## 4 Discussion  
The purpose of this study was to assess the positional accuracy, availability, integrity, and service continuity of a commercially available PNT solution that uses DGNSS-SBAS multiple GNSS channels during a simulated dry-land slalom and real-world on-water slalom. The main findings indicate that the PNT solution achieved accurate trajectory distances in a non-ecological environment, as they were within 1.5% of a known distance. The coefficient of variance was less than 0.5%, suggesting consistent and reliable results. The dilution of precision measurements demonstrated ideal-excellent levels of position accuracy, while the horizontal root-mean-square was within 0.3 m, indicating precise horizontal positioning. Furthermore, when considering real-world validity, the study revealed improved results for the dilution of precision data due to an increase in the number of satellites used, presenting no differences for positional accuracy, availability, and the integrity of the PNT solution. In order to assess method validity, a dry-land simulation typical of slalom canoeing was performed [22], where residual analysis of all data points was visually inspected within ArcGis Pro via a georeferenced aerial image overlay, as per Figures 1A and 2B. The visual data inspection of each trial identified no data set errors for positioning in relation to the known trajectories used (Figure 2B), showing exceptional continuity of the PNT solution. The high number of satellites used (-18) in the dry-land simulation supports previous work that relates the increased number of satellites in view, and used by the receiver, to increase the geometric dilution of precision [27]. The subsequent dilution of precision measures (Figure 3) supports the PNT solutions' ability to use high quality satellite constellation and geometry in the horizontal plane where HDOP was ideal (<1), and reflects low levels of atmospheric or multipath interference, and/or receiver noise [8; 26; 28]. This is further supported by a 3D perspective through the PDOP values, which are slightly higher and suggest further research needs to investigate altitude changes from a slalom perspective on  
Figure 6: Dependent variable comparisons between test mean data for each trial for (**A**) number of satellites used by device, (**B**) the Hrms (m), (**C**) the horizontal dilution of precision (HDOP), and (**D**) the 3D position dilution of precision (PDOP). a whitewater course where a gradient, while small, is present. In this data set, where no elevation changes occurred, the primary focus was on horizontal accuracy. The reported Hrms (0.23 \(\pm\) 0.02 m), while not as good as that reported in skiing [25], still provides a reasonable level of certainty around the geographical positioning of athletes during the slalom simulation. This is reflected by the high overall accuracy, with a deviation of less than 1.5% when compared to the actual distance. Additionally, the precision was equally high, with a CV of less than 0.5% observed over 50 trials. It is likely that the distance of the base station mount (41 km) from the receiver could influence the accuracy. However, pilot work with this PNT solution found that the distance used in this study still provided useful data. If more accuracy is desired due to no base station being nearby, then using a device with a mobile RTK (real time kinematic) function would be preferable. Future research needs to explore the relationship between the base station distance from a slalom venue and PNT accuracy requirements for slalom in this regard. Within slalom, performance is determined to a certain extent by line choice or trajectory, which is influenced by cognitive planning and/or reactions to external stimuli in the moment [2,3]. Therefore, it is crucial not only to assess the ability of PNT solutions to accurately log geographical positions but also to differentiate between the various trajectories taken.