ISRO successfuly launches PSLV-C32 carrying IRNSS-1F

What is IRNSS?
Indian Regional Navigation Spacecraft System (IRNSS) is the Indian navigation system which envisages establishment of regional navigation system using a combination of GEO and GSO spacecraft.
Significance of IRNSS:
It entails primarily the strategic significance as it is glaringly evident that no country can afford to depend on a foreign country’s constellations for navigation during war scenarios. IRNSS will make Indian Armed Forces self-reliant. While advanced nations like US and Russia are having GPS and GLONASS, countries like China, European Union and Japan are trying to have their own full-fledged or partial constellations.
Thus IRNSS system is important for securing sovereignty of India and adds a strategic edge to India’s preparedness for war by providing:

• position accuracy of better than 20 m over Indian region
• and an area extending about 1500 sq km around India.

Some Facts:
• IRNSS constellation consists of three Geostationary Earth Orbit (GEO) spacecraft and four spacecraft in Geosynchronous orbit inclined at 29 deg.
• It would provide two types of services, namely, Standard Positioning Services (SPS) - provided to all users - and Restricted Services (RS), provided to authorize users.
IRNSS-1F
• 6th navigation satellite of the seven satellites constituting the IRNSS space segment.
• Similar configuration to that of its predecessors

• • Some Features:
  
• It has two solar arrays which consist of 4 Ultra triple Junction Solar Cells that can generate about 1660 Watts of Electrical Power
•  It has sun and stars sensors as well as gyroscopes that provide orientation reference for the satellite
•  It has specially designed thermal control schemes necessary for some of the critical elements such as atomic clock
•  AOCS: Attitude and Orbit Control System: maintains the satellite orientation with the help of reaction wheels, magnetic torquers and thrusters
•  Propulsion system consists of a Liquid Apogee Motor (LAM) and thrusters
•  Will be launched into a sub geosynchronous transfer orbit (GTO) with a 284km perigee and 20,657km apogee with an inclination of 17.86 degree wrt equatorial plane
• Finally it will be placed in geostationary orbit at 32.5 degree east.

IRNSS -1F carries two types of payloads:
• navigation payload: will transmit navigation service signals to the users and also has a highly accurate Rubidium atomic clock
• CDMA payload: consists of a transponder which facilitates accurate determination of the range of the satellite.
• It also carries Corner Cube Retro Reflectors (CCRR) for laser ranging.

By: Vishal