Investigation on detection accuracy of RFID tags on back-to-back queuing objects

While the RFID technology is widely used for object identification, its application to detect sequence of multiple objects located close to each other in a limited area is challenging due to tag identification ambiguity. This paper presents an empirical study of multiple-tag detection accuracy when tags are attached to certificate recipients who make a back-to-back queue on a stage in a graduation ceremony. The investigation is done on three parameters; the distance between an RFID reader and tags, the interval between two consecutive recipients and the walking velocity. The experiment result shows that when the objects to be detected are far from the reader, the detection performance drops, resulting in higher missing rates but lower swapping. A short tag-tag interval triggers a high missing rate and a high swapping rate with a low duplication rate. The high tag velocity induces a high missing rate and a low duplication rate but no trend in the swapping rate.