"I'm really excited to be here," said the 22-year-old, speaking to Barnsley Player. "Everything happened really quickly yesterday.
"He (Danny Wilson) called me yesterday and wanted me to come play and help the team push out the relegation zone. Hopefully I can help the team achieve that this season.
"I wouldn't say I'm fit yet, but the only way to do so is to play games. The more I play, the better I'll get."
A full international with Ghana, Frimpong is yet to feature this season, but leaves Arsenal having made 16 appearances for the Gunners.
"It'll be difficult, but it's very important you start off well and make sure your first game is a good game," he added. "I'm quite confident I can do that.
"It's football and no matter where you go you have to respect your opposition. There are some very good players in the Championship."