Fractal-Shaped Metamaterial Absorbers for Multireflections Mitigation in the UHF Band

A Minkowski fractal geometry is proposed in this letter as miniaturized absorber cell suitable for multipath phenomena mitigation within the European RFID UHF band. The proposed structure is analyzed through the combined use of an equivalent transmission line model and method-of-moments-based full-wave simulations. Very high miniaturization capabilities (about 50% with respect to standard configurations) are demonstrated for an 868 MHz absorber unit cell, characterized by an absorptivity more than 99%, a good angular stability, and a very thin substrate (≤λ0/100). The proposed configuration is appealing for designing compact absorbers useful for multipath reduction in wireless systems operating on restricted indoor environments.

[1]  A. Borgia,et al.  Fractal Reflectarray Antennas: State of Art and New Opportunities , 2016 .

[2]  Desmond P. Taylor,et al.  A Statistical Model for Indoor Multipath Propagation , 2007 .

[3]  Antonio Raffo,et al.  Radial-Shaped Single Varactor-Tuned Phasing Line for Active Reflectarrays , 2016, IEEE Transactions on Antennas and Propagation.

[4]  Giuseppe Di Massa,et al.  Tunable Reflectarray Cell for Wide Angle Beam-Steering Radar Applications , 2013, J. Electr. Comput. Eng..

[5]  Francesca Venneri,et al.  Fractal Microwave Absorbers for Multipath Reduction in UHF-RFID Systems , 2017, WorldCIST.

[6]  Willie J Padilla,et al.  Perfect metamaterial absorber. , 2008, Physical review letters.

[7]  Filippo Costa,et al.  Low-Cost Metamaterial Absorbers for Sub-GHz Wireless Systems , 2014, IEEE Antennas and Wireless Propagation Letters.

[8]  Yoshinobu Okano,et al.  Development of Optically Transparent Ultrathin Microwave Absorber for Ultrahigh-Frequency RF Identification System , 2012, IEEE Transactions on Microwave Theory and Techniques.

[9]  Filippo Costa,et al.  Perfect metamaterial absorbers in the ultra-high frequency range , 2013, 2013 International Symposium on Electromagnetic Theory.

[10]  Willie J Padilla,et al.  Metamaterial Electromagnetic Wave Absorbers , 2012, Advanced materials.

[11]  S. Tretyakov,et al.  Simple and Accurate Analytical Model of Planar Grids and High-Impedance Surfaces Comprising Metal Strips or Patches , 2007, IEEE Transactions on Antennas and Propagation.

[12]  S. Costanzo,et al.  Miniaturized Fractal Reflectarray Element Using Fixed-Size Patch , 2014, IEEE Antennas and Wireless Propagation Letters.

[13]  Sandra Costanzo,et al.  Environmental Effects on the Performances of a UHF Passive Tag-Based Commercial RFID System , 2016, WorldCIST.

[14]  A. Lázaro,et al.  Radio Link Budgets for UHF RFID on Multipath Environments , 2009, IEEE Transactions on Antennas and Propagation.

[15]  F. Costa,et al.  A Circuit-Based Model for the Interpretation of Perfect Metamaterial Absorbers , 2013, IEEE Transactions on Antennas and Propagation.

[16]  Yang Yang,et al.  A Miniaturized Metamaterial Absorber for Ultrahigh-Frequency RFID System , 2017, IEEE Antennas and Wireless Propagation Letters.