I 've installed its driver following these steps:
sudo apt-get install build-essential linux-headers-generic git
git clone https://github.com/lwfinger/rtl8192du.git cd rtl8192du
make
sudo make install
sudo modprobe 8192du
After installation, it only detects 2.4GHz connection. Did I get the driver wrong? my model is F9L1101au.