This article presents a newly invented emergency positioning system deployed on a satellite communication on-the-move (SOTM) platform, which can extend the SOTM communication function to the positioning function. Inherent to the SOTM system's high reliability, this emergency positioning system can effectively estimate the vehicle's position by fusing a geosynchronous orbit (GEO) satellite Doppler frequency observation and inertial navigation system (INS) of a SOTM-mounted moving vehicle when the global navigation satellite system (GNSS) is unavailable. It is a great challenge to use GEO Doppler frequency measurement with weak observability to correct the INS's cumulative error to estimate the position of the vehicle. In this article, the traditional inertial measurement unit (IMU) pre-integration model is improved to meet the needs of large-scale and high-precision navigation. In addition, we use graph optimization (GO) to estimate all states in the trajectory, which can effectively improve the observability of the error and reduce the nonlinear influence. We evaluated the system on a Ku-band SOTM platform, and the experimental results indicate that the system can achieve a convergent positioning accuracy of tens of meters. This method can provide emergency positioning in the case of GNSS interference.

中文翻译：

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融合GEO卫星多普勒观测和INS的SOTM应急定位系统


本文提出了一种新发明的部署在移动卫星通信（SOTM）平台上的应急定位系统，可以将SOTM通信功能扩展到定位功能。凭借SOTM系统固有的高可靠性，当全球导航卫星系统出现故障时，该应急定位系统可以通过融合地球同步轨道（GEO）卫星多普勒频率观测和搭载SOTM的移动车辆惯性导航系统（INS）来有效估计车辆位置(GNSS) 不可用。利用可观测性较弱的GEO多普勒频率测量来修正INS累积误差来估计飞行器位置是一个巨大的挑战。本文对传统惯性测量单元（IMU）预积分模型进行改进，以满足大范围、高精度导航的需求。此外，我们使用图优化（GO）来估计轨迹中的所有状态，可以有效提高误差的可观测性并减少非线性影响。我们在Ku波段SOTM平台上对该系统进行了评估，实验结果表明该系统可以实现数十米的收敛定位精度。该方法可以在GNSS干扰的情况下提供紧急定位。