WiFi signal to weak

Here's my problem. Im having problems getting a good WiFi signal. The modem with the accespoint on it are in the livingroom. Im at the second floor, on the attic. Between the accespoint and where im at, is one extra floor, the first floor. The signal that is coming from the accespoint is next to the accespoint (measured with the android speedtest.net app) 22 mbps, at the first floor around 10 mbps and at the attic less then 2 mbps. But i want to game at the attic. And i have no way of pulling some extra cables. Solid concreet floors.

Solution? Anybody?

I had the same problem, there was a floor between the modem and my content room, I did research on how to strengthen the wifi signal and learned that adapters that strengthen the wifi signal were sold, I bought one immediately and now my wifi signal is quite good, I am someone who likes to play games. I play games like, I can play the games continuously with the strong wifi speed, this was very important for me.