A receiver includes a circuit board and a dielectric antenna. The circuit board has a receiving circuit on a first surface, and a ground pattern on a second surface. The circuit board is disposed close to a rear window of a vehicle so that the ground pattern faces a roof panel. The dielectric antenna extends from an edge of the circuit board toward and along the rear window. As a result, the roof panel capacitively couples with the ground pattern, so that the roof panel becomes imaginary ground. The dielectric antenna functions as a monopole antenna with the imaginary ground. It is not influenced with a metallic material of the vehicle.