By placing a $3 billion bet on mobile WiMAX last week, Sprint Nextel became the first U.S. wireless service provider to tip its hand about how it intends to provide customers with the transmission speeds needed for next-generation applications.

Sprint Nextel in April said it would make its 4G technology decision this summer and start deployment by 2008, but the company had tested multiple next-generation technologies, and it wasn't clear which would win.

CEO Gary Forsee said last week the technology would have to meet four criteria: It would have to let Sprint Nextel be first to market; provide economical performance; let the carrier create an environment where it has multiple suppliers for its network; and let it develop, offer and support high-speed services. Mobile WiMAX, or 802.16e, met all four.

Sprint Nextel also announced Intel, Motorola and Samsung will supply network and user gear to support the 4G deployment.

Mobile WiMAX is a fairly new standard, and Sprint Nextel is one of the first large carriers to commit to it. The choice could be viewed as a gamble, but one analyst says the move might fuel WiMAX acceptance worldwide.

"That will create an ecosystem," says Shiv Bakhshi, an analyst with IDC. The position of Motorola and Samsung in the mobile device market, along with Intel's marketing power, will help make this a turning point for WiMAX, he says. "WiMAX was in need of a major player signing on to it," he says, adding that Sprint Nextel's deployment will become a showcase.

The carrier says it will spend $1 billion in 2007 and $1.5 billion to $2 billion in 2008 to build its overlay 4G network, which will run over its existing Code Division Multiple Access/Evolution Data Optimized network.

The network's new capabilities will offer downstream speeds of 2M to 4Mbps, which rival landline DSL and cable services.

Forsee says Sprint Nextel's WiMAX service will be available to 100 million people by 2008.

Before making its decision, the carrier explored many technologies, including Qualcomm's Flarion Flash-OFDM (Orthogonal Frequency Division Multiplexing), but that operates only in the 1.25MHz channel and the majority of Sprint Nextel's spectrum is in the 2.5GHz band, said CTO Barry West. According to a report from the Telecommunications Industry Association, however, Flash-OFDM is expected to catch on with 13 million subscribers worldwide by 2010, when there will be 7.2 million WiMAX users worldwide.