Effect of Finite Radar Pulse Volume on Turbulence Measurements.

Abstract

Equations relating the mean of the Doppler spectrum and the distribution of point velocities, and their spectra are derived under the assumptions that: (1) the scatterers follow the air motion faithfully, (2) the reflectivity is constant, and (3) the beam illumination function is separable. Relationships between the 1-D longitudinal and transverse spectra of the mean velocity and the 3-D spectrum of the point velocities are derived. Numerical computations with a model Kolmogorov-Obukhov turbulence spectrum are performed to illustrate the effects of filtering. The ratio of the total energy under measured spectrum to that under spectrum of point velocities is computed as a function of beam dimensions. An equivalent rectangular filter approximation is proposed for computing the 1-D spectra. Analytical results are obtained for longitudinal spectrum and are shown to be in excellent agreement with numerical results for actual filter.

Document Details

Document Type
Technical Report
Publication Date
Jul 15, 1972
Accession Number
AD0755440

Entities

People

  • David Atlas
  • Ramesh C. Srivastava

Organizations

  • University of Chicago

Tags

DTIC Thesaurus Topics

  • Agreements
  • Computations
  • Cooperation
  • Electrical Engineering
  • Engineering
  • Equations
  • Filters
  • Filtration
  • Illinois
  • Illumination
  • Mathematics
  • Measurement
  • Physical Properties
  • Radar Pulses
  • Spectra
  • Three Dimensional
  • Turbulence

Fields of Study

  • Physics

Readers

  • Approximation Theory.
  • Atmospheric Science / Meteorology, specifically Wind Wave Turbulence.
  • Electromagnetic Wave Scattering and Antenna Radiation Engineering