Sprint lays out a vague path to LTE with $5B network modernization

Sprint (NYSE:S) today made the odd move of announcing a $5 billion network evolution plan without naming what technology it will be evolving to.

The CDMA operator named Ericsson (NASDAQ:ERIC), Alcatel-Lucent (NYSE:ALU) and Samsung as vendors for a new network modernization project that will allow Sprint to support its 2G, 3G and eventually 4G networks on multiple frequencies over the same multi-mode base stations. But while Sprint didn’t state whether it would continue to pursue its WiMAX strategy with Clearwire (NASDAQ:CLWR) or strike out on its own 4G path, its equipment choices give it only one alternative if it opts for the latter: long-term evolution (LTE).

All three vendors are supplying their next-generation base stations, all of which can support multiple wireless technology on software-defined radio and baseband platforms. But of the three, Samsung is the only one that offers a mobile WiMAX solution. Ericsson has never supported WiMAX, while Alcatel-Lucent offers WiMax primarily as a fixed access solution, not the mobile broadband service currently offered by Sprint and Clearwire. All three platforms, however, have CDMA and LTE support in common.

For instance, Ericsson’s portion of the contract, which will largely be to modernize the network in the former Nortel portion of Sprint’s CDMA footprint, won’t include Nortel’s workhorse CDMA base station. Instead, Ericsson has optimized its next-generation GSM/UMTS/LTE base station, the RBS6000, for CDMA, allowing it to support run both the CDMA camp’s 2G and 3G technologies as well as the GSM camps 4G technology on the same equipment, according to Arun Bhikshesvaran, chief technology officer of Ericsson North America, though he said he could not share any specifics on Sprint’s overall 4G plans. Ericsson is supplying a base station that can support any combination of CDMA and LTE carriers over multiple spectrum bands, he said, but which technologies Sprint deploys and at what time is completely up to Sprint.

None of the three vendors’ platforms support Nextel’s legacy iDEN technology, but Sprint announced today it would begin phasing out iDEN in 2013 as Sprint deploys its next generation of push-to-talk technology over CDMA. That leaves one less legacy technology for Sprint to support over the new multi-mode network.

Sprint indicated it planned to launch CDMA over the cleared spectrum, but that spectrum could just as easily be used for LTE. Nextel’s 800 MHz spectrum is within shouting distance of the 700 MHz spectrum Verizon Wireless (NYSE:VZ, NYSE:VOD) and AT&T (NYSE:T) are using for LTE, which would garner Sprint the same low frequency propagation advantages. But those networks will also support LTE at PCS, where Sprint has far more spectrum in big blocks. Since it will essentially be turning of legacy CDMA base stations at PCS and iDEN base stations at 800 MHz, it could turn on the new multi-mode base stations in whichever configuration it chooses.