Fully Digital Low-Power Implementation of an Audio Front-End for Portable Applications

  • Gabriele MeoniEmail author
  • Luca Pilato
  • Gabriele Ciarpi
  • Alessandro Palla
  • Luca Fanucci
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 573)


This work presents a fully digital implementation of an audio front-end for portable applications developed in a low-power perspective. Such platform acquires audio samples through a four digital Pulse Digital Modulation (PDM) microphones array and implements two-channel (left and right) beamformers to perform speech enhancement. The system also features a low-power Voice Activity Detector (VAD) for the implementation of source localization or noise reduction algorithms. Finally, the processed data can be converted into a 16-bit resolution Pulse Code Modulation (PCM) format and then transmitted through a standard Integrated Interchip Sound (I2S) interface. The front-end has been implemented onboard a Microsemi IGLOO nano Field Programmable Gate Array (FPGA), reaching a power consumption of only 2.264 mW. The low-power architecture and the implemented functionalities make the system a promising front-end for audio speech portable applications.


Low-power digital architecture Low-power FPGA Digital signal processing Audio beamforming Voice activity detection 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Gabriele Meoni
    • 1
    Email author
  • Luca Pilato
    • 1
  • Gabriele Ciarpi
    • 1
  • Alessandro Palla
    • 1
  • Luca Fanucci
    • 1
  1. 1.Department of Information Engineering (DII)University of PisaPisaItaly

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