How do I fix the low speed of Qualcomm Atheros AR9285 Wireless Network Adapter's ap0 in Debian?

Unlike Windows, I discovered that the speed of my Access Point is too slow about 50-70KB on Debian unlike Windows it is about 1.3MB which is the original full download speed of my connection. Here are the interfaces I have: > PHY Interface Driver Chipset > > phy0 ap0 ath9k Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) (rev 01) > phy0 wlan0 ath9k Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) (rev 01) > phy1 wlan1 rt2800usb Ralink Technology, Corp. RT2870/RT30 Unlike Windows, since I cannot use Ralink Technology, Corp. RT2870/RT3070 as AP and STA in the same time, I used Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) (rev 01) yet It is slow. How do I tweak the speed?