In this work, we have developed an empirical expression for the input impedance of a rectangular microstrip antenna by applying the curve fitting the experimental results. We can also determine from this formula the variations of the input impedance as a function of frequency and dielectric permittivity, respectively. The results obtained were compared with those published, and we are very sati...

Activities around applications of Electrical Bioimpedance Spectroscopy (EBIS) have proliferated in the past decade significantly. Most of these activities have been focused in the analysis of the EBIS measurements, which eventually might enable novel applications. In Body Composition Assessment (BCA), the most common analysis approach currently used in EBIS is based on the Cole function, which ...

Beneficial effects of nitroprusside infusion in heart failure are purportedly a result of decreased afterload through "impedance" reduction. To study the effect of nitroprusside on vascular factors that determine the total load opposing left ventricular ejection, the total aortic input impedance spectrum was examined in 12 patients with heart failure (cardiac index <2.0 liters/min per m(2) and ...

The aim of this study was to determine whether impedance values in children with various chronic respiratory complaints differed from those observed in symptom-free children. Respiratory impedance was measured using the forced oscillation technique in 1,776 Dutch children aged 6-12 yrs. In addition to the commonly used parameters of resistance and reactance, further impedance parameters were ob...

Does it make sense to make impedance spectroscopy in non-stationary conditions? And if yes, how should one analyze the results? The main goal of this work is to give a satisfactory answer to these two questions. Regarding the first question and according to the usual interpretation of the concept of impedance, the answer should be no, because impedance is not defined as timedependent and, there...

This study explored a novel method for measuring cerebrovascular impedance to quantify the relationship between pulsatile changes in cerebral blood flow (CBF) and arterial pressure. Arterial pressure in the internal or common carotid artery (applanation tonometry), CBF velocity in the middle cerebral artery (transcranial Doppler), and end-tidal CO(2) (capnography) were measured in six young (28...