Non-Invasive Microwave Sensors for Biomedical Applications: New Design Perspectives

Abstract

Abstract. The basic operation principles of non-invasive

Response Sharpening of Resonant Sensors for Potential Applications in Blood Glucose Monitoring

“…D IABETES is a serious chronic disease which can lead to various complications, such as heart and kidney problems, leg amputation, vision loss and nerve damage [1]. This disease occurs when the body fails to control blood glucose levels, and its incidence increases with the age of the population and the prevalence of obesity [2]. Consequently, as these two risk factors have increased in recent years, the aforementioned disease has also spread more throughout the world.…”

“…For example, resonant sensors are very common, and their basic principle is that a change in the glucose concentration leads to a shift in the resonant frequency. As representative of the work done in such a field, we mention the papers [2]- [11], where different kinds of microwave sensors have been studied. In [8], for example, two spatially separated ring resonators are considered to take into account the temperature dependence of the sensor; in [9], the sensor consists of four split ring resonators, and the data energy density is used to estimate the glucose concentration; in [10], a chipless tag is exploited and resonance shift up to 38 KHz is detected; in [11], both data collected in reflection and transmission mode are employed and compared.…”

“…The proposed method is first checked on synthetic data mimicking the resonant sensor response, and further validated on measured data collected by a microwave resonant sensor, properly designed for blood glucose monitoring, just located in contact to human fingers [2] [13] [14].…”

Electric Field and Dispersion Characteristic Calculations of Glass Tube Waveguides Filled with Biological Substances

“…The dependence of complex permittivity of various biomaterials upon frequency is often expressed in terms of the dielectric model of Debye, and its modifications double Debye, Cole-Cole, or multiply Cole-Cole [6][7][8]. There are measurements and simulations using the double Debye method in [6].…”

“…Debye formulas, Cole-Cole models, measured dielectric constant, and loss tangent dependencies on frequency in the 2.2-2.7 GHz frequency range for water solutions with different glucose concentrations are presented in [7].…”