A Time-Frequency HRV Processor Using Windowed Lomb Periodogram

Abstract

In this paper, a system for time-frequency analysis of heart rate variability (HRV) using windowed Lomb periodogram is proposed. The system is designed with considerations in SOC implementation for portable applications. Time-frequency analysis of HRV is achieved through a de-normalized Lomb periodogram with a sliding window configuration. The Lomb time-frequency distribution (TFD) is suited for power spectral density (PSD) analysis of unevenly spaced data and has been applied to the analysis of heart rate variability. The system has been implemented in hardware as an HRV processor and verified on FPGA. Artificial heart rate was used to evaluate the system as well as data from the MIT-BIH arrhythmia database and real EKG data. Simulations show that the proposed Lomb TFD is able to achieve better frequency resolution than short-time Fourier transform of the same hardware size.