A fourth option might be a Powerline Extender. Didn't find them at Cecomsa's site but Amazon sells a lot of them
Amazon.com: powerline wireless: Electronics
You plug one in on the 1st floor, connect it to your switch or router, and the 2nd unit you plug in on the 2nd floor. Possible a small config needs to be done to secure and rename the network.
The units need to be on the same power net, they can't for example traverse from your house to your neighbour...
I use this alot in Europe.
Providing wireless solutions for this problem here in the DR could be a great business idea for someone.
Because of the building practises here, with all the rebar they use for construction, it's like sitting in a metal cage, which really attenuates any radio signal. You will never get the claimed distances on wireless devices here.
If someone could come up with a device or method of ensuring good wifi coverage throughout a whole building I'm sure it would be a good seller.
Sounds good.... any experience using it here? Anyone?
But, with the wonders reg. "power" here using it here I would not be surprised if my toaster all of a sudden has Internet access, lol...
Almost all antennas that come with routers are “omnidirectional”. That means they broadcast all the way around (360 degrees)..... but they do so in a flat donut shape. Very little up or down. Thus, a first floor omnidirectional antenna doesn't provide much coverage upstairs. Try tilting the antenna, or as others have suggested.... a second antenna (router/antenna) upstairs.
Others (on the internet) suggest a parabolic aluminum foil reflector, placed behind the antenna (on the side of the exterior wall) will reflect more signal were you want it.