Per Windows avevo trovato questo:
This could be achieved by enabling the Roaming Aggressiveness for your Wi-Fi adapter. Roaming Aggressiveness alters the signal strength threshold at which your Wi-Fi adapter starts scanning for another candidate AP. I suggest you to try the steps listed below and check if it works.
  • Right click the Windows icon on the taskbar and choose Device Manager.
  • Expand Network Adapters and right click on your Wi-Fi adapter.
  • Choose Properties and click on Advanced tab.
  • Under Property, click on Roaming Aggressiveness and on the right pane set it to the highest value.
  • Exit Device Manager and try automatic connection to see if it works.