Antenna apparatus and related communication systems for use with vehicle lamps are disclosed. A disclosed communication system for a vehicle and a trailer includes a lamp positioned on the vehicle and a conductive structure coupled to a stylized component of the lamp. The communication system also includes a primary antenna at least partially formed by the conductive structure and electrically coupled to a vehicle electronic device. The communication system also includes a secondary antenna positioned on the trailer and electrically coupled to a trailer electronic device. The primary and secondary antennas, together, are configured to interact with each other to provide wireless communication between the vehicle and trailer electronic devices.