SOME THEORETICAL ASPECTS OF THE SONAR GRAPHIC INDICATOR
Abstract
This report deals with some of the more important theoretical aspects of one of the Navy's newest sonar devices, the Sonar Graphic Indicator. Emphasis in Part I is upon the visual patterns which are produced by the device in response to a periodic signal, and to the important tactical uses to which these patterns may be put. Parts II and III concern the device's ability to perform in the presence of reverberations and random noise. Its action in discriminating against reverberations is studied in Part II by considering in detail the patterns which are produced by a superposition of two sinusoids of slightly different frequency. In Part III is considered the problem of choosing the device's design parameters in such a manner that the operator can best detect a periodic signal in the presence of random noise. Information regarding the optimum values of the bias, bandwidth, and nominal operating frequency is deduced on the basis of plausible, but admittedly assumed, notions about the observer's psychology with respect to visual perception. Particular attention is paid to noise spectrums which are "white," or which fall at 6 db per octave.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1953
- Accession Number
- AD0030443
Entities
People
- H. M. Trent
- R. E. Roberson
- S. P. Thompson
Organizations
- United States Naval Research Laboratory