Journal of Biomedical Engineering Research (대한의용생체공학회:의공학회지)

The Korean Society of Medical and Biological Engineering (대한의용생체공학회)
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Multi-Frequency Electrical Impedance Tomography System

다주파수 임피던스 단층촬영 시스템

  • Oh, Tong-In (Department of Biomedical Engineering College of Electronics and Information, Kyung Hee University) ;
  • Cho, Seong-Phil (Department of Biomedical Engineering College of Electronics and Information, Kyung Hee University) ;
  • Kim, Sang-Min (Department of Biomedical Engineering College of Electronics and Information, Kyung Hee University) ;
  • Koo, Hwan (Department of Biomedical Engineering College of Electronics and Information, Kyung Hee University) ;
  • Woo, Eung-Je (Department of Biomedical Engineering College of Electronics and Information, Kyung Hee University)
  • 오동인 (경희대학교 전자정보대학 동서의료공학과) ;
  • 조성필 (경희대학교 전자정보대학 동서의료공학과) ;
  • 김상민 (경희대학교 전자정보대학 동서의료공학과) ;
  • 구환 (경희대학교 전자정보대학 동서의료공학과) ;
  • 우응제 (경희대학교 전자정보대학 동서의료공학과)
  • Published : 2007.02.28
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Abstract

We have developed a multi-channel, multi-frequency EIT system with operating frequency of 10Hz to 500KHz. The number of digital voltmeters using phase-sensitive demodulation can be varied from 8 to 64 and we found that 16 and 32-channels are most practical. This paper describes the design, implementation, and construction of 16 and 32-channel systems. The performance of the system was thoroughly tested and we found that CMRR of the developed voltmeter is about 85dB with $100{\Omega}$ unbalancing series resistor. The SNR is greater than 99.6dB and the output impedance of the constant current source is $1{\Omega}W$ at least for all frequencies. Imaging experiments using a banana with frequency-dependent conductivity and permittivity show that frequency-difference imaging is possible using the developed system. Future works of animal and human experiments are discussed.

Keywords

References

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