IMPEDANCE MATCHING CIRCUIT, ON-VEHICLE ANTENNA SYSTEM, AND INTEGRATED ANTENNA SYSTEM

PROBLEM TO BE SOLVED: To provide an inexpensive and general-purpose impedance matching circuit capable of matching an impedance corresponding to the antennas of various forms in a simple circuit, to provide an on-vehicle antenna system, and to provide an integrated antenna system. SOLUTION: The impedance matching circuit 1 arranged between an antenna 2 and a reception part 3 includes: an inductive element 11 connected in parallel between the antenna 2 and the reception part 3; a first capacitance variable element 12 connected in parallel between the antenna 2 and the reception part 3; and a second capacitance variable element 13 connected serially between the antenna 2 and the reception part 3 and disposed in the prestage or poststage of the first capacitance variable element 12. COPYRIGHT: (C)2009,JPO&INPIT