Looking at my router with two antennas, I have to ask; are they in phase or is there a particular shift for some directionality?
I don’t know that there’s a clean answer to this unless you give info on what router you’re looking at. A router with two antennae could possibly be doing some phasing stuff, but it’s probably likelier that one antenna is for 2.4GHz band and the other is for 5GHz.
@Stan_McIntosh
If it’s 802.11n or newer( e.g. ac) standard of WiFi – it’s definetly part of the WiFi MIMO implementation. You need at least 2 of them, but majority of the expensive models have 3 or even 4.
@Frosty and @KOSTYANTYN_RUKHLIS , thank you very much for both answers. I think I’m going to leave well enough alone. I was going to pass one through a waveguide antenna. Maybe not worth it.