Accession Number:

ADA199756

Title:

Research on the Statistics of Grain Lattice Echoes and Their Use in Grain Size Estimation and Grain Echo Suppression

Descriptive Note:

Annual rept. 1 Jun 1984-29 Sep 1985

Corporate Author:

DREXEL UNIV PHILADELPHIA PA DEPT OF ELECTRICAL AND COMPUTER ENGINEERING

Report Date:

1985-12-15

Pagination or Media Count:

161.0

Abstract:

Two topics dealing with the reflection of ultrasound bursts from random media are discussed in this work. Chapter 2 develops a general formulation of the echo received from a random scatterer ensemble illuminated by a short electromagnetic or sonic signal. A gradient in either scatterer concentration or in the field function of the transmitterreceiver will return an echo which is partially spatially coherent i.e. specular. Furthermore from the degree of coherency the scatterer concentration and scattering cross-section can be calculated. Signal processing techniques are given for the reduction of clutter noise created by random media composed of a high concentration of point scatterers. The problem is to enhance a target embedded in a random medium when the clutter noise variance and the target echo location and amplitude are unknown. The minimization algorithm splits the received signal spectrum into n frequency windows. The minimum of the squared signals at each range delay

Subject Categories:

  • Acoustics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE