The end of WiMAX in the United States is nigh.

Sprint is moving ahead with plans to shut down its WiMAX network by the end of next year. The wireless provider continues to replace WiMAX with LTE, the 4G standard to which most operators have gravitated. Sprint decided on WiMAX first through a partnership with Clearwire Corp., and then through the acquisition of Clearwire.

At the time of that purchase in mid-2013, Clearwire had deployed WiMAX on about 17,000 cell towers and, at the same time, was deploying 4G LTE technology on about 5,000 of those sites, Sprint said. That project was finished but the overall move to 4G does not.

“We plan to expand the … 4G LTE deployment to approximately 5,000 more legacy Clearwire sites,” Sprint wrote in its recent annual report, filed with the Securities and Exchange Commission. “In addition, we plan to cease using WiMAX technology by the end of 2015.”

On top of that, Sprint plans to decommission about 6,000 “redundant” cell tower sites, out of the 17,000 total, “and terminate the underlying leases.”

Those “lease exit” costs will run between $50 million and $100 million, Sprint said.

“The timing of lease exit charges will be dependent upon the date we cease utilizing these sites without future economic benefit,” the company wrote.

Sprint was the only major operator in the United States to choose the WiMAX standard eight years ago when the 4G wars started. Verizon and AT&T both opted for LTE, and remain in a neck-and-neck race for speed and coverage superiority. WiMAX, meanwhile, appears to have suffered a fate not unlike that of the Betamax video cassette format, which lost out to the more popular VHS, in the 1980s.