Imaging sonar produces clear images in underwater environments, independent of water turbidity and lighting conditions. The next generation 2D forward looking sonars are compact in size and able to generate high-resolution images which facilitate underwater robotics research. Considering the difficulties and expenses of implementing experiments in underwater environments, tremendous work has been focused on sonar image simulation. However, sonar artifacts like multi-path reflection were not sufficiently discussed, which cannot be ignored in water tank environments. In this paper, we focus on the influence of echoes from the flat ground. We propose a method to simulate the ground echo effect physically in acoustic images. We model the multi-bounce situations using the single-bounce framework for computation efficiency. We compare the real image captured in the water tank with the synthetic images to validate the proposed methods.

翻译：成像声呐能够在浑浊水体与弱光条件下生成清晰的水下图像，不受水体浊度与光照条件影响。新一代二维前视声呐体积紧凑且可生成高分辨率图像，有力推动了水下机器人技术研究。鉴于水下实验实施的困难性与高成本，大量研究聚焦于声呐图像仿真技术。然而，声呐伪影（如多路径反射效应）在水池环境中不可忽略，相关讨论尚显不足。本文重点研究平坦地面回波对声学成像的影响，提出了一种物理模拟地面回波效应的声学图像生成方法。为提升计算效率，我们采用单次反射框架对多次反射场景进行建模。通过对比水池实测真实图像与合成图像，验证了所提方法的有效性。