I have a RevI Actiontec router with dual antennas(not sure of firmware as I am not at home). My wife can be on her laptop all day, then when I come home with my IPad, it make her lose connection to the router. The router still connects to my iPhone 4 and iPad (both with iOS 6.0.1), but she is unable to connect to router at all. Everything continues to function normally on my Apple devices, so we are still connected to the internet. I have a laptop as well, and when this is happening, both of the laptops stop connecting, but the apple devices and our Toshiba TV and BluRay players continue to function normally. As a temp fix, I disconnect internet from my iPad and restart the router. It works until we try to run both at the same time.
I am mildly computer literate, though I know little about network setups beyond security, MAC filtering, and other slightly advanced setup stuff.
This is really frustrating and seems to be getting worse. We used it like this in our new house for several months before this started happening.
might just be the channel in your router and interference that the one device is sensitive too.
open a browser 192.168.1.1
admin is username
login password printed on your service tag on the router.
go to wireless settings at the top menu
change channel. try 1,6 and 11 and see which works best.
Also check to make sure neither of the devices are set to use a static IP address.