8 January 1996 Noise suppression and correction of laser Doppler blood flow spectra after high-pass filtering
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Laser Doppler flowmetry (LDF) is a method that can be used for measuring blood flow changes in the microcirculation. We have contributed to the development of a new device for LDF, based on digital signal processing. A method for correcting the disregarding of frequency components was developed, by approximating the noise-free Doppler spectrum with an exponential shape. The frequency components from 40 kHz to 50 kHz can be used to correct for white noise. We introduced variable resistors for the case common mode components from both detectors have different magnitudes. However, after adjustment we found that noise may still be present. We have observed, that cutting off at 150 Hz suppresses many noise contributions and still provides sufficient Doppler information. For the transfer of a moment calculated from 150 Hz - 20 kHz into 0 - infinity Hz, the correction method mentioned above can be applied.
© (1996) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
K. J. Wierda, K. J. Wierda, Reindert Graaff, Reindert Graaff, R. R. van Someren, R. R. van Someren, Frits F. M. de Mul, Frits F. M. de Mul, B. Leerkotte, B. Leerkotte, Jan Greve, Jan Greve, "Noise suppression and correction of laser Doppler blood flow spectra after high-pass filtering", Proc. SPIE 2629, Biomedical Optoelectronics in Clinical Chemistry and Biotechnology, (8 January 1996); doi: 10.1117/12.229525; https://doi.org/10.1117/12.229525

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