Development and Evaluation of an Experimental Parametric Acoustic Receiving Array (PARRAY)
Abstract
The development, test, and evaluation of an experimental parametric acoustic receiving array (PARRAY) with a pump-hydrophone separation of 340 m are described in this report. Tests in Lake Travis, Texas, demonstrated a greater than 40 dB reduction in the self-noise floor of the experimental PARRAY compared to any previous parametric acoustic receiver. This reduction in the self-noise floor was achieved through state-of-the-art advances in four major hardware subsystems employed in the experimental PARRAY: high spectral purity pump signal generation; commensurate power amplification; high efficiency, high power transducer element and array design; and detection of sideband signals with very small modulation indices. Design and test results are presented for a crystal controlled oscillator with spectrum level single sideband phase noise less than -170 dB referenced to the carrier level. The design of a band elimination receiver preprocessor capable of detecting sideband signals approaching 180 dB below the carrier is presented and discussed. Test results are presented for simple, high efficiency transducer elements and arrays. Tests and experiments that were performed to evaluate the experimental 340 m PARRAY are described.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 16, 1979
- Accession Number
- ADA072307
Entities
People
- C. Richard Reeves
- David F. Rohde
- M. Ward Widener
- Robert A. Lamb
- Tommy G. Goldsberry
Organizations
- University of Texas at Austin