Effect of shape and surroundings on harmonic transponder performance

Harmonic transponders utilise two distinct, harmonically spaced frequencies to communicate with the reader device. For efficient performance, the transponder antenna needs to be properly matched at these frequencies. This work investigates how the transponder performance is affected when the shape of the transponder changes through bending or when the transponder is in the proximity of an object with varying material parameters. The obtained results show that the performance of the transponder is more affected by the properties of the object it is attached to. With different bending states, the harmonic response of the transponder does not change significantly, meaning that the design could be suitable for conformal applications.

[1]  M. Bouthinon,et al.  Passive Microwave Transposer, Frequency Doubler for Detecting the Avalanche Victims , 1980, 1980 10th European Microwave Conference.

[2]  M. Kivikoski,et al.  Effects of bending GPS antennas , 2006, 2006 Asia-Pacific Microwave Conference.

[3]  Ville Viikari,et al.  Review of passive wireless sensors utilizing the intermodulation communication , 2014, 2014 IEEE RFID Technology and Applications Conference (RFID-TA).

[4]  Janne Ilvonen,et al.  Harmonic Transponders: Performance and Challenges , 2015 .

[5]  R. Stephenson A and V , 1962, The British journal of ophthalmology.

[6]  Chi-Chih Chen,et al.  A Portable Low-Power Harmonic Radar System and Conformal Tag for Insect Tracking , 2008, IEEE Antennas and Wireless Propagation Letters.

[7]  Janne Ilvonen,et al.  Investigation on bendable mobile devices in the presence of the user , 2014, The 8th European Conference on Antennas and Propagation (EuCAP 2014).

[8]  Janne Ilvonen,et al.  Antenna Matching at Harmonic Frequencies to Complex Load Impedance , 2015, IEEE Antennas and Wireless Propagation Letters.

[9]  J. Grosinger,et al.  A bend transducer for backscatter RFID sensors , 2012, Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation.

[10]  W. Marsden I and J , 2012 .

[11]  B. Colpitts,et al.  Harmonic radar transceiver design: miniature tags for insect tracking , 2004, IEEE Transactions on Antennas and Propagation.

[12]  R. Valkonen,et al.  Effect of ground plane bending on mobile terminal antenna performance , 2013, 2013 7th European Conference on Antennas and Propagation (EuCAP).

[13]  Janne Ilvonen,et al.  On Design and Evaluation of Harmonic Transponders , 2015, IEEE Transactions on Antennas and Propagation.