The IEEE this week formally ratified the mobile version of the WiMax wireless broadband system as a standard.

Known as 802.16e, the mobile standard now officially extends the already ratified 802.16-2004 - aka 802.11d - specification, which details connections between fixed locations. The 802.16e standard allows a base-station to communicate with a moving device.

The two versions of WiMax are not compatible, but both are expected to be ultimately implemented in dual-mode base-stations, allowing a single antenna to talk to transceivers mounted on the side of buildings and to devices carried by cars, trains and pedestrians.

By the end of 2005, 802.16-2004 and 802.16e should have been merged into a single IEEE document, 802.16e-2005.

The ratified version of 802.16e represents the twelfth draft of the specification developed by the IEEE Task Group preparing the standard. Work originally began in 2002 with a forecast completion timeframe of 18 months. In the end, the process more than twice that.

The ratification of the standard, to be followed by its publication, paves the way for the development official mobile WiMax products. To date, a number of 802.16e-based base-station and client-side systems have come to market, all supporting potentially incompatible draft versions of the specification.

Earlier this month, the IEEE approved the 802.16f amendment to 802.16-2004. The specification adds network management information features to the fixed wireless standard. ®