Passive range-only target motion analysis using array-invariant processing and an extended Kalman filter in shallow-water acoustic waveguides

Abstract

In passive sonar systems, target motion analysis (TMA) traditionally relies on bearing-angle measurements from horizontal line arrays, a technique commonly referred to as bearing-only target motion analysis (BOTMA). This paper presents an alternative TMA approach that incorporates range measurements obtained from two vertical line arrays (VLAs), here termed array invariant-based range-only target motion analysis (AI-ROTMA). The proposed method employs an extended Kalman filter to enhance target tracking accuracy, integrating source-receiver ranges derived from the array invariant method with the two-point localization results. The performance of AI-ROTMA was evaluated using ship-radiated noise data from R/V Onnuri, collected using two VLAs during the Shallow Water Acoustic Variability Experiment (SAVEX-15). Compared with the two-point localization method that uses only range measurements, AI-ROTMA provided significantly more reliable estimates of both range and velocity. These results highlight the potential of integrating array-invariant techniques into passive sonar TMA for enhanced tracking performance in realistic ocean environments.