Estimation of the Two-Dimensional Spectrum of the Space-Time Noise Field for a Sparse Line Array.

Abstract

For a line array immersed in a stationary homogeneous noise field composed of plane waves of differing speeds and angles of arrival, standard beamforming is not useful for estimating the noise spectrum directionality. However, the two-dimensional spectrum of the received noise field enables resolution in temporal-frequency and in spatial-frequency and can thereby indicate the temporal-frequency content and the apparent speed along the line array of plane wave arrivals. The interrelationships and attributes of the space-time correlation, the cross-spectrum, and the two-dimensional spectrum are presented and interpreted via simple examples. A program for estimation of the two-dimensional spectrum for a sparse line array and examples of its use and interpretation are given. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 22, 1973
Accession Number
AD0767641

Entities

People

  • Albert H. Nuttall
  • Ernest M. Montavon
  • G. Clifford Carter

Organizations

  • Naval Underwater Systems Center

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Doppler Effect
  • Frequency
  • Frequency Shift
  • Plane Waves
  • Spectra
  • Standards
  • Stationary
  • Two Dimensional
  • Waves

Fields of Study

  • Engineering

Readers

  • Acoustical Oceanography.
  • Image Processing and Computer Vision.
  • Spectroscopy.

Technology Areas

  • Space
  • Space - Space Objects