Depth interference in the deep ocean with application to underwater source localization

In the deep sea, line spectra in target radiated noise often possess a higher signal-to-noise ratio than broadband components. This makes narrowband localization a valuable complement when broadband methods fail. Utilizing a near-bottom vertical array in the deep-sea direct-arrival zone reveals a distinct depth-dependent interference structure. This paper analyzes the variation patterns of two key interference depth intervals with receiver depth, source range, and source depth. Based on this variation pattern, a localization method suitable for narrowband stationary sound sources was proposed, and its effectiveness was verified through simulation and experimental data.