Bluetooth

Introduction to BluetoothBluetoothis the name given to a new technology standard usingshort-range radio links, intended to replace the cable(s) connecting portable and/or fixed electronic devices. Bluetooth radios operate in the unlicensed ISM band at 2.4 Gigahertz using 79 channels between 2.402 GHz to 2.480 GHz (23 channels in some countries) (Bluetooth Protocol Architecture, White Paper). The range for Bluetooth communication is 0-30 feet (10 meters) with a power consumption of 0dBm (1mW). This distance can be increased to 100 meters by amplifying the power to 20dBm. The Bluetooth radio system is optimized for mobility. Its key features are robustness, low complexity, low power and low cost. The technology also offers wireless access to LANs, PSTN, the mobile phone network and the Internet for a host of home appliances and portable handheld interfaces. [1][2]The immediate need forBluetoothcame from the desire to connect peripherals and devices without cables. The available technology-IrDA OBEX (IR Data Association Object Exchange Protocol) is based in IR links that are limited to line of sight connections.Bluetooth integrationis further fueled by the demand for mobile and wireless access to LANs, Internet over mobile and other existing networks, where the backbone is wired but the interface is free to move.[1] It was originally conceived as a wireless alternative toRS-232data cables. [3]Bluetooth is managed by theBluetooth Special Interest Group(SIG), TheIEEE standardized Bluetooth asIEEE 802.15.1, but no longer maintains the standard. The Bluetooth SIG oversees development of the specification, manages the qualification program, and protects the trademarks. [3][4]A manufacturer must make a device meetBluetooth SIG standardsto market it as a Bluetooth device. [5]To use Bluetooth wireless technology, a device must be able to interpret certain Bluetooth profiles, which 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 parametrize and to control the communication from 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. [6][7]

History of BluetoothIn 1994, the L. M. Ericsson Company became interested in connecting its mobile phones to other devices without cables. Together with four other companies (IBM, Intel, Nokia and Toshiba), it formed a SIG (Special Interest Group) in 1998 to develop a wireless standard for interconnecting computing and communication devices and accessories using short-range, low-power and inexpensive wireless radios. The project was named Bluetooth. [8]It was originally focused on expanding on an original idea of creating a standard for a wireless headset. Today it has over 27,000 members and its main mission is the upkeep of a technology standard for the wireless transfer of data over short distances. [9]The first Bluetooth-enabled mobile phone,the Ericsson T36, was brought to market in 2000. The following year sawthe first printer using Bluetooth hit the market in 2001. Mouse and keyboard followed the next year. By 2003, the focus turned towards music with the launch of the first MP3 player and the first stereo headset by the 2004. Bluetooth hit thewearable gadgetry waveearly with Bluetooth chips implanted within watches and sunglasses in 2006. By 2012,annual shipments of Bluetooth-enabled products reached 2 billion worldwide. At the end of 2014, membership in Bluetooth SIGS had reached 24,000 members and hit 90 percent penetration into the mobile phone market. [9][10]

Bluetooth Architecture, Communication and ConnectionThe Bluetooth technology is divided into two specifications: the core and the profile specifications. The core specification discusses how the technology works, while the profile specification focuses on how to build interoperating devices using the core technologies. [11] The Bluetooth Core Specification provides for the connection of two or more piconets to form ascatternet, in which certain devices simultaneously play the master role in one piconet and the slave role in another. [12] Bluetooth communicationoccurs between a master radio and a slave radio. Bluetooth radios are symmetric in that the same device may operate as a master and also the slave. Each radio has a 48-bit unique device address (BD_ADDR) that is fixed. Two or more radio devices together form ad-hoc networks called piconets. [13]A master 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. A master is the only one that may initiate a Bluetooth communication link. Slaves are not allowed to talk to each other directly. All communication occurs within the slave and the master. 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 masteras initiator of the connectionbut may subsequently operate as slave).; however, a "master/slave swap" function allows the roles to be reversed. (A device can only be a master in one piconet though.) [11][12][13]The reason for the master/slave design is that the designers intended to facilitate the implementation of complete Bluetooth chips for under $5. The consequence of this decision is that the slaves are fairly dumb, basically just doing whatever the master tells them to do. At its heart, piconet is a centralized Time Division Multiplexing (TDM) system, with the master controlling the clock and determining which device gets to communicate in which time slot. [8]

Advantage of Bluetooth vs Other Wireless ConnectionsThe purpose of Bluetooth is to avoid the problems that come with both infrared and cable synchronizing systems. One major advantage of Bluetooth is its simplicity of use. Anyone can figure out how to set up a connection and sync two devices with ease. Moreover, the technology is free to use and requires no charges to be paid to any service provider. There are four important features to Bluetooth: It is Wireless; it is inexpensive, prices are coming down; no static at all; and it happens automatically. [14][15]Bluetooth could also be used in home networking applications. With increasing numbers of homes having multiple PCs, the need for networks that are simple to install and maintain, is growing. Bluetooth's main strength is its ability to simultaneously handle both data and voice transmissions, allowing such innovative solutions as a mobile hands-free headset for voice calls, print to fax capability, and automatically synchronizing PDA, laptop, and cell phone address book applications. [2]References:1. Bluetooth Technology. Gc. 18 February 20132. Bluetooth Introduction. Gc. 18 February 2013 3. Newton, Harold. (2007).Newtons telecom dictionary.New York: Flatiron Publishing.4. "Bluetooth.org". Bluetooth.org. 3 May2011.5. "Brand Enforcement Program". Bluetooth.org. 2 November2013.6. "Profiles Overview". Bluetooth.com. 3 June2013.7. Ian, Paul."Wi-Fi Direct vs. Bluetooth 4.0: A Battle for Supremacy". PC World. 27 December2013.8. Tanenbaum, Andrew. (2012). Computer Networks3 5e P.3209. The Short History of Bluetooth change the world. Hector Ruiz. 01 November 201510. Evolution of Technology: Bluetooth, the once and future king. Steve Brachmann. 10 May 201511. Bluetooth Specification, Bluetooth SIG at http://www.bluetooth.com/. 12. Bluetooth Architecture. Gc. 18 February 201313. Bluetooth Architecture Overview (PDF). James Kardach Mobile Computing Group, Intel Corporation 14. Shaw, Russel. (2003). Wireless Networking Made Easy. pp. 22-2515. Advantages and Disadvantages of Bluetooth Technology. Rahul Thadani. 5 February 2016