LTE Innovation Summit: Sprint’s multi-mode network, smart antennas and Wi-Fi


SAN DIEGO — Sprint Nextel Corp. is working to deploy a network that will be multi-band and multi-mode, including both FDD and TDD flavors of LTE, according to Doug Alston, director of technology and strategy for the carrier.

Alston was speaking at the LTE Innovation Summit in San Diego, Calif., this week, which covered topics from base station antennas to the role of Wi-Fi and LTE-Advanced network features.

Alston said that after years of the telecom industry talking about a “killer app” for mobile, “The killer app is video. And that killer app is eating us alive. It’s putting a great strain on our networks.”

In addition to huge increases in data traffic, Alston said, telecom operators are also in the midst of the transition from voice-centric, best-effort data networks to being broadband networks that implement quality of service functions. The huge shift from most wireless traffic being generated outdoors, to 60-70% of traffic being indoors, has also impacted operators’ view and strategy.

“Mobility is still important, but indoor and outdoor traffic is important, and high capacity is important,” he added.

In terms of LTE-Advanced features, Alston said that Sprint’s priority is for Band 41 carrier aggregation and not so much its Band 25-26 holdings, and noted that contiguous CA is easier than non-contiguous. The company, he said, “is focused right now on the pieces that are easier, the low-hanging fruit. In the longer term, I think carrier aggregation between TDD and FDD can be contemplated, but it’s not something we’re focused on at this time.”

Arnaud Meylan, a senior engineer in corporate R&D systems engineering at Qualcomm, told the audience that smart Wi-Fi offload is increasingly part of the wireless landscape.

“People would refuse to buy  a phone that does not have Wi-Fi,” he said.

He held up a small piece of paper on which the user name and password for Wi-Fi access for conference attendees was written to illustrate the biggest hurdle for more Wi-Fi offload: authentication.

“Carriers cannot post pieces of paper everywhere they want you to use the Wi-Fi,” he noted. However, authentication from information on SIM cards can be used for authentication, he noted, making it possible for the operations to be seamless.

Keith Radousky, CTO of antenna provider Quintel, told the audience that although small cells are getting a lot of attention, advanced antennas offer promise for increasing coverage and capacity in non-urban areas where operators can’t afford the backhaul or operating costs of other infrastructure approaches. Quintel has done two trials of its technology and will soon start a third in May.

“There hasn’t been a lot of innovation in base stations, compared to other parts of the ecosystem,” Radousky said. “This has been a very slow area to progress, and this is the challenge of the future. The tower top is the only way to harness the power of the advanced air interfaces coming at it.”

And those technological advances are coming. Axel Meier, project manager for LTE RF conformance test systems at Rohde & Schwarz — which sponsored the conference — noted that there are now 415 network operators who are investing in LTE, with 163 launched networks around the world, and almost 400 LTE devices introduced last year.

“LTE is driving all of us,” he said, and the three main features of LTE-Advanced are carrier aggregation, extended downlink MIMO and uplink MIMO, and intercell interference reduction.

Standards body 3GPP started with one interband and two intraband carrier aggregation specifications, and is working on dozens more interband combinations to cover network operators globally, Meier said.

“LTE is exploding much faster, compared to the technologies before,” Meier said. “The whole industry is pushing that.”

About Author

Kelly Hill

Editor, Big Data, Analytics, Test & Measurement
Kelly Hill currently reports on network test and measurement, as well as the use of big data and analytics. She first covered the wireless industry for RCR Wireless News in 2005, focusing on carriers and mobile virtual network operators, then took a few years’ hiatus and returned to RCR Wireless News to write about heterogeneous networks and network infrastructure. Kelly is an Ohio native with a masters degree in journalism from the University of California, Berkeley, where she focused on science writing and multimedia. She has written for the San Francisco Chronicle, The Oregonian and The Canton Repository. Follow her on Twitter: @khillrcr