Issue with WIFI Del inspiron 5521

Hi..

Recently took a Dell Inspiron 5521 laptop(I5,1.8GHz). I am having issues connecting to my wireless home network. The problem is too WEIRD.. :(

Some times I am unable to connect to any network ..For a while it could connect to the network but disconnects..and sometimes it lists out all the network EXCEPT my home...

I have installed all the latest drivers from dell site providing my service TAG. (Inspiron 5521,NonTouch display)..

Issue is also seen on Windows 8;I am using Windows8.1 ;64bit....64 bit.Router is Windows-8 supported.(TP-Link)

I could connect to the same network using my friends laptops and even with my mobile.

 I am able to connect to network (70% sucess)within 2 to 3ft. I dnt think this is a problem as all the other devices(rel;atively older than mine) could able to connect with the same network.

Thanks in advance...