Yesterday, Apple introduced a small set of changes with big effects to the AirPort Extreme Base Station and Time Capsule:

• Apple added more antennas to the existing multiple-in, multiple-out (MIMO) array in both of these devices, moving from a 2x2 array, with two receive and two transmit antennas, to a 3x3 array, with three each for sending and receiving. The new 3x3 array dramatically boosts network throughput as you get farther from a base station. Instead of seeing data rates drop off—I describe in the book how to monitor those rates—the new base station models will maintain the same speed for greater distances. Apple says the boost is as much as 50 percent over previous models, which conforms to what Wi-Fi chipmakers have said. The additional antennas also increase range, which Apple says could be as much as 25 percent farther from these new base stations than from preceding models. This is, alas, a change to the physical chip and antenna elements in the devices, so Apple can't put the improvements into a new firmware version.
• Apple also said that Time Machine backups from Snow Leopard to the new Time Capsule model have been sped up by as much as 60 percent; there's a lot of inefficiency in Time Machine networked backups, so there's a lot of room to improve. If this speed boost isn't hardware based, it could be found in a future firmware release, but it may involve better network processors or a new central processor, and thus be unavailable to older Time Capsules.

—Posted by Glenn Fleishman on October 21, 2009