PLEASE HELP! ADSL Modem/Router Question

Ok I want to connect my PS3 wirelessly. Right now I have a Westell 6100 ADSL Modem. I was thinking about getting a D-link DIR 655 Xtreme N Wireless Gigabit Router.
So my question is, since I have an ADSL Modem do I have to have an ADSL Wireless Router or can I use the D-Link.