My Iphone can't find nearby networks?

I have an Iphone 3G and I'm having trouble with the Wi-Fi settings. When I go to Wi-Fi settings to find nearby Wi-Fi, nothing appears. When I go to my brother's Iphone which is the same as mine, a ton of networks appear. Anyone out there know how to fix this problem?

Try turning the phone off and restarting or turn off 3G then try to manually look for Wi-Fi. If you know your Wi-Fi account info at home you can manually put it in.