Ultrashort baseline (USBL) systems play a crucial role in underwater navigation and localization. However, the positioning accuracy is susceptible to acoustic outliers and time-varying delays. To ensure the accuracy of measurements, acoustic results from the previous cycle are transmitted to the host computer at the beginning of the subsequent cycle. Localization errors induced by time-varying delays accumulate with the increasing acoustic period. To address these challenges, modified state and measurement equations are derived, compensating quickly and accurately for delays. Besides, a robust filter algorithm is proposed for time-varying non-Gaussian noise. The simulations demonstrate that the proposed algorithm can effectively suppress time-varying delays, and horizontal errors do not increase with the acoustic period. The horizontal positioning accuracy is improved by at least 68% compared to the other algorithms. Furthermore, the algorithm also shows excellent performance in the trial test and a 20% improvement in three-axis positioning errors. The proposed algorithm offers the advantage of improved localization accuracy and robustness, which makes it a valuable solution for addressing acoustic outliers and time-varying delays in USBL-based underwater navigation systems.

中文翻译：

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具有时变延迟的基于混合分布的鲁棒SINS/USBL集成导航

超短基线（USBL）系统在水下导航和定位中发挥着至关重要的作用。然而，定位精度容易受到声学异常值和时变延迟的影响。为了确保测量的准确性，前一个周期的声学结果会在下一个周期开始时传输到主机。由时变延迟引起的定位误差随着声学周期的增加而累积。为了应对这些挑战，导出了修改后的状态和测量方程，从而快速、准确地补偿延迟。此外，针对时变非高斯噪声提出了鲁棒滤波算法。仿真结果表明，该算法能够有效抑制时变延迟，并且水平误差不会随着声波周期的增加而增加。水平定位精度较其他算法提高至少68%。此外，该算法在试用测试中也表现出了优异的性能，三轴定位误差改善了20%。所提出的算法具有提高定位精度和鲁棒性的优点，这使其成为解决基于 USBL 的水下导航系统中的声学异常值和时变延迟的有价值的解决方案。