'Institute of Electrical and Electronics Engineers (IEEE)'
Doi
Abstract
A new phase-based technique for localization and
tracking of items moving along a conveyor belt and equipped with
ultrahigh frequency-radio frequency identification (UHF-RFID)
tags is described and validated here. The technique is based on
a synthetic-array approach that takes advantage of the fact that
the tagged items move along a conveyor belt whose speed and
path are known apriori. In this framework, a joint use is done
of synthetic-array radar principles, knowledge-based processing,
and efficient exploitation of the reader-tag communication signal.
The technique can be easily implemented in any conventional
reader based on an in-phase and quadrature receiver and it does
not require any modification of the reader antenna configurations
usually adopted in UHF-RFID portals. Numerical results are used
to investigate the performance analysis of such methods, and
also to furnish system design guidelines. Finally, the localization
capability is also demonstrated through a measurement campaign
in a real conveyor belt scenario, showing that a centimeter-order
accuracy in the tag position estimation can be achieved even in
a rich multipath environment
