[ubuntu] Hosting wifi disconnects 3G modem

view story

http://ubuntuforums.org – I use airtel 3G modem. To use internet on my iPad, i host an adhoc network. For a few minutes, internet works fine but then it disconnects automatically. When I don't host the wifi, internet works fine. I am able to use connectify on windows and it works fine. Any ideas, how to fix this. (Hardware)