The layout of seafloor datum points is the key to constructing the seafloor geodetic datum network, and a reliable underwater positioning model is the prerequisite for achieving precise deployment of the datum points. The traditional average sound speed positioning model is generally adopted in underwater positioning due to its simple and efficient algorithm, but it is sensitive to incident angle related errors, which lead to unreliable positioning results. Based on the relationship between incident angle and sound speed, the sound speed function model considering the incident angle has been established. Results show that the accuracy of positioning is easily affected by errors related to the incident angle; the new average sound speed correction model based on the incident angle proposed in this paper is used to significantly improve the underwater positioning accuracy.

中文翻译：

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基于平均声速的水下定位新模型

海底基准点布局是构建海底大地基准网的关键，可靠的水下定位模型是实现基准点精确部署的前提。传统的平均声速定位模型由于算法简单高效，在水下定位中普遍采用，但对入射角相关误差敏感，导致定位结果不可靠。基于入射角与声速的关系，建立了考虑入射角的声速函数模型。结果表明，定位精度容易受到入射角相关误差的影响；