[Problem] To provide an antenna system that excellently dissipates heat to the outside of a housing, said heat having been generated by means of an electronic component. [Solution] An electronic circuit board 10 has an electronic component mounted thereon, and has an antenna that is formed on one surface. A protection member 20 covers the one surface of the electric circuit board 10. A heat transfer unit 30 transfers heat to the protection member 20, said heat having been generated by means of the electronic component mounted on the electric circuit board 10.