My call of duty world at war wont work online?

i go online on my ps3 to play call of duty,but it wont work. i click join match and it keeps on saying finding host. gettinf match quility, and stuff. i wont join me in with people. it puts me by myself, and it sais waiting for 3 people to join. HOW DO I FIX IT!!My call of duty world at war wont work online?
I don't have a PS3 but try signing out of your profile and signing back in.My call of duty world at war wont work online?
I have this same problem with my ps3 but on the game call of duty modern warfare. If you are using a wireless connection try moving the console closer to the modem it works, that most likely means you have little or no signal.