USB Wireless Realtek RTL8188SU

Com o comando lsusb veja se o dispositivo é o listado abaixo:
Bus 001 Device 002: ID 0bda:8171 Realtek Semiconductor Corp. RTL8188SU 802.11n WLAN Adapter

Depois baixe os arquivos necessários em:

E siga as instruções do artigo:

Antes instale os pacotes abaixo:
sudo apt-get install linux-headers-$(uname -r) build-essential

1) extract the driver from the driver's folder. you can use 'archive manager' or from a command line:

$ tar zxvf rtl8712_8188_8191_8192SU_usb_linux_v2. 25.tar.gz

2) make 8712 USB driver module (doesn't matter that the chipset is 8188SU), use a terminal window and navigate to the folder you just extracted

$ make

3) clean the operation environment, I needed to have root permission to get this to work

$ sudo ./clean

4) insert 8712 USB modules, with root access

$ sudo insmod 8712u.ko

After that, the blue light came on and the card was able to connect to networks via the NetworkManager applet. Hope this works for you.