A Device for Computing Correlation Functions

Abstract

An analogue device has been constructed for computing autocorrelation functions. On reproducing a function recorded on two channels of a magnetic tape, the spacing of two pick-ups can be varied to obtain the function, delayed in one relative to that in the other. An electrodynamometer wattmeter indicates the average product of the two functions for any value of delay, determining the autocorrelation function. Cross-correlation of two difference functions can also be calculated. Autocorrelation functions and their transforms, the power spectra, are obtained for several types of functions. A comparison of this method of obtaining power spectra with that using an ordinary Fourier analysis indicates that the latter is preferable for the particular conditions outlined.

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Document Details

Document Type
Technical Report
Publication Date
Jun 16, 1950
Accession Number
AD1214406

Entities

People

  • A. E. Hastings
  • J. E. Meade

Organizations

  • United States Naval Research Laboratory

Tags

Communities of Interest

  • Energy and Power Technologies
  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Abstracts
  • Amplitude
  • Amplitude Modulation
  • Analyzers
  • Autocorrelation
  • Bandwidth
  • Carrier Frequencies
  • Cross Correlation
  • Electronics
  • Fourier Analysis
  • Frequency
  • Frequency Bands
  • Magnetic Tape
  • Mechanical Waves
  • Military Research
  • Periodic Functions
  • Power Spectra
  • Spectra
  • Square Waves
  • Wave Analyzers
  • Waves

Readers

  • Electrical Engineering
  • Image Processing and Computer Vision.
  • Regression Analysis.

Technology Areas

  • Space