Yes. Many existing FM aerials are ‘helically wound’. A helically wound aerial is short and stubby, and is usually roof-mounted. It is most often fitted to newer models and is designed to amplify the FM signal, so it may not work effectively with a DAB radio.
You can either buy a combined FM/DAB roof mounted aerial for your car and replace your existing aerial with it, or you can buy a separate DAB aerial to sit alongside your existing FM aerial. There are two types of DAB aerials available for the car, either a magnetic mount for steel panels, or an active glass strip aerial, which is an adhesive amplified antenna for glass mount.