Signal Processing by Fiber Optical Modeling of an Acoustic Array,
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)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 28, 1970
- Accession Number
- AD0876995
Entities
People
- Elias Snitzer
- Eugene L. Green
- Luther W. Smith
Organizations
- Naval Underwater Systems Center