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  • Research Article
  • Open Access

Analog VLSI Models of Range-Tuned Neurons in the Bat Echolocation System

EURASIP Journal on Advances in Signal Processing20032003:598240

  • Received: 3 May 2002
  • Published:


Bat echolocation is a fascinating topic of research for both neuroscientists and engineers, due to the complex and extremely time-constrained nature of the problem and its potential for application to engineered systems. In the bat's brainstem and midbrain exist neural circuits that are sensitive to the specific difference in time between the outgoing sonar vocalization and the returning echo. While some of the details of the neural mechanisms are known to be species-specific, a basic model of reafference-triggered, postinhibitory rebound timing is reasonably well supported by available data. We have designed low-power, analog VLSI circuits to mimic this mechanism and have demonstrated range-dependent outputs for use in a real-time sonar system. These circuits are being used to implement range-dependent vocalization amplitude, vocalization rate, and closest target isolation.


  • neuromorphic engineering
  • echolocation
  • bat
  • biosonar
  • delay tuning

Authors’ Affiliations

Neurosciences and Cognitive Sciences Program, University of Maryland, College Park, MD 20742, USA
Department of Electrical and Computer Engineering, University of Maryland, College Park, MD 20742, USA
Institute for Systems Research, University of Maryland, College Park, MD 20742, USA


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