Temporal multi-frequency encoding technique for chipless RFID applications

A novel temporal multi-frequency encoding technique based on group delay for chipless Radio Frequency Identification (RFID) tag is presented. Cascaded microstrip transmission line sections coupled at alternative ends (C-sections) are utilized to generate the tag Identification (ID). C-sections are dispersive structures, have a group delay maximum at different frequencies which is purely dependent on the length of the C-section. The proposed device is designed, prototyped and experimentally verified for 2 bit coding. The obtained results confirm the concept and its use in chipless RFID applications. Furthermore the transformation of the prototype into chipless tag using simulation results is also incorporated.