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：成像声纳在水下环境中能够产生清晰的图像，且不受水体浊度和光照条件的影响。新一代二维前视声纳体积紧凑，能够生成高分辨率图像，从而促进水下机器人研究。考虑到在水下环境中进行实验的困难与成本，大量工作集中在声纳图像仿真上。然而，声纳伪影如多路径反射并未得到充分讨论，而这些在水箱环境中不可忽视。本文聚焦于平坦地面回波的影响，提出了一种在声学图像中物理仿真地面回波效应的方法。我们采用单次反弹框架对多次反弹情况进行建模，以提高计算效率。通过对比水箱中采集的真实图像与合成图像，验证了所提出方法的有效性。