Realtek RTL8723BE Wi-Fi incredibly weak

Run in a terminal

sudo tee /etc/modprobe.d/rtl8723be.conf <<< "options rtl8723be ant_sel=1"

and reboot.

The ant_sel parameter enables one of the two antenna connectors of your RTL8723be adapter. Your laptop has only one antenna because the vendor is too greedy to install two. The Linux drivers can't detect which antenna connector is in use. So we have to guess it.

In Windows either the vendor sets it up somewhere on a pre-installed system, or the Windows proprietary drivers can detect it.

If ant_sel=1 does not help, use ant_sel=2. This setting tells which antenna is in use 1 or 2.

Note: I haven't tested it on Ubuntu 16.04, but it works fine on Ubuntu 18.04.

It's a problem with the drivers of Realtek RTL8723BE controller. Do this:

1. Get the new wifi drivers from github:

    git clone https://github.com/lwfinger/rtlwifi_new.git -b rtw88
   

2. Go into the directory:

    cd rtlwifi_new
   

3. Build it:

    make
   

4. Install:

    sudo make install
   

   Now the new drivers are installed. To see what is the correct antenna configuration for your laptop, do this:

5. Unload the existing module:

    sudo modprobe -r rtl8723be
   

6. Load the new module with antenna configuration:

    sudo modprobe rtl8723be ant_sel=1
   

7. Check the wifi signals using:

    iwlist scan | egrep -i 'ssid|quality'
   

   Next repeat steps 5-7 with ant_sel=2 in step 6.

8. Whichever configuration gives the better signal quality, make it the default by using:

    echo "options rtl8723be ant_sel=N" | sudo tee /etc/modprobe.d/rtl8723be.conf
   

   ---> Replace N with 1 or 2.

Note: After each kernel update, you need to rebuild the modules.

What fixed my laptop HP Pavilion with Ubuntu 16.04 is https://github.com/navilg/rtl8723be.

I had this issue with 14.04. I had a script that fixed it but when I upgraded OS this script didn't work any more.

I've not been able to use my laptop with Ubuntu 16.04 for about 4 months. This script fixed the issue completely.