This paper describes the development of a new acoustic planar array antenna system to produce beam steering patterns for Doppler sodar applications. The antenna has been integrated with the tweeter elements that enable the beam to be steered in the desired direction. Experiments have been conducted in sodar laboratory to confirm that the beam forming and echo detection functions very well. As a result, it is found that the beam is maintained in the desired direction with a beam width of 10°, and the normalized field pattern of planar array as a function of its position is observed for varying frequencies. The antenna contains distributed transmit (TX) and receive (RX) modules, and generates one fan beam on transmit, and a number of simultaneous pencil beams on receive.