Electrical and Computer Engineering, Materials Science and Engineering, Center for Nondestructive Evaluation (CNDE)
IEEE International Instrumentation and Measurement Technology Conference (I2MTC)
Link to Published Version
Journal or Book Title
2018 IEEE International Instrumentation and Measurement Technology Conference (I2MTC)
May 14-17, 2018
Nitrate efflux from agricultural lands mixes with surface streams and adversely affects both human health as well as aquatic life. Currently, there is a lack of low-cost, effective, real-time systems for monitoring ion concentration. In this work, a microwave resonant sensor is designed using an open-ended coaxial transmission line, which can be evanescently perturbed by a liquid sample, and a suitable coupling structure which allows transmission measurements. The sensor is developed to have high sensitivity at agriculturally relevant concentrations, low manufacturing costs, and small dimensions to be potentially field deployable. Finite Element Analysis simulations are carried out using ANSYS HFSS, employing complex permittivity data of aqueous solution samples with varying concentrations of nitrate, sulfate, and chloride ions. Appropriate functions are determined that model the correlations between resonant frequency and ion concentration, and discussion on the feasibility of the sensor for field deployment is presented.
Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
Roy, Subhanwit; Neihart, Nathan M.; and Bowler, Nicola, "Coaxial microwave resonant sensor design for monitoring ionic concentration in aqueous solutions" (2018). Materials Science and Engineering Conference Papers, Posters and Presentations. 46.