Seismic Streamer Position and Shape Estimation

Optimal utilization of the acoustic signals received by the individual hydrophones of a towed seismic streamer requires knowledge of the relative cross-track positions of the hydrophones and their absolute positions with respect to the towship. Consequently, it is necessary to estimate the streamer shape so that the hydrophone positions can be estimated. A polynomial approximation is considered, and justification is given for its use as a basis function. Maximum likelihood techniques are used to develop optimal estimates (in the mean square sense) of the horizontal and vertical polynomial coefficients. Because these estimates are efficient, absolute error variance expressions are calculated. An example is provided to demonstrate the potential of the optimal shape and position estimator.