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Constant Directivity Beamforming

  • Darren B. Ward
  • Rodney A. Kennedy
  • Robert C. Williamson
Part of the Digital Signal Processing book series (DIGSIGNAL)

Abstract

Beamforming, or spatial filtering, is one of the simplest methods for discriminating between different signals based on the physical location of the sources. Because speech is a very wideband signal, covering some four octaves, traditional narrowband beamforming techniques are inappropriate for hands-free speech acquisition. One class of broadband beamformers, called constant directivity beam-formers, aim to produce a constant spatial response over a broad frequency range. In this chapter we review such beamformers, and discuss implementation issues related to their use in microphone arrays.

Keywords

Spatial Response Microphone Array Array Geometry Constant Directivity Spatial Aliasing 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • Darren B. Ward
    • 1
  • Rodney A. Kennedy
    • 2
  • Robert C. Williamson
    • 2
  1. 1.Technology and MedicineImperial College of ScienceLondonUK
  2. 2.The Australian National UniversityCanberraAustralia

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