Performance analysis of passive acoustic localization using asynchronous hydrophone arrays in shallow-water environment

This study proposes and evaluates a passive sonar localization method utilizing asynchronously distributed horizontal and vertical hydrophone arrays in a shallow-water environment. The proposed method integrates spectral alignment techniques using warped frequency spectra from horizontal hydrophone arrays and multipath-based striation frequency analysis from vertical arrays. Through simulations under varying acoustic velocity profiles, seabed characteristics, and signal-to-noise ratios (SNR), the combined method demonstrated improved localization accuracy and robustness compared to each individual approach. This asynchronous, sensor-cooperation-free approach is expected to enhance the performance and reliability of passive acoustic monitoring systems operating in complex shallow-water conditions. This work was supported by the Korea Research Institute for Defense Technology Planning and Advancement (KRIT) Grant funded by Defense Acquisition Program Administration (DAPA) (Integrated Underwater Surveillance Research Center for Adapting Future Technologies, 2023–2029) under Grant KRIT-CT-23-026.