Wireless Personal Area Networks WPANs Raj Jain Professor of CSE Washington University in Saint Louis Saint Louis MO 63130 Jain cse wustl edu These slides are available on line at http www cse wustl edu jain cse574 06 Washington University in St Louis CSE574s 4 1 2006 Raj Jain Overview Wireless Standards Overview Bluetooth Ultra Wideband ZigBee Washington University in St Louis CSE574s 4 2 2006 Raj Jain Wireless Standards Wide Area Network WAN 802 16e Nomadic 802 20 Mobile 802 21 Handoff 802 22 WRAN 2G 2 5G 3G Cellular Metropolitan Area Network MAN 802 16 WiMAX Fixed Wireless MAN Local Area Network LAN 802 11 Wi Fi Personal Area Network PAN 802 15 1 Bluetooth Washington University in St Louis 802 15 3 CSE574s 4 3 802 15 4 ZigBee 2006 Raj Jain Distance vs Data Rate WWAN IEEE 802 22 Range IEEE 802 20 WMAN WiMAX IEEE 802 16 WLAN ZigBee 802 15 4 Bluetooth 802 15 1 WPAN 0 01 Washington University in St Louis 0 1 WiFi 802 11 1 10 Data Rate Mbps CSE574s 4 4 802 15 3 802 15 3a 802 15 3c 100 UWB 1000 2006 Raj Jain Mobility vs Data Rate 802 15 3a UWB Washington University in St Louis CSE574s 4 5 2006 Raj Jain Bluetooth Products Headsets Audio Game Controller Keyboard GPS Printers faxes digital cameras 720 kbps to 10m Competes with infrared which has a range of 1m requires line of sight and has a low data rate Washington University in St Louis CSE574s 4 6 2006 Raj Jain Bluetooth Started with Ericsson s Bluetooth Project in 1994 Named after Danish king Herald Blatand AD 940 981 who was fond of blueberries Radio frequency communication between cell phones over short distances Intel IBM Nokia Toshiba and Ericsson formed Bluetooth SIG in May 1998 Version 1 0A of the specification came out in late 1999 IEEE 802 15 1 approved in early 2002 is based on Bluetooth Key Features Lower Power 10 A in standby 50 mA while transmitting Cheap 5 per device Small 9 mm2 single chips Washington University in St Louis CSE574s 4 7 2006 Raj Jain Bluetooth Details Frequency Range 2402 2480 MHz total 79 MHz band 23 MHz in some countries e g Spain Data Rate 1 Mbps Nominal 720 kbps User Channel Bandwidth 1 MHz Range Up to 10 m can be extended further RF hopping 1600 times s 625 s hop Security Challenge Response Authentication 128b Encryption TX Output Power Class 1 20 dBm Max 0 1W 100m Class 2 4 dBm 2 5 mW Class 3 0 dBm 1mW 10m Ref http www bluetooth com http www bluetooth org http grouper ieee org groups 802 15 index html Washington University in St Louis CSE574s 2006 Raj Jain 4 8 Piconet Piconet is formed by a master and many slaves Up to 7 active slaves Slaves can only transmit when requested by master Up to 255 Parked slaves Active slaves are polled by master for transmission Each station gets a 8 bit parked address 255 parked slaves piconet The parked station can join in 2ms Other stations can join in more time A device can participate in multiple piconets complex schedule Washington University in St Louis CSE574s 4 9 2006 Raj Jain Frequency Hopping Sequences Frequency 1 Frequency 2 Frequency 3 625 s slots Time division duplex TDD Downstream and upstream alternate Master starts in even numbered slots only Slaves start in odd numbered slots only lsb of the clock indicates even or odd Slaves can transmit in one slot right after receiving a packet from master Packets 1 slot 3 slot or 5 slots long The frequency hop is skipped during a packet Washington University in St Louis CSE574s 4 10 2006 Raj Jain Bluetooth Packet Format Access Baseband Link Data Code Control Header Payload 72b 54b 0 2745b Packets can be up to five slots long 2745 bits Access codes Channel access code identifies the piconet Device access code for paging requests and response Inquiry access code to discover units Header member address 3b type code 4b flow control ack nack 1b sequence number and header error check 8b 8b Header is encoded using 1 3 rate FEC resulting in 54b Synchronous traffic has periodic reserved slots Other slots can be allocated for asynchronous traffic Washington University in St Louis CSE574s 4 11 2006 Raj Jain Bluetooth Operational States Standby Disconnected Inquiry Connecting Active Low Power Washington University in St Louis Page Transmit Park Connected Sniff CSE574s 4 12 Hold 2006 Raj Jain Bluetooth Operational States Cont Standby Initial state Inquiry Master sends an inquiry packet Slaves scan for inquiries and respond with their address and clock after a random delay CSMA CA Page Master in page state invites devices to join the piconet Page message is sent in 3 consecutive slots 3 frequencies Slave enters page response state and sends page response including its device access code Master informs slave about its clock and address so that slave can participate in piconet Slave computes the clock offset Connected A short 3 bit logical address is assigned Transmit Washington University in St Louis CSE574s 4 13 2006 Raj Jain Energy Management in Bluetooth Three inactive states Hold No ACL SCO continues Node can do something else scan page inquire Sniff Low power mode Slave listens only after fixed sniff intervals Park Very Low power mode Gives up its 3 bit active member address and gets an 8 bit parked member address Packets for parked stations are broadcast to 3 bit zero address Sniff Washington University in St Louis Park CSE574s 4 14 2006 Raj Jain Power per MB Washington University in St Louis CSE574s 4 15 2006 Raj Jain Bluetooth Protocol Stack Application Applications Profiles TCS RFCOMM Middleware Audio SDP Control L2CAP Link Manager Baseband Transport RF RF Frequency hopping GFSK modulation Baseband Frequency hop selection connection MAC Washington University in St Louis CSE574s 4 16 2006 Raj Jain Baseband Layer Each device has a 48 bit IEEE MAC address 3 parts Lower address part LAP 24 bits Upper address part UAP 8 bits Non significant address part NAP 16 bits UAP NAP Organizationally Unique Identifier OUI from IEEE LAP is used in identifying the piconet and other operations Clock runs at 3200 cycles sec or 312 5 s twice the hop rate Upper Address Part Non sig Address Part Lower Address Part 8b 16b 24b Washington University in St Louis CSE574s 4 17 2006 Raj Jain Bluetooth Protocol Stack Cont Logical Link Control and Adaptation Protocol L2CAP Protocol multiplexing Segmentation and reassembly Controls peak bandwidth latency and delay variation Host Controller Interface RFCOMM Layer Presents a virtual serial port Sets up a connection to another RFCOMM Service Discovery Protocol SDP Each device has one SDP which acts as
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