Showing papers by "Yves Rolain published in 2022"
TL;DR: In this paper , a combination of a fan and speaker-based measurement apparatus that employs the forced oscillation technique (FOT) helps physicians to assess the current state of their patient's lungs.
Abstract: The number of patients suffering from asthma and chronic obstructive pulmonary disease (COPD) increases due to deteriorating air quality and smoking. A measurement technique known as the forced oscillation technique (FOT) helps physicians to assess the current state of their patient’s lungs. Measurement devices based on either fans or speakers have been developed in the past that can carry out this measurement, but their performance and/or robustness often fall short. This article proposes a combination of a fan- and speaker-based measurement apparatus that employs the FOT to help physicians diagnose patients with these diseases. First, we discuss the currently available measurement devices and their specific problems. Next, a fan-speaker hybrid measurement apparatus is proposed. This fan-speaker hybrid FOT measurement apparatus is then characterized and its performance is improved with a feed forward compensation. Finally, measurements on two test subjects with the proposed measurement apparatus are shown and discussed.
04 Apr 2022
TL;DR: In this paper , a local rational model is proposed to increase the precision of interpolated calibration methods with a low-order rational model over a shifting local frequency window, which is validated on a mm-wave one-port calibration example.
Abstract: Any measurement device needs to be calibrated in order to obtain accurate measurements. For RF systems, this calibration is closely tied to the considered excitation frequencies. If one wants to deviate from the original calibration frequencies, one has to redo the time-consuming calibration or resort to interpolation. This paper proposes to increase the precision of existing interpolated calibration methods with a local rational modelling technique. As the name suggests, this technique models the error coefficients with a low-order rational model over a shifting local frequency window. The proposed technique is validated on a mm-wave one-port calibration example.