Loading...

Motion Artifact Detection, Chip Characterization, and a Multi-Lead BLE ECG System with Internal Memory Design

Mohammad Mahdi Moeini Manesh | 2025

102 Viewed
  1. Type of Document: M.Sc. Thesis
  2. Language: Farsi
  3. Document No: 58705 (05)
  4. University: Sharif University of Technology
  5. Department: Electrical Engineering
  6. Advisor(s): Fotowat Ahmadi, Ali
  7. Abstract:
  8. The aim of this research is to investigate the challenges of cardiac signal recording and to propose solutions for improving it. First, the function of the heart, the role of electrodes, and the process of generating an electrocardiogram (ECG) are explained. One of the most significant issues in ECG recording during patient movement is motion artifact, which makes interpreting the cardiac signal difficult. To study this problem, an experimental circuit was built, and approximately 60% correlation was observed between the electrode–tissue impedance (as an indicator of motion artifact) and the cardiac signal. In addition, a chip called TMCIA was characterized for the purpose of recording cardiac signals and electrode–tissue impedance, simultaneously. The results showed differential gains of 42 and 47dB, a CMRR greater than 75dB, and an input-referred noise of less than 60nV/√Hz. Experiments conducted on the human body also demonstrated that this chip can simultaneously record the cardiac signal and electrode–tissue impedance by injecting currents up to 200nA at a frequency of 1 kHz. This chip also employs techniques such as chopping and time-domain multiplexing, which respectively help suppress low-frequency amplifier noise and significantly reduce power consumption. The study then addresses the limitations of existing Holter devices, such as insufficient long-term recording capability and a limited number of leads. A new Holter device called Alpha is introduced, which has a small form factor and can continuously display six leads in real time on a mobile phone while simultaneously storing the data in its internal memory for three days. It is also shown that this device has the potential to support up to 3 weeks of recording
  9. Keywords:
  10. Electrocardiogram ; Electrode-Tissue Impedance ; Holter Monitor ; Motion Atrifact

 Digital Object List

 Bookmark

...see more