22-09-2016, 10:44 AM
1455625800-WirelessUSB.ppt (Size: 1.14 MB / Downloads: 4)
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)
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