Inkjet Printed Planar Coil Antenna Analysis for NFC Technology Applications

The aim of this paper is to examine the potential of inkjet printing technology for the fabrication of Near Field Communication (NFC) coil antennas. As inkjet printing technology enables deposition of a different number of layers, an accurate adjustment of the printed conductive tracks thickness is possible. As a consequence, input resistance and factor can be finely tuned as long as skin depth is not surpassed while keeping the same inductance levels. This allows the removal of the typical damping resistance present in current NFC inductors. A general methodology including design, simulation, fabrication, and measurement is presented for rectangular, planar-spiral inductors working at 13.56 MHz. Analytical formulas, computed numerical models, and measured results for antenna input impedance are compared. Reflection coefficient is designated as a figure of merit to analyze the correlation among them, which is found to be below −10 dB. The obtained results demonstrate the suitability of this technology in the fabrication of low cost, environmentally friendly NFC coils on flexible substrates.

[1]  Tae Sung Kim,et al.  Sintering and consolidation of silver nanoparticles printed on polyimide substrate films , 2009 .

[2]  Li Yang,et al.  Low Cost Inkjet-printing Paper-Based Modules for RFID Sensing and Wireless Applications , 2008, 2008 38th European Microwave Conference.

[3]  Jie Zhang,et al.  Fine-line conductor manufacturing using drop-on demand PZT printing technology , 2002 .

[4]  C. Paul.  Inductance: Loop and Partial , 2009 .

[5]  K. Jaakkola,et al.  Applicability of Metallic Nanoparticle Inks in RFID Applications , 2009, IEEE Transactions on Components and Packaging Technologies.

[6]  U. Schubert,et al.  Inkjet Printing of Narrow Conductive Tracks on Untreated Polymeric Substrates , 2008 .

[7]  김현상.  Method of controlling the mobile terminal , 2011 .

[8]  Michael Gebhart,et al.  Optimizing Design of Smaller Antennas for Proximity Transponders , 2010, 2010 Second International Workshop on Near Field Communication.

[9]  Martin Fischer,et al.  Fully integrated passive UHF RFID transponder IC with 16.7-μW minimum RF input power , 2003, IEEE J. Solid State Circuits.

[10]  J. Hu.  Overview of flexible electronics from ITRI's viewpoint , 2010, VTS.

[11]  Li Yang,et al.  Conductive Inkjet-Printed Antennas on Flexible Low-Cost Paper-Based Substrates for RFID and WSN Applications , 2009, IEEE Antennas and Propagation Magazine.

[12]  Jooho Moon,et al.  Highly Conductive Ink Jet Printed Films of Nanosilver Particles for Printable Electronics , 2005 .