Hi Naveenkandipu,
Inspiron 7520 SE is usually shipped with the following types of wireless card:
D1703 WiFi + Bluetooth 4.0 Half Mini Card
1704 WiFi + Bluetooth 4.0 Half Mini Card
1901 WiFi + Bluetooth 4.0 Half Mini Card
Intel® 2230 WiFi + Bluetooth 4.0 Half Mini Card
Intel® 6150 WiFi / WiMAX Half Mini-Card
You may check the Wireless card shipped with your system from the following link http://dell.to/13LWJoE -> type the Service tag of the computer -> click on System Configuration -> Original Configuration.
You can download the drivers from Here.
Hope this helps.