I upgraded to a (hand me down) Dell Latitude E6530 not long ago.  I loaded it with Windows 8.1 (and Classic Shell, because one must).  I kept having wireless trouble – dropping off of networks.  It wasn’t isolated to my home.  What I believe I’ve determined is that, in a nutshell, Windows handling of N networks kind of sucks.  I disabled N and since then have been rock solid.

Navigate to your network adapters, right click on the wireless and choose Properties.  Beneath the adapter description choose Configure:

Choose the Advanced tab, then locate 802.11n Mode.  Switch the Value to Disabled and OK  your way out of all.