Implementation of binary sequence windows in linear arrays for underwater sound

The application of binary sequence windows for wide beam generation from equispaced arrays for underwater sound has been studied. The approach enables a simple way of beam enlargement employing a single driving source or a single channel front-end for projectors and receivers respectively. The departure of the experimentally obtained directivity patterns from the equal elemental response model prediction has been studied. The array element cross-coupling was identified as a cause of the discrepancies. The details of the element interaction were investigated using Finite Element Analysis models. Several practical examples of binary sequence windows for receive and transmit beam generation from evenly spaced linear arrays were studied experimentally. The effect of amplitude weights calculated for flatter directivity patterns was assessed.