Sensitivity and Impedance Measurements of UHF RFID Chips

TLDR

The paper presents a method to measure sensitivity and impedance of UHF RFID chips. The method uses an RFID tester with variable power and frequency together with a vector network analyzer, connects chips directly to standard 50‑Ω connectors without special matching, and measures sensitivity and threshold impedance in a fast, efficient way, applicable to various package types. Experimental results for NXP UCODE G2XM and Impinj Monza 2 chips in thin‑shrink small outline packages were obtained and verified with 50‑Ω matched assemblies.

Abstract

In this paper, we describe 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-Omega connectors allowing the sensitivity and threshold impedance to be measured directly in a fast and efficient way. We present experimental data for two UHF Gen2 chips (NXP UCODE G2XM and Impinj Monza 2) in thin-shrink small outline packages. The results have been verified using two chip assemblies matched to 50 Omega . This method can also be applied to chips in other packages: flip-chip, strap, etc.