The Irishman joined the Cherries on a three-year deal from Torquay on Friday, where his performances last season saw him included in the PFA League Two team of the year.
"An attractive style of play is what I what to be involved in and that's what brought me to the club," O'Kane, 22, told the club's official website.
"A lot of attacking players have arrived so hopefully we'll score plenty of goals.
"The club also has a good track record of producing and developing young players which was another reason why I signed.
"I'm ready for a new challenge here and I'm hoping it's a successful journey. Every footballer wants to play at the highest level and hopefully we can challenge for the play-offs this year."