A Passive Harmonic Tag for Humidity Sensing

<table>Simulated tag input power and received power by a harmonic tag and conventional tag using a free-space model (a) and using a two-slope model with <svg height="15" id="M79" style="vertical-align:-3.13504pt" version="1.1" viewbox="0 0 88.900002 15" width="88.900002" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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</svg> m. (b) The power-up threshold (−20 dBm) is also shown.</table>

International Journal of Antennas and Propagation

A Passive Harmonic Tag for Humidity Sensing

Figure 13