Many have heard words like GPS, GLONASS, GALILEO. Most people know that these concepts mean navigation satellite systems (hereinafter - NSS).
The abbreviation GPS refers to the American NSS NAVSTAR. This system was developed for military purposes, but was also used for solving civilian tasks - determining the location for air, land, and sea users.
In the Soviet Union, the development of its own NSS GLONASS was hidden behind a veil of secrecy. After the collapse of the USSR, work in this direction was not carried out for a long time, therefore NAVSTAR became the only global system that was used to determine the location anywhere in the world. But only the United States has access to another purpose of this system - aiming weapons of mass destruction at a target. And one more not unimportant factor - by the decision of the US military department, the "civil" signal from American navigation satellites and passenger aircraft may be turned off, the ships will lose orientation. This monopoly on the control of the satellite system by the United States does not suit many countries, including Russia. Therefore, many countries Russia, India, Japan, European countries, China, began to develop their own positioning NSS. All systems are dual-use systems - they can transmit two types of signals: for civilian objects and increased accuracy for military consumers. The main operating principle of the navigation system is complete autonomy: the system does not receive any signals from users (no request) and has a high degree of noise immunity and reliability.
The creation and operation of any NSS is a very complex and expensive process, which, due to its military nature, should belong only to the state of the developing country, since it is a strategic type of weapon. In the event of an armed conflict, satellite navigation technology can be used not only for targeting weapons, but also for landing cargo, supporting the movement of military units, carrying out sabotage and reconnaissance operations, which will give a significant advantage to a country that has its own satellite positioning technology.
The Russian GLONASS system uses the same positioning principle as the American system. In October 1982, the first GLONASS satellite entered Earth's orbit, but the system was put into operation only in 1993. The satellites of the Russian system continuously transmit standard accuracy (ST) signals in the 1.6 GHz range and high accuracy (HT) signals in the 1.2 GHz range. Reception of the ST signal is available to any user of the system and provides determination of horizontal and vertical coordinates, velocity vector, and time. For example, to accurately indicate coordinates and time, it is necessary to receive and process information from at least four GLONASS satellites. The entire GLONASS system consists of twenty-four satellites in circular orbits at an altitude of about 19,100 km. The circulation period of each of them is 11 hours and 15 minutes. All satellites are located in three orbital planes - each with 8 vehicles. The configuration of their placement provides a global navigation field coverage not only of the earth's surface, but also near-earth space. The GLONASS system includes a Control Center and a network of measurement and control stations located throughout Russia. Each consumer receiving a navigation signal from GLOGASS satellites must have a navigation receiver and processing equipment that allows him to calculate his own coordinates, time and speed.
Currently, the GLONASS system does not provide 100% access to its services for users, but assumes the presence of three satellites on the visible horizon of Russia, which, according to experts, makes it possible for users to calculate their location. Now the satellites "GLONASS-M" are in orbit of the Earth, but after 2015 it is planned to replace them with devices of a new generation - "GLONASS-K". The new satellite will have improved performance (the warranty period has been extended, a third frequency will appear for civilian consumers, etc.), the device will be twice as light - 850 kg instead of 1415 kg. Also, to maintain the operability of the entire system, only one group launch of GLONASS-K per year will be required, which will significantly reduce overall costs. To implement the GLONASS system and ensure its financing, the equipment of this navigation system is installed on all vehicles put into operation: airplanes, ships, ground transport, etc. Another main purpose of the GLONASS system is to ensure the national security of the country. However, according to experts, the future of the Russian navigation system is not cloudless.
The Galileo system is being created with the aim of providing European consumers with an independent navigation system - independent, first of all, from the United States. The financial source of this program is about 10 billion euros per year and is financed by one third from the budget, and two thirds from private companies. The Galileo system includes 30 satellites and ground segments. Initially, China, along with other 28 states, joined the GALILEO program. Russia was negotiating the interaction of the Russian navigation system with the European GALILEO. In addition to European countries, Argentina, Malaysia, Australia, Japan and Mexico have joined the GALILEO program. It is planned that GALILEO will transmit ten types of signals to provide the following types of services: positioning with an accuracy of 1 to 9 meters, providing information to rescue services of all types of transport, providing services to government services, ambulance, firefighters, police, military specialists and services, ensuring the life of the population. Another important detail is that the GALILEO program will create about 150 thousand jobs.
In 2006, India also decided to create its own navigation system, IRNSS. The program budget is about 15 billion rupees. Seven satellites are planned to be put into geosynchronous orbits. The state-owned company ISRO is working on the deployment of the Indian system. All system hardware will be developed by Indian companies only.
China, wishing to take a leading position on the geopolitical map of the world, has developed its own satellite navigation system, Beidou. In September 2012, two satellites included in this system were successfully launched from the Sichan cosmodrome. They joined the list of 15 spacecraft launched by Chinese specialists into low-earth orbit as part of the creation of a full-fledged satellite navigation system.
The implementation of the program began by Chinese developers back in 2000 with the launch of two satellites. Already in 2011, there were 11 satellites in orbit, and the system entered the stage of experimental operation.
Deployment of its own navigation satellite system will allow China not to depend on the world's largest American (GPS) and Russian (GLONASS) systems. This will increase the efficiency of Chinese economic sectors, especially those related to telecommunications.
It is planned that by 2020 about 35 satellites will be used in the Chinese NSS, and then the Beidou system will be able to control the entire globe. The Chinese NSS provides the following types of services: location determination with an accuracy of 10 m, speed up to 0.2 m / s and time up to 50 ns. A special circle of users will have access to more accurate measurement parameters. China is ready to interact with other countries to develop and operate satellite navigation. The Chinese Beidou system is fully compatible with European Galileo, Russian GLONASS and American GPS.
"Beidou" is effectively used in the preparation of weather forecasts, natural disaster prevention, in the field of transport by land, air and sea, as well as geological exploration.
China plans to constantly improve its satellite navigation system. The increase in the number of satellites will expand the coverage area of the entire Asia-Pacific region.
