, two-way radios used for voice communication for commercial, industrial, public safety, and military purposes. Examples of personal radio services are GMRS , PMR446 , and UHF CB . The most rapidly-expanding use of the band is Wi-Fi ( wireless LAN ) networks in homes, offices, and public places. Wi-Fi IEEE 802.11 low band operates between 2412 and 2484 MHz. A second widespread use

2240-502: The application. Some such devices allow open field ranges of up to 1 km and beyond between two similar devices without exceeding legal emission limits. To use Bluetooth wireless technology, a device must be able to interpret certain Bluetooth profiles. For example, Profiles are definitions of possible applications and specify general behaviors that Bluetooth-enabled devices use to communicate with other Bluetooth devices. These profiles include settings to parameterize and to control

2304-463: The attenuation increases with frequency. UHF TV signals are generally more degraded by moisture than lower bands, such as VHF TV signals. As the visual horizon sets the maximum range of UHF transmission to between 30 and 40 miles (48 to 64 km) or less, depending on local terrain, the same frequency channels can be reused by other users in neighboring geographic areas ( frequency reuse ). Radio repeaters are used to retransmit UHF signals when

2368-529: The communication from the start. Adherence to profiles saves the time for transmitting the parameters anew before the bi-directional link becomes effective. There are a wide range of Bluetooth profiles that describe many different types of applications or use cases for devices. Bluetooth exists in numerous products such as telephones, speakers , tablets, media players, robotics systems, laptops, and game console equipment as well as some high definition headsets , modems , hearing aids and even watches. Bluetooth

2432-524: The connection—but may subsequently operate as the slave). The Bluetooth Core Specification provides for the connection of two or more piconets to form a scatternet , in which certain devices simultaneously play the master/leader role in one piconet and the slave role in another. At any given time, data can be transferred between the master and one other device (except for the little-used broadcast mode). The master chooses which slave device to address; typically, it switches rapidly from one device to another in

2496-464: The first " Smart Home " internet connected devices. Vosi needed a means for the system to communicate without a wired connection from the vehicle to the other devices in the network. Bluetooth was chosen, since Wi-Fi was not yet readily available or supported in the public market. Vosi had begun to develop the Vosi Cello integrated vehicular system and some other internet connected devices, one of which

2560-496: The founding signatories and a total of five members: Ericsson, Intel, Nokia, Toshiba, and IBM. The first Bluetooth device was revealed in 1999. It was a hands-free mobile headset that earned the "Best of show Technology Award" at COMDEX . The first Bluetooth mobile phone was the unreleased prototype Ericsson T36, though it was the revised Ericsson model T39 that actually made it to store shelves in June 2001. However Ericsson released

2624-429: The horizon, but can penetrate foliage and buildings for indoor reception. Since the wavelengths of UHF waves are comparable to the size of buildings, trees, vehicles and other common objects, reflection and diffraction from these objects can cause fading due to multipath propagation , especially in built-up urban areas. Atmospheric moisture reduces, or attenuates , the strength of UHF signals over long distances, and

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2688-583: The industry, becoming synonymous with short-range wireless technology. Bluetooth is the Anglicised version of the Scandinavian Blåtand / Blåtann (or in Old Norse blátǫnn ). It was the epithet of King Harald Bluetooth, who united the disparate Danish tribes into a single kingdom; Kardach chose the name to imply that Bluetooth similarly unites communication protocols. The Bluetooth logo [REDACTED]

2752-530: The most common omnidirectional antenna is between 2.5 and 25 cm long. UHF wavelengths are short enough that efficient transmitting antennas are small enough to mount on handheld and mobile devices, so these frequencies are used for two-way land mobile radio systems , such as walkie-talkies , two-way radios in vehicles, and for portable wireless devices ; cordless phones and cell phones . Omnidirectional UHF antennas used on mobile devices are usually short whips , sleeve dipoles , rubber ducky antennas or

2816-483: The planar inverted F antenna (PIFA) used in cellphones. Higher gain omnidirectional UHF antennas can be made of collinear arrays of dipoles and are used for mobile base stations and cellular base station antennas . The short wavelengths also allow high gain antennas to be conveniently small. High gain antennas for point-to-point communication links and UHF television reception are usually Yagi , log periodic , corner reflectors , or reflective array antennas . At

2880-451: The power consumption in low-power mode. Ultra high frequency Ultra high frequency ( UHF ) is the ITU designation for radio frequencies in the range between 300  megahertz (MHz) and 3  gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (one decimeter ). Radio waves with frequencies above the UHF band fall into

2944-661: The public market due to its large market share at the time. In 2012, Jaap Haartsen was nominated by the European Patent Office for the European Inventor Award . Bluetooth operates at frequencies between 2.402 and 2.480   GHz, or 2.400 and 2.4835   GHz, including guard bands 2   MHz wide at the bottom end and 3.5   MHz wide at the top. This is in the globally unlicensed (but not unregulated) industrial, scientific and medical ( ISM ) 2.4   GHz short-range radio frequency band. Bluetooth uses

3008-413: The range far lower than specified line-of-sight ranges of the Bluetooth products. Most Bluetooth applications are battery-powered Class 2 devices, with little difference in range whether the other end of the link is a Class 1 or Class 2 device as the lower-powered device tends to set the range limit. In some cases the effective range of the data link can be extended when a Class 2 device

3072-574: The response has been completely received, and therefore whether the main program can exit from the while loop it is executing. PyOBEX provides partial support for OBEX in Python . nOBEX is a fork of PyOBEX with more complete OBEX support, and support for the Bluetooth Hands Free Profile to facilitate OBEX testing on automotive infotainment systems. OBEX is the foundation for many higher-layer "profiles": Bluetooth Bluetooth

3136-427: The same spectrum but somewhat differently . A master BR/EDR Bluetooth device can communicate with a maximum of seven devices in a piconet (an ad hoc computer network using Bluetooth technology), though not all devices reach this maximum. The devices can switch roles, by agreement, and the slave can become the master (for example, a headset initiating a connection to a phone necessarily begins as master—as an initiator of

3200-651: The server (e.g., mobile), a typical session consists in the client sending a number of objects and getting their responses from the server. As an example: The exchange may differ significantly depending on the service. For example, SyncML does not use SETPATH, while an OBEX push is made of just CONNECT (without a TARGET header), PUT and an optional DISCONNECT. The following protocols runs over OBEX, or have bindings to do so: Optional package javax.obex in Java APIs for Bluetooth provides an implementation of OBEX in Java . OpenObex

3264-449: The services they provide. This makes using services easier, because more of the security, network address and permission configuration can be automated than with many other network types. A personal computer that does not have embedded Bluetooth can use a Bluetooth adapter that enables the PC to communicate with Bluetooth devices. While some desktop computers and most recent laptops come with

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3328-460: The short-link technology an open industry standard to permit each player maximum market access. Ericsson contributed the short-link radio technology, and IBM contributed patents around the logical layer. Adalio Sanchez of IBM then recruited Stephen Nachtsheim of Intel to join and then Intel also recruited Toshiba and Nokia . In May 1998, the Bluetooth SIG was launched with IBM and Ericsson as

3392-401: The simple case of single-slot packets, the master transmits in even slots and receives in odd slots. The slave, conversely, receives in even slots and transmits in odd slots. Packets may be 1, 3, or 5 slots long, but in all cases, the master's transmission begins in even slots and the slave's in odd slots. The above excludes Bluetooth Low Energy, introduced in the 4.0 specification, which uses

3456-414: The slot antenna or reflective array antenna are used: the slotted cylinder, zig-zag, and panel antennas. UHF television broadcasting channels are used for digital television , although much of the former bandwidth has been reallocated to land mobile radio system , trunked radio and mobile telephone use. Since at UHF frequencies transmitting antennas are small enough to install on portable devices,

