Does the radius of the WiFi signal increase with the increase in the number of router antennas?

Question

WiFi

It is necessary to distribute WiFi throughout a large apartment, breaking through a maximum of 3 walls (at the farthest point). Now such a single-antenna is used:

In general, everything works, although you can find rare places where the signal disappears completely. That is, if you move around the apartment, then the signal occasionally falls off in some places.
Question:
If you put a router with two antennas, will there be a signal in those places where it is not now?
To roughly paraphrase: will the signal become stronger, or does the second antenna add only speed / stability, and does not affect penetration?

Answer 1

Let us consider the abstract situation of an old barker with a megaphone. If you give her a second megaphone, she will yell louder. But will she be able to hear people passing by better from this?
With antennas, things are a bit better in the abstract, but not in household soap dishes - there, most often, antennas are an element of decor.

Answer 2

There is a chance that by placing different antennas at different angles, you can get a better signal at some points due to reflection.

Answer 3

www.tp-linkru.com/products/list-18.html
Pay attention to this line of equipment.
Some of the solutions allow you to have several receivers anywhere in the apartment with one connection to the router via cable.

Answer 4

WiFi repeaters are evil, huge wastage of bandwidth. Seriously, the best solution in the SOHO segment is a MESH network on MikroTik routers connected by cables and providing reliable WiFi coverage and seamless roaming. In the budget version, the price of the issue does not exceed the price of networks assembled on tlinks, long links and other shitty links, and with the right equipment settings, the result exceeds all expectations.