The senior was granted a release from his Arkansas scholarship earlier this month after competing with Brandon Allen for the starting quarterback job this past spring.
Because Mitchell has already graduated from Arkansas, he'll be eligible to play immediately for the Wolfpack.
"Bottom line is I want to win, and I want to win now," Mitchell told Schad. "They have the best opportunity for success and just had one missing piece."
Mitchell appeared in 21 games at both quarterback and receiver over the past three seasons for the Razorbacks, so he brings some experience to the table. He appears to be a good fit for head coach Dave Doeren's up-tempo offense, but to win the starting job he'll need to beat out Colorado State transfer Pete Thomas (21 career starts) and sophomore Manny Stocker (two career pass attempts).