T-Mobile picks Ericsson to build its new tricked-out LTE network

Considering Ericsson built a good deal of T-Mobile’s first LTE network, it should come as no surprise that T-Mobile US has tapped the Swedish network infrastructure giant to complete the next phase of its ongoing 4G rollout. Ericsson announced on Tuesday that is building new LTE systems in the 700 MHz and 1900 MHz PCS bands for T-Mobile as well as providing the baseband processing glue that will meld those different networks together.

Specifically, [company]Ericsson[/company] has started building new 4G base station gear in the 700 MHz frequencies that T-Mobile bought from Verizon last year to help fill in its 4G footprint outside of metro areas. And it’s cannibalizing old 2G and 3G airwaves in the PCS band for more 4G capacity. T-Mobile’s main LTE network sits in the Advanced Wireless Service (AWS band) at 1700 MHz and 2100 MHz.

Instead of operating all three as different networks, though, Ericsson is laying the groundwork for unifying them into one big ultra-fast system. Using an LTE-Advanced technique called carrier aggregation, Ericsson will be able to bond the downlink transmissions of two or more bands into one big fat data pipe.

[company]T-Mobile[/company] hasn’t announced any specific timeline for implementing carrier aggregation, but it’s safe to say it’s on all U.S. carriers’ roadmaps. [company]AT&T[/company] has already spliced together networks in Chicago and other cities, while [company]Sprint[/company] plans on beefing up its Spark network with more airwaves by the end of the year. In any case, it will probably be a while before we’ll be able to tap into a radio-busting 500 Mbps link on a T-Mobile smartphone or tablet, but at least Ericsson is getting the network prepped.

Ericsson CEO Hans Vestberg holds up the vendor's smallest small cell, the Radio Dot (Photo by Kevin Fitchard)

Ericsson CEO Hans Vestberg holds up the vendor’s smallest small cell, the Radio Dot (Photo by Kevin Fitchard)

Ericsson also revealed it’s deploying small cells in T-Mobile’s network. These tiny little base stations pile a lot of capacity into small area, making them ideal for feeding our growing data appetites in dense crowded areas like malls and outdoor plazas. Finally, Ericsson has been helping T-Mobile out with its voice over LTE and voice over Wi-Fi deployments, providing the gateways that turn plain old 2G calls into VoIP calls when we switch between GSM and LTE or Wi-Fi connections.

T-Mobile actually has two primary LTE vendors. The other is [company]Nokia[/company] Networks, who is curiously absent from any official contract announcement today, but that doesn’t necessarily means it’s on the outs with its most important U.S. customer. When big carriers – and in the global scheme of things T-Mobile still counts as a big carrier – build things they tend to rely on multiple suppliers, awarding them different geographical areas.

It’s a handy way of playing your suppliers off of one another and gives you a fall back in case something unexpected happens (like a vendor going bankrupt or exiting a key technology market). We’ll probably see a similar announcement from Nokia shortly. If not, well, then Ericsson has scored a major coup.