This seems a rather frequent problem even in Loki and ubuntu 16.04: 16.04 LTS wifi connection issues and it happened very often on my system.

After following this answer it got less frequent I guess.

What it says is:

1. Get details of your PCI wireless card by running sudo lshw -class network
2. Get your card model info according to the product line. For instance, as you can see in the question description it says product: RTL8723BE PCIe Wireless Network Adapter so the model of my card is RTL8723BE
3. Open or create /etc/pm/config.d/config and add SUSPEND_MODULES="rtl8723be"(replace rtl8723be with your own model number) Then run echo "options rtl8723be fwlps=N" | sudo tee /etc/modprobe.d/rtl8723be.conf and reboot.

It rarely happens now and when it does I use the command service network-manager restart.

That can be associated with a shortcut key. I prefer a desktop launcher to run from Slingshot:

gedit ~/.local/share/applications/restart_wifi.desktop

with:

[Desktop Entry]
Icon=urserver
Name=Restart Wifi
Type=Application
Exec=bash -c 'service network-manager restart'
Categories=Network;

This seems a rather frequent problem even in Loki and ubuntu 16.04: 16.04 LTS wifi connection issues and it happened very often on my system.

After following this answer it got less frequent I guess.

What it says is:

1. Get details of your PCI wireless card by running sudo lshw -class network
2. Get your card model info according to the product line. For instance, as you can see in the question description it says product: RTL8723BE PCIe Wireless Network Adapter so the model of my card is RTL8723BE
3. Open or create /etc/pm/config.d/config and add SUSPEND_MODULES="rtl8723be"(replace rtl8723be with your own model number) Then run echo "options rtl8723be fwlps=N" | sudo tee /etc/modprobe.d/rtl8723be.conf and reboot.

It rarely happens now and when it does I use the command service network-manager restart.

That can be associated with a shortcut key. I prefer a desktop launcher to run from Slingshot:

gedit ~/.local/share/applications/restart_wifi.desktop

with:

[Desktop Entry]
Icon=urserver
Name=Restart Wifi
Type=Application
Exec=bash -c 'service network-manager restart'
Categories=Network;