Abstract:

[Objective] In Real-time Kinematic (RTK) positioning, there is a certain delay when observation data from the reference station propagates to the rover station through a data communication link, along with potential issues such as data interruption and inconsistent data frequencies. [Methods] To solve these problems, asynchronous differential RTK models have garnered significant attention. This study investigates the impact of time asynchrony on the accuracy of differential relative positioning and evaluates the effectiveness of the asynchronous differential RTK model. Based on the fundamental principles and methods, multiple sets of static and dynamic BDS measurements data under varying observation conditions and time delay configurations are used for case validation. [Conclusions] The results indicate that when adopting the asynchronous differential RTK model, compared to synchronous differential processing, both horizontal and vertical accuracies degrade as time delay increases. At a delay of 30 seconds, the positioning accuracy decline remains twice to the synchronous case, while at 60 seconds, positioning accuracies are still maintained within 5-10 cm horizontally and 10-20 cm vertically, which generally meet the requirements of high-precision positioning applications.

Key words: BDS, asynchronous real-time kinematic, time delay, data analysis