I'd agree with what Chris says. I wrote this recently at MRE Mag:
QUOTE ... I think Wireless DCC (or wireless controllers) is great as it removes the clutter of controller wires and lets you move around the layout with your locos. I've used the Infra-red IRIS 66500 from Uhlenbrock and that's good, but wireless radio would be better as you don't have to worry about interruption of line of sight Infra-red.
CVP Products (www.cvpusa.com) have a good looking wireless system - The AirWire900. Their frequencies are not suitable for Europe, though. We'll have to wait for some other source.
On a BUS level, wireless is interesting. It could be an option for bi-directional hi-bandwidth data transfer. These days a wireless WiFi transceiver for home networking can fit on a USB dongle - and that's big because of the connector. CVP also produces a wireless decoder, the AW9D10 wireless receiver with built in 10 Amp motor drive, measuring 1.43 x 4.23 inches. These systems are used on garden layouts where there is no power in the tracks. Locos are either steam driven or run on batteries. More info on their site.