EGNOS improves safety for maritime navigation in China
The fog today is hanging heavy on the Yangtze River making conditions for navigation rather difficult, however one ferry goes forward with no special worries. The captain is using the highly accurate satellite navigation system, EGNOS.
The European Geostationary Navigation Overlay Service (EGNOS) is an initiative of the European Space Agency (ESA), the European Commission and Eurocontrol.
This boat trip is the first trial testing satellite navigation with EGNOS in China and is the first real joint work between Chinese and European Space Agency engineers on the promising domain of satellite positioning. It represents a new cooperation between China and Europe on the Global Navigation Satellite System.
We are in Wuhan, the heart of China, on the third longest river in the world after the Amazone and the Nile. The Yangtze separates the north and south of the former Empire of the Middle and is a busy maritime highway. It carries important traffic from the coast in Shanghai to the Three Gorges Dam. Wuhan is 1500 km inland from the China Sea and is the fourth largest city in China with a population of more than 7 million and a big port along the Yangtze.
The fog obscures the view of the opposite bank, especially where the Yangtze spans more than one kilometre. Onboard the ferry, near the captain, a computer screen displays a map of the Wuhan river crossing. A small point shows the position of the boat based on measurements made with EGNOS, the European Geostationary Navigation Overlay Service. The system uses GPS signals to provide a more accurate signal with added integrity.
For several months teams in China and Europe have worked closely to prepare tests using the EGNOS signal which is currently in a test bed phase. The EGNOS test bed signal is available above China relayed by a geostationary satellite positioned above the Indian Ocean.
To make these trials possible, a temporary regional ground network of stations had to be implemented. Three Ranging and Integrity Monitoring Stations (RIMS) were installed in China: one in Shanghai, one in Fangshang near Beijing, and one in Wuhan. This enabled a triangle of EGNOS data availability (like GPS) and ionospheric corrections.
Firstly, the Chinese Sismological Bureau conducted static tests last December. A campaign of EGNOS data collection on six different sites showed very good availability and accuracy of the EGNOS performances inside the temporarily installed EGNOS triangle. The accuracy obtained with the EGNOS test bed signal improved the accuracy of GPS by a factor of three.
Dynamic tests were then made by the Dalian Maritime Institute with the support of the Chiangjiang Waterway Institute who provided the boat. These trials allowed a check of the quality and availability of EGNOS in China in the busy built up urban environment of Wuhan. Bridges and buildings can normally cause interferences that can in turn affect the signal. Wuhan was therefore a good test of the reliability of the EGNOS signal which is essential for safety in maritime navigation.
This cooperation illustrates the potential of extending EGNOS beyond Europe. It also prepares the ground for the coming cooperation around Galileo on which the EU and China signed a political agreement last September 2003.
During these trials people also got to know each other. Engineers from both sides found they could work well together. Indeed, in front of the Beijing University there is already a joint office: the China-Europe GNSS Technology Training and Cooperation Centre (CENC) which opened last September after the agreement for China’s participation in Galileo on global navigation satellite system which was signed at the highest political level.
In fact, when realizing the dynamism and potential of China for the 21st century such a cooperation seems obvious. After all, it is in China that the magnetic compass was invented more than 2000 years ago, so now China and Europe can work together for the compass of the 21st century: navigation satellite systems.
EGNOS can be used for boat navigation as well as any type of transport or professional application from guiding blind people to virtual tolling.
The EGNOS signal will be available by the middle of 2004 and paves the way for Galileo, due to be operational in 2008. This civil initiative will complement the sole alternative satellite navigation option: the US Global Positioning System (GPS). Galileo, whose development and validation phase is being co-funded by ESA and the EU, will give Europeans - and indeed the world at large - a precise and secured satellite positioning system.
Dominique Detain | ESA