A human performs a variety of skillful movements by adjusting dynamic characteristics of his or her musculoskeletal system according to a task involved. Such characteristics of human movements can be described by mechanical impedance parameters. If the regulation mechanism of human impedance properties during the task can be clarified and modeled, there is a possibility that human skillful stra...

The current source is a key component in bio-impedance measurement systems. The accuracy of the current source can be measured in terms of its output impedance together with other parameters, with certain applications demanding extremely high output impedance. This paper presents an investigation and comparison of different current source designs based on the Enhanced Howland circuit combined w...

Several studies [1,2] have shown the potential of EIT to estimate cardiovascular parameters. To achieve this goal, EIT devices have to deal with small impedance variations. As a consequence, the high value of the direct component (DC) of the bio-impedance signal becomes an issue in terms of analog to digital converter resolution. With this research, we aim at demonstrating that the DC of the si...

In this paper we design the low-power CMOS limiting amplifier using negative impedance, the purpose of using negative impedance is to increase the gain of the amplifier. low-power operations are also done using all the active elements. The LA was implemented in a standard CMOS 0.18um technology. This limiting amplifier is designed for the instrumentation(bio-medical) application. Gain of the am...

Bio-impedance Analysis had been used in the medical field and research with over 70 years. This technique enable a non-invasive and low-cost diagnosis of a wide range of cardiovascular pathology. It permits the access to impedance changes caused by pathophysiological processes in living tissue and allows to the diagnosis several vascular anomalies such as arterial and venous diseases (stenosis,...

Most bio-impedance spectroscopy (BIS) systems inject sinusoidal current with a variable frequency into a sample with a known geometry through a pair of electrodes. Adopting the so-called tetra-polar configuration, it measures induced voltage data on a separate pair of electrodes. Impedance spectra are plotted in a certain range of frequency. We found that its accuracy decreases at high frequenc...