Development of a Sodar for the Study of Planetary Boundary Layer

Abstract

A new sodar system is developed, which has capability of measuring three dimensional wind components in the planetary boundary layer with one parabolic reflector. This is realized by newly designed defocus feed horn arrangements, i.e. three speakers sharing one parabolic reflector make three acoustic beams independently. Wind components are deduced from Doppler frequency shifts with the complex covariance method. Wind data can be obtained up to 400m in height with resolution of 40m and intervals of 2.5 minutes by the present system.