anjalimay6,

You can click the link below and input your system service tag. The site will show you the drivers needed for your computer. From the list choose your wireless driver to download and install.

http://dell.to/1I5BT9X

Provide hardware IDs and your version of Windows:

http://dellwindowsreinstallationguide.com/downloading-drivers-checking-hardware-ids-and-downloading-and-installing-dell-system-drivers-in-the-correct-order/checking-hardware-ids-in-the-device-manager/