Depth Estimation for Line Spectrum Sources with a Vertical Line Array in Deep Water

Source depth estimation in the direct arrival zone of deep water can be achieved by matching the multipath arrival angles, arrival time delays, or interference cycles in the frequency domain. A vertical array with a high spatial spectrum resolution or a source with a sufficient bandwidth is generally required for these methods. This paper proposes a depth estimation method for line spectrum sources, though matching the measured interference structure in the arrival angle domain obtained from the beamforming of a vertical line array, with the modeled interference structure under different assumed source depths. The effectiveness of this method is verified by a towed source data collected by a bottom-moored vertical linear array in the South China Sea.