Accession Number:

AD0876995

Title:

Signal Processing by Fiber Optical Modeling of an Acoustic Array,

Descriptive Note:

Corporate Author:

NAVAL UNDERWATER SYSTEMS CENTER NEW LONDON CT NEW LONDON LAB

Report Date:

1970-09-28

Pagination or Media Count:

29.0

Abstract:

The concept of optical modeling of acoustic arrays for the purpose of performing Fourier transform signal processing is developed. An optical model is an array of light-emitting elements, usually similar in geometry to an acoustic array, that facilitates reconstruction of a sound field with coherent light. Dielectric waveguides, glass fibers that transmit light signals preserving phase and amplitude, are essential elements in a two-stage processor for a planar array. This processor performs frequency analyses on all hydrophone channels and then, sequentially as a function of frequency, it performs two-dimensional space transforms. In the processor for the planar array, the dielectric waveguide fibers rearrange light signals representing frequency-analyzed hydrophone signals into an optical model of the array. Modeling of certain three-dimensional arrays also may be possible with fibers. A 10-element line array of dielectric waveguides has been constructed to show that a significant number of fibers can be controlled in relative phase. Control of both phase and amplitude in a dielectric waveguide fiber also has been demonstrated. This report suggest the potential inherent in optical Fourier methods that are being developed to provide a basis for the design and construction of new processors for sonar. Author

Subject Categories:

  • Computer Hardware
  • Acoustic Detection and Detectors
  • Fiber Optics and Integrated Optics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE