An Evaluation of Adaptive-Beamforming Techniques Applied to Recorded Seismic Data

Abstract

This report presents time-domain maximum likelihood adaptive beamforming results for data from the Alaska Long-Period Array and the Korean Short-Period Array. Adaptive-beamforming detection gain relative to beamsteering is investigated for unmixed long-period seismic events in the presence of background noise and for simulated mixed events where two data samples, each containing a signal, are summed to create a composite sample containing an interfering event. In the adaptive beamforming studies for background noise, the performance of two different adaptive algorithms, the effect of using closely-spaced partial arrays instead of the full ALPA array, and the effect of different frequency filters applied to the input channels before array beamforming are examined. In the interfering-event analysis, the relative on-azimuth to off-azimuth event strength at which an on-azimuth event detection is possible determines the detection gain of adaptive multichannel filtering over time-shift-and-sum beamforming.

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Document Details

Document Type
Technical Report
Publication Date
Dec 31, 1974
Accession Number
ADA011849

Entities

People

  • Leo J. O'brien
  • Thomas E. Barnard

Organizations

  • Texas Instruments

Tags

Communities of Interest

  • Air Platforms
  • Energy and Power Technologies
  • Sensors

DTIC Thesaurus Topics

  • Algorithms
  • Artificial Intelligence
  • Background Noise
  • Beam Forming
  • Beam Steering
  • Computer Programs
  • Detection
  • Filters
  • Filtration
  • Frequency
  • Noise Reduction
  • Probability
  • Schematic Diagrams
  • Signal Processing
  • Simulations
  • Steering
  • Time Domain

Fields of Study

  • Engineering

Readers

  • Computer Programming and Software Development.
  • Phased Array Antenna Design.
  • Team-Based Human-Centered Cognitive Task Decision Making and Information Performance.

Technology Areas

  • Space
  • Space - Space Objects