Okay everyone in our family has Linux, my mom has Xubuntu, I have Ubuntu and my brother has Mint, so we are all based off Ubuntu. Their internet works perfectly, but mine cuts out randomly. Like at one point it'll be downloading something at 3.00 mb/s, then randomly it'll cut down to 0. I'm not sure why though.

Heres my wireless card. (My brother has the same computer, so we have the same card.)
~:$ lspci | grep -i net
02:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) (rev 01)
08:00.0 Ethernet controller: Atheros Communications AR8152 v1.1 Fast Ethernet (rev c1)
Also speedtest.net sais this: (Although I've never seen that speed for download before)

How could I fix this??