Wi-Fi set to get lift from Bluetooth

Bluetooth is about to get a big boost in data rate and in some cases distance.

On 21 April, the group overseeing the Bluetooth specification will launch a version that can use an available 802.11 Wi-Fi radio for the wireless connection. A 3.0 Bluetooth stack would be able to switch from the standard low-power, short-range Bluetooth radio to an 802.11abg radio. With 11g and 11a being now far more common, that would mean throughput in the 20Mbit/s-24Mbit/s range in either the 2.4GHz or 5GHz bands, compared to a maximum today of up to 3Mbit/s in 2.4GHz for Bluetooth 2.1 with Enhanced Data Rate.

Most users would probably see a jump in Bluetooth range also. Class 2 radios, which are most commonly found in headsets, handhelds and other consumer devices, today can reach about 30 feet. Class 3 radios, for specialised industrial use, can reach 300 feet, which is comparable to Wi-Fi ranges.

The new parts of the specification, dubbed the Generic Alternate MAC/PHY will be implemented in code by software developers, adding to the Bluetooth software stack, which today is used in conjunction with a low-power Bluetooth radio. Some existing products, such a notebook PC, might be able to use the new capability, via a software update.

Another new feature in 3.0 is Enhanced Power Control, which is intended to cut the number of disconnects that can be caused by movement such as placing a handset or other Bluetooth device into a pocket or purse.

The move is part of a shift by the Bluetooth Special Interest Group (SIG), to make use of alternative underlying physical and media access control layers to improve throughput. The Wi-Fi project was announced just over a year ago. The goal was to enable the use of Wi-Fi when needed for large-scale data uploads or downloads.

Earlier the SIG had started working on an ultra-wideband (UWB) version of its spec, with the WiMedia Alliance. That project has taken a lower priority as UWB struggles for wider acceptance. The Alliance is disbanding after it completes a handoff its own UWB work to the Bluetooth SIG and to the Wireless USB Implementers Forum.

The Bluetooth SIG has lined up a range of chipmakers who intended to create single chips that integrate both Wi-Fi and Bluetooth. Those partners will be announced at the 3.0 launch later this month, when SIG members will go into more details about power requirements, application profiles, and the like.