Inspiron 15 3520 wifi problems after 8.1 Update!!!

I have an Inspiron 15 3520, and ever since I updated to 8.1 I have wifi problems on this laptop. It goes down every 5 seconds literally. My husband is in IT and has messed around a lot trying to fix it and even he can't fix whatever this issue is. We bought this laptop in December 2012 and it had wifi problems before and Dell remoted in and changed a few settings and it worked alright but it still had terrible wifi connection. We have other laptops in this house that have no issues with the wifi what so ever. Since Thursday when I updated it, the internet goes down, I disconnect from wifi then reconnect and then it goes down within a few minutes.