Reader, tags, radio frequency identification (RFID) system, and method thereof

摘要

A reader, tags, an RFID system, and a method of simultaneously identifying a plurality of tags having colliding reply signals and reducing the reading time. In the RFID system including a reader and plural tags assigned unique IDs, the reader stores a comparison code which identifies ID codes generated based on the unique IDs of the tags, and issues a query signal to the tags to inquire into the presence of the tags. In response to the received query signal, the tags generate the ID codes based on their unique IDs and sends the ID codes to the reader. The reader stores the received ID codes and identifies the responding tags by comparing the stored comparison code with the ID codes. When the ID codes are orthogonal, colliding reply signals can be resolved through a correlation technique.