Xu, ShaohengLai, Wei-TingZhang, YileZhang, JihuiBastine, AmySamarasinghe, Prasanga N.Abhayapala, Thushara D.2026-06-252026-06-25979-8-3315-7206-8Bibtex:11249221ORCID:/0000-0002-5589-4203/work/218383561ORCID:/0000-0003-4942-7526/work/218387714https://hdl.handle.net/1885/733811975This paper presents a gradient-based algorithm for tracking multiple sound sources in three-dimensional (3-D) space under reverberant conditions. The proposed method, called 3-D Gradient-based Multiple-source Tracking (3D-GMT), operates directly in the continuous spatial domain and estimates source trajectories via a frequency-constrained loss function. Unlike conventional grid-based approaches that suffer from quantization errors and require post-processing filters, 3D-GMT jointly refines all source locations in parallel, implicitly smoothing trajectories and reducing cumulative error. Simulation experiments in reverberant environments demonstrate the robustness and accuracy of 3D-GMT under two representative motion scenarios: straightline paths and complex spiral trajectories. The results indicate potential for applying the method to sound source tracking in reverberant environments with smooth, moderate-speed motion.6enThree-dimensional displaysSmoothing methodsFiltersAccuracySpiralsTrackingPosition measurementRobustnessTrajectorySpeech processing2025-11-2810.1109/APSIPAASC65261.2025.11249221105030501610