Wireless USB
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Wireless USB is a short-range, high-bandwidth wireless extension to USB that combines the speed and ease-of-use of USB 2.0 with the convenience of wireless technology. Wireless USB is sometimes abbreviated as "WUSB", although the USB Implementers Forum discourages this practice and instead prefers to call the technology "Certified Wireless USB" to differentiate it from competitors (see below, "Competitors"). Wireless USB is based on the WiMedia Alliance's Ultra-WideBand (UWB) common radio platform, which is capable of sending 480 Mbit/s at distances up to 3 meters and 110 Mbit/s at up to 10 meters. It was designed to operate in the 3.1 to 10.6 GHz frequency range, although local regulatory policies may restrict the legal operating range for any given country.
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[edit] Uses
WUSB will be used in devices that are now connected via regular USB cables, such as game controllers, printers, scanners, digital cameras, MP3 players, hard disks and flash drives, but it is also suitable for transferring parallel video streams.
[edit] Development
The Wireless USB Promoter Group was formed in February 2004 to define the Wireless USB specification. The group consists of Agere Systems, Hewlett-Packard, Intel, Microsoft, NEC Corporation, Philips and Samsung.
In May 2005, the Wireless USB Promoter Group announced the completion of the Wireless USB specification. Companies like Ellisys and LeCroy are supplying development support tools to facilitate early introduction of the technology.
In June 2006, USB Implementers Forum (USB-IF) offered the first five-way, multi-vendor interoperable demonstration of Certified Wireless USB. A laptop with an Intel host adapter using an Alereon PHY was used to transfer high definition video from a Philips wireless semiconductor solution with a Realtek PHY, all using Microsoft Windows XP drivers developed for Wireless USB.
In October 2006 the FCC approved the first complete Host Wire Adapter (HWA) and Device Wire Adapter (DWA) wireless USB solution from WiQuest Communications for both outdoor and indoor use.
[edit] Host Wire Adapters, Device Wire Adapters, and Dual-Role Devices
The WUSB architecture allows up to 127 devices to connect directly to a host. Because there are no wires or ports, there is no longer a need for hubs.
However, to facilitate the migration from wired to wireless, WUSB introduced a new Device Wire Adapter (DWA) class. Sometimes referred to as a "WUSB hub", a DWA allows existing USB2 devices to be used wirelessly with a WUSB host.
WUSB host capability can be added to existing PCs through the use of a Host Wire Adapter (HWA). The HWA is a USB2 device that attachs externally to a desktop or laptop's USB port or internally to a laptop's MiniCard interface.
WUSB also supports Dual-Role Devices (DRDs), which in addition to being a WUSB device, can function as a host with limited capabilities. For example, a digital camera could act as a device when connected to a computer and as a host when transferring pictures directly to a printer.
[edit] Relation to Ultra-wideband (UWB)
A common source of confusion is about the relationship between WUSB, WiMedia, and UWB. The UWB and WUSB technologies are not the same, and the terms WUSB and UWB are not synonymous.
UWB is a radio platform promulgated by the WiMedia Alliance. WUSB is a protocol promulgated by the USB-IF that uses WiMedia's UWB radio platform. Other protocols that have announced their intention to use WiMedia's UWB radio platform include Bluetooth, Wireless 1394, and WiNet.
[edit] Competitors: Certified Wireless USB vs WirelessUSB™
[edit] WirelessUSB
"WirelessUSB" by Cypress Semiconductor is not related to "Certified Wireless USB".
Cypress's "WirelessUSB" is a protocol that uses the 2.4 GHz band with a range from 10 meters (at max 1 Mbit/s) to 50 meters (at max 62.5 kbit/s) and is designed for Human Interface Devices (HIDs), with current offerings from companies such as Belkin, Logitech, and Virtual Ink.
[edit] UWB
Other forms of Wireless USB such as those to be offered on the competing UWB technology based on Freescale pulse method are also not approved by the IEEE. The same is also true for other RF based Wire replacement systems which can carry USB. The result is that the name 'Certified Wireless USB' had to be adopted to allow consumers to identify which products would be adherent to the standard and would support the correct protocol and data rates.
[edit] References
[edit] See also
- Bluetooth – IEEE 802.15.1
- Wibree
- WirelessHD
- ZigBee – IEEE 802.15.4
