More info would be good, for instance:
does your network icon turn to a red x, or is it still connected but just not surfing. What does IPconfig say is your Ipaddress, default gateway when it drops.
Some things to try: When you lose connectivity, try disabling the adapter in device manager, and re-enabling it see if connectivity returns. Try safe mode with networking, if wireless stays, it's a windows issue and can be fixed through 'clean boot troubleshooting'. And, if you have any 3rd party firewalls, uninstall them or at least disable them, see if issue goes away.