Accession Number : AD0755440

Title :   Effect of Finite Radar Pulse Volume on Turbulence Measurements.

Descriptive Note : Technical rept. Aug 71-Jul 72,

Corporate Author : CHICAGO UNIV ILL LAB FOR ATMOSPHERIC PROBING

Personal Author(s) : Srivastava,Ramesh C. ; Atlas,David

Report Date : 15 JUL 1972

Pagination or Media Count : 36

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.

Descriptors :   (*ATMOSPHERIC SOUNDING, METEOROLOGICAL RADAR), (*ATMOSPHERIC MOTION, RADAR REFLECTIONS), DOPPLER EFFECT, POWER SPECTRA, SPECTRUM ANALYZERS, DOPPLER RADAR

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE