Analysis and suppression for radiated EMI noises generated by radio frequency identification (RFID) based-systems

In order to pass GB 9254 Class A, a convenient method is proposed to analyze and suppress the radiated electromagnetic interference (EMI) generated by radio frequency identification (RFID) based-systems. Near-field wave impedance is employed to identify the mechanism of it. Then, several shunt capacitors are utilized to reduce the radiated EMI noises due to its fixed structure and intentional radiators. The test results show that the radiated EMI noises of two commercial RFID based-systems can be dropped well and GB 9245 Class A can be passed through.