This is where aluminum foil comes into play. Because metal reflects radio waves, a curved sheet of foil placed behind the router can act as a basic reflector. Instead of allowing signals to spread evenly in all directions, the reflector may help redirect more of the signal toward the areas where internet coverage is needed most.
Researchers have explored similar concepts using specially designed reflectors and signal-directing surfaces. While a homemade foil reflector is not nearly as sophisticated as professional equipment, it can sometimes provide a modest improvement in specific situations.
The key is placement. If a router sits near an outside wall, a large portion of its signal may be directed away from the living space. Positioning a reflective surface behind the device may help push some of that signal back into the home instead.