Originally Posted by Gazoobee
Good theory, except the teardown reveals that there is only one antenna in the new
design, and there are actually multiple antennas in the old
design. Also, it makes no sense because if beamforming relies on the position in the room of the (single) antenna, i.e - if moving the antenna six inches in the air makes it work better, then "beamforming" itself is basically a useless technology. For beamforming to be useful at all, it needs to be able to locate and send the beam to devices at 360 degrees around the base station and at almost any elevation above and below it.
There's a bunch of inaccuracies in your post. There are a total of six antennas, 3 per band. The antenna module contains 6 antennas but also uses the metal chassis as well as the table as a ground plane, in the same way the metal of your laptop screen forms part of the antenna. This results in a very complex interaction. The only way to design these systems are using extremely complex simulations. While the antenna is fed from the top, you don't know how it acts or where its center is at without the math.
Beamforming electornically forms a beam that automatically points in the direction of your station. MIMO forms multiple beams. This is the basis of 802.11n and LTE. It has been around for years. If it is a "useless" technology, then none of that would work. It is also why
Patch antennas are a lot cheaper than the stick (dipole) antennas. Additionally, the center (phase center, to be exact) of the stick antenna is what matters and would still have to be separated.
The fact is that 802.11ac requires better array characteristics over a much wider bandwidth and the laws of physics say you need to separate the antennas more.Edited by konqerror - 6/12/13 at 12:53pm