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Continuous monitoring of biochemical information is critical for health management. Hydrogel, a synthetic material that exhibits volumetric response to target stimuli, is an attractive material for such applications. However, wireless readout of the hydrogel's response over a longer distance, while maintaining the small sensor dimension has been challenging. In this work we present ferrogel-based wireless acousto-biochemical sensing system with small dimension (length: 7.5 mm, diameter: 2 mm) and long sensing distance (>10 cm). The sensor utilizes ferromagnetic hydrogel to convert pH to the change in resonance frequency; the wireless measurement is made through the RF signal emission under ultrasonic excitation.
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An Optical Wireless Temperature Sensor
This paper presents a wireless temperature sensor that uses a GaAs solar cell as a wireless transmitter of information. Transmission of information with a solar cell is possible by modulating the luminescent radiation emitted by the solar cell. This technique, dubbed Optical Frequency Identification or OFID, was recently reported in the literature and in this work is used to transmit temperature measurements wirelessly. The hardware design of an OFID temperature sensor tag and its corresponding reader is described. A prototype of the proposed sensor was built as a proof of concept. Experimental results demonstrate wireless data transmission at a distance of 1 m distance and at a bit rate of 1200 bps. The wireless temperature sensor has a maximum error of 0.39°C (after calibration) with respect to a high-precision temperature meter.
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- Award ID(s):
- 1809637
- PAR ID:
- 10189899
- Date Published:
- Journal Name:
- 2019 IEEE Sensors Conference
- Page Range / eLocation ID:
- 1 to 4
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/SENSORS43011.2019.8956813
