The distribution of useful frequencies in polygraph sensor channels

Abstract

Purpose: to help other polygraph researchers better understand the distribution of energy across different frequencies in the standard six polygraph channels in common use. The channels shown will be pneumo, electrodermal (Axciton), cardio cuff pressure, movement sensor, and infrared plethesmo (Axciton). In all cases we use a zero phase high pass filter with a fourth order roll off . Unless otherwise noted, all frequency traces are kept with a constant gain to show their relative energy or strength content.