GLONASS stands for GLObalnaya NAvigationnaya Sputnikovaya Sistema.

Development of GLONASS began in 1976 by the USSR. Satellites to the system began to be launched since 1982 until 24 of them were launched till 1995. It was designed for military use for navigating ballistic missiles. In 1993, it was officially declared as operational. With the collapse of the Soviet economy, the project got delayed until 2001. Then Russia committed to restoring it.

Now India has partnered into this project. Plans are to execute the operational satellites in orbit with 3 as spares. This system will be on par with US Navstar by 2011.

GLONASS constellation operates at a height of 19,100km with an inclination of 64.8 degrees. Each satellite orbits in approximately 11 hours and 15mins. These orbits are arranged so that 5 satellites are in view to users worldwide.

GLONASS is managed for the Russian government by the Russian Space Forces, and the system is operated by the Coordination Scientific Information Center of the Ministry of Defense of the Russian Federation

Both, Navstar and GLONASS share the same principles in data transmission and positioning methods.

Signals transmitted by satellites are derived from the fundamental frequency of the satellite oscillator. Each satellite transmits on a different frequency using originally a 25-channel FDMA technique spanning from 1602.5625 MHz to 1615.5 MHz, known as the L1 band.

The main difference between GPS and GLONASS is that in GLONASS each satellite has a different frequency, but the same code; whereas in GPS, all satellites use the same frequency but have different codes.

GLONASS uses what is called a frequency division multiple access method (FDMA) whereas GPS and Galileo use a code division multiple access technique (CDMA).