Originally Posted by
Spiff
The power radiated by WiFi in the far field (about 1m from the transmitter) in the frequency range of avionics and communications for all practical purposes is zero watts. There is nothing to be concerned about.
I'd keep quiet and be happy the kids were entertained.
Power radiated from a single unit, say a cell phone, a DS, or a PSP is small, but not insignificant. I have seen cordless phones knock out Wi-Fi signal numerous times, as they both work around 2.5 GHz
If you have a couple of hundred of those, the total radiated power is, indeed, significant in the sense, it can be easily detected by those trying to detect it. The signals would not fry the aircraft electronics, which I am sure are shielded much better against EMI than your domestic WI-Fi routers, but can certainly produce some EMI. The FAA rule probably has less to do with the safety but more to do with keeping detectability low.
Under certain condition, depending upon your requirements, ERP from a few cell phones, is not taken lightly.