The performance of a wide variety of RFID systems depends critically on: how efficiently energy is coupled to and from an electronically coded label; on how effectively it is used within the label; and sometimes on how effectively it is transformed from one form to another within the label. The paper considers the definition of appropriate coupling factors and quality factors which describe these processes, and their role in regulating system performance in the near and far fields of both linear and non-linear process based technologies. Calculations allowing feasibility estimates of some new process combinations on which some RFID systems may be based are presented.
Peter H. Cole,
"Coupling and quality factors in RFID", Proc. SPIE 4593, Design, Characterization, and Packaging for MEMS and Microelectronics II, (19 November 2001); doi: 10.1117/12.448865; https://doi.org/10.1117/12.448865