METHOD AND APPARATUS FOR DETERMINING THE DIRECTION OF MOVEMENT OF RFID TAGS AND FOR CREATING CONSTANT-WIDTH INTERROGATION ZONES

摘要

A method and apparatus for creating one-sided interrogation zones in a radio frequency identification systems. A method and apparatus for determining the direction of movement of tagged items that pass by an RFID reader. A method and apparatus for combining one-sided interrogation zones of two or more antenna arrays (103 and 104) to create an interrogation zone that maintains its width over a large range of distances in a radio frequency identification systems.