You could have seperate brands within the same single ownership.
You could have multiple companies with a holding company tying them together.

One thing I'll warn about now - managing multiple entities is quite a challenge. There are issues that crop up that you don't get in the single cell business entity.

If you are doing this only for marketing reasons, I'd go the multiple-brand-in-one-company route. If it is for other reasons... Perhaps best to explore that only if it is a bridge you are going to cross.