If your bed frame is a traditional bed frame that has more than 1.5 inches between the slats then it won't support the mattress.
You'll need to get a special frame for the sleep number bed if your current frame is one with wooden slats that sit far apart.
It's recommended to either use a solid surface platform bed frame or a bunkie board.
Or just get the base that goes with the sleep number bed so you know you won't have any problems.