Adaptive Sampling for Ultra-Low-Power Electrocardiogram (ECG) Readouts

  • Venkata Rajesh Pamula
  • Chris Van Hoof
  • Marian Verhelst
Part of the Analog Circuits and Signal Processing book series (ACSP)


Adaptive sampling is introduced as an early data rate reduction technique for ultra-low-power electrocardiogram (ECG) readouts in this chapter. The proposed adaptive sampling technique relies on detection of local bandwidth (BW) of the ECG signal and altering the sampling frequency. Compared to other ECG data rate reduction approaches such as discrete wavelet transform (DWT) and compressive sampling (CS), adaptive sampling is shown to introduce less distortion as accessed through percentage root mean square distortion (PRD) for similar compression ratio (CR). Efficient task partitioning between analog and digital domains, from energetics stand point, in realizing the adaptive sampling controller (ASC) is presented. Systematic design approaches are introduced in realizing the ultra-low-power analog ASC that dissipates only 30.6 nW of power and achieving a dynamic range (DR) of 47.2 dB. The implemented ASC chip enables up to 8 × compression of the ECG signal, while completely preserving the morphology of the QRS complexes which is crucial for accurate heart rate (HR) estimation.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Venkata Rajesh Pamula
    • 1
  • Chris Van Hoof
    • 1
  • Marian Verhelst
    • 2
  1. 1.imecLeuvenBelgium
  2. 2.KU Leuven ESAT-MICASLeuvenBelgium

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