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Presented at the First Workshop on Computer Architecture Evaluation Using Commercial Workloads (held with HPCA-4, Las Vegas, February 1, 1998). 3G :The Next Generation. Sridhar Rajagopal. Contributions from: Edouard Bugnion, Jack Lo, and Parthas Ranganathan. Outline . 3G Wireless
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Presented at theFirst Workshop on Computer Architecture Evaluation Using Commercial Workloads (held with HPCA-4, Las Vegas, February 1, 1998) 3G :The Next Generation Sridhar Rajagopal Contributions from: Edouard Bugnion, Jack Lo, and Parthas Ranganathan
Outline • 3G Wireless • The World of Mobile Multimedia • Introduction - 3G Standards • Implementation Issues • My idea of the future
3G Wireless • 1G • Analog voice communications (AMPS) • 2G • Digital voice • Data Services • Low to Medium rate (9.6 kbps) • DAMPS, GSM, IS-95 • 3G • Integrate Multimedia Services • High Data Rates • Adaptability of mobile device to the environment. • Unite different communication platforms • Different standards • Different means of communication
The World of Mobile Multimedia • Take Part in a Video Conference from a Remote Location • Share Information to Feel Closer • Get What You Want When You Want It! • Explore your Intellectual Curiosity in a Mobile Environment • Various Security Functions • Electronic Account Settlement in a Mobile Environment • http://www.nttdocomo.com/….
Modes Of Operation • Packet Data Services • Real Time Services • Mixed Services • Supports variable rates of transmission • Different QoS requirements • Different rates for different environments • 2 Mbps : Indoor • 384 kbps : Pedestrian • 144 kbps : Vehicular
Adaptability of the Mobile • Communication : Anytime, Anywhere…….. • A ‘Single Appliance’ that can work at • Indoor : Wireless /(Wired Ethernet) • Outdoor : Wireless • Home : Cable Modem / DSL / Wireless • REASON for Adaptability : driven by COST • Wires are here to stay!
United we Stand • Different 2G standards • GSM, IS-95. • Work in the African Jungles, the Sahara Desert, Antartica? • Harmonization : • UMTS/IMT-2000 : ETSI,ARIB,3GPP,ANSI,ITU • Goal : • Global Communication
Packet Data Voice Circuit Data Application Services Application OSI Signaling Layers TCP UDP Services 3-7 High Speed IP Circuit Network Layer Services PPP Link Access LAC Protocol Null LAC Control (LAC) OSI MAC Medium Layer Control Best Effort Delivery Access 2 States (RLP) Control (MAC) QoS Control Multiplexing OSI Layer Physical Layer 1 3G Layer Structure http://www.itu.int/imt/2-radio-dev/index.html
Wireless Network Configuration http://www1a.mesh.ne.jp/...
3G Standards - Radio Access Network • Improved Capacity (3 dB) • Coverage & Link Budget Improvements • Power, the Common Resource • Adjust Power to limit interference & get QoS. • Multiple Parallel Services on a single connection • OVSF • Link Improvements • Multiuser Detection, Transmit Diversity, Adaptive Antennas…. • Asynchronous Base Station operation
3G Standards - Radio Access Network • Interfrequency Handover • Hierarchical Cell Structure (HCS) [ Macro & Micro Overlap] • ‘Hot Spots’ • SCR’s • Support for Adaptive Antenna Arrays • TDD Mode
The Air Interface • 5 MHz Bandwidth • Resolve more multipaths, capacity • Basic Chip Rate • 4.096 Mcps • Basic Frame Length • 10ms
Transport Channels • Unidirectional • Dedicated / Common • Broadcast Control (DL) • Forward Access (DL) • Paging (DL) • Random Access (UL) • Dedicated (UL/DL)
DPCCH DPCCH DPCCH DPCCH DPCCH DPCCH DPDCH DPDCH DPDCH DPDCH Pilot Pilot TPC TPC Data2 Data2 FDD FDD TFCI TFCI Data1 Data1 N N bits bits N N bits bits N N bits bits DOWNLINK DOWNLINK N N bits bits N N bits bits pilot pilot data2 data2 TPC TPC TFCI TFCI data1 data1 k T = 2560 chips, 10*2 bits (k=0..7) slot Data DPDCH N bits data FDD UPLINK FBI TPC Pilot TFCI DPCCH N bits N bits N bits N bits FBI TPC pilot TFCI k T = 2560 chips, 10*2 bits (k= 0 . . 6) slot Channel Structure 1 Frame = 16 slots
Spreading and Modulation • QPSK Modulated • Scrambling Code Length = 1 Frame (40960 chips) • Truncated Complex Gold Code (218 -1 ) for Scrambling • Uplink • Users distinguished by Scrambling Codes • Downlink • Users distinguished by their Walsh codes • Scrambling code to distinguish cells.
Channel Coding • Rate 1/3 Convolutional Code • Low Delay , Moderate Error (10-3) • Concatenated Rate 1/3 + Outer RS + Interleaving • High Quality (10-6 BER) • Turbo Codes • High Rate, High Quality
Random Access Channel • For Acquisition of a Dedicated Channel • MS selects spreading codes for preamble/message • MS selects spreading factor for message • Randomly selects signature & access slot for burst • MS - Closed Loop Power Control • Transmits • If no ACK, repeat!
Implementation Issues • ‘Single Appliance’ • How should the hardware look? • Current Application • Nokia 9110 Communicator • Embedded AMD 486 processor • 2 Mb user data • 8 Mb memory • GEOS Operating System (ver 3.0) • Dimensions: 158 x 56 x 27 mm • Weight: 253 g • Data speed :14,400 bps
Implementation Issues • Various applications have different needs • Desired Bandwidth • Error Rate • Security • All applications can use the same memory. • Make it Software- reconfigurable. • MIT Oxygen Project : • Microchip wiring that can be automatically reprogrammed for different tasks. • Software controlled Logic Operations • Software controlled wire routing.
Implementation Issues • Adaptation to different environments • Seamless handover • Reconfigurability issues • WAP (Wireless Application Protocol) Support • Internet services on Mobile appliances. • Directions : • Dynamically Reconfigurable FPGA’s • mNIC
My Idea of the Wireless Future • A laptop 5 times lighter • Have a mobile phone attached • Ear plug for hands-free talking • Size adjustable • Low Power • Can be attached in front of you • Wireless access, anytime, anywhere • Can be folded & kept in your pocket! • Low COST! • Reusable Paper Printer at the Bottom