T. Parve - Academia.edu (original) (raw)
Papers by T. Parve
Electronics and Electrical Engineering, 2011
A method for design of the switching mode lock-in bioimpedance measurement unit is proposed. The ... more A method for design of the switching mode lock-in bioimpedance measurement unit is proposed. The unit is foreseen to use in implantable medical devices for making medical experiments in vivo. The solution is aimed to lessen the errors caused due to sensitivity of the switching mode lock-in signal converters to the odd higher harmonics of an input signal. The applied method is similar to pulse width modulation (PWM), and it is oriented to achieve minimal complexity and low energy consumption.
An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the p... more An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the paper. The designed EB I-chip contains switched capacitor (SC) inphase and quadrature synchronous demodulators operating in the low f requency range up to 8 kHz, and which are f ollowed by the 5th order SC low pass f ilters (LPF) having a deep notch
Some key concepts of designing the lock-in signal converters for measurement of dynamic variation... more Some key concepts of designing the lock-in signal converters for measurement of dynamic variations of electrical bioimpedance (EBI) are discussed. ... The aim of design is to ensure effective rejection of additive disturbances, maintaining both, the adequate dynamic response, and required ...
The design and implementation of an instrument capable of simultaneously measuring bioimpedance o... more The design and implementation of an instrument capable of simultaneously measuring bioimpedance on four channels at eight frequencies at a reasonable cost required a novel approach. Eight microampere-level sinusoidal excitation current generators operating at frequencies from 100 Hz to 5 MHz are multiplexed to external electrodes within a biological sample, while impedance signals from four pairs of electrodes are processed within the instrument. Four 16-bit A/D converters digitize the four analog signals, followed by detection using an original method of non-uniform synchronous undersampling. Instrumentation control, data acquisition and display software were developed in the LabView 7.1 VI environment. The software can also be used to run virtual experiments using a computer model (digital phantom) of an organ to be studied. This is useful for model development, planning of experiments and for training. The instrument will be used to characterize cardiac function as well as to assess vascular and respiratory systems.
Using of chirp-type excitations for the fast broadband measurement and estimation of the complex ... more Using of chirp-type excitations for the fast broadband measurement and estimation of the complex bioimpedance is discussed in this paper. The proposed method includes cross-correlation of the excitation (reference) and response signals with a subsequent Fourier analysis of the obtained correlation function. It is shown that the phase response can be especially convenient for estimating of the state of a
An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the p... more An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the paper. The designed EB I-chip contains switched capacitor (SC) inphase and quadrature synchronous demodulators operating in the low f requency range up to 8 kHz, and which are f ollowed by the 5th order SC low pass f ilters (LPF) having a deep notch
![Research paper thumbnail of An implantable analyzer of bio-impedance dynamics: mixed signal approach [telemetric monitors]](https://attachments.academia-assets.com/43453660/thumbnails/1.jpg)
](IEEE Transactions on Instrumentation and Measurement, 2002
An on-chip implantable lock-in analyzer of variations of the electrical bio-impedance has been de... more An on-chip implantable lock-in analyzer of variations of the electrical bio-impedance has been designed, and pilot ASICs have been fabricated and tested. A mixed signal approach as the most suitable way for accomplishing a low-voltage and low-power ASIC for use in implantable devices for various biomedical applications is discussed in this paper.
2012 13th Biennial Baltic Electronics Conference, 2012
ABSTRACT In this paper the development of the electrical bioimpedance topic as a part of the trad... more ABSTRACT In this paper the development of the electrical bioimpedance topic as a part of the traditional master's course of Biomedical Electronics is discussed. A description of this part of the course and analysis of it is given together with explanations to the way of discussing the electrical properties of the biological objects, tissues and organs in the course. Discussion of measurement of the Electrical Bioimpedance, and of the electronic means for this purpose are also presented. All this is done in connection with the problematics of providing the students the e-learning facilities over the Internet.
2008 11th International Biennial Baltic Electronics Conference, 2008
In this paper, theoretical considerations and simulation results of a method for quick estimation... more In this paper, theoretical considerations and simulation results of a method for quick estimation of the bioimpedance (BI)vector over a wide range of excitation frequencies are discussed. This method uses a chirp signal with linearly modulated frequency for excitation. The response signal is processed using cross-correlation techniques together with following fast Fourier transform (FFT). As the result, the complex spectrum of the response signal is attained in the range of frequency, determined by the spread of chirp pulse. This spectrum characterizes the frequency response of the impedance under study.
2005 IEEE Instrumentationand Measurement Technology Conference Proceedings, 2005
ABSTRACT
Electronics and Electrical Engineering, 2011
A method for design of the switching mode lock-in bioimpedance measurement unit is proposed. The ... more A method for design of the switching mode lock-in bioimpedance measurement unit is proposed. The unit is foreseen to use in implantable medical devices for making medical experiments in vivo. The solution is aimed to lessen the errors caused due to sensitivity of the switching mode lock-in signal converters to the odd higher harmonics of an input signal. The applied method is similar to pulse width modulation (PWM), and it is oriented to achieve minimal complexity and low energy consumption.
An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the p... more An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the paper. The designed EB I-chip contains switched capacitor (SC) inphase and quadrature synchronous demodulators operating in the low f requency range up to 8 kHz, and which are f ollowed by the 5th order SC low pass f ilters (LPF) having a deep notch
Some key concepts of designing the lock-in signal converters for measurement of dynamic variation... more Some key concepts of designing the lock-in signal converters for measurement of dynamic variations of electrical bioimpedance (EBI) are discussed. ... The aim of design is to ensure effective rejection of additive disturbances, maintaining both, the adequate dynamic response, and required ...
The design and implementation of an instrument capable of simultaneously measuring bioimpedance o... more The design and implementation of an instrument capable of simultaneously measuring bioimpedance on four channels at eight frequencies at a reasonable cost required a novel approach. Eight microampere-level sinusoidal excitation current generators operating at frequencies from 100 Hz to 5 MHz are multiplexed to external electrodes within a biological sample, while impedance signals from four pairs of electrodes are processed within the instrument. Four 16-bit A/D converters digitize the four analog signals, followed by detection using an original method of non-uniform synchronous undersampling. Instrumentation control, data acquisition and display software were developed in the LabView 7.1 VI environment. The software can also be used to run virtual experiments using a computer model (digital phantom) of an organ to be studied. This is useful for model development, planning of experiments and for training. The instrument will be used to characterize cardiac function as well as to assess vascular and respiratory systems.
Using of chirp-type excitations for the fast broadband measurement and estimation of the complex ... more Using of chirp-type excitations for the fast broadband measurement and estimation of the complex bioimpedance is discussed in this paper. The proposed method includes cross-correlation of the excitation (reference) and response signals with a subsequent Fourier analysis of the obtained correlation function. It is shown that the phase response can be especially convenient for estimating of the state of a
An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the p... more An original ASIC f or electrical bio- impedance measurement (the EB I-chip) is described in the paper. The designed EB I-chip contains switched capacitor (SC) inphase and quadrature synchronous demodulators operating in the low f requency range up to 8 kHz, and which are f ollowed by the 5th order SC low pass f ilters (LPF) having a deep notch
IEEE Transactions on Instrumentation and Measurement, 2002
An on-chip implantable lock-in analyzer of variations of the electrical bio-impedance has been de... more An on-chip implantable lock-in analyzer of variations of the electrical bio-impedance has been designed, and pilot ASICs have been fabricated and tested. A mixed signal approach as the most suitable way for accomplishing a low-voltage and low-power ASIC for use in implantable devices for various biomedical applications is discussed in this paper.
2012 13th Biennial Baltic Electronics Conference, 2012
ABSTRACT In this paper the development of the electrical bioimpedance topic as a part of the trad... more ABSTRACT In this paper the development of the electrical bioimpedance topic as a part of the traditional master's course of Biomedical Electronics is discussed. A description of this part of the course and analysis of it is given together with explanations to the way of discussing the electrical properties of the biological objects, tissues and organs in the course. Discussion of measurement of the Electrical Bioimpedance, and of the electronic means for this purpose are also presented. All this is done in connection with the problematics of providing the students the e-learning facilities over the Internet.
2008 11th International Biennial Baltic Electronics Conference, 2008
In this paper, theoretical considerations and simulation results of a method for quick estimation... more In this paper, theoretical considerations and simulation results of a method for quick estimation of the bioimpedance (BI)vector over a wide range of excitation frequencies are discussed. This method uses a chirp signal with linearly modulated frequency for excitation. The response signal is processed using cross-correlation techniques together with following fast Fourier transform (FFT). As the result, the complex spectrum of the response signal is attained in the range of frequency, determined by the spread of chirp pulse. This spectrum characterizes the frequency response of the impedance under study.
2005 IEEE Instrumentationand Measurement Technology Conference Proceedings, 2005
ABSTRACT