|If your laptop is completely losing the signal, and the wireless router is within line of sight then they're may be an issue with either the router itself, or your wireless network interface card in the laptop (or antenna too.)|
Are you able to successfully hold a connection while connected to another AP? (a friend's house or at work, for example?) It would be nice to isolate the faulty device.
One other thing of note is the amount of interferrence in your environment. Basements are notorious for sucking up RF energy due to many factors. The brick walls, metal piping and subterranian nature of basements make them a natural enemy for wireless signals. Also, the interferrence from flourescent lights and microwave ovens can degrade Wi-Fi performance too. Just food for thought...
If it's worth doing, it's worth doing right.