GPS AND GLONAS

1. Indian Institute Of
Technology, Roorkee
CEN-614 THEORY AND APPLICATIONS OF GIS
ASSIGNMENT NO. 2
THE DIFFERENCE BETWEEN
GPS & GLONASS
M.TECH – INFRASTRUCTURE SYSTEMS
SUBMITED BY – HARSH BAMNIYA
Enrollment – 22554003
GUIDED BY – PROF. S.K.GHOSH

3. What is GPS ?
Global Positioning System (GPS) refers to the NAVSTAR Global Positioning
System, a constellations of satellites developed by the United States
Department of Defence. At first the GPS was made for military use only, but
later made accessible to civilians as well. But recently, GPS is most widely used
GNSS satellite constellation in the world.
What is GLONASS ?
Globalnaya Navigazionnaya Sputnikovaya Sistema (GLONASS) is an acronym which is translated
from Russian, this means Global Navigation Satellite System. It is accessible for both military and
civil use and also provides real time position and velocity determination.

4. Difference 1
The main difference between GPS & GLONASS is that, with GPS satellites use the same radio
frequencies but have different codes for communication while GLONASS satellites have the
same codes but use different frequencies, allowing satellites on the same orbital plane to
communicate.
Difference Between GPS & GLONASS ?
Difference 2
GPS and GLONASS uses different technology
Difference 3
GPS has 32 satellites operating at 6 different orbital planes at an altitude of 20,180 km with an
angle of 55 degree from equator.
GLONASS has 24 Satellites operating at 3 orbital levels at an altitude of 19,100 km with an angle
of 64.8 degree from equator.

5. Difference 4
GPS satellites transmit on 1575.42 MHz(L1 Band - Civilian) and 1227.6 MHz(L2 Band -
Military) and uses CDMA. Every satellite transmits same Frequency with a Unique Code as
identifier for each satellite.
GLONASS satellites transmitts on 1602MHz(L1 Band - Civilian) and 1246 MHz(L2 Band -
Military) and uses FDMA. Every satellite transmits the same code, but at different
frequencies at the vicinity of 1602MHz(L1 Band) and 1246 MHz(L2 Band).
GPS and GLONASS satellites provides Good accuracy and performance in normal test
scenarios. But in case of an urban scenario with more multipath coming to picture, it is
always better to have a system with dual (GPS+GLONASS) mode available for better
accuracy in positioning.
P Code (L2 band) is an encrypted code and can be accessed by authorised personnal only
ie US military in case of GPS and Russian military in case of GLONASS or any other
authorized agencies from this country. This P Code provides very accurate position as
close as 2meters. So for military reasons its needed for each of this country to have their
on satellite system.

7. End