SIMPLE METHOD OF CALIBRATION OF CONVENTIONAL SODAR ANTENNA SYSTEM

The accurate estimation of sodar antenna parameters, back-scattering c ross-section and a knowledge of acoustic absorption in the atmospheric air are needed in case structure parameters are to be computed. In th e paper a simple method using a theoretical antenna directivity patter n, together with measurements of transduction characteristics of the a coustic transducer has been suggested. The method has been used for tw o sodars belonging to the Russian Academy (Sodar Latan-I) and the Nati onal Physical Laboratory, New Delhi. The theoretically and experimenta lly determined directivities of the Sodar Transducer Systems have been compared and it has been found that they coincide rather satisfactori ly within the angles at which the paraboloids of sodars are seen from their respective foci, Computed thermal structure parameter values usi ng Sodar Latan-I based on the above approach have been found to be com parable with the values computed from microthermal data collected simu laneously at the same place.