Telecardiology under resource constraint: Low-complexity compact representation of ECG

Compact, yet faithful, representation of ECG signals to meet bandwidth and power constraints remains central to successful telecardiology, primarily in infrastructure-deficient areas. Towards practical realization, we seek desired compactness in the class of low-complexity transform representations. A typical ECG signal consists of a strong rhythmic (low-pass) component, with compact Fourier transform representation, and temporally localized (high-pass) features, efficiently representedby wavelet transform. Accordingly, we propose a compact representation consisting of suitable Fourier and wavelet coefficients. As computation of such coefficients is at most O(n log n), the proposed representation inherits the desired low complexity. Our method achieves targeted representation accuracy using fewer transform coefficients compared to the well-known fixed transform representations.