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Coupling-independent, Real-time Wireless Resistive Sensing through Nonlinear PT-symmetry

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 Added by George Alexopoulos
 Publication date 2020
  fields Physics
and research's language is English




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We report the realization of coupling-independent, robust wireless sensing of fully-passive resistive sensors. PT-symmetric operation obviates sweeping, permitting real-time, single-point sensing. Self-oscillation is achieved through a fast-settling nonlinearity whose voltage amplitude is proportional to the sensors resistance. These advances markedly simplify the reader. A dual time-scale theoretical framework generalizes system analysis to arbitrary operating conditions and a correction strategy reduces errors due to detuning from PT-symmetric conditions by an order of magnitude.



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