In July 2010, Apple acknowledged that iPad users were experiencing Wi-Fi connection problems. After identifying the symptoms, the company published a support document with solutions on their website. Some iPad users have discovered and suggested their own solutions, which you can try to fix your device's Wi-Fi connectivity problem.
Open the "Settings" app from the iPad home screen. Go to the "Wi-Fi" setting. Select the network you are connected to and tap the "Renew Lease" option. When prompted, touch the "Renew" button.
Select the network. Tap the "Forget this network" option. When prompted, touch the "Forget" button. Afterward, you will need to select the network again. Type in the password.
Adjust the iPad's screen brightness. Go to the "Brightness & Wallpaper" under the "Settings" menu. Move the slider left or right to adjust the brightness. Apple reports this as a possible solution, but its unknown how this actually fixes the connection.
Go to the "General" option from the "Settings" app. Scroll down to the bottom of the next page, click "Reset" then "Reset Network Settings." Tap the "Reset" button when prompted.
Remove any covers or cases from the iPad. Sometimes these accessories interfere with the Wi-Fi antenna's reception.