What do I need for satellite radio?

I have a pioneer 4800mp for my head unit. It says that it is satellite radio ready. I plan on getting sirius sat radio. Do i just need the tuner - a href="http://www.amazon.com/gp/offer-listing/B000EYFFYS?ie=UTF8&condition=new&tag=dealtime-ce-mpfeed-20&creative=380345&creativeASIN=B000EYFFYS&linkCode=asm" rel="nofollow"http://www.amazon.com/gp/offer-listing/B…/a and then I control the channels through the head unit, or do I also need another receiver to hook up in the car also? Basically what else do I need to hook up the sat radio?