Bluetooth looks to UWB for bandwidth
- — 06 May, 2005 03:58
The body that oversees the Bluetooth personal-area wireless specification wants to take advantage of emerging UWB (ultrawideband) technology to create fast networks that are backward-compatible with current Bluetooth products.
The Bluetooth Special Interest Group (SIG) was set to announce on Wednesday its intention to work with the WiMedia Alliance and the UWB Forum, which are promoting two different UWB technologies. UWB is designed to deliver much greater bandwidth than a Wi-Fi wireless LAN, but over a distance of only a few meters. Promoters envision it as an interconnect for consumer electronics applications such as home entertainment networks that support streaming video.
Bluetooth, which delivers no more than a few megabits per second over a typical range of 10 meters or less, is deployed primarily on mobile phones and headsets and to a lesser degree in other devices such as wireless keyboards and mice. The Bluetooth SIG industry group sees piggy-backing on UWB as a way to speed up Bluetooth for future products such as mobile phones that can capture large video files or store large amounts of digital music. It could be used to transfer megabits of music files from a PC to a phone, for example, said Michael Foley, executive director of the Bluetooth SIG.
The plan would bring the underlying MAC (media access control) and phy (physical interface) layers of UWB together with higher level components from Bluetooth. The idea is to take Bluetooth technology forward while giving customers a relatively well-known interface to the new, faster type of network.
The Institute of Electrical and Electronics Engineers (IEEE) working group for the UWB standard, IEEE 802.15.3a, has been deadlocked between two technical approaches backed by the WiMedia Alliance and UWB Forum. Companies backing both kinds of UWB are moving ahead to market.
The WiMedia Alliance, which includes Intel, Sony, Microsoft and Hewlett-Packard, expects its members to begin shipping UWB products by the fourth-quarter holiday season of this year. They will offer speeds up to about 480M bps (bits per second) over two to four meters, with plans to go to 1G bps, according to Stephen Wood, president of the WiMedia Alliance. The alliance looks forward to working with the Bluetooth SIG, he said.
The UWB Forum, which counts among its members Motorola Inc. and Freescale Semiconductor Inc., says its technology can scale from 100M bps to 2G bps with a similar range. The forum hopes to set specifications for interoperability testing in the second half of this year, according to Mike McCamon, executive director of the group.
The UWB Forum is eager to explore ways to take advantage of Bluetooth, McCamon said. He envisions Bluetooth as one of several specifications to run on top of UWB, which may also support the wireless IEEE 1394 and USB (universal serial bus) standards.
McCamon, a former executive director of the Bluetooth SIG, acknowledges Bluetooth has a long way to go to become a mainstream consumer technology -- partly because the Bluetooth SIG has never had products tested for interoperability -- but nevertheless it has a head start on UWB. The process from the first product shipment to becoming a mainstream product usually takes ten years, in McCamon's view.
"The advantage that Bluetooth has right now is that they're five years further down that road than we are," McCamon said.
One longtime observer of Bluetooth does not expect great synergies to come out of the meeting of the technologies. Bluetooth is used mostly between mobile phones and headsets, an application that doesn't require the greater bandwidth of UWB, said Gartner analyst Ken Dulaney. In addition, largely because of the lack of interoperability testing, Bluetooth's track record is not an enviable one, he said.
"While [Bluetooth] may have brand recognition, the brand doesn't stand for much except a confusing user interface and at least a few hours of your time to get two things connected," Dulaney wrote in an e-mail interview.
UWB itself faces tall hurdles to a mass market. For example, because of government regulations, its market is essentially limited to the U.S. today. And the use of Bluetooth on top of UWB would not resolve or mask the incompatibility between the two technical approaches, according to UWB Forum's McCamon. The struggle between the two sides continues.
"It's been really ugly. ... In fact, it's been excessively unpleasant," McCamon said.