Conditional indirect correction solution with dual GNSS RTK receivers in vehicle positioning and navigation using global satellite navigation technology

Abstract

Global Navigation Satellite Systems (GNSS) technology is widely used in various civilian and military applications. However, for some applications requiring high-precision positioning and real-time navigation, such as construction machinery, deep-sea vessel navigation, or uncrewed aerial vehicles for surveying and mapping tasks, GNSS technology still faces limitations due to various factors affecting accuracy in terms of horizontal positioning and unstable altitude at a certain level as required. To address this issue, we propose a solution involving dual-frequency GNSS receivers with differential corrections to enhance the accuracy of positioning points. In this method, each navigation device is equipped with 2 GNSS receivers with antennas placed at a fixed distance apart. The central processing unit simultaneously collects data from 2 receivers and data from the reference station to perform real-time kinematic (RTK) processing. The spatial baseline measurements between the receivers and the reference station and between the receivers themselves form a spatial triangle. The known distance between the antennas allows for establishing a constraint condition. Indirect error minimization based on the least squares principle is then applied to improve the position accuracy while controlling measurement errors, widespread errors encountered in GNSS RTK. Experimental results demonstrate that the proposed solution can significantly improve accuracy compared to conventional GNSS RTK solutions and maintain stability below 3 cm.