Impact of Rover Pole Holding on the Positioning Accuracy of RTK-GNSS

Abstract

Satellite positioning methods [global navigation satellite system (GNSS) positioning] are used for various applications, which is especially true in the case of the real-time kinematic (RTK) method. This method provides real-time differential data for surveyors to achieve reliable positioning accuracy. In this paper, theoretical foundations for testing the GNSS receivers according to ISO 17123-8 standard are introduced. Using this standard, the positioning performance of a geodetic GNSS receiver Trimble R8s was evaluated using Bosnian Active GNSS Network Bosnia and Herzegovina positioning service (BIHPOS) and a conventional base-rover RTK solution. The main purpose of this study is to evaluate the relationship between the ranging pole support and the quality of the RTK position solution. Besides that, results from RTK positioning using a single base station versus a network of base stations are also compared. Several comprehensive tests were conducted, which involved the most common field procedures where the pole is hand-held by the surveyor and positioned vertically using a circular bubble, whereas in other experiments, a bipod was attached to the range pole, and the GNSS instrument was mounted directly to a tripod via optical plummet-equipped tribrach. The precision, absolute accuracy, and relative accuracy of positioning solutions obtained from these experiments were compared and discussed. The results indicate that regardless of how the RTK range pole was supported, the effect of rover pole holding is within the error of satellite surveys. Furthermore, it was confirmed that using a bipod or a steady hand can produce as accurate RTK results as a tripod.