Bluetooth Technology-Wireless Communication Systems-Lecture Slides, Slides of Wireless Communication Systems

Download Bluetooth Technology-Wireless Communication Systems-Lecture Slides and more Slides Wireless Communication Systems in PDF only on Docsity! Outline • What is Bluetooth? • Transmission Capabilities • Application Areas • Comparison with Other Wireless Technologies • Bluetooth Technology Specifications • Network Topology of Bluetooth • Piconet / Scatternet • Logical Channels • Connection Management • Error Correction / Flow Control Mechanisms • Bluetooth Target Markets 2 docsity.com What is Bluetooth? • Bluetooth is a short-range wireless network technology operating in the 2.4 GHz frequency band originally intended to replace the cable(s) connecting portable and/or fixed electronic devices. • such a network is also sometimes called a PAN (Personal Area Network). • part of IEEE802.15.1 WPAN standard. • Bluetooth – also the nickname of Harald Blaatand (Jelling, AD 940-981), King of Denmark and Norway. • The concept was first patented by Ericsson. Currently the Bluetooth trade mark is owned by the Bluetooth SIG (Special Interest Group), a consortium of companies having stake in Bluetooth. • Key features are robustness, low power, and low cost. 3 docsity.com Comparison with other wireless technologies • 802.11 • has higher bit rate compared to Bluetooth but has higher power consumption. Basically it is a LAN technology so not a direct competitor for Bluetooth. • IrDA • low cost but require Line of sight. Only point to point networking. • HomeRF • competing technology but current Bluetooth is better positioned in market. 6 docsity.com Bluetooth Technology Specifications • operates in the 2.4 GHz ISM band (similar to 802.11). • uses Gaussian Frequency Shift Keying modulation scheme. • data is transmitted in packets during time slots which are of fixed duration. • uses Quick Frequency Hoping Packet Switched Protocol to achieve noise immunity (79 hops, 1 MHz each). • connections can be made up to 10m (power level: 0 dBm) or extended up to 100m (power level: 20 dBm). • maximum speed supported in version 1 is 1 Mbps. • each transceiver has a unique 48 bit address. • full duplex communication is supported through time division duplexing (TDD). 7 docsity.com Network Topology of Bluetooth 8 Master Slave single slave piconet multi slave piconet scatternet consisting of three piconets docsity.com Logical Channels • Five logical channels in Bluetooth to carry different types of payload traffic: • Link control (LC) • used to manage the flow of packets over the link interface. • Link manager (LM) • transports link management information between participating stations. • User asynchronous (UA) • carries asynchronous user data. • User isochronous (UI) • carries isochronous user data. • User synchronous (US) • carries synchronous user data. 11 docsity.com Connection Management • Standby • waiting to join a piconet. • Inquire • ask about radios to connect to. • Page • connect to a specific radio. • Connected • actively on a piconet (master or slave). • Park/Hold • low power connected states. 12 Inquiry Page ConnectedTransmit data Ttypical=0.6s Ttypical=2s HoldPark Ttypical=2 ms Ttypical=2 ms Low Power States Active States Standby Connecting States Unconnected Standby docsity.com Error Correction / Flow Control Error Correction • 1/3 rate FEC. • 2/3 rate FEC. • ARQ. Flow Control • FIFO queues at Tx and Rx. • if Rx queue is full the flow control bit is set in the header of the next packet sent. • The Tx freezes its FIFO queue till the bit is reset. 13 docsity.com