I think I have found a solution to this problem. After trying all of the above obvious and not so obvious fixes (I did not crack the cover and mess with the antenna) Give this a try. Open adapter advanced settings and disable BLuetooth Collaboration. Seems to have solved my problem. 20% signal when 5 feet from the Access Point to 90%. In a room where I was not connecting at all I now have 60 to 70% signal strength.
Windows 8 64 bit. Inspirion 3520