Application of Integrated Satellite DGPS/GPRS Navigation and Hydrographic Systems for Safe Sailing on Great Mazurian Lakes in Poland

摘要

Warmia and Mazury region is frequently called the Land of a Thousand Lakes. It is the center of recreation for tourists from all over Poland and from abroad. There is an amazing opportunity for sailors and fishermen. Almost all of lakes don't have up-to-date digital charts. The most part of them has been measured almost 50 years go. Existing analogue maps don't present the real and accurate bottom surface. Therefore it is very important to ensure the general safety which could be reached by creating digital, bathymetric charts, marking the inland waterways and especially dangerous shallow stone reefs on inland waterways of Great Mazurian Lakes. The team of Chair of Satellite Geodesy and Navigation has developed integrated technology of bathymetry surveying, which makes possible navigation of the small hydrographic boat along the pre-defined profiles, examination of bottom shape, computation of water volume, elaboration of bathymetric charts and monitoring of dangerous shallow places. For the developed Integrated Bathymetric System a number of professional equipment units are used, as follows: the DGPS/RTK receivers, GPRS modems, EA 501 P Simrad single frequency digital echo sounder, SportScan side scan sonar and special GPS/CAD software. The hydrographic equipment is mounted on board of the motorboat. The small but safe and easy to use hydrographic boat, called "ORBITA", is used for raw-data collecion during these integrated measurements. The implemented technology allows designing of measurement profiles, navigation along the profiles, recording positions and bathymetric data, making correlation of these both data and finally creating digital bathymetric maps. The developed Integrated Bathymetric System combined with side scan sonar gives a great chance to study the underwater environment, especially monitoring underwater dangerous stones and shallow areas. The paper presents application of DGPS/GPRS satellite navigation and hydrographic systems to monitoring and safety sailing on Great Mazurian Lakes. The first results of the experiments carried out on the biggest lake in Poland, called Sniardwy Lake, using GPS receivers working in DGPS/GPRS mode will be presented. Differential GPS satellite measurements were based on the GPRS data teletransmission system, originally developed in the Chair of Satellite Geodesy and Navigation, of Olsztyn University (UWM).