3520-428: The standard. The Bluetooth SIG oversees the development of the specification, manages the qualification program, and protects the trademarks. A manufacturer must meet Bluetooth SIG standards to market it as a Bluetooth device. A network of patents applies to the technology, which is licensed to individual qualifying devices. As of 2021 , 4.7 billion Bluetooth integrated circuit chips are shipped annually. Bluetooth

3584-402: The team had a workable solution. From 1997 Örjan Johansson became the project leader and propelled the technology and standardization. In 1997, Adalio Sanchez, then head of IBM ThinkPad product R&D, approached Nils Rydbeck about collaborating on integrating a mobile phone into a ThinkPad notebook. The two assigned engineers from Ericsson and IBM studied the idea. The conclusion

3648-517: The time, channels 14 to 83) have been required in television receivers by the All-Channel Receiver Act . However, because of their more limited range, and because few sets could receive them until older sets were replaced, UHF channels were less desirable to broadcasters than VHF channels (and licenses sold for lower prices). A complete list of US Television Frequency allocations can be found at Pan-American television frequencies . There

3712-399: The top end of the band, slot antennas and parabolic dishes become practical. For satellite communication, helical and turnstile antennas are used since satellites typically employ circular polarization which is not sensitive to the relative orientation of the transmitting and receiving antennas. For television broadcasting specialized vertical radiators that are mostly modifications of

3776-473: Was adopted by the Bluetooth SIG on 26 July 2007. The headline feature of v2.1 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 various 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

3840-402: Was first demonstrated in space in 2024, an early test envisioned to enhance IoT capabilities. The name "Bluetooth" was proposed in 1997 by Jim Kardach of Intel , one of the founders of the Bluetooth SIG. The name was inspired by a conversation with Sven Mattisson who related Scandinavian history through tales from Frans G. Bengtsson 's The Long Ships , a historical novel about Vikings and

3904-496: Was intended to be a table-top device named the Vosi Symphony, networked with Bluetooth. Through the negotiations with Motorola , Vosi introduced and disclosed its intent to integrate Bluetooth in its devices. In the early 2000s a legal battle ensued between Vosi and Motorola, which indefinitely suspended release of the devices. Later, Motorola implemented it in their devices which initiated the significant propagation of Bluetooth in

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3968-456: Was ported to OpenBSD as well, however OpenBSD later removed it as unmaintained. DragonFly BSD has had NetBSD's Bluetooth implementation since 1.11 (2008). A netgraph -based implementation from FreeBSD has also been available in the tree, possibly disabled until 2014-11-15, and may require more work. The specifications were formalized by the Bluetooth Special Interest Group (SIG) and formally announced on 20 May 1998. In 2014 it had

4032-493: Was that power consumption on cellphone technology at that time was too high to allow viable integration into a notebook and still achieve adequate battery life. Instead, the two companies agreed to integrate Ericsson's short-link technology on both a ThinkPad notebook and an Ericsson phone to accomplish the goal. Since neither IBM ThinkPad notebooks nor Ericsson phones were the market share leaders in their respective markets at that time, Adalio Sanchez and Nils Rydbeck agreed to make

4096-724: Was the only modulation scheme available. Since the introduction of Bluetooth 2.0+EDR, π/4- DQPSK (differential quadrature phase-shift keying) and 8-DPSK modulation may also be used between compatible devices. Devices functioning with GFSK are said to be operating in basic rate (BR) mode, where an instantaneous bit rate of 1   Mbit/s is possible. The term Enhanced Data Rate ( EDR ) is used to describe π/4-DPSK (EDR2) and 8-DPSK (EDR3) schemes, transferring 2 and 3   Mbit/s respectively. In 2019, Apple published an extension called HDR which supports data rates of 4 (HDR4) and 8 (HDR8) Mbit/s using π/4- DQPSK modulation on 4 MHz channels with forward error correction (FEC). Bluetooth

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