联合守时当前守时技术的研究热点。发达国家及我国在建设高性能独立守时系统的同时，大力发展联合守时技术，整合分布于各地的原子钟资源，从而提升国家整体守时性能。传统联合守时方法是采用卫星双向或共视手段进行远程原子钟比对，通过加权平均、滤波等方法获得联合守时系统综合时间尺度。但是从实际效果来看，采用传统方法，联合守时系统的性能并没有显著的提升，而且由于守时数据为事后处理，不能及时发现异常，不利于守时系统的实时应用。本项目提出一种实时联合守时方法，引入IGS实时产品和精密单点定位技术，得到各守时实验室与主节点守时实验室的实时比对结果，设计了基于非线性回归模型的联合时间尺度算法。该方法相比于传统联合守时方法，实时性大幅提升，可及时修正异常结果，新的定权方法能够兼顾不同类型原子钟的优良性能，将大幅提升联合守时系统整体性能，为我国建设军民融合的国家联合守时系统提供新的发展思路。

Joint timekeeping is the focus of current time-keeping technology. Developed countries and China is both in the construction of high-performance independent timekeeping system and developing the joint timekeeping technology vigorously, combining the number of atomic clock so as to enhance the overall performance of the country. The traditional joint timekeeping method gets remote atomic clock comparision by two-way satellite or common view, and obtains the timescale of joint timekeeping system through the weighted average, filtering and other methods. However, the traditional method does not show the good performance for joint timekeeping from the actual result. The reason is that the post-processing of timekeeping data can not find malfunction in time, which is not helpful for the timely application of the timekeeping system. This project presents a real-time joint timekeeping method, introduces IGS real-time products and precision point positioning technology, gets the real-time comparison results from timekeeping lab, determines the weight by atomic clock prediction error. Compared with the traditional method, the real-time performance an be improved and the anomalous results can be corrected in time with the new method. The new method can take advantage of the excellent performance of different types of atomic clocks. The overall performance of the joint timekeeping system is greatly improved, and providing new thoughts for the national joint timekeeping system.