I am using windows xp machines. I have recently moved to the new apartment.

After that my wireless network getting disconnected every now and then and I always have to use the repair option to reconnect the wireless.

Can somebody tell me why is this happening and how it can be fixed?

You might try disabling the "Wireless Zero Config" service.

Here is a good description (http://tech.ifelix.net/2000.html).

Good Luck,
WallyH