GLOBAL NAVIGATION SATELLITE SYSTEM (GLONASS)

                                                                           GLONASS

 ABSTRACT: Global Navigation Satellite System (GLONASS) is one of the navigational system to show ones own position on the earth any time in any weather, anywhere. This paper addresses this satellite based navigation system at length. The Different generations of GLONASS are discussed. In addition, how this amazing system GLONASS works, is clearly described. GLONASS transmits two signals, this will also clearly discussed in this paper. Finally, the paper ends with advanced application of GLONASS.

INTRODUCTION:  Global Navigation Satellite System, is a radio-based satellite navigation system operated for the Russiangovernment by the Russian Aerospace Defence Forces. It both complements and provides an alternative to the United States' Global Positioning System (GPS) and is the only alternative navigational system in operation with global coverage and of comparable precision.

HISTORY: Development of GLONASS began in the Soviet Union in 1976. Beginning on 12 October 1982, numerous rocket launches added satellites to the system until the "constellation" was completed in 1995. During the 2000s, under Vladimir Putin's presidency, the restoration of the system was made a top government priority and funding was substantially increased. GLONASS is the most expensive program of the Russian Federal Space Agency, consuming a third of its budget in 2010.

By 2010, GLONASS had achieved 100% coverage of Russia's territory and in October 2011, the full orbital constellation of 24 satellites was restored, enabling full global coverage. The GLONASS satellites' designs have undergone several upgrades, with the latest version being GLONASS-K.

The official LOGO of GLONASS is shown below,

 

SYSTEM DESCRIPTION:

     GLONASS is a global satellite navigation system, providing real time position and velocity determination for military and civilian users. The satellites are located in middle circular orbit at 19,100 km altitude with a 64.8 degree inclination and a period of 11 hours and 15 minutes. GLONASS' orbit makes it especially suited for usage in high latitudes (north or south), where getting a GPS signal can be problematic. The constellation operates in three orbital planes, with 8 evenly spaced satellites on each. A fully operational constellation with global coverage consists of 24 satellites, while 18 satellites are necessary for covering the territory of Russia. To get a position fix, the receiver must be in the range of at least four satellites, three of which will be used to determine the user's location and the fourth to synchronize clocks of the receiver and the three other spacecraft.

SIGNALS:  GLONASS satellites transmit two types of signals:

•      A Standard Precision (SP) signal and

•      An obfuscatedHigh Precision (HP) signal.

DEVELOPMENT :

The Development of GLONASS is can divided into three generations.

• The true first generation of satellites is known as URAGON and has 3 – axis stabilized vehicles, generally weighing 1,250 kg.

•  The second generation of satellites , known as GLONASS- M, were developed beginning in1990 and first launched in 2003. These satellites possess a substantially increased lifetime of seven years and weigh slightly more at 1,480 kg.

• The third generation of satellites, known as GLONASS- K . It is the first unpressurised GLONASS satellite with a much reduced mass of 750 kg. It has an operational lifetime of 10 years.

GROUND CONTROL:

         The ground control segment of GLONASS is entirely located within former Soviet Union territory. The Ground Control Center and Time Standards is located in Moscow. 

 

APPLICATIONS:

Ø  GLONASS is used mainly for Navigational Purposes.

Ø  GLONASS receivers are used in several aircraft , Navy ships and many other places.

Ø  The iPhone 4Swas the first Apple product using both GPS and GLONASS navigation.In now-a-days we can see GLONASS in many mobile devices which is used for navigational purposes.

CONCLUSION:

       GLONASS, a satellite based navigation system, thus can be used to determine the position of an object on earth. As discussed above, its application field is vast and new applications will continue to be created as the technology evolves. GLONASS can also interface with other similar projects such as GPS and IRNSS– India's regional navigation system  to account for unpredictable applications. Thus, the GLONASS constellation, like manmade stars in the sky, can be used for guiding and navigation.