Design of a high signal to ratio electrical impedance plethysmograph

Author

Urso, Alessio ; Shanker, R. ; Szabo, Bela ; Wagner, William D.

Author_Institution

Dept. of Electr. & Comput. Eng., Florida Atlantic Univ., Boca Raton, FL, USA

fYear

1990

fDate

1-4 Apr 1990

Firstpage

1100

Abstract

The authors describe a high-sensitivity impedence plethysmograph for determining the blood pressure of pigeons. The method described can be used for the study of human atherosclerosis. An instrument which increases the signal-to-noise ratio, therefore increasing the sensitivity, was designed. The signal obtained from the subject being tested consists of an amplitude modulated waveform with an index of modulation on the order of 0.1%. This instrument reduces the carrier amplitude in the amplitude modulated (AM) waveform and amplifies the signal before demodulation. The AM signal is then demodulated and any DC offset present is balanced out. The result is an increase in the index of modulation and a higher signal-to-noise ratio at the output

Keywords

biological techniques and instruments; biomedical equipment; biomedical measurement; blood; electric impedance measurement; haemodynamics; pressure measurement; signal processing equipment; AM signal; AM waveform; DC offset; amplitude modulated waveform; blood pressure; carrier amplitude; electrical impedance plethysmograph; human atherosclerosis; pigeons; signal-to-noise ratio; Amplitude modulation; Atherosclerosis; Blood pressure; Demodulation; Humans; Impedance; Instruments; Signal design; Signal to noise ratio; Testing;

fLanguage

English

Publisher

ieee

Conference_Titel

Southeastcon '90. Proceedings., IEEE

Conference_Location

New Orleans, LA

Type

conf

DOI

10.1109/SECON.1990.117991

Filename

117991