Multimode resonator and RFID tags using the same

摘要

Chipless RFID tags and a tag system are provided, wherein the stepped impedance higher-order mode resonator includes two sets of composite transmission lines each set having an equal line length and including a plurality of transmission lines each having a plurality of specific levels to which the transmission line characteristic impedance is assigned, the two sets of composite transmission lines each connected in series, the sets being connected at the center to form an electrically symmetrical configuration and wherein the chipless RFID tags and the tag system allow each of the codes to be assigned to each of the structures of the stepped impedance higher-order mode resonator, and allow each of those codes to be identified by detecting each of the combinations of the higher-order mode resonance frequencies that may be produced from each the structures of the resonator that corresponds to each of the codes that have been assigned.

主权项

1. A multimode resonator comprising:
two sets of composite transmission lines each set having an equal electric length and including “N” transmission lines (in which “N” refers to four or more positive integers) each having “m” specific discrete values for the transmission line characteristic impedance (in which “m” refers to two or more positive integers) and connected in series, said two sets of composite transmission lines being so connected at the center as to form a symmetrical electric circuit configuration and having opposite terminals one of which is an open-circuited end and the other of which is a short-circuited end, wherein an “N”th-order's higher-order mode resonance frequency is designated as the reference frequency fN and the line electric length is equal to 90 degrees.