Temporal Feature Extraction in Photorefractive Resonators.

Abstract

A holographic optical system listens to an incoming signal and extracts the most common repetitive temporal features of that signal. An example might be to extract the features of Morse code, which consists of two tone lengths and two pause lengths. This optical system is self-organizing, in that very little a priori information is imbeded in the system to indicate what form the temporal signals take. The primary constraints imposed on the signal is (1) finite bandwidth; (2) limited feature duration and (3) rates of reoccurrence. The optical apparatus uses a photorefractively pumped multimode optical oscillator having a delay line in the feedback loop. The delay line serves to translate the temporal dimension into a spatial one, and it also builds into the system a notion of the direction of time. Temporal feature extraction takes place as a competitive interaction among sets of modes, which are termed chronomodes. Experiments illustrate the principles of such a system by extracting the two most probable temporal features from a signal imposed on a laser beam. (MM)

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1994
Accession Number
ADA292908

Entities

People

  • Dana Z. Anderson
  • Gan Zhou
  • Germano Montemezzani

Organizations

  • University of Colorado Boulder

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Acoustic Signals
  • Computing System Architectures
  • Delay Lines
  • Dimensionality Reduction
  • Electro-Optic Modulators
  • Extraction
  • Feature Extraction
  • Laser Beams
  • Lasers
  • Morse Code
  • Neural Networks
  • Optical Lattices
  • Optomechanics
  • Recognition
  • Resonators
  • Signal Processing
  • Wave Mixing

Fields of Study

  • Physics

Readers

  • Educational Psychology
  • Neural Network Machine Learning.
  • Optical Physics and Photonics.

Technology Areas

  • AI & ML
  • AI & ML - Bayesian Inference
  • Directed Energy