The range limitation on radar-acoustic sounding systems (RASS) due to atmospheric refractive turbulence

The effects of acoustic refractivity fluctuations on the operation of a radar-acoustic sounding system (RASS) have been calculated. Using the Born approximation, the electromagnetic field scattered from a spherical acoustic pulse whose sphericity is perturbed by transmission through the turbulent medium between the source and scattering volume was determined. The resultant system gain reduction factor changes the dependence on range
R
of the total received power from an
R^{-2}
dependence for a homogeneous atmosphere to
R^{-18/5}
in strong turbulence. This new range dependence can occur at distances of the order of a few hundred meters for sufficiently strong turbulence.