14-03-2010, 07:25 AM
WirelessUSB.ppt (Size: 941.5 KB / Downloads: 1,042)
Wireless Universal Serial Bus
Submitted By:
Christopher Hanudel
Outline
Wired Universal Serial Bus (USB)
Overview of Wireless USB (wUSB)
History/Vision
Features
How wUSB Works
Design
Security
Issues/Limitations
Current Implementations
Future/Conclusion
Wired USB
Overview
Plug/Play standard for peripheral devices
Standardized by the USB Implementers Forum
Technical Details
Host/Slave Connection
PC (host) manages all transfers; peripherals (slave) just responds
Supports 127 slaves per host
Physical Connection
Four wire connection
Two wires for power (+5 and GND)
Two wires (twisted pair) for synchronous serial data
Computer supplies power (up to 500 mA)
Technical Details (Cont.)
Data Rates
Low Speed: 1.5 Mbps (Keyboards, mice, etc.)
Full Speed: 12 Mbps (USB1.1 max speed)
Hi-Speed: 480 Mbps (USB2.0 max speed)
Reasons For Wireless USB
Wired Issues
Wires are restrictive
Multiple wires can be a hassle
Wires slower than wireless solutions
Current wireless solutions inadequate
Bluetooth
Bandwidth of 3 Mbps not enough for higher demand applications (Video, HDTV, Monitor)
WiFi
Expensive
Too much power usage for mobile devices
Wireless USB Overview
Overview
Has evolved as companies figured out standards
Based on Ultra-Wideband (UWB) RF technology
UWB is a technology for transmitting data over a large bandwidth (>500 MHz)
History of Ultra-Wideband (UWB)
Late 1800s: Started with Spark Gap radio for transmitting Morse Code
1924: Spark Gap forbidden due to disruptive nature to narrowband carrier radios
1960s “ 1999s: Better test equipment promoted research of UWB for radar and communications
History of Ultra-Wideband (cont.)
April 2002: FCC issued UWB Regulations
Permitted marketing and operation of new products
Limited power and freq range
2002: Two standards emerge
Orthogonal Frequency Division Multiplexing (OFDM) UWB
WiMedia Alliance & Intel
Direct Sequence (DS) UWB
UWB Forum & Freescale
2006: DS-UWB loses support & OFDM-UWB wins
Freescale left UWB Forum; became quiet
Many companies dropped Freescale chips
Freescale trying proprietary Cable-Free USB
2007: Products begin to hit the market
Goals of Intel OFDM-UWB Wireless USB Standard
Wireless version of USB; same features, speeds
Interoperable across three major platforms
Consumer Electronic devices (digital video/audio)
Mobile devices (cellular phones, PDA)
Personal Computing (laptop, PC, printer, peripherals)
High bandwidth to support demanding data transfer (High Definition, Monitors)
Mobile friendly
Low power usage
Inexpensive costs
Small physical implementation
High level of security
Next gen Wireless Personal Area Network (WPAN)