Analysis of Short-Period Seismic Signals and Noise Recorded at LASA and TFO

Abstract

Short-period beams were formed for twenty-four events recorded at both the LASA and TFO arrays. The mean RMS noise in the frequency range 0.4-3.0 Hz for the LASA beams was 0.16 millimicron, and for the TFO beams 0.13 millimicron. Noise reduction by beam formation in the range 0.4-3.0 Hz varied from 17 to 23 db for LASA, from 12 to 18 db for the 37-sensor TFO array, and from 6 to 14 db for the 19-sensor TFO subarray. Averaging over several source regions in the distance range 25 degrees <delta<90 degrees, the signal-to-noise ratio for LASA was about one db better than that of TFO for common events. The improvement in signal-to-noise ratio for LASA beams was found to increase 4 db by changing the number of sensors employed in the beams from 48 to 340 while keeping the minimum sensor spacing delta = or > 1km.

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Document Details

Document Type
Technical Report
Publication Date
Sep 21, 1971
Accession Number
AD0739181

Entities

People

  • Herman J. Mecklenburg
  • Robert P. Masse

Organizations

  • Teledyne Technologies

Tags

Communities of Interest

  • Sensors

DTIC Thesaurus Topics

  • Amplitude
  • Arrays
  • Beam Forming
  • Beam Steering
  • Contracts
  • Detection
  • Detectors
  • Earthquakes
  • Efficiency
  • Epicenters
  • Frequency
  • Noise
  • Noise Reduction
  • Seismic Arrays
  • Travel Time
  • Virginia

Fields of Study

  • Physics

Readers

  • Electronics Engineering
  • Seismology
  • Sensor Fusion and Tracking Systems.

Technology Areas

  • Space
  • Space - Space Objects