Array shape reconstruction for a nominally linear array

We consider a thin flexible line array of equispaced hydrophones that is towed through the sea and develop a procedure that estimates the shape of the array. We first define a test that decides if an array is straight or not. The test is applied to the whole array. If it is declared out of shape, the same test is used on parts of it to determine the maximum length of admissible sub-arrays on which the standard processing can be pursued. By combining then the bearings estimated by the different sub-arrays we reconstruct a piecewise linear estimate of the shape of the array. The approach allows to handle quite important deformations with no need for a cooperating source