Improved heart rate variability signal analysis from the beat occurrence times according to the IPFM model

The heart rate variability (HRV) is an extended tool to analyze the mechani sms controlling the cardiovascular system. In this paper, the integral puls e frequency modulation model (IPFM) is assumed, It generates the beat occur rence times from a modulating signal, This signal is thought to represent t he autonomic nervous system action, mostly studied in its frequency compone nts. Different spectral estimation methods try to infer the modulating sign al characteristics from the available beat timing on the electrocardiogram signal. These methods estimate the spectrum through the heart period (HP) o r the heart rate (HR) signal, We introduce a new time domain HRV signal, th e Heart Timing (HT) signal, We demonstrate that this HT signal, in contrast with the HR or HP, makes it possible to recover an unbiased estimation of the modulating signal: spectra, In this estimation we avoid the spurious co mponents and the low-pass filtering effect generated when analyzing HR or H P.