Title :
High precision Multifrequency Electrical Impedance Tomography System and Preliminary imaging results on saline tank
Author :
Xuetao, Shi ; Fusheng, You ; Feng, Fu ; Ruigang, Liu ; Xiuzhen, Dong
Author_Institution :
Dept. of Med. Electron. Eng., Fourth Mil. Med. Univ., Xi´´an
Abstract :
To establish a high precision data acquisition system for multi-frequency electrical impedance tomography (EIT), a series of methods were introduced. Those methods include building a driving signal with up to four frequency components to diminish the effect of the dynamic change of tissues resistivity, extracting the impedance information by a digital demodulator that can improve the SNR by 8 times. The system that established can work at a wide range from 1.6 kHz to 380 kHz. Its CMRR is 74 dB at 100 kHz. The output impedance of current source is 2 MOmega at that frequency. And measurement precision on a 100 ohm resistor is better than -80 dB in full bandwidth. Both the quasi-static and the dynamic imaging results based on a saline tank can reflect the resistivity changes inside the phantom clearly. Therefore, the system was competent in multifrequency EIT research work
Keywords :
bioelectric phenomena; biological tissues; data acquisition; electric impedance imaging; electrical resistivity; phantoms; 1.6 to 380 kHz; 100 ohm; 2 Mohm; CMRR; SNR; digital demodulator; dynamic imaging; high precision data acquisition system; high precision multifrequency electrical impedance tomography system; phantom; quasistatic imaging; saline tank; tissue resistivity; Bandwidth; Conductivity; Data acquisition; Data mining; Demodulation; Frequency; Imaging phantoms; Impedance; Resistors; Tomography; Dynamic image; Quasistatic image; data acquisition; electrical impedance tomography (EIT);
Conference_Titel :
Engineering in Medicine and Biology Society, 2005. IEEE-EMBS 2005. 27th Annual International Conference of the
Conference_Location :
Shanghai
Print_ISBN :
0-7803-8741-4
DOI :
10.1109/IEMBS.2005.1616714
