Blood-Sugar Monitoring by Reflection of Millimeter Wave

Abstract

Diabetes mellitus has now emerged as a serious public health problem in Asia. To control blood glucose level, blood-sugar monitoring is necessary. Nevertheless non-invasive blood-sugar monitoring technique has not been in practical use. Complex permittivity of blood is very sensitive to the glucose concentration in microwaves. In this paper, a new technique is proposed to obtain blood glucose level using a resonant applicator non-invasively. It is found from in vivo measurement of reflection coefficient using the resonant applicator, blood glucose level can be obtained by measuring the value of reflection coefficient at the resonant frequency.

Influence of probe pressure when using MM‐wave open‐ended probe for diagnosis of the human skin

“…The large impact of probe pressure on the nail has in particular significance for high sensitivity measurements at the nail as proposed by Ref. 6.…”

Millimeter-Wave Tissue Diagnosis: The Most Promising Fields for Medical Applications

“…At the palm, the epidermis can reach thicknesses of up to 400 nm [92], [93], which should be considered if the fingertip is chosen as the measurement side. A resonant sensor with a resonance frequency of approximately 32 GHz has been suggested in [94], consisting of a resonating microfiber between a feeding coaxial probe and the patient's finger [Figure 3(a)]. The measurements showed a change in the return loss of 0.011 dB/mg glucose/dL at resonance frequency.…”

“…For the presented measurements, S11 was measured over a broad frequency range (90)(91)(92)(93)(94)(95)(96)(97)(98)(99)(100)(101)(102)(103)(104), and only the magnitude of S11 at single frequencies was evaluated; i.e., the phase information was not found to be needed, which significantly simplifies the necessary readout circuit of an integrated sensor solution. Furthermore, it is assumed that broadband measurement data are not necessary, but that a single or a few frequency points are sufficient.…”

“…Examples of millimeter-wave sensors for noninvasive blood glucose measurement: (a) a resonant sensor to be placed on the patient's finger for measurement (adapted from[94]) and (b) a microstrip line sensor: the characteristic impedance of the transmission line is altered by the blood vessel on top of the line depending on the blood glucose concentration. The different glucose concentrations can be read out as phase shifts…”

Detecting Vital Signs with Wearable Wireless Sensors

“…Another preliminary study was published recently on non-invasive measurement of BGL using millimetre-waves [ 28 , 29 ]. In the study, a metal fibre was connected to a waveguide and the return loss of the system measured by placing different glucose solutions as a load.…”