Assessment of antenna array-aided RTK positioning with different cut-off elevation angles

To evaluate the positioning performance of antenna array-aided real time kinematic (RTK), the mathematical model of antenna array-aided RTK is compared with the mathematical model of RTK firstly, and then a set of static measurement is processed with antenna array-aided RTK and RTK at different cut-off elevation angles. It is demonstrated that the strength of RTK is enhanced by increasing the redundancy of the double-difference observation equation from antenna array, which can improve the success rate of ambiguity resolution and positioning accuracy. Based on the combination of GPS and BDS, the antenna array-aided RTK achieves 93.6% ambiguity resolution success rate at a large cut-off elevation angle of 50°. Moreover, the horizontal accuracy of the fixed solution is better than 1 cm and the height accuracy is better than 2 cm, which can fulfill the demand of high-precision positioning and improve the applicability of RTK in urban canyon environment.