Mobile WiMax gets green light

The standard, called 802.16e, was finalized two months ago, but it was formally ratified on Wednesday by the Institute of Electrical and Electronics Engineers. Finalizing the standards process is an important milestone in the life of a technology and should help spur adoption.

"Carriers don't like their futures dependent on a single vendor," said Paul Sergeant, director of marketing for WiMax at Motorola. "They may only buy from one vendor, but they want a choice. So it's very important to have a standard that gives them the security to know they can go to another supplier and the equipment will interoperate."

WiMax is considered a promising next-generation wireless technology because it supports high data rates and has a long transmission reach. The technology supports peak data speeds of around 20 megabits per second with average user data rates between 1 mbps and 4 mbps, Sergeant said. Transmission distances range from a few hundred feet in densely populated areas to between one and two miles in suburban areas.

Some WiMax supporters see the technology as a both a complement to cellular telephone networks and a replacement for citywide Wi-Fi. Even though phone companies have spent billions of dollars upgrading their cellular networks, they are still limited in capacity. Today's 3G wireless networks transmit only between 400 kilobits per second and 700 kilobits per second per user.

Cellular still has a longer reach than WiMax, but supporters of WiMax believe that cellular operators could use the technology to augment their networks and provide more capacity for data applications like mobile Web surfing or e-mailing. Sprint Nextel is already testing the technology in its laboratories.

On the other hand, WiMax supporters also see the new technology as a replacement for Wi-Fi, which was originally designed to be used inside offices and homes. Wi-Fi offers comparable data rates, but its radios transmit up to only about 50 feet. This means that when Wi-Fi is used in an outdoor setting to blanket a city, hundreds of access points are needed.

Many cities, such as Philadelphia and San Francisco, have already started working on plans that include using mesh Wi-Fi technology to blanket their cities. One of the things that makes Wi-Fi attractive is that the radios and chipsets that receive the signals are extremely inexpensive. Practically every laptop built today has a Wi-Fi chipset embedded.

But Sergeant believes the new 802.16e standard will do for WiMax what the 802.11 standards have done for Wi-Fi. Intel and Motorola have already announced that they plan to collaborate to speed up adoption of the new standard.

Sergeant predicts that products designed for fixed WiMax applications, such as providing broadband connectivity directly to residential customers, will be available in 2006. In 2007, mobile devices such as PDAs (personal digital assistants) and smart phones will use the standard technology. And by 2008 and 2009, 802.16e chipsets will be manufactured in large volumes, spurring even further adoption.

"WiMax was built for outdoor mobility," Sergeant said. "Wi-Fi wasn't. The challenge we face going forward is getting WiMax into more devices; 2006 and 2007 will be the introduction and build-out years, and products will start shipping in volume in 2008 and 2009."