Work

One-Port Tapered Rectangular Waveguide Microwave Permittivity Sensor

Year: 2025

Type: article

Abstract: This work presents a novel one-port microwave permittivity sensor. The sensor is formed by a non-uniform longitudinal section rectangular waveguide (RW) and makes use of the group delay of the reflected signal at its input as sensing magnitude. With the proposed sensor it is possible to measure the relative permittivity of low-loss dielectrics filling the waveguide. The theoretical background explaining the behavior of the sensor is given, along with expressions for the sensor sensitivity as a function of its geometrical dimensions. Guidelines are provided for designing the proposed sensor structure depending on the targeted range of material permittivities and the desired sensing frequency bandwidth. In order to verify the correct operation of the suggested sensor scheme, a proof-of-concept tapered RW (TRW) one-port sensor has been fabricated to measure relative permittivities between 3.5 and 6.5, for a frequency span from 4.8 GHz to 5.8 GHz. The implementation includes a microstrip to TRW transition for the determination of the dielectric permittivity of different low-loss materials under test.

Source: IEEE Sensors Journal

DOI: 10.1109/jsen.2025.3603743

Authors: Paula Viudes, Germán Torregrosa-Penalva, Enrique Bronchalo, Héctor García-Martínez

Institution: Universitat de Miguel Hernández d'Elx

Language: English

Topic: Microwave and Dielectric Measurement Techniques

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $2,645

Funders: Generalitat Valenciana, Ministerio de Educación y Cultura, Agencia Estatal de Investigación