Antenna orientation on a 4x4 MIMO capable access point A general rule of thumb for a 3x3 MIMO system antenna orientation is: 1. Keep the center antenna upright at 90 degrees 2. Keep the outward antennas leaned outwards at 45 degrees I was wondering what could be a general rule of thumb antenna orientation for a 4x4 MIMO system. I understand no orientation is the 'best' and it depends on the channel environment, client antenna polarization, etc. but I needed a generic answer.

Depending on your locale (upstairs, downstairs), use 90° orientation for current floor, 0° for upstairs, downstairs, and 45° for upstairs/downstairs, a bit displaced from where the AP is sitting.

Have at least two in 90° position. It affects the polarization of the radiowaves, and it's often helpful to mix this up. Laptops usually have two small patch antennas which sit at the top and side of the screen, one oriented vertically and one horizontally. If you need to cover one direction only, place a large copper plate/mesh on the opposite side of the direction you want to cover. It will reflect. You can also use wallpaper/paint infused with metal particles to get better coverage (a bouncy cage), and reduce interference from unwanted 2.4GHz sources.

For longer ranges, use bigger omnis, or patch antennas. I have found big omnis and patch antennas to be a lot more useful than e.g. parabolics, which are only useful for point-to-point links.