Sprint hints at 6 Gbps sector capacity over LTE network

DALLAS—A top Sprint executive said that the operator could use a combination of several key wireless technologies, including massive MIMO, to eventually offer sector capacity on its LTE network of up to 6 Gbps.

“We are investing a lot of work into massive MIMO,” said Günther Ottendorfer, Sprint’s chief operating officer for technology, here at the FierceWireless Next-Gen Wireless Networks Summit.

Today, Ottendorfer said Sprint makes use of roughly 60 MHz of spectrum with 2x2 MIMO and 64 QAM across three sectors. He noted that Sprint has already tweaked several of those figures in order to reach LTE speeds approaching 1 Gbps. And in Sprint’s LTE network evolution Ottendorfer said the carrier can potentially—partly through the application of its massive trove of 2.5 GHz spectrum holdings—increase those figures to 120 MHz, 64x64 MIMO (16 layers per sector carrier) and 256 QAM to reach sector capacity of up to 6 Gbps.

Of course, all such wireless speeds may be reached in a lab or test setting, but may not actually reach end users in a live network due to factors ranging from overall network usage to the customers’ geographic distance from a tower or other transmitter.

For massive MIMO specifically, Ottendorfer said Sprint’s antennas could use 64 transceiver units, each mapped to two antenna elements.

But massive MIMO is just one technology that Sprint plans to use in its LTE network. Ottendorfer said the carrier plans to use other LTE-Advanced Pro technologies like carrier aggregation across up to 32 carriers. The carrier has already deployed carrier aggregation across several carriers and spectrum bands.

Of course, Sprint’s network activities aren’t limited to its LTE network. The carrier has already tested 5G network technology and plans to eventually deploy the technology in its various spectrum bands, including its 2.5 GHz spectrum holdings. Indeed, Ottendorfer explained that Band 41, which covers Sprint’s 2.5 GHz holdings, has been designated as an initial band for 5G NR technology. He also added that Sprint is the only U.S. carrier with over 100 MHz of licensed, contiguous spectrum below the 6 GHz threshold. “That will give us a huge advantage,” he said.

Overall, Ottendorfer said that the impact of the nation’s move to 5G network technology could create $500 billion in U.S. GDP growth and $275 billion in investments, which includes $93 billion in direct network construction. “That is significant,” Ottendorfer said.

However, to reach those projections for 5G in the U.S. market, Ottendorfer said that carriers, U.S. regulators, industry trade groups and others will need to address several key items, including paving the way for carriers and vendors to more easily deploy small cells and other network elements more quickly. “It takes a technician an hour to deploy a small cell, but it takes a year to obtain the permit” for that small cell, Ottendorfer said. “We would like to see all states pass small cell legislation,” he added, explaining that roughly a dozen state legislatures have already passed legislation along those lines.

“5G will bring a world of new opportunities,” Ottendorfer said.

Ottendorfer’s comments are noteworthy considering Sprint parent SoftBank recently pledged to increase its investment in the carrier in order to raise Sprint’s annual capex spending from a recent low of around $2 billion to as much as $6 billion. However, for Ottendorfer specifically, he recently announced he will be leaving Sprint by the end of this year, and Sprint’s network efforts will be taken over by CTO John Saw.

Article updated Nov. 30 to change "speeds" to "sector capacity."