Sensitivity and Impedance Measurements of UHF RFID Chips
This paper describes the sensitivity and impedance measurement method for UHF RF Identification (RFID) chips. The measurements are performed using an RFID tester (RFID reader with variable output power and frequency) and a vector network analyzer. No special impedance matching is required: chips can be connected to standard 50-Ù connectors allowing the sensitivity and threshold impedance to be measured directly in a fast and efficient way. The paper presents experimental data for two UHF Gen2 chips (NXP UCODE G2XM and Impinj Monza in thin-shrink small outline packages. The results have been verified using two chip assemblies matched to 50 Ù. This method can also be applied to chips in other packages: flip-chip, strap, etc.