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Title: Passive impedance-loaded surface acoustic wave (SAW) sensor for soil condition monitoring
This paper presents an innovative system to monitor the physical soil conditions needed for modern agriculture. The current technique to measure soil properties relies on taking samples from place to place and takes them for laboratory testing. To build up and monitor a data-based system for a large area, such a method is costly and time-consuming. This paper reported our recent work on the development of a passive impedance-loaded surface acoustic wave (SAW) sensor for a low-cost soil condition monitoring system. The SAW sensor will eventually be connected to an antenna and a impedance-based sensor for autonomous soil nutrient sensing. In this research, first, the coupling-of-modes (COM) analysis was performed to simulate the SAW device. The sensors were fabricated with E-beam lithography techniques and tested with different external load resistances. We investigated how the sensor signal changed with the external resistance loading. The experimental results were verified by comparing them with simulation results.  more » « less
Award ID(s):
1841558
PAR ID:
10294700
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Proc. ASME. IMECE2020
Volume:
13
Page Range / eLocation ID:
V013T13A009
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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