Currently we use mostly American Global positioning system (GPS) to get access the exact location. But someday or other we have to be dependent upon our own country made navigational system because India has no control over GPS. Suppose in some unforeseen situation (like war, disaster, enmity) if GPS is not accessible, then all processes or people relying on GPS would be crippled. Then just think about the scenario? How people will get location, how ships will sail, how aircraft will navigate and land?
In the time of war, US have the authority to suspend GPS services. In such situation, it would be almost impossible for the defense armies to track their enemies.
Or just imagine about a situation of wartime, when GPS will not provide the accurate data for some reasons, then it will be almost impossible for Indian missiles to hit the actual target. In fact, during Kargil war, the US has suspended GPS for both India as well as Pakistan. So it’s very imperative to make our own navigational system.
World other countries are also developing their own navigational system. For example, Russia has developed GLOSNASS; China as developed Beidou and European Union has developed GALELIO.
Difference between GPS and IRNSS
GPS is owned & controlled by the the US. It has 24 orbiting satellites and a global network of ground stations. So, it covers the every part of the world.
Other hand, IRNSS (Indian Regional Navigation Satellite System) is a regional system. It will have only 7 Satellite and try to cover India and a range of 1,500 km beyond its borders. As in the case of GPS, IRNSS will provide a more accurate data for users.
Four satellites of IRNSS – IRNSS-1A, IRNSS-1B, IRNSS-1C and IRNSS-1D – have been already launched while IRNSS 1E will be launched in January 2016, and IRNSS 1F and 1G, both in March 2016.
Architecture of IRNSS
The INRSS will consist of three segments-space, ground and user.
The space segment consists of a constellation of seven satellites: three (Geostationary Orbit) GEOs located at 34° E, 83° E and 131.5° E and four (Gyosynchronous Orbit) GSOs at an inclination angle of 29° placed two each at with equator crossing at 55° and 111° East.
IRNSS ground segment consists ground stations transmit the data to Navigation Control Centres. A total of 20 stations are planned, most of them located at airports. IRNSS will have two types of signals in L5 (1176.45 MHz) & S (2492.028 MHz) band.
IRNSS will provide two basic services-
a-Standard Positioning Service (SPS) for common civilian users.
b-Restricted Service (RS) for special authorized users like defense and military.