A combinational partial ambiguity resolution method based on dual-station TDCP for low-cost receivers in urban environments

Abstract In response to the difficulties of achieving full ambiguity resolution (FAR) for real-time kinematic with low-cost receivers in urban environments, early scholars proposed partial ambiguity resolution (PAR) methods. However, a PAR method is challenging to apply in the diverse and complex scenarios typical of urban environments. In addition, the frequent occurrence of multipath effects and non-line-of-sight signals significantly increases the difficulty of ambiguity resolution. In response to these challenges, this study presents a quality control and PAR strategy based on the dual-station time-differenced carrier phase (TDCP), and combines this strategy with PAR strategies based on the elevation angle, signal-to-noise ratio (SNR) and decorrelated variance, to enhance the positioning accuracy of low-cost receivers in urban environments. This article refers to it as a combinational PAR (CPAR). Two kinematic experiments are conducted in different urban environments with different boards to evaluate the effectiveness of the proposed strategies. The results show that the PAR strategy based on dual-station TDCP improved the positioning accuracy by 25%–50% compared with that of FAR in dynamic environments, with fixing rate increase of over 40%. The proposed CPAR method performed best in urban environments, achieving centimeter-level positioning accuracy across different scenarios, with a fixing rate exceeding 85%.