6-Analytical Model to Analyze the Impedance Features of Single and Multiple Inductor Loop in Inductive Couple Feed RFID Antenna

Radio Frequency Identification (RFID) is a wireless communication system that enable wireless data transfer. Global market of RFID is projected to be around 24.5 billion USD in 2020. Malaysia is now implementing RFID tolling system and it may be more applications in future. An RFID reader would read data or information on RFID tag by means of electromagnetic coupling or radio waves. The tag must able to capture the radio signal energy to turn on the RFID chip to communicate. The designed tag is subject to process variation and failures during mass production manufacturing. A direct connection may transfer energy of electrostatic discharge and damage the chip. Inductive coupling feed to an antenna allows a bare chip to be bonded to a loop and packaged to protect it during tag productions. However, a good coupling as well as impedance match should be taken into account during design process. This work focus on analytical studies on the impedance for single and multiple layers loop in inductive couple RFID tags. It is crucial as the demand for smaller tags required a smaller chip module to be placed on the inlays. It is expected that the analysis can shows correlation and deviation in theory and implementation of different loops in inductive couple tags.