He joined Frosinone on a permanent deal in the summer, but revealed his disappointment at not being able to work with Emery.
Campbell told Goalof his Arsenal experience: "To be able to train and to play with those players was great. Wenger is a fairly quiet coach, but I liked him because he was one who gave a lot of freedom to his players on the pitch: he believed in the most technical players and he tried to put them in the starting XI.
"I have no regrets because I tried to use my opportunities and I don't think I did badly when I was called into action.
"This summer I believed I could be part of Emery's project, I spoke with the coach and the club, I was sure that I could do well in a technical system like that of the Spanish coach but the club had different ideas. It was a great experience that I will never forget because English football is something gigantic."