TY - JOUR
T1 - A Compact, Passive Frequency-Hopping Harmonic Sensor Based on a Microfluidic Reconfigurable Dual-Band Antenna
AU - Zhu, Liang
AU - Farhat, Mohamed
AU - Chen, Yi-Chao
AU - Salama, Khaled N.
AU - Chen, Pai-Yen
N1 - KAUST Repository Item: Exported on 2020-10-01
PY - 2020
Y1 - 2020
N2 - We propose here a fully-passive wireless liquid sensor using a harmonic transponder, which comprises a dual-band microstrip antenna reconfigured by different types of liquids injected in a fluidic cavity. Different from traditional radio-frequency (RF) backscatter sensors, the proposed harmonic-transponder sensor (or harmonic sensor) receives frequency-hopped RF monotones and backscatters their second harmonics, with the peak frequency shifted by dielectric properties of liquid mixtures. This microstrip antenna has a hybrid-feed structure, of which an outer split-ring patch exhibits a narrow-band TM310 mode at the fundamental frequency (f0) and an inner elliptical patch displays a wideband resonance centered at the second-harmonic frequency (2f0), achieved with hybridization of TMe110 and TMo110 modes. In particular, the outer split-ring patch is loaded with a fluidic channel system to tune the resonance frequency of the TM310 mode (f0). We demonstrate that the type of liquid mixture filling in the fluidic cavity can be clearly perceived by reading the peak received signal strength indicator (RSSI) in the spectrum of second harmonics. Our results show the potential for deploying this passive wireless sensor in noisy environments that include clutters, multiple reflections, jamming, and crosstalks.
AB - We propose here a fully-passive wireless liquid sensor using a harmonic transponder, which comprises a dual-band microstrip antenna reconfigured by different types of liquids injected in a fluidic cavity. Different from traditional radio-frequency (RF) backscatter sensors, the proposed harmonic-transponder sensor (or harmonic sensor) receives frequency-hopped RF monotones and backscatters their second harmonics, with the peak frequency shifted by dielectric properties of liquid mixtures. This microstrip antenna has a hybrid-feed structure, of which an outer split-ring patch exhibits a narrow-band TM310 mode at the fundamental frequency (f0) and an inner elliptical patch displays a wideband resonance centered at the second-harmonic frequency (2f0), achieved with hybridization of TMe110 and TMo110 modes. In particular, the outer split-ring patch is loaded with a fluidic channel system to tune the resonance frequency of the TM310 mode (f0). We demonstrate that the type of liquid mixture filling in the fluidic cavity can be clearly perceived by reading the peak received signal strength indicator (RSSI) in the spectrum of second harmonics. Our results show the potential for deploying this passive wireless sensor in noisy environments that include clutters, multiple reflections, jamming, and crosstalks.
UR - http://hdl.handle.net/10754/663448
UR - https://ieeexplore.ieee.org/document/9110883/
U2 - 10.1109/JSEN.2020.3000778
DO - 10.1109/JSEN.2020.3000778
M3 - Article
SN - 2379-9153
SP - 1
EP - 1
JO - IEEE Sensors Journal
JF - IEEE Sensors Journal
ER -