GLONASS is a high-technology defense industry product, and an outstanding example of how technologies initially developed for military applications can be adopted for the civilian sector.
Rapid growth in civilian applications of American GPS satellite navigation technology warranted a shift to dual-use (both military and civilian) approach for GLONASS, and a major increase in financing for further development of the system. At the present time, GLONASS orbital constellation is complete. GPS and GLONASS systems have become strategic global means of ensuring national security and economic development. Comparable systems are being developed by European countries (Galileo) and China (Compass).
Maintaining GLONASS system, improving its operational performance and quality of navigation services, and ensuring use of GLONASS along with GPS in Russia and worldwide are as important and wide-ranging as national hydrocarbon exports and electronic society projects, and are continuously monitored by the President and the Government of the Russian Federation.
The first step, aimed at acceleration of development and use of the system was adoption of the Federal Target Program “Global navigation system” for 2002 – 2012. Within five years, successive fulfillment of the Program objectives made use of the Russian navigation system possible worldwide. RF Presidential Decree from 17 May 2007 granted the international community unrestricted access to GLONASS navigation services free of charge. Implementation of the Federal Target Program “Maintenance, development, and use of the GLONASS System”, aimed at enhancing the quality of navigation services for civilian users, is planned for 2012 – 2020.
In August 2008, RF Government Resolution “On equipping transport vehicles, equipment, and systems with GLONASS or GLONASS/GPS satellite navigation devices” was adopted. One of the goals behind the adoption of this document is enhancing the effectiveness of managing traffic flows, safety of passenger transportation and transportation of hazardous and restricted cargoes.
On 14 February 2009, RF Federal Law “On navigation activities” came into effect. This law declares the GLONASS System to be the property of the Russian Federation, and financing for maintenance and development of the System to be the Government’s responsibility. The law mandates use of the Russian navigation system GLONASS by Government executive bodes, regional and local governments, and for transportation of passengers, restricted and hazardous cargos, as well as for carrying out surveying and cadastral work.
In 2010, a set of Government resolutions was adopted, approving safety regulations for various types of transportation vehicles and providing for mandatory installation of GLONASS or GLONASS/GPS satellite navigation equipment. In particular, safety regulations were adopted for wheeled transportation vehicles, railroad rolling stock, high-speed rail, sea and inland waterway transport.
Russian Government signed a number of cooperation agreements on development and use of Russian global navigation satellite system GLONASS with Cabinet of Ministers of Ukraine, Governments of India, Kazakhstan, and other countries.
Primary purpose of the system
Global navigation satellite system GLONASS is intended for determining location (coordinates), speed (velocity vector components), and exact time by various categories of users (maritime, airborne, terrestrial, and other).
The system provides continuous year-round navigation support globally, at all hours and regardless of the weather conditions, to a guaranteed number of mobile and stationary users simultaneously and without interruption throughout the Earth’s surface and at elevations of up to 2,000 km, without limitations.
Unrestricted access to GLONASS civilian navigation signals is freely provided for domestic and foreign users alike.
GLONASS system consists of three elements:
- GLONASS satellite constellation
- Control and management subsystem
- GLONASS user navigation equipment
GLONASS satellite constellation consists of 24 space vehicles, evenly distributed in three orbital planes. Satellites operate in circular orbits at altitudes of 19,100 km. This configuration permits uninterrupted global coverage of the Earth’s surface and terrestrial space by the navigation field.
Glonass-M space vehicles with operational lifetimes of seven years transmit navigation signals in L1 and L2 frequency bands.
Control and management subsystem consist of GLONASS System Control Center and a network of measurement, management, and control stations, distributed throughout the entire Russian territory. Control and management subsystem tasks include control over proper functionality and transmission of control signals to GLONASS space vehicles.
GLONASS user navigation equipment computes its coordinates, speed, and time from received GLONASS satellite navigation signals. Specifications and performance characteristics of navigation equipment for personal use can be confirmed by voluntary certification systems (at manufacturers’ discretion). Equipment used for making measurements is subject to mandatory certification according to Russian laws.
Navigational sighting concept
GLONASS user navigation equipment performs no-request range measurements to four GLONASS satellites, as well as reception and processing of navigation messages. Navigation messages describe satellite position in space and time. By processing obtained measurements and received navigation messages, user’s three-dimensional coordinates and three velocity vector components are obtained, and user’s time scale is linked with Russian National Etalon time scale UTC(SU).
GLONASS development prospects
Maintaining satellite constellation at 24–30 space vehicles (SV), taking into account orbital spares (24 active SV and up to six spare SV, two SV in each orbital plane).
Scheduled replacement of GLONASS-M satellites with the new generation GLONASS-K satellites with a ten-year operational lifetime (flight testing of GLONASS-M SV commenced in 2011).
New generation of satellites feature:
- Additional civilian navigation signals using channel code division on bands L1 and L3
- Increase in accuracy of user navigation fix to three meters or better
- GLONASS system time scale transmission error of 12 ns or better
- Navigational field availability of 98% or better over a 24-hour period
- Compatibility and complementarity with existing GPS and future Galileo and Compass GNSS
- Implementation of search and rescue function as an MEO (medium earth orbit) segment of the Cospas-Sarsat system
Fields of application
Modern satellite navigation solutions are already widely used in various areas of socio-economic sphere, permitting:
- Overland, airborne, maritime, inland waterway, and space vehicle navigation, direction of traffic flows for all modes of transport, control over transportation of valuable and hazardous cargos, control over fishing in territorial waters, search and rescue, and environmental monitoring
- Geodetic surveying and high-precision (within a few centimeters) position fixing for laying oil and gas pipelines, electrical power transmission lines, and in construction
- Synchronization solutions for telecommunications and electric power industries
- Solutions for fundamental geophysical tasks
- Personal navigation for individual users
Satellite navigation is already in use in agriculture, for automated land cultivation by combine harvesters, and in mining industry.
Range of applications for satellite navigation technologies is constantly growing. It is hard to imagine all other new fields, in which applications for satellite navigation systems will emerge next. It is sufficient to note that current real-time absolute positioning accuracy is three centimeters or better.