A 2-bit chipless sensing tag based on dual mode resonators

This paper presents new type of dual mode sensor for dielectric characterization. The design uses the even mode of the resonator for measuring the dielectric constant of a sample under test. For the odd mode, two identification (ID) transmission lines are loaded such that we obtain four ID combinations (00, 01, 10, and 11). By proper design procedure, the even mode resonances are insensitive to the ID resonator loading, whereas the odd mode resonances are insensitive to the sample characteristics. The dielectric constant and loss tangent are successfully measured with this sensor.