T-Mobile's not quite ready to put it's full support behind the 4G mobile broadband infrastructure. Instead, they want to take the current 3G HSPA standard they're using, and make it as fast as 4G, reaching speeds of 650Mbps.
How, you ask? According to Ars Technica, Nokia has teamed up with Nokia Siemens, and together, they're developing a 3G antenna array that is similar to MIMO (multiple in, multiple out) technology used in wi-fi routers. By having a device pick up and broadcast multiple frequencies using more than one antenna, they can fuse those signals together to create a super frequency with increased speeds.
Currently called Long Term HSPA Evolution (which isn't confusing AT ALL), T-Mobile's embrace of this standard would give them an early advantage on competitors since they would have to rollout an entirely new infrastructure—all they'd need to do is swap out antennas and get manufacturers to make new handsets. And as Ars points out, they wouldnt have to abandon the 3G networks which they adopted later than the competition and have already dumped a bunch of money into. But seeing as it's just been approved for study by the 3GPP standards committee, who knows when we'll see this in action. [Nokia Siemens via Ars Technica]