Proximity Effects of Metallic Environments on High Frequency RFID Reader Antenna: Study and Applications

We study the proximity effects of metallic environments on the performance of high frequency (HF) radio frequency identification (RFID) reader antenna operating at 13.56 MHz. The performance of a typical HF RFID reader loop antenna in the proximity of various metal plate configurations is experimentally investigated in terms of resonant frequency, field intensity, and field distribution. The study shows that the presence of the metal plates shifts up the resonant frequency of the antenna and weakens its field intensity. The proximity effects are strongly dependent on the size of the metal plate, distance between the plate and the antenna as well as the orientation of the plate. Such effects greatly degrade the reading range and restrict the co-existence of HF RFID systems. A solution to alleviate the effects is to re-tune or co-design the reader antenna in proximity with the metallic objects based on the information from the study. As an example, a loop antenna is co-designed with a metal plate to configure a metal-backed loop antenna, and optimized for an RFID smart shelf system to restrain the interference and enhance the detection accuracy.

[1]  Robert L. Thomas.  A practical introduction to impedance matching , 1976 .

[2]  T. Sarkar,et al.  Using the matrix pencil method to estimate the parameters of a sum of complex exponentials , 1995 .

[3]  R. A. Burberry,et al.  Antenna problems in RFID systems , 1999 .

[4]  Klaus Finkenzeller,et al.  RFID Handbook: Radio-Frequency Identification Fundamentals and Applications , 2000 .

[5]  Valerie M. Thomas,et al.  Optimization of inductive RFID technology , 2001, Proceedings of the 2001 IEEE International Symposium on Electronics and the Environment. 2001 IEEE ISEE (Cat. No.01CH37190).

[6]  P. Raumonen,et al.  Folded dipole antenna near metal plate , 2003, IEEE Antennas and Propagation Society International Symposium. Digest. Held in conjunction with: USNC/CNC/URSI North American Radio Sci. Meeting (Cat. No.03CH37450).

[7]  J. Nielsen,et al.  Power spectral density of a UWB signal with discrete quantized pulse positions , 2003, Canadian Journal of Electrical and Computer Engineering.

[8]  Georgios B. Giannakis,et al.  Ultra-wideband communications: an idea whose time has come , 2003, 2003 4th IEEE Workshop on Signal Processing Advances in Wireless Communications - SPAWC 2003 (IEEE Cat. No.03EX689).

[9]  I. Pele,et al.  Simultaneous modeling of impedance and radiation pattern antenna for UWB pulse modulation , 2004, IEEE Antennas and Propagation Society Symposium, 2004..

[10]  M.Y.W. Chia,et al.  Considerations for source pulses and antennas in UWB radio systems , 2004, IEEE Transactions on Antennas and Propagation.

[11]  W.L. Stutzman,et al.  Compact antennas for UWB applications , 2003, IEEE Aerospace and Electronic Systems Magazine.

[12]  J. Landt,et al.  The history of RFID , 2005, IEEE Potentials.

[13]  K. Goto,et al.  A 13.56 MHz RFID device and software for mobile systems , 2005, Second IEEE Consumer Communications and Networking Conference, 2005. CCNC. 2005.

[14]  S. Licul,et al.  Unified frequency and time-domain antenna modeling and characterization , 2005, IEEE Transactions on Antennas and Propagation.

[15]  Daniel M. Dobkin,et al.  Environmental Effects on RFID Tag Antennas , 2005, IEEE MTT-S International Microwave Symposium Digest, 2005..

[16]  Werner Wiesbeck,et al.  EURASIP Journal on Applied Signal Processing 2005:3, 296–305 c ○ 2005 Hindawi Publishing Corporation Influence of the Antennas on the Ultra-Wideband Transmission , 2002 .

[17]  Oliver Chiu-sing Choy,et al.  Adiabatic Smart Card , 2006, APCCAS 2006 - 2006 IEEE Asia Pacific Conference on Circuits and Systems.

[18]  B. Kippelen,et al.  RF Tag Antenna Performance on Various Materials Using Radio Link Budgets , 2006, IEEE Antennas and Wireless Propagation Letters.

[19]  Roy Want,et al.  An introduction to RFID technology , 2006, IEEE Pervasive Computing.

[20]  T.-P. Vuong,et al.  Realistic modeling of antennas for ultra wide band systems , 2006, 2006 IEEE Radio and Wireless Symposium.