Comparison and Implementation of Variable Fractional Delay Filters for Wideband Digital Beamforming

  • Gian Carlo Cardarilli
  • Daniele GiardinoEmail author
  • Marco Matta
  • Marco Re
  • Francesca Silvestri
  • Lorenzo Simone
  • Sergio Spanò
Conference paper
Part of the Lecture Notes in Electrical Engineering book series (LNEE, volume 573)


Digital delays represent one of the crucial elements in a digital Beam-forming system. If signals involved in the Beamforming are wideband signals, it is not possible to use a phase shifter for the delay generation. In this case, other solutions, like fractional delay filters, are required. This paper compares different fractional delay methods in terms of magnitude response, error phase response, computational costs and hardware complexity, considering as target a FPGA implementation.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Gian Carlo Cardarilli
    • 1
  • Daniele Giardino
    • 1
    Email author
  • Marco Matta
    • 1
  • Marco Re
    • 1
  • Francesca Silvestri
    • 1
  • Lorenzo Simone
    • 2
  • Sergio Spanò
    • 1
  1. 1.University of Rome Tor VergataRomeItaly
  2. 2.Thales Alenia SpaceRomeItaly

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