Bluetooth looks to UWB for bandwidth

The Bluetooth Special Interest Group is set to use UWB technology to create fast networks that will work with current Bluetooth products.

The group is 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 metres. Promoters envisage 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 metres or fewer, is deployed primarily on mobile phones and headsets. 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, predicted on Techworld back in 2003, by Bluetooth SIG marketing manager, Anders Edlund, would bring the underlying MAC and physical 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 of this year, and has FCC approval to sell products in the US. They will offer speeds up to about 480Mbit/s over two to four metres, with plans to go to 1Gbit/s, 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 and Freescale Semiconductor, said its technology can scale from 100Mbit/s to 2Gbit/s 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 Bluetooth's potential, McCamon said. He envisages Bluetooth as one of several specifications to run on top of UWB, which may also support the wireless IEEE 1394 and USB standards.

McCamon acknowledges Bluetooth 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 much from the meeting of the technologies. Bluetooth is used mostly between mobile phones and headsets, which doesn't require the greater bandwidth of UWB, said Gartner analyst Ken Dulaney. In addition, 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," said Dulaney.

UWB itself faces tall hurdles to a mass market. For example, because of government regulations, its market is essentially limited to the US today (see Can short-range UWB cross the Atlantic?). 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.