Effective vertical aperture for three‐dimensional arrays in shallow waters

In shallow waters, the effective vertical aperture of an array composed of horizontal and vertical segments may be greater than the water column depth. The extended vertical aperture leads to better decomposition of bottom‐interacting normal modes and hence better range‐depth localization compared with the performance of the vertical subarray alone. The conditions under which the effective vertical aperture gives improved localization performance over a vertical array spanning the water column are demonstrated. The effect of source frequency, ratio of horizontal to vertical array length, and bottom properties on localization performance are discussed.