T-Mobile's Faster 3G Requires Fresher Gear
T-Mobile started deploying its initial 21-Mbit/s HSPA+ in Philadelphia in 2009 and now covers 55 markets in the US with the high-speed packet access upgrade to its 3G GSM network. The operator said Tuesday afternoon that it will start to deploy the next step -- a 42-Mbit/s upgrade -- in 2011. (See T-Mobile Leaves AT&T in Its HSPA+ Dust and T-Mobile USA Promises 42-Mbit/s 3G in 2011 .) T-Mobile isn't yet saying how it will achieve the speed boost. Heavy Reading analyst Gabriel Brown, however, says that the operator must be planning to deploy the "dual-carrier" HSPA+ upgrade, which allows networks to send and receive wireless data using two channels simultaneously. This is because the 21- to 42-Mbit/s speed bump matches the profile of doubling up radio channels to increase peak download speeds, rather than the 28- to 56-Mbit/s jump seen in the multiple-input/multiple-output (MIMO) antenna-based upgrade path for HSPA+. (See MWC 2010: Dual-Carrier Duel.)
The dual-carrier technique involves bonding two adjacent 5MHz channels to double the capacity of a data connection to an end user. So the technique doesn't add additional capacity to the cell; it multiplexes the existing capacity to cope with bursty data traffic. It's a way of using existing capacity to meet ever-growing subscriber bandwidth needs.
"Its quite suited to bursty traffic like Internet downloads," explains Brown.
So, the upgrade doesn't require the expensive doubling-up of antennas at cell towers, like the MIMO-based HSPA+ upgrade or the wholesale network upgrade required for Long Term Evolution (LTE). It will, however, require new "dual-channel" devices to fully take advantage of the 3G speed boost.
Early 42-Mbit/s-compliant devices offered on the updated T-Mobile network are likely to be data-centric dongles and cards. Expect gizmos much like the Sierra Wireless Inc. (Nasdaq: SWIR; Toronto: SW) AirCard 312U wireless USB modem, launched Monday on the Telstra Corp. Ltd. (ASX: TLS; NZK: TLS) HSPA+ network in Australia. The modem maker says that users can expect "real-world" downloads of 20 Mbit/s down under.
— Dan Jones, Site Editor, Light Reading Mobile