Angle Sample Variance of Azimuthally Spread Scattering Processes, Using a Two-Element Array
Abstract
Active echo energy received by a two-element array may be comprised of both spatially coherent and spatially spread scattering processes (such as clutter or reverberation) and isotropic noise. Such inputs may be filtered by a correlation receiver from which range, Doppler and angle estimates can be made. In many cases, these estimates display azimuthal support, such that angle estimates of spatially spread scattering processes are stochastically distributed across the array beamwidth, whereas angle estimates of spatially coherent scattering processes tend to be azimuthally compact. A scattering function model is used to relate the geometry and scattering distributions to the angle estimation problem when a two-element array is used as the receiver. The angle estimate statistics are described by probability density functions which depend upon array geometry, scattering distribution, scattering strength and ambient noise. When multiple measurements of angle are available, the sample variance can be useful as a means to characterize the underlying scattering distribution. Probability density functions of angle sample variance as a function of coherent scattered energy, diffuse scattered energy and ambient noise are developed through a multistep statistical transformation and verified with Monte Carlo estimations. Keywords: Scattering function models; Two-element arrays; Acoustic arrays; Acoustic scattering.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1990
- Accession Number
- ADA223572
Entities
People
- D. W. Ricker
- J. R. Johnescu
Organizations
- Pennsylvania State University