RADIO COMMUNICATION DEVICE

PROBLEM TO BE SOLVED: To provide a radio communication device capable of automatically conforming a resonance frequency of an antenna to a receiving frequency with a matching circuit while suppressing expansion of circuit size.SOLUTION: A radio communication system includes a control circuit 70 for implementing a tuning mode to a matching circuit 20 when an antenna 50 receives a frequency signal emitted as a radio wave from a local oscillator 36 of a receiving circuit 30 in such a state as to connect the antenna 50 and a matching circuit 20 with a switch 40, and an antenna 10 and the receiving circuit 30 with a switch 41, and a resonance circuit is composed of an antenna 10, the matching circuit 20 and the antenna 50 that are resonated by the received frequency signal. A capacitance of a variable capacitance capacitor 23 is controlled to make an RSSI voltage conform to a voltage value V0 during the tuning mode implementation.