原始名称记载: Northeastern University

Provided herein are methods and systems for subharmonic tags including a single antenna having a reactive input impedance and a set of lumped components coupled to the antenna, the lumped components having a frequency-dependent input impedance, wherein the frequency-dependent input impedance of the lumped components causes the coupled antenna and lumped components to resonate at both an input frequency of the subharmonic tag and at an output frequency of the subharmonic tag.