A phase-based technique for discriminating tagged items moving through a UHF-RFID gate

A phase-based technique is presented for discriminating tagged items moving on a conveyor belt from other tagged items that are present in the scenario, when a UHF RFID gate is installed at a conveyor section. Indeed, tagged items (either static or randomly moving in the scenario) that are close to the reader antenna could be detected even if they are not on the conveyor (false positive readings). The classification procedure here proposed is based on some features that are extracted from a phase-based technique used to localize tags on a conveyor belt, which takes advantage of the fact that the tagged items move along a conveyor whose speed and path are both known a priori. Differently from other techniques that are used to solve the above misclassification issue, the proposed approach does not require multiple antennas.

[1]  Antti S. Toivonen.  Identifying and Controlling Stray Reads at RFID Gates , 2012 .

[2]  Markus Brandner,et al.  Experimental evaluation of RFID gate concepts , 2011, 2011 IEEE International Conference on RFID.

[3]  A. Baroni,et al.  Experimental validation of phase-based localization of UHF-RFID tags moving on a conveyor belt , 2013, 2013 IEEE Antennas and Propagation Society International Symposium (APSURSI).

[4]  P. Nepa,et al.  Location and Tracking of UHF-RFID Tags , 2011, 2011 IEEE-APS Topical Conference on Antennas and Propagation in Wireless Communications.

[5]  Fionn Murtagh,et al.  Cluster Dissection and Analysis: Theory, Fortran Programs, Examples. , 1986 .

[6]  George Roussos,et al.  Enabling RFID in retail , 2006, Computer.

[7]  Gary M. Gaukler.  Item-Level RFID in a Retail Supply Chain With Stock-Out-Based Substitution , 2011, IEEE Transactions on Industrial Informatics.

[8]  Yoshinori Oikawa.  Simulation evaluation of tag movement direction estimation methods in RFID gate systems , 2012, 2012 IEEE Radio and Wireless Symposium.

[9]  P. Nepa,et al.  Location and tracking of items moving on a conveyor belt and equipped with UHF-RFID tags , 2012, Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation.