1. Introduction to the Galileo Plan
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On March 26, 2001, the Minister of Transport of the 15 member states of the European Union decided to start the Galileo satellite navigation and positioning system plan in Brussels. On the 27th, European Commission President Prodi praised this decision as a breakthrough. He believed that Galileo’s plan will be successful and took a solid step forward in breaking the world’s dominance of the world’s satellite navigation and positioning system and creating a new phase of the EU’s space industry. .
The Galileo plan is expected to cost between 3.2 billion and 3.6 billion euros, consisting of 30 high-orbiting satellites, distributed on three orbital planes with an orbital altitude of 24,000 km and an inclination of 56 degrees. The infrastructure consists of two parts, space and foundation. The satellite will provide users with accurate time and error global positioning services of no more than one meter, and compete with the United States' Global Positioning System (GPS) and Russia's Global Positioning System (GLONASS) for the market.
The Galileo plan is gradually implemented in four phases. The first phase is the system feasibility assessment or definition phase (before 2000); the second phase is the development and testing phase (2001-2005); the third phase is the deployment phase (2006-2007); The stage is the commercial operation phase (after 2008).
Why is the EU so focused on developing its own satellite navigation and positioning system? First of all, satellite navigation and positioning can be applied to all aspects of people's lives. Galileo plans to create huge economic and social benefits, break the US monopoly in this respect, and win a considerable market share for the EU. The authorities expect that Galileo plans to create 150,000 high-tech jobs for the EU, with an annual economic return of 10 billion euros. The EU estimates that the sale of only aeronautical and marine terminal equipment will cost €15 billion between 2008 and 2020. Second, the EU's development of this project can serve the European Common Security Defense Policy that the EU is now strongly advocating. In recent years, the EU has always advocated having its own security system independent of NATO. The Galileo program provides the necessary technical support for the implementation of the European Common Security Defence Policy. Third, the EU believes that the 21st century is a century of rapid development of science and technology. The EU must occupy an important position in the future world. It is indispensable to occupy the world's high-tech positions. Without a technological leadership, the EU has no dominant position in many future affairs.
As Prodi said, the Galileo plan is a technological revolution for the European Union, and it will bring pride to people no less than the "Airbus" aircraft and the "Ariane" rocket. Of course, the EU has encountered many difficulties in developing the space industry, both technically and pressured from foreign countries such as the United States. However, the EU is well aware that this is a major event concerning the future of Europe. It is a monopoly and anti-monopoly struggle. It is a diplomatic struggle involving political, economic, military and national interests. Therefore, it is pursuing the establishment of its own independent satellite navigation and positioning. The determination on the system has never wavered.
2. Application of GALILEO satellite positioning technology in marine engineering
The launch of the Galileo plan will undoubtedly have a major impact on the world. For China, this technology will have an epoch-making impact on China's national economic construction. The EU's development of the Galileo plan mainly breaks the monopoly of the United States from the perspective of commerce and politics. For China, since key technologies are monopolized by foreign companies, we mainly consider it from the perspective of application. Here, we discuss them in the ocean.
Marine engineering applications mainly include Coastal Works and Offshore Support. The former is mainly used within 40km, making it easy to build its own base stations, including dredging, infrastructure and maintenance (terminals, ports, etc.) and land. Reconstruction, beach farming, coastal zone management, etc.; offshore support is mainly used in offshore (about 500 km offshore), and generally requires the establishment of wide-area differential systems, including oil and gas, pipeline laying, communication cables, and optical cables. In addition, relevant ocean surveys, such as mineral resources, ocean environmental surveys, etc.
2.1. Coastal Engineering
Coastal engineering activities take place near the shore, including the construction and maintenance of ports and waterways, land rehabilitation, coastal protection and riverbank protection. The development and utilization of coastal resources are planned in accordance with national or local government development plans.
As far as location services are concerned, coastal engineering project executives generally use GPS as the positioning device and a small part to use the total station for positioning. Coastal engineering is a high value-added component that has been widely used in positioning technology and attracting a large number of high-end new technologies for many years to ensure the best productivity of the project. This project has taken place in almost every country on five continents.
In the coastal engineering market, the value associated with the positioning system is very limited compared to the total expenditure of the project. However, the vast majority of coastal engineering production productivity depends on the performance of the positioning equipment. Therefore, the choice of positioning system solution is not only subject to technical factors, but also the influence of economic factors on it.
In the coastal engineering market segment, it has always been through the purchase of equipment and rarely through the rental location service to obtain the benefits of positioning technology. Since the 1980s, the former positioning technology based on terrestrial radio transmission has been replaced by the growing differential GPS. In recent years, in order to obtain accurate positioning applications, there is a large development trend in Real Time Kinematic (RTK) technology.
Therefore, coastal engineering will likely take advantage of the GALILEO satellite positioning technology offering, which is truly economical and technical, replacing existing GPS-based solutions.
2.1.1. Current status of coastal engineering in China
In China, most of the coastal projects are managed by the government or directly implemented. Within 40km of the coast, most of the coastal projects are oil development, such as Shengli Oilfield, Liaohe Oilfield, Laizhou Bay Oilfield, Beibu Gulf Natural Gas Development, etc., as well as offshore power plant construction, such as Fujian Nuclear Power Plant, Shandong Haiyang Nuclear Power Plant, etc. Including coastal zone investigation and utilization, inland sea improvement projects, port and dock infrastructure construction and maintenance, waterway dredging, fish farming and so on.
For the positioning system used, more than 95% use DGPS, and the differential data mainly uses the coast beacon set established by the Ministry of Communications. This system is a Local Area Differential GPS with an accuracy of 5m or less. The coordinate system is the WGS84 coordinate system. For high-precision users, the centimeter-level RTK positioning technology has been used by more and more departments, especially in the channel dredging, which can greatly improve work efficiency and save costs.
In addition, coastal projects are not only considering coastal engineering projects such as waterway or hydrographic surveys, embankment construction, land rehabilitation, beach eutrophication, etc., and even artificial island construction is part of normal channel dredging activities. Each type of work requires a range of professional support tools: suction or propeller dredgers, lateral unloading vessels, barges, and pontoon docks that can be loaded and unloaded with cranes. For all of these applications, high-quality, high-efficiency work is a major requirement for coastal engineering, and at the same time it must be considered for cost.
Commercial costs have prompted the channel dredging industry to use state-of-the-art positioning technology in order to maximize the return on investment. Due to the practicality of radiolocation equipment in the coastal engineering market, a large number of terrestrial beacon-based positioning devices are widely used. Especially in recent years, RTK GPS has been widely used due to its excellent performance in fast dynamic measurement schemes. At the same time, RTK GPS is steadily improving in accuracy. For example, in the precision-demanding dredging project, using the centimeter-level accuracy provided by the real-time dynamic positioning technology, real-time water level change observation and tidal level correction can be performed in the process of filling earth and stone, and the project can be completed with high precision in a short time. These applications can be fully implemented with dual-band satellite positioning receivers and amazing RTK/LRK performance.
2.1.2. Coastal Engineering Applications
Since the beginning of the 21st century, the Chinese government has increased capital investment in marine development. Therefore, the construction of many infrastructures has brought the coastal engineering market to a prosperous scene, such as the land reconstruction project for the construction of the new airport, and the port. The channel is dredged, the rivers for river shipping are deepened, the bridges between the islands are built, the land island project, the inland sea remediation, the new coastal zone survey, and so on. This means that coastal engineering has a large investment in positioning equipment and may still have a large growth in the future.
2.1.3. Current and upcoming new technologies
n Wide-area differential technique
Wide-area differential technology has further improved GPS positioning accuracy and expanded its scope. Now it is mainly operated by: Fugro's StarFix, Racal (Thales)'s SkyFix, NavCom, C&C and United States JPL laboratory's StarFire ( RTG) and other wide-area differential systems, combined with Internet technology, use dual-frequency GPS to effectively eliminate errors such as ionosphere, atmosphere, orbit, and clock. The horizontal positioning accuracy is improved to decimeter level, vertical accuracy is 70cm, and differential data is passed through maritime communication. Satellite broadcasts, covering the globe, in addition to the two poles. The virtual RTK technology introduced by Trimble has further expanded the scope of RTK technology while maintaining a high-precision positioning of centimeter level.
n Precision positioning technology
The development trend of ocean engineering is to develop precision engineering, and high-precision positioning plays a major role. High-precision positioning technology is mainly RTK, LRTK (Racal), virtual RTK technology. Precision engineering in coastal engineering has surpassed common coastal engineering.
n “Galileo+GPS†hybrid positioning system
In the field of surveying applications, no one doubts the joint use of GPS and Galileo, and the positioning equipment hardware manufacturer will soon produce a "Galileo+GPS" receiver. Although Russia's Global Orbiting Navigation Satellite System (GLONASS) is not operating well, the "GPS+GLONASS" receiver is now widely used in measurement and scientific research. There are at least two main advantages to this combination: first, more visible satellites are available (twice as much as one of the satellite positioning systems alone); second, because GPS and GLONASS are two separate systems, there are Better reliability and integrity. There is a huge impact here that this may be the case (or in part) in the selection of coastal engineering location equipment, ie using a hybrid "Galileo+GPS" receiver instead of using Galileo alone or using a GPS receiver alone.
In order to reduce this trend of simultaneous use of GPS and Galileo systems and accelerate the market share of GALILEO satellite positioning systems, Racal recommended in its research report that GALILEO plans to jointly adopt some of the results of GPS positioning systems (the same WGS84 geocentric coordinates) System and same transmission frequency).
2.2. Offshore engineering
Offshore engineering usually takes place offshore the ocean and is often closely related to the offshore oil and gas industry. In addition to the application of seismic exploration, the application of offshore engineering to the ocean is mainly related to the oil and gas industry. As the offshore engineering support technology, the positioning technology mainly includes: well field measurement, floating product storage, floating production storage offloading (FPSO) positioning, drilling platform positioning/anchor vessel positioning/water building construction, supply vessel, Pipe laying, Remotely Operated Vehicles (ROV), etc.
The offshore support segment is a global market with operations all over the world. It is controlled by many private merchants who are driven by the economic benefits of offshore support. In the offshore support part, most of the location services are done by service providers. They not only provide positioning devices or other instruments with differential correction, but they also provide professionals to complete all the configuration requirements of the project. Therefore, depending on the service provider's different service objects, the instruments they use can be used from this project to another project.
In the offshore support market, the cost of the positioning system accounts for only a small percentage of the cost of the entire project; however, the reliability and productivity of the project depend largely on the performance of the positioning equipment. Bad. Therefore, as long as there is an advanced technology that can produce high production efficiency, the price of instruments and equipment should not limit the generation and development of new technologies.
The offshore support market has benefited from positioning technology for a long time in the past by investing in equipment and rental positioning equipment. Since the 1980s, SYLEDIS technology based on the application of terrestrial radio transmission or other terrestrial radio transmission technology has been replaced by the existing DGPS technology, which is now a major positioning technology. However, offshore support applications focus on the integrity of positioning through the use of different Quality Assessment (QA)/Quality Control (QC)-oriented procedures. For example, it would require the use of another parallel alternative system, such as an additional DGPS system, or a terrestrial radio transmission system, or even consider the GLONASS system to address location integrity issues.
Therefore, offshore support will undoubtedly utilize the GALILEO system as long as the available and available GALILEO features are obtained, which are specifications based on the true choice of GPS solutions.
2.2.1. Status of offshore engineering in China
In China, in terms of offshore support, especially away from beacon stations and difficult to set up base stations, the location data of specialized positioning service companies are generally rented for positioning. For example, Fugro has many restrictions in its use, such as Marine engineering involved in commercialization can only be used for research and general marine survey projects, and the scope of the survey is limited and only standard positioning services are provided. Now, some companies, such as C&C, can provide precise positioning services. In China, especially in offshore oil, the positioning services are almost exclusively operated by foreign companies, such as Racal and Fugro, for precision marine engineering measurement and drilling platform movement, positioning, pipeline laying, etc., in the South China Sea, East China Sea, and Bohai Sea. This is especially true for oil and gas development projects.
The characteristics of offshore support applications are the diversity of short-term work. Therefore, many projects in our country are to rent positioning equipment to rental companies or location service providers, but these positioning equipments exhibit receiver performance that is more suitable for long-term operation. Any one of them is continuously used in different engineering projects.
2.2.2. Offshore engineering support application
The general level of offshore support is now mainly for some offshore support applications (more than 95% of all offshore support work). In the general application of offshore support, there are mainly: the typical 1 to 3 meter accuracy level, by obeying RAIM (established and recommended by UKOOA), emphasizing the quality evaluation and quality control aspects for project safety implementation.
There is now a steady growth trend in which most project needs are done using RTK precision grade technology, such as in high-precision offshore engineering surveys, precise positioning of rigs and FPSO projects.
In the precision requirements of offshore support precision level, the positional accuracy of the point can be reduced to better than 0.1m. According to the positioning technology, the lower level of positioning information integrity and reliability is also acceptable. However, due to the development of RTK precision positioning technology, this situation will be improved, and the same data integrity and reliability guarantees as the general level of offshore support can be obtained through RTK technology.
In offshore engineering, the development and exploitation of offshore oil and natural gas requires specialized vessels, barges, product storage and handling equipment (FPSO), and rig movement. Therefore, obtaining a reliable and accurate position is a prerequisite for ensuring the efficiency and feasibility of the implementation of these projects. In the face of these urgent needs, offshore support positioning is often based on simultaneous and redundant 2 to 3 different positioning systems; in special cases, differential GPS, laser tracking system and ultra-short baseline acoustic positioning system are combined to form a dynamic positioning system for joint operation. In addition, more and more growth demand has turned to deep waters—1000 meters deep or deeper. In this environment, how to apply differential GPS to determine the position of underwater positioning vessels is the key technology.
Most remote control devices and offshore engineering support work, subsea surveys, pipeline laying or rig mobile applications generally require only meter-level accuracy. However, in addition to considering accuracy, operators should pay special attention to the simultaneous application of quality control procedures by using different positioning systems or positioning devices in parallel.
However, in offshore engineering, the requirement for leveling is required to increase daily, whether it is to meet space control, or to perform tilting and settlement observation of water buildings, or even to move more important drilling platforms. ? The gradual development of precision leveling technology will fully support solutions to these application areas, ensuring reliable RTK data in the most difficult environments.
There is no doubt that offshore work needs to meet the needs of the present and the future, while using GALILEO and GPS positioning systems will be the inevitable development of technology.
2.2.3. Galileo plan and offshore engineering in China
The realization of the Galileo plan has more choices for positioning technology in China's offshore engineering. However, according to the development of satellite positioning technology, differential positioning technology, especially wide-area differential technology, has been applied by more and more departments. We should be committed to building a wide-area differential system based on satellite positioning systems in China to meet the needs of China's national economic construction.
The emergence of the Galileo system has broken the monopoly market of the US GPS. For the application-oriented offshore engineering positioning market in China, the project execution cost will be reduced a lot. This is a good thing, but we should pay attention to foreign marine exploration. The company, after China's accession to the WTO, entered the Chinese market in a big way, undoubtedly increased the competitors of domestic engineering companies. We must use the Galileo plan to seize the opportunity to fully utilize our technology and work on the wide-area differential system. Construction and technology research, relying on domestic advantages, has enabled our own marine exploration companies to grow and occupy the domestic market.
3. Suggestions and conclusions
China is a large maritime country with a large population and a large land area. The development of marine resources is one of the key development directions of China's economic construction in the future. As a key technology for marine development, satellite positioning technology must be taken seriously. It is not only the ocean aspect, but also the positioning application in other fields. In terms of technology development and system construction, it must be incorporated into the government's behavior. Focusing on the future, we need to develop Own satellite navigation system, the good news is that the Chinese government has approved the development of the Big Dipper navigation system, which means that we will have our own satellite navigation and positioning system in the future.
In the current satellite positioning system, the GPS system is the most widely used, and the GLONASS system has few stars in use. However, as a civilian, we can only use the GPS standard positioning service, and its fine code positioning service is only an American ally. Provided that the GPS third-generation system will replace the existing GPS satellite positioning system in the years before and after 2030, the L3 band will be added to the third-generation system, and the A/C code will be added to the L2 band for higher reliability. The new system will add more visible satellites (30 to 36 satellites), but the US government has never promised that GPS will always be available to civilians, which means that the US government can turn off the signal whenever it wants. The emergence of the Galileo system will undoubtedly break the monopoly of the United States. The Galileo plan focuses on civilian use. Of course, considering the military interests of the EU, Galileo plans to consider three different positioning services. One is the free standard positioning service, similar to the GPS A/C. Code; second is the high-precision positioning service for charging; third is military positioning, but some EU member states insist that the Galileo system is purely for civilian use. In any case, the emergence of the Galileo system will have a major impact on China's national economic construction.
In the face of a variety of satellite positioning systems, as users, we must make corresponding strategies to truly make satellite positioning technology serve China's national economic construction. Whether it is offshore engineering, land surveying and other areas, we suggest that the government should consider the following:
n Regardless of the type of satellite positioning system used, in order to obtain sophisticated positioning services, other techniques must be used to eliminate the error. Especially for real-time location services, using differential technology to obtain high-precision positioning, we need to develop our own positioning technology. In addition, in order to reduce unnecessary duplication of investment, it is recommended that China develop its own wide-area differential positioning system, which should basically meet the ocean in China. Land location needs.
n Due to the existence of users with different positioning accuracy, the government should consider whether the investment in the positioning service system construction planned by us after the emergence of the Galileo system is feasible and feasible. Will the system become a waste product after the construction? Especially with the development of land transportation, logistics, geographic information systems, and intelligent transportation, all localities are competing to develop GPS-based service systems, and there are multiple GPS service systems in the same city. This duplication of construction is not only a waste now. And once the Galileo system is opened, some systems will become waste. Therefore, the government must develop a corresponding positioning service system development plan based on long-term interests.
In short, the emergence of the Galileo system has provided us with new technical support means for us to develop and utilize the ocean. Our relevant scientific research institutions must seize the opportunity to further develop China's satellite positioning application technology and meet the needs of China's national economic construction.
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