GLONASS is Russia's global satellite navigation system that provides positioning and timing data with global coverage. It was developed by the Soviet Union in the 1970s as an alternative to the American GPS system. The first GLONASS satellites were launched in 1982 and full deployment was achieved in 1995 with 24 operational satellites. However, funding issues caused the system to decline until 2001 when Russia was only able to maintain 8 satellites. Recent upgrades to the GLONASS satellites have extended their lifespans and improved their precision.

1. GLONASS – RUSSIAN GLOBAL NAVIGATION
SATELLITE SYSTEM

2. INTRODUCTION
• GLONASS acronym for "Global Navigation Satellite System", is a space-based satellite
navigation system operated by the Russian Aerospace Defence Forces.
• It provides an alternative to Global Positioning System (GPS) and is the only
alternative navigational system in operation with global coverage and of comparable
precision.
• Development of GLONASS began in the Soviet Union in 1976.
• Glonass (a global navigation satellite system) is being built by Reshetnev Information
Satellite Systems and is based on the US global positioning system (GPS).
• It is currently being operated by the Russian Space Forces on behalf of the Russian
Government

4. DEVELOPMENT
• The Soviet Union recognized the need to develop a new satellite-based radio navigation system in
the 1970s.
• The development of the Glonass satellite system began in 1976 with the aim of achieving global
coverage by 1991.
• About 43 Glonass satellites, as well as five additional test satellites, were successfully launched
from 1982 to 1991.
• The Russian Federation took over the development of Glonass upon dissolution of the Soviet
Union in 1991.
• Glonass achieved full deployment in 1995, with 24 satellites positioned in three different orbital
planes.
• Russia was unable to maintain the system until 2001 due to a financial crisis, which resulted in
only eight spacecraft being operational.

6. COMMUNICATION
• The Glonass system transfers data to a ground control station (GCS)
using a standard precision (SP) signal and modified high precision
(HP) signal.
• Real-time data is transmitted to the GCS using a 15-channel
frequency division multiple access (FDMA) procedure.
• FDMA is a channel access technique which assigns different
frequencies to multiple users for communications.
• Swepos, the Swedish national network of permanent satellite
reference stations, is currently integrating Glonass into its
operations.

7. VARIATIONS
• The Glonass system satellites have three versions, namely Glonass, Glonass-M and Glonass-K.
• The Glonass was initially designed for a lifespan of 14 months but later this was extended up to
two years.
• The Glonass-M is an upgraded model which has a lifespan of seven years.
• It features 12 primary antennas for L-band transmissions and laser corner-cube reflectors for orbit
determination and geodetic research.
• Glonass-K is the latest version with a lifespan of ten to 12 years.
• The Glonass-K satellite completed thermal vacuum (TVAC) tests at the RISS facility in June 2010.
• The satellite is fitted with a precision thermal control system to maintain a temperature of 0.1°C.
• It completed acoustic tests in August 2010.

9. INCEPTION
• The first satellite-based radio navigation system developed in the Soviet Union was Tsiklon,
which had the purpose of providing ballistic missile submarines a method for accurate
positioning.
• 31 Tsiklon satellites were launched between 1967 and 1978.
• The main problem with the system was that, although highly accurate for stationary or slow-
moving ships, it required several hours of observation by the receiving station to fix a position,
making it unusable for many navigation purposes and for the guidance of the new generation of
ballistic missiles.
• In 1968–1969, a new navigation system, which would support not only the navy, but also the air,
land and space forces, was conceived.
• Formal requirements were completed in 1970; in 1976, the government made a decision to
launch development of the "Unified Space Navigation System GLONASS".

11. DESIGN
• The task of designing GLONASS was given to a group of young specialists at
NPO PM in the city of Krasnoyarsk-26.
• Under the leadership of Vladimir Cheremisin, they developed different
proposals, from which the institute's director Grigory Chernyavsky selected the
final one.
• The work was completed in the late 1970s; the system would consist of 24
satellites operating at an altitude of 20,000 km in medium circular orbit.
• It would be able to promptly fix the receiving station's position based on signals
from 4 satellites, and also reveal the object's speed and direction.
• The satellites would be launched 3 at a time on the heavy-lift Proton rocket.

13. REFERENCES
• http://www.insidegnss.com/auto/popupimage/GLONASS%20SDCM%20architecture.jpg
• http://www.glonass.it/images/glonass_network.jpg
• http://www.svetandroida.cz/media/2014/05/188269259.jpg
• http://www.navipedia.net/images/thumb/5/5d/GLONASS_SpaceSegmentModernization.J
PG/400px-GLONASS_SpaceSegmentModernization.JPG
• http://www.aerospace-technology.com/projects/glonasssatellites/glonasssatellites3.html
• http://en.wikipedia.org/wiki/GLONASS
• http://www.aerospace-technology.com/projects/glonasssatellites/

14. THANK YOU