Time-frequency analysis of biological matter using short-time chirp excitation

In this paper, using of short-time chirp excitation for the bio-impedance measurement is discussed. The short-time chirp waveforms have at least two advantages. First, flat and wideband amplitude spectrum together with shortness of signal enable fast and adequate estimation of the object under study. Second, low power consumption with more than 90% concentration of the generated excitation energy into the desired bandwidth make such kind of excitation signals especially suitable for applying in implantable and wearable devices of impedance spectroscopy. The appropriate measurement system incorporates matched filtering of the response signal with following spectral analysis to locate small deviation of the actual bio-impedance spectrum from the reference spectrum.