Wireless Networking

I have a home LAN with a number of wireless devices connected and sharing files,
Laptop – wireless
Desktop – wireless / Ethernet
PS3 – wireless
Radio – wireless

My desktop PC is new as is the wireless NIC < Belkin>
I am running windows XP Home edition SP2
My problem is while the wireless NIC connects successfully and allows internet connections. Its coneection will, intermittently drop, drop offline. Windows shows as limited connectivity and reconnection can prove problematic. I’d like advice to know whats causing it or a utility that can help PD the problem.
All other devices remain connected from the moment they connect.