The midfielder rebuffed the approaches of Celtic and Borussia Dortmund before joining Malky Mackay's side from Cerezo Osaka in July last year.
The South Korean international, 23, has suffered a frustrating spell on the sidelines with Mackay opting to reshuffle his pack in recent weeks.
However, he insists he is ready for more glory on the pitch after being voted fans' man of the match following Monday's 3-0 win over Blackburn in his first start since February 9.
"It's been a big experience for me," he told Wales Online. "I have learned such a lot since I joined this club.
"An important factor is that I am enjoying my time in Wales. I am proud to be playing for Cardiff, a club who are top of the Championship.
"I've enjoyed playing Championship football, but it would be a great experience to play in the Premier League.
"I played in the Olympics and in World Cup matches for South Korea and they are the highlights of my career so far.
"But if I can play my part for Cardiff in their promotion challenge that would be right up there."