GNSS卫星精密定轨综述:现状、挑战与机遇

GNSS卫星精密轨道是高精度GNSS应用的基础与前提,GNSS卫星精密定轨技术也一直都是卫星导航领域的研究重点与热点。本文首先介绍了GNSS星座与跟踪数据概况,梳理了精密定轨函数模型、动力学模型及随机模型构建过程中的关键问题,归纳了低轨星载观测和星间链路观测等多源数据增强GNSS精密定轨的研究进展;然后,从应用的角度总结了当前GNSS精密轨道产品的基本状态,并进行了精度评估;最后,讨论了GNSS精密定轨在大网快速解算、多层次观测数据融合、太阳光压模型精化及高精度实时定轨等方面所面临的挑战,并展望了低轨星座、光钟、激光链路等新技术给GNSS精密定轨带来的机遇。

Review of GNSS precise orbit determination: status,challenges, and opportunities

Precise orbit of GNSS satellites is the foundation and prerequisite of GNSS high-precision applications, and the technology of GNSS precise orbit determination (POD) has always been the research focus and hotspot in the field of satellite navigation. This paper firstly introduces the general situation of GNSS constellation and tracking data. The key issues in the construction of the function model, dynamic model and stochastic model in GNSS POD are sorted out. The research progress of GNSS precise orbit determination with the augmentation of low earth orbit (LEO) onboard data and inter satellite link (ISL) data is concluded. Then, from the application point of view, the basic status of current GNSS precision orbit products is summarized, followed by the orbit accuracy evaluation. Finally, the challenges of GNSS precise orbit determination in the rapid solution of massive GNSS network, the data fusion of multi-level observations, the refinement of solar radiation pressure (SRP) models, and the high-precision real-time POD are discussed. The opportunities brought by the development of LEO constellation, optical clock, and laser link in GNSS POD are also prospected.