He trained with his new team-mates for the first time on Thursday and will go straight into the squad for Saturday's match at Millwall.
Karacan said: "It was good to get a first training session under my belt. The lads have all been welcoming and I've really enjoyed getting started down here.
"I see myself as a box-to-box midfielder and I like to get around the pitch. I'm not afraid to put tackles in to try and break up the play and hopefully I can also register a few goals."
Bournemouth boss Kevin Bond added: "I've seen him play three or four times. He's a little workaholic in the middle of the park. He enjoys grafting and closing people down and he's a useful type of player."