Study of the Wind Characteristics of the Atmospheric Turbulence using a Multibeam Sodar

We present the results of acoustic sounding of the atmosphere in summer of 2001. The experiments were carried out using a multibeam bistatic sodar with two parabolic antennas of 15 m in diameter. The distance between the antennas was about 425 m. The transmitting acoustic antenna having 8^° beam width was pointed to the zenith. The four-beam operation of the receiving paraboloid was implemented by mounting four separate microphones in its focal plane. The width of each beam of the receiving antenna was 2.5^°. The beams of the transmitting and receiving antennas crossed at a height about 500 m. The sounding frequency was equal to 576 Hz. The acoustic-pulse duration and repetition period were 2 s and 8 s, respectively. A new procedure for experimental-data processing on the basis of analysis of temporary variations in the Doppler frequency shift of a scattered signal is proposed and approved. The approach based on using structural functions is applied. The preliminary results of analysis of one observation session are presented.