Testing the quality of information on tracked vessels in a VTS centre withGNSS

This paper describes selective tests performed in the areas of Gdansk and G dynia VTS Centres. The main goal of the tests was to determine the accuracy of position, speed and course estimations measured by shore-based radar VT S tracking systems by using measurements of the same parameters available o n board a tracked vessel equipped with GPS and GLONASS receivers. Six DGPS/ GPS/GLONASS receivers were installed on board a survey vessel, and all of t hem recorded the vessel's route simultaneously with two different VTS radar s - one at Gdansk and one at Gdynia (20 km apart). All DGPS receivers track ed the same reference station. Presented results show that the radar inform ation can be used by VTS operators to provide navigation assistance within certain limits, but these limits must be understood. A more detailed descri ption of the experiment was presented during the IALA Conference in Hamburg in June 1998.