Multilateration-based photoacoustic tomography for reconstruction-free 3D particle localization

Localization-based photoacoustic tomography (PAT) has been widely used for resolving the spatial distribution of absorptive targets. However, most existing implementations rely on high-density transducer arrays and reconstruction algorithms that require substantial computational resources, which restrict their accessibility and scalability. We present a multilateration-based photoacoustic tomography (MPAT) that enables precise 3D localization of photoacoustic sources using only a small number of ultrasonic transducers without the need for image reconstruction. Simulations and experiments indicate that MPAT provides 3D multilateration with micrometer-level precision using a small number of transducers and accurately captures both static distributions and dynamic particle trajectories. This study introduces the MPAT method and establishes a theoretical and experimental framework for its systematic evaluation, providing a basis for reconstruction-free and geometry-flexible particle multilateration using sparse transducer measurements.