Wireless – How to Install TP-LINK TL-WN722N Wireless Antenna

Run lsusb to make sure the machine recognizes the adapter and confirm the chipset. You should see the following on one of the lines:

0cf3:9271 Atheros Communications, Inc.

The machine needs both the proper firmware and driver to utilize the adapter. Get the htc_9271.fm firmware file from here (I used version 1.3, get whatever is most recent) and copy it to the lib/firmware/ directory. Next, download the compat-wireless drivers here. Unarchive it and build the ath9k_htc driver by running the following commands in order:

tar xvf compat-wireless-2.6.38.2-2.tar.bz2
cd compat-wireless-2.6.38.2-2
./scripts/driver-select ath9k_htc
make
sudo make install 

Load the driver

sudo modprobe ath9k_htc

If this does not work (you should now see wireless networks available), try unplugging the adapter and reinserting it. Also, a reboot might help but could require reloading the driver with modprobe again.

All right, looks like I found a solution: I tried using laptop+TP-Link TL-WN722N with another router and suddenly the wifi stick was able to deliver the expected performance.

In the end I managed to narrow it down to a setting of my router called "WMM" (also called Wifi-Multi-Media or Wireless-Multimedia-Extensions or WME).

If I disable WMM in my router, the wifi stick delivers the expected 25 Mbits/sec that my internet connection is capable of.

However, please note that if you disable WMM/WME in your router settings your router will reduce its wifi speed to 54 Mbits/sec (IEEE 802.11g).

Summary:

On Windows the TP-Link TL-WN722N works as expected.

On Linux the TP-Link TL-WN722N only works correctly with IEEE 802.11g. If your TP-Link TL-WN722N is slow, you need to disable WMM or WME in your router settings.