Impedance measurement for balanced UHF RFID tag antennas
- Resource Type
- Conference
- Authors
- Zhu, Hailong; Ko, Y. C. Andrew; Ye, Terry T.
- Source
- 2010 IEEE Radio and Wireless Symposium (RWS) Radio and Wireless Symposium (RWS), 2010 IEEE. :128-131 Jan, 2010
- Subject
- Communication, Networking and Broadcast Technologies
Computing and Processing
Impedance measurement
RFID tags
UHF antennas
Dipole antennas
Antenna measurements
UHF measurements
Fixtures
Testing
Probes
Scattering parameters
radio frequency identification (RFID)
balanced antenna
network analyzer
de-embedding
mixed-mode S-parameter
- Language
- ISSN
- 2164-2958
2164-2974
Dipole antennas in UHF RFID tags are driven by differential signals; it is difficult to measure the antenna input impedance accurately using single-ended probes. Furthermore, the testing fixture used in the antenna measurement process also induces additional parasitic effects; accurate measurement cannot be achieved without taking the fixture impact into consideration. In this paper, we propose to characterize the dipole antenna's input impedance using mixed mode S-parameters, the testing fixture impact can also be quantified with port extension and de-embedding techniques. Experiments demonstrate that the proposed measurement method achieves very consistent results over UHF frequency band with very high accuracy.