MATCHING CIRCUIT

PROBLEM TO BE SOLVED: To provide a matching circuit that allows reducing the loss of an input signal with respect to an amplifier circuit and increasing the output of the amplifier circuit.SOLUTION: A matching circuit 10 connected to an input of an amplifier circuit for amplifying a reception signal from an antenna is composed of a variable control LC circuit 20 and a control section 30. The variable control LC circuit 20 is composed of a variable capacitance 22 and a coil 21 that are connected in series. The variable control LC circuit 20 has its one end connected to an input of a collector-grounded transistor amplifier circuit 40 so as to branch and has its other end connected to the ground. The control section 30 controls the variable capacitance 22 of the variable control LC circuit so that the impedance viewed from the antenna side is matched.