Loss of a wifi connection is unlikely to have anything to do with a computer. It's far more likely to be a router problem. If, for example, a neighbour has recently installed a router using the same radio channels as yours does, then you may well be suffering interference problems. (Interference can also come from many other electrical devices. If you, or a neighbour, have recently bought a new TV, that could be the cause of your problems).
You should try changing the channel used by your router. The instructions for accessing your router's settings should have come with it but, if you've not got them, we can probably help if you'll tell us the make and model of your router..
Chris