With the introduction of CA (comfort access)...BMW started using more aerials around the car (interior & exterior) that communicates with the remote fob. You can see the 9 CA aerials used in the F01/F02 below.
B207: Ring Aerial
E23: Exterior Aerial Driver Side
E83: Exterior Aerial Front Pass Side
E28 & E36: Luggage Compartment Aerials 1 & 2
E84: Interior Aerial Center Console Front
E22: Interior Aerial Center Console Rear
E74: Interior Aerial rear parcel shelf
E27: Rear Bumper Aerial
