Alereon is releasing the a wireless USB chip that conforms to the WiMedia standard. The AL4000 from the Austin, Texas-based chip designer, will reportedly be the first “wireless usb” chipset to reach the consumer market. The first device to use it is expected to be a wireless USB hub that communicates wirelessly to a dongle on the computer.
Belkin has a similar hub using chips from Wisair of Israel, but it uses a different standard — “Cable-Free USB“. The two standards are incompatible.
The “Wireless USB” standard — as specified by WiMedia — utilizes an extended frequency band through 5 GHz and up to 10 GHz.
In theory, UWB can reach speeds of up to 480 megabits per second, equivalent to USB 2.0 cables, at distances up to 10 feet, but Alereon spokesman Mike Krell said first-generation devices are not that fast. Alereon’s first chip, the AL4000, utilizes 3.1Ghz to 4.7GHz and not the extended frequencies and is therefore slower. A new chip, Alereon’s AL5000, uses frequencies up to 10.6 GHz. It is expected to show up in external hard drives and cameras this year.
Two incompatible UWB schemes were competing for the IEEE’s blessing; one using DS (direct sequence) and notch filtering of the 5 GHz band, and one using OFDM (orthogonal frequency division multiplexing) using more frequencies below 10 GHz. Supporters of each approach — the UWB Forum for DS-UWB and the WiMedia Alliance for OFDM-UWB — tried to get the IEEE to adopt their technologies as an IEEE standard, but failed. So they went out on their own.
Motorola spinoff Freescale Semiconductor championed the incompatible (”Cable-Free USB”) which skipped the 5 GHz band. WiMedia and the MultiBand OFDM Alliance merged in 2005. Now it looks like “WiMedia’s Wireless USB” — as supported by Alereon — will win the battle for a defacto UWB standard. WiMedia’s UWB “standard” has won wide industry support and last year the Bluetooth Special Interest Group voted to support WiMedia’s UWB flavor, boosting it still further.
Another competitor, Realtek Semiconductor of Taiwan, announced in May a chip that uses frequencies reaching into the 7.3 GHz to 9 GHz band that is legal or expected to be legal all over the world.
Related UWB articles on DailyWireless include; Wireless USB Gets a Standard, Motorola Buys Gbps Wireless HomeNet, Wireless HDMI, UWB at CES, UWB Goes Global, UltraWideband: All Together Now? and Cable-Free Vrs Wireless USB.
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