HIGH-FREQUENCY INTERFERENCE RESISTANT RF ANTENNA IMPEDANCE-MATCHING CIRCUIT AND DESIGN METHOD THEREOF

摘要

Provided are a high-frequency interference resistant RF antenna impedance-matching circuit and design method thereof. The circuit comprises a first port A and a second port B respectively connected to an RFID module and an RF antenna. The first port A comprises a connection wire A+ and a connection wire A-. The second port B comprises a connection wire B+ and a connection wire B-. An inductor L is connected between the connection wire A+ and the connection wire B+. A capacitor C1 is connected between the connection wire B+ and a ground wire GND. Further, a capacitor C2 and an inductor L2 are connected in series between the connection wire B+ and the ground wire GND. An electric path between the connection wire A- and the connection wire B- and an electric path between the connection wire A+ and the connection wire B+ are symmetrical with respect to the ground wire GND. Dividing a matching capacitor of a traditional impedance-matching circuit into two capacitors C1 and C2 arranged in parallel and selecting proper capacitance values for the capacitors ensure matching performance of the circuit while suppressing a high-frequency spur at a specific frequency outside an operating frequency band, thereby improving wireless communication performance.