Tomographic Mapping of Water Temperature and Current in a Reservoir by Trust-Region Method Based on CAT

Remote sensing of water parameters and flow dynamic progress is of critical importance to water environment observation. Underwater acoustic tomography technology uses multiple sound stations to construct distributed sensing network for large-scale measurement, which has big superiority in water parameter observation compared with fix-point measurement. Water parameter variation progress can be monitored with an underwater acoustic tomography sensing system. This article develops a grid-averaged trust-region method for water parameter detailed profiling with coastal acoustic tomography (CAT) systems. A remote sensing experiment was conducted with five CAT systems from February 28 to March 7, 2022, in the Huangcai Reservoir in Changsha, China. Four CAT systems were deployed in the same position with different depths of sound transceivers, and another CAT station was set 650 m apart. Water temperature and flow current reconstruction results along the sound propagate Section were analyzed with the trust-region method and compared with the temperature data acquired with the temperature sensor. The accuracy and feasibility of this method are verified with observation results.