Array Beampattern Using Goal

The desire beampattern of a sound source at the far field can be synthesised by controlling the relative amplitudes and phas es of each array element. However, when one or more elements in the array fail, the bearnpattern at the far field is severely distorted. The Goal Attain optimisation algorithm is used to adjust the relative gains of th eremaining array elements so as to generate an optimised pattern closely resembles the original beampattern. The quality of each optimised pattern is evaluated and compared based on a defined performance index. The effectiveness of the Goal method is tested in both the Uniform Planar and Linear Array sonar systems.