A highly directional antenna is what is needed.
http://www.winegarddirect.com,HD7210P antenna. Mounting on the roof , patio or balcony is recommend. Try for a best aim at the tv transmitters. However with your reception situation a good steady reflected signal is your friend. Aim the antenna at other buildings and structures around you. Point the antenna up and point the antenna down and can even tilt the antenna left and right. Here are pictures of the front of the antenna the front of the antenna is what is aimed.
http://www.kyes.com/antenna/pointing/pointing.html. Here are places to buy antennas and etc. ,
http://www.solidsignal.com ,
http://www.amazon.com.