An Application of Electrical Filters to Spectrum Analysis

Abstract

   A method of spectrum analysis using electrical filters, that is, the band-pass sigma meter and the high-pass sigma meter, and their characteristics are investigated.
   It is found, from the results processed by the band-pass sigma meter, that the spectrum shows the one which is averaged for a fairly long time and smoothed. It is also found that this method is very useful and effective in deciding the peak frequency of the spectrum though the spectrum functions can not be obtained so accurately when the spectrum is not distributed in a relatively wide frequency range.
   This method of estimating an energy spectrum is applicable not only to laboratory data but also to field ones.
   It is shown by graphical calculation of the spectrum that the method of spectrum analysis using several high-pass sigma meters of which the transfer functions are the 4th order or more higher order is more proper than that using the band-pass sigma meter, in obtaining a spectrum accurately.