The wireless broadcaster (router) is the eqiupment that has to be set up, not your PS3. Depending on your brand, you'll have to access the router interface (check manual or manufacturer's website for model specific instructions) and from the wireless section browse for wireless mode or speed and restrict it to Only G.
Believe it or not, Wi-Fi and internet are two different Netflix's Fast.com is a good service to test your internet connection. Dong Ngo/CNET Q: My broadband internet connection is at least 50Mbps when I connect via a network cable, but via Wi-Fi it's networking - Why is my PS3's internet so slow compared to Oddly the PS3 is getting consistent 4.3 Mbps up and occasionally can hit 8Mbps down. Still a far cry from the low end 11 that my wireless PCs get. edit. HA! Just ran another speed test using the Internet Connection Test in the XMB 19.3 Mbps down 2.2 Mbps up. I didn't change a thing. Maybe the PS3 connection test software is just whack. ps3 wireless internet connection? | Yahoo Answers
How can i get ps3 game system to pick up a wireless
PS3 Internet Connectivity Problems | Tech Support Guy Aug 02, 2008 How to connect your computer to your PS3 - CNET
PS3™ | Internet Connection Settings (wireless connection)
Contact your internet service provider for more information. Ensure that all network equipment supports 802.11b or 802.11g wireless protocols. If your wireless network is protected by a WEP or WPA password, double check that this has been entered correctly. The Media Server connection may interfere with the PS3 system’s internet connection.