Impedance analyser module for EIT and spectroscopy using undersampling.


:In this paper we present the concept, the design and the test procedure for a DSP-based high-precision and high-performance wide-band (up to 10 MHz) bioimpedance analyser module for application in EIT or bioimpedance spectroscopy. The module implements a digital concept with appropriate signal conditioning hardware for voltage and current measurement, early signal digitization and subsequent digital signal processing in order to calculate the components of impedance (or admittance). At low frequencies, the module utilizes the conventional direct conversion method, whereas at high frequencies the undersampling technique is used. The advantages of the described system are the following: (a) the frequency range is extended to higher frequencies, (b) the number of data sampled per time interval is significantly reduced, and (c) the current consumption and the costs of the ADCs can be significantly reduced. The validation procedure is performed by comparing the measured and theoretical values of the magnitude and the phase of the impedance for a commonly used tissue model. The module offers an accuracy of better than 0.012% for the magnitude of impedance and better than 0.02 degrees for the phase.


Physiol Meas


Dudykevych T,Gersing E,Thiel F,Hellige G




Has Abstract


2001-02-01 00:00:00












  • AASM standards of practice compliant validation of actigraphic sleep analysis from SOMNOwatch™ versus polysomnographic sleep diagnostics shows high conformity also among subjects with sleep disordered breathing.

    abstract::In recent AASM practice, parameter actimetry is cited to measure total sleep time in obstructive sleep apnoea patients, when polysomnography is not available. An actigraph was therefore compared to polysomnographic data in 28 subjects with known sleep disordered breathing. Total sleep time (TST), sleep period time (SP...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Dick R,Penzel T,Fietze I,Partinen M,Hein H,Schulz J

    更新日期:2010-12-01 00:00:00

  • Effects of awareness and nociception on heart rate variability during general anaesthesia.

    abstract::During anaesthesia awareness and nociception are serious complications that may further lead to haemodynamic instability. Specific monitoring of depth of hypnosis and depth of analgesia based on heart rate variability (HRV) analysis is eligible to improve patient safety and reduce efforts in post-operative care. Conse...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Huhle R,Burghardt M,Zaunseder S,Wessel N,Koch T,Malberg H,Heller AR

    更新日期:2012-02-01 00:00:00

  • Endocardial center motion for quantification of left ventricular discoordination in heart failure using cine MRI.

    abstract:OBJECTIVE:To compare a novel cardiovascular magnetic resonance technique for the assessment of left ventricular (LV) mechanical discoordination by characterizing the endocardial center motion (ECM) in short-axis cine MRI in healthy volunteers and heart failure patients with left bundle branch block (HF-LBBB). APPROACH...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Saporito S,Houthuizen P,Aben JMM,Westenberg JJM,van Den Bosch HCM,van Assen HC,Mischi M

    更新日期:2018-02-28 00:00:00

  • An analytic solution to the homogeneous EIT problem on the 2D disk and its application to estimation of electrode contact impedances.

    abstract::An analytic solution of the potential distribution on a 2D homogeneous disk for electrical impedance tomography under the complete electrode model is expressed via an infinite system of linear equations. For the shunt electrode model with two electrodes, our solution coincides with the previously derived solution expr...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Demidenko E

    更新日期:2011-09-01 00:00:00

  • Real time impedance plots with arbitrary frequency components.

    abstract::Temporal changes in the impedance spectra of bioelectrodes in contact with skin provide useful data for comparisons between differing electrode materials and skin preparation methods. Traditional impedance measuring systems employ swept frequency methods which will distort results in the impedance spectra of a sample ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Searle A,Kirkup L

    更新日期:1999-02-01 00:00:00

  • Early prediction of unexplained syncope by support vector machines.

    abstract::The goal of the present study was to develop and evaluate a new method for the prediction of unexplained syncope occurrences. Diagnosis of syncope is currently based on the reproduction of symptoms in combination with hypotension and bradycardia induced by a 45 min 60-70 degrees head-upright tilt test (HUTT). The main...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Schang D,Feuilloy M,Plantier G,Fortrat JO,Nicolas P

    更新日期:2007-02-01 00:00:00

  • Effect of body mass index (BMI) on estimation of extracellular volume (ECV) in hemodialysis (HD) patients using segmental and whole body bioimpedance analysis.

    abstract::The aim of the study was to investigate whether body mass index (BMI) influences the estimation of extracellular volume (ECV) in hemodialysis (HD) patients when using segmental bioimpedance analysis (SBIA) compared to wrist-to-ankle bioimpedance analysis (WBIA) during HD with ultrafiltration (UF). Twenty five HD patie...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Carter M,Morris AT,Zhu F,Zaluska W,Levin NW

    更新日期:2005-04-01 00:00:00

  • Fetal QRS detection and heart rate estimation: a wavelet-based approach.

    abstract::Fetal heart rate monitoring is used for pregnancy surveillance in obstetric units all over the world but in spite of recent advances in analysis methods, there are still inherent technical limitations that bound its contribution to the improvement of perinatal indicators. In this work, a previously published wavelet t...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Almeida R,Gonçalves H,Bernardes J,Rocha AP

    更新日期:2014-08-01 00:00:00

  • Electrical impedance myography at frequencies up to 2 MHz.

    abstract::Extension of the frequency range of electrical impedance myography (EIM) to 2 MHz discloses a major rise in the reactance of muscle above 3-500 kHz, together with a slow decrease in the resistance consonant with the Kramers-Kronig relations. This 'upturn' phenomenon is found when the distant current electrode configur...

    journal_title:Physiological measurement

    pub_type: 临床试验,杂志文章


    authors: Shiffman CA,Kashuri H,Aaron R

    更新日期:2008-06-01 00:00:00

  • Video rate electrical impedance tomography of vascular changes: preclinical development.

    abstract::Peripheral vasculature disease is strongly correlated with cardiovascular-associated mortality. Monitoring circulation health, especially in the peripheral limbs, is vital to detecting clinically significant disease at a stage when it can still be addressed through medical intervention. Electrical impedance tomography...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Halter R,Hartov A,Paulsen K

    更新日期:2008-03-01 00:00:00

  • Wearable sensors for patient-specific boundary shape estimation to improve the forward model for electrical impedance tomography (EIT) of neonatal lung function.

    abstract::Electrical impedance tomography (EIT) could be significantly advantageous to continuous monitoring of lung development in newborn and, in particular, preterm infants as it is non-invasive and safe to use within the intensive care unit. It has been demonstrated that accurate boundary form of the forward model is import...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Khor JM,Tizzard A,Demosthenous A,Bayford R

    更新日期:2014-06-01 00:00:00

  • Fractal analysis of foetal heart rate variability.

    abstract::Current methods for analysing foetal heart rate (FHR) patterns have yet to meet their full potential in the recognition of hypoxia in the foetus. Following the recent suggestion that fractal analysis can be applied to FHR recordings, the current paper describes a method for distinguishing two simultaneous fractal dime...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Gough NA

    更新日期:1993-08-01 00:00:00

  • Effects of muscle injury severity on localized bioimpedance measurements.

    abstract::Muscle injuries in the lower limb are common among professional football players. Classification is made according to severity and is diagnosed with radiological assessment as: grade I (minor strain or minor injury), grade II (partial rupture, moderate injury) and grade III (complete rupture, severe injury). Tetrapola...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Nescolarde L,Yanguas J,Lukaski H,Alomar X,Rosell-Ferrer J,Rodas G

    更新日期:2015-01-01 00:00:00

  • Solving the forward problem in electrical impedance tomography for the human head using IDEAS (integrated design engineering analysis software), a finite element modelling tool.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Bayford RH,Gibson A,Tizzard A,Tidswell T,Holder DS

    更新日期:2001-02-01 00:00:00

  • Improved ultrasound transducer positioning by fetal heart location estimation during Doppler based heart rate measurements.

    abstract:OBJECTIVE:Doppler ultrasound (US) is the most commonly applied method to measure the fetal heart rate (fHR). When the fetal heart is not properly located within the ultrasonic beam, fHR measurements often fail. As a consequence, clinical staff need to reposition the US transducer on the maternal abdomen, which can be a...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Hamelmann P,Vullings R,Schmitt L,Kolen AF,Mischi M,van Laar JOEH,Bergmans JWM

    更新日期:2017-09-21 00:00:00

  • Electroencephalogram classification in motor-imagery brain-computer interface applications based on double-constraint nonnegative matrix factorization.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Su J,Yang Z,Yan W,Sun W

    更新日期:2020-08-11 00:00:00

  • Cardiorespiratory coupling in young healthy subjects.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Sobiech T,Buchner T,Krzesiński P,Gielerak G

    更新日期:2017-11-30 00:00:00

  • Quantitative description of the 3D regional mechanics of the left atrium using cardiac magnetic resonance imaging.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Kuklik P,Molaee P,Podziemski P,Ganesan AN,Brooks AG,Worthley SG,Sanders P

    更新日期:2014-05-01 00:00:00

  • Characterization of cardiorespiratory phase synchronization and directionality in late premature and full term infants.

    abstract:OBJECTIVE:Though the mutual influence of cardiovascular and respiratory rhythms in healthy newborns has been documented, its full characterization is still pending. In general, the activity of many physiological subsystems has a well-expressed rhythmic character, and often an interdependency between physiological rhyth...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Lucchini M,Pini N,Fifer WP,Burtchen N,Signorini MG

    更新日期:2018-06-19 00:00:00

  • New porcine test-model reveals remarkable differences between algorithms for spectrophotometrical haemoglobin saturation measurements with VLS.

    abstract:UNLABELLED:The study created an 'ex vivo' model to test different algorithms for measurements of mucosal haemoglobin saturation with visible light spectrophotometry (VLS). The model allowed comparison between algorithms, but it also allowed comparison with co-oximetry using a 'gold standard' method. This has not been d...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Gade J,Greisen G

    更新日期:2016-09-01 00:00:00

  • PET(CO2) measurement and feature extraction of capnogram signals for extubation outcomes from mechanical ventilation.

    abstract::Capnography is a continuous and noninvasive method for carbon dioxide (CO2) measurement, and it has become the standard of care for basic respiratory monitoring for intubated patients in the intensive care unit. In addition, it has been used to adjust ventilatory parameters during mechanical ventilation (MV). However,...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Rasera CC,Gewehr PM,Domingues AM

    更新日期:2015-02-01 00:00:00

  • A shape-based quality evaluation and reconstruction method for electrical impedance tomography.

    abstract::Linear methods of reconstruction play an important role in medical electrical impedance tomography (EIT) and there is a wide variety of algorithms based on several assumptions. With the Graz consensus reconstruction algorithm for EIT (GREIT), a novel linear reconstruction algorithm as well as a standardized framework ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Antink CH,Pikkemaat R,Malmivuo J,Leonhardt S

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  • Association between RR interval and high-frequency heart rate variability acquired during short-term, resting recordings with free and paced breathing.

    abstract::High-frequency (HF) oscillations in RR interval from 0.15-0.40 Hz are widely accepted as a measure of cardiac vagal outflow but the HF/RR relationship appears complex, particularly with longer RR intervals. The aim of this study was to evaluate the HF/RR interval relationship during free and paced breathing. HF power ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Sandercock G,Gladwell V,Dawson S,Nunan D,Brodie D,Beneke R

    更新日期:2008-07-01 00:00:00

  • Fetal motion estimation from noninvasive cardiac signal recordings.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Biglari H,Sameni R

    更新日期:2016-11-01 00:00:00

  • Recognition of elementary arm movements using orientation of a tri-axial accelerometer located near the wrist.

    abstract::In this paper we present a method for recognising three fundamental movements of the human arm (reach and retrieve, lift cup to mouth, rotation of the arm) by determining the orientation of a tri-axial accelerometer located near the wrist. Our objective is to detect the occurrence of such movements performed with the ...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Biswas D,Corda D,Baldus G,Cranny A,Maharatna K,Achner J,Klemke J,Jöbges M,Ortmann S

    更新日期:2014-09-01 00:00:00

  • A comparison of technologies used for estimation of body temperature.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Mangat J,Standley T,Prevost A,Vasconcelos J,White P

    更新日期:2010-09-01 00:00:00

  • A method for comparative evaluation of EIT algorithms using a standard data set.

    abstract::The point spread function (PSF) is the most widely used tool for quantifying the spatial resolution of imaging systems. However, prerequisites for the proper use of this tool are linearity and space invariance. Because EIT is non-linear it is only possible to compare different reconstruction algorithms using a standar...

    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Ider YZ,Eyüboğlu BM,Kuzuoğlu M,Leblebïcïoğlu K,Baysal U,Cağlar BK,Bïrgül O

    更新日期:1995-08-01 00:00:00

  • PaCO2 measurement in cerebral haemodynamics: face mask or nasal cannulae?

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Minhas JS,Robinson T,Panerai R

    更新日期:2017-06-22 00:00:00

  • Patient examinations using electrical impedance tomography--sources of interference in the intensive care unit.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Frerichs I,Pulletz S,Elke G,Gawelczyk B,Frerichs A,Weiler N

    更新日期:2011-12-01 00:00:00

  • Esophageal temperature monitoring during radiofrequency catheter ablation: experimental study based on an agar phantom model.

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    journal_title:Physiological measurement

    pub_type: 杂志文章


    authors: Rodríguez I,Lequerica JL,Berjano EJ,Herrero M,Hornero F

    更新日期:2007-05-01 00:00:00