A low profile, conformal antenna assembly provides wide bandwidth, orientation dependent and directional operation via volumetric radiating elements that are diposed over a cavity. The volumetric antenna elements may be further controlled by embedded inductive or capacitive components and/or surrounded by frequency-selective components. An optional AM/FM radiating structure is provided by a conductive wire helix disposed within the cavity. The antenna assembly may be integrated with system and control, conversion, amplification and/or processing electronics in a single enclosure or tightly coupled enclosure space. Integrating the antenna subassembly with an electronics subassembly in the same enclosure eliminates the requirement for discrete RF signal connections reduces associated costs, and avoids signal losses in the connections to multiple vehicle systems. The antenna can be mounted to the inside surface of glass in a vehicle.