Noise Robust Speech Watermarking with Bit Synchronisation for the Aeronautical Radio

  • Konrad Hofbauer
  • Horst Hering
Part of the Lecture Notes in Computer Science book series (LNCS, volume 4567)


Analogue amplitude modulation radios are used for air/ ground voice communication between aircraft pilots and controllers. The identification of the aircraft, so far always transmitted verbally, could be embedded as a watermark in the speech signal and thereby prevent safety-critical misunderstandings. The first part of this paper presents an overview on this watermarking application. The second part proposes a speech watermarking algorithm that embeds data in the linear prediction residual of unvoiced narrowband speech at a rate of up to 2 kbit/s. A bit synchroniser is developed which enables the transmission over analogue channels and which reaches the optimal limit within one to two percentage points in terms of raw bit error rate. Simulations show the robustness of the method for the AWGN channel.


Speech Signal Linear Prediction Watermark Embedder Additive White Gaussian Noise Channel Very High Frequency 
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 2007

Authors and Affiliations

  • Konrad Hofbauer
    • 1
    • 2
  • Horst Hering
    • 2
  1. 1.Graz University of Technology, Austria, Signal Processing and Speech Communication LaboratoryAustria
  2. 2.Eurocontrol Experimental CentreFrance

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