The one I worked with had designed it so that they had essentially carried each of the 2.4GHz channels on a different piece of wire. I was asked to configure each AP to only use a specific channel at a specific power setting. The analogy they gave me as to how it worked was that using just an AP was similar to a single sprinkler for your lawn vs having smaller underground points all over your lawn to spread the water more evenly. They could contain the contention domain because there was a much smaller amount of power being output at any specific point. We managed to finally got it working for them, but it wasn't until nearly a year after when we did a followup survey to prove to the DAS company there were some problems with their coverage model.