Sprint Nextel announced Tuesday its plans to roll out a nationwide 4G wireless network based on the mobile WiMAX specification.

The carrier appears to be the first wireless service provider in the United States to firmly plant its feet in the ground and state exactly how it will bring higher data transmission speeds to its mobile customers nationwide.

Sprint Nextel’s announcement isn’t unexpected. Len Lauer, COO at Sprint Nextel, said in April that Sprint would make its 4G technology decision this summer and start deploying it by 2008. But since Sprint Nextel had tested multiple next generation technologies, it wasn’t clear which would emerge as the winner.

In selecting its 4G technology Gary Forsee, CEO at Sprint Nextel said the technology had to meet four criteria, which are: Allow Sprint to be first to market, provide economical performance, allow Sprint to create an ecosystem, and provide a compelling business model.

Mobile WiMAX met all four criteria, he says.

Clearly, Sprint Nextel is betting its future on the technology. 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 CDMA/EV-DO network.

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

Before making its decision to go with mobile WiMAX, Sprint Nextel’s chief technology officer Barry West says the carrier explored many technologies including Qualcomm’s Flarion Flash-OFMD, but it only operates in the 1.25MHz channel and the majority of Sprint’s spectrum is in the 2.5GHz band.

But According to a report from the Telecommunications Industry Association Flash-OFDM is expected to catch on with 13 million subscribers worldwide by 2010. The same report predicts that there will be 7.2 million WiMAX users worldwide by 2010.

"We see many of these emerging wireless standards doing well, although by selecting the Intel 802.16e strategy Sprint has made a rather big statement," says Larry Swasey, senior analyst at consulting firm Visant Strategies. "Many of the other standards that were trialed and not chosen are in commercial deployments elsewhere and still have a large audience of operators, both fixed and mobile, that could utilize these technologies for a myriad of purposes and in different frequencies."