Since I used Ubuntu version 12.10, I connect Wi-Fi & internet running normally at a distance of approximately 5-10 meters of range of the router or parallel to the floor of the room. After I upgraded to 13.04 and I connect to Wi-Fi in same distance, my laptop cannot connect to Wi-Fi, except when my laptop with a distance of 1 meter, It can connect. I've followed the stages from Ubuntu documentation/instructions in Wireless troubleshooter section page and have done all sorts of ways to solve the problem, but the problem still relapse. I think this is bug. How to solve the problem? Anyone idea to solve it?