To get that kind of result, there's two potentials from a radio perspective.
The normal approach, is to use multiple APs and triangulate. This is where multiple AP radios (with varying reception levels regarding the client), and the central equipment (e.g. the Aruba controller or Airwave server) populated with AP position information give you an approximate client position.
Alternatively, you can use APs with special antennas of varying gain to build location information. This is a lot of work. It's where you install an AP with multiple radios and differing gain (and receiver sensitivity) antennas covering in one or many directions. The raw information regarding client strength then varies, and using some complicated mathematics you could determine distance.
If I were you, try option 1. It's much less work!