The problem with T-Mobile 4G? It's not 4G

Ooh, isn't T-Mobile clever? The company's new MyTouch 4G "piggyback" commercial mocks and borrows the stark white gestalt of Apple's now defunct Justin Long/John Hodgeman "I'm a Mac" commercials. It uses a pretty young thing representing the MyTouch 4G to sympathize with a guy carrying a bigger guy on his back — that's the iPhone saddled with AT&T's over-burdened 3G network. Poor iPhone. T-Mobile's answer, of course, is her, the MyTouch 4G, and its 4G network, which the company hawks as "America's largest 4G network."

There's just one problem. T-Mobile's network isn't 4G.

STRICTLY SPEAKING

Strictly speaking, neither Sprint's WiMAX nor Verizon's coming LTE network are 4G either, at least according to the ITU, the International Telecommunications Union. A month ago, the standards body finished its assessment of six global 4G technologies and determined only two qualified as true 4G: LTE-Advanced and WirelessMAN-Advanced, aka WiMAX, aka IEEE 802.16m.

So while neither the initial versions of WiMAX nor LTE qualify, there are upgrade roadmaps in place for both to meet the ITU definition of 4G within a year or so.

T-Mobile's technology? Not so much.

While ITU doesn't say why T-Mobile's "4G" network doesn't qualify, one reason may be it doesn't use a new technology such as WiMAX or LTE. Rather, T-Mobile's network is the same 3G network technology AT&T uses — HSPA, which T-Mobile has souped-up to HSPA+ (Plus).

While AT&T's plain old HSPA delivers 7.2 Mbps to the iPhone, HSPA+ has theoretical peak download speeds of 21 Mbps (which is why the company often refers to its "4G" network as HSPA+ 21), although your actual mileage may vary (upload speeds — files you send — always transmit slower, usually around half that of downloads). For instance, T-Mobile says its webConnect Rocket USB modem delivers average speeds of 5 Mbps, with peaks reported as high as 10-12 Mbps.

By comparison, WiMAX and LTE will have initial speeds of around 3-6 Mbps. Qualifying 4G technologies defined by the ITU, LTE Advanced and WiMAX 802.16m, both will transmit data between 6-12 Mbps. To keep pace, earlier this month T-Mobile announced plans to upgrade HSPA+ 21 to HSPA+ 42 sometime next year, which assumably will mean average speeds of 10 Mbps.

THE ROOM FOR SPEED

But running a souped-up BMW up to 200 MPH/321 KPH on the Autobahn doesn't make it or you Kyle Busch. Earlier this year, for instance, there were reports of Verizon LTE tests topping out at 40-50 Mbps.

Aside from the open field in front of WiMAX and LTE to grow faster and faster iterations, there's also the matter of their open field of spectrum. AT&T's (and T-Mobile's) primary connectivity issues are caused not with the speed of the network but the clutter — there are a lot of people using all 3G phones and devices in thickly populated metro areas such as New York and San Francisco in the carriers' respective slices of the 800 MHz and 1.9 GHz bands. To paraphrase Yogi: It's so crowded no one can go there anymore. And don't think Verizon won't suffer the same not-enough-room-to-swing-a-cat spectrum traffic jam once everyone rushes to get its iPhones early next year.

Unlike HSPA+, both WiMAX and LTE operate in sparkling clean spectrum uncluttered by any other radio traffic. Verizon's LTE users will rattle around unfettered — at least for a few years — in 22 MHz of spectrum in the 700 MHz band once occupied by local analog TV service. Sprint has a veritable castle of spectrum for WiMAX, a massive 120-150 MHz in the 2.5-2.7 GHz bands.

T-MOBILE & SPRINT SITTING IN A TREE...

T-Mobile will one day qualify for ITU's 4G definition — it already has indicated it will migrate to LTE, either using its existing spectrum or merging with Sprint, as recent rumors have suggested. Sprint also has indicated it will adopt LTE as a lure, but in addition to WiMAX rather than as a replacement since it has plenty of spectrum to accommodate both.

T-Mobile may be muffing this marriage proposal, however, with its insistence of calling its current network "4G." Sprint Nextel 4G President Matt Carter was recently quipped in an industry blog: "Halloween is over — it's time for T-Mobile to stop dressing up like their favorite super hero — Sprint 4G."

In the meantime, it's true — T-Mobile's HSPA+ network is faster than AT&T's and technically faster than both WiMAX and LTE. Plus, T-Mobile's HSPA+ 21 is available in 75 markets nationwide, about a dozen more than Sprint WiMAX.

It just ain't 4G.

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