Creative midfielder added to squad.
The twenty-seven year old has put pen to paper on a contract through to January, after being released by Crystal Palace in the summer.
He made over eighty appearances for the Premier League side, and has spent his entire career in the top two flights of English football.
U's boss Tony Humes was delighted to have secured Garvan's services, saying: "Owen will certainly add to the quality we already have in the squad.
"He has played at the top level and is at an age when players traditionally start reaching their peak.
"It's fantastic that we have been able to get him here and we're confident that he will fit in extremely well."
Garvan is expected to go straight into the U's squad for the weekend's game against Scunthorpe United, subject to the contract gaining approval from the relevant bodies.