GK ARTICLE : INDIAN REGIONAL NAVIGATION SATELLITE SYSTEM (IRNSS)

INDIAN REGIONAL NAVIGATION SATELLITE SYSTEM (IRNSS)

IRNSS is an independent regional navigation satellite system being developed by India. It is designed to provide accurate position information service to users in India as well as the region extending up to 1500 km from its boundary, which is its primary service area. The Extended Service Area lies between primary service area and area enclosed by the rectangle from Latitude 30 deg South to 50 deg North, Longitude 30 deg East to 130 deg East. 

IRNSS will provide two types of services, namely, Standard Positioning Service (SPS) which is provided to all the users and Restricted Service (RS), which is an encrypted service provided only to the authorised users. The IRNSS System is expected to provide a position accuracy of better than 20 m in the primary service area. 

IRNSS comprises of a space segment and a ground segment. The IRNSS space segment consists of seven satellites, with three satellites in geostationary orbit and four satellites in inclined geosynchronous orbit. IRNSS-1A, the first satellite of the IRNSS constellation, has already started functioning from its designated orbital slot after extensive on orbit test and evaluation to confirm its satisfactory performance. 

IRNSS ground segment is responsible for navigation parameter generation and transmission, satellite control, ranging and integrity monitoring and time keeping. 

The constituent elements of the ground segment are:

ü  ISRO Navigation Centre (INC) at Byalalu, is the nerve center of the IRNSS Ground Segment. INC primarily generates navigation parameters.

ü  IRNSS Range and Integrity Monitoring Stations (IRIMS) perform continuous one way ranging of the IRNSS satellites and are also used for integrity determination of the IRNSS constellation.

ü  IRNSS CDMA Ranging Stations (IRCDR) carry out precise two way ranging of IRNSS satellites.

ü  IRNSS Network Timing Centre (IRNWT) at Byalalu generates, maintains and distributes IRNSS Network Time.

ü  Spacecraft Control Facility (SCF) controls the space segment through Telemetry Tracking & Command network. In addition to the regular TT&C operations, IRSCF also uplinks the navigation parameters generated by the INC.

ü  IRNSS Data Communication Network (IRDCN) provides the required digital communication backbone to IRNSS network.

ü  Laser Ranging Stations (ILRS) is planned to be used periodically to calibrate the IRNSS orbit determined by the other techniques.

Applications of IRNSS:

A Terrestrial, Aerial and Marine Navigation

A Disaster Management

A Vehicle tracking and fleet management

A Integration with mobile phones

A Precise Timing

A