WANG Fupo  LI Shuqiu  LI Yu  HUANG Haining

(Institute of Acoustics, Chinese Academy of Science  Beijing  100190)

Received Jan. 16, 2009

Revised Jun. 6, 2009

Abstract It is always an important problem in sonar signal processing for towed array to distinguish the target between port and starboard. It is studied in this paper the normalized beam output function for the parallel twin-line array and found a method that can enhance its port and starboard ambiguity suppression by equalizing the amplitude and phase of the beam output form the conventional beam forming. This method gets the weight value by analyzing the normalized beam output function, and then uses the amplitude weight and phase compensation for beam outputs of the twin arrays to cancel the conjugate (mirror) output. Therefore, the port and starboard restrain ratio is maximized. Both the computer simulation and sea trial data showed that this is a simple and practical method, can better enhance the port and starboard restrain ratio, especially when the band is wide.　　　　 

PACS numbers: 43.30, 43.60