MARGAL Prototype Demonstration - Port Applications Pre-Trials Prior to the public demonstration, a series of pre-trials were conducted to provide a means of recording dynamic data about the coast of the United Kingdom and Ireland. Figure 1 identifies the locations of the two pre-trials. Figure 1: Map of the United Kingdom and Ireland, highlighting the locations of the two pre trials. The yellow dot is for the first pre-trial held at Penzance, while the green dot identifies the location of the second pre-trial in Cork. Dynamic data was collected for a period of several days at each site and is used to establish whether the service performance requirements are met through the use of GPS alone, augmented GPS and dual frequency GPS (simulating Galileo). Data recorded from the pre-trials was analysed both in terms of accuracy and continuity. From the recorded data, typical accuracy scatter plots are shown below for each of the data-types recorded. Figure 2: Scatter plot showing error from true position for Dual Frequency GPS Error less than 3.4m (95%) Figure 3: Scatter plot showing error from truth for GPS with augmentation from EGNOS. Error less than 1.03m (95%) Figure 4: Scatter plot showing the error from truth for GPS with radiobeacon augmentation. Error less than 1.26m (95%) Figure 5: Scatter plot showing the error from the truth for autonomous GPS. Error less than 8.9m (95%) For each of the receiver types, the error not exceeded 95% of the time was calculated and is shown in table 1. Table 1: Comparison of GNSS operating modes and the calculated error not exceeded 95% of the time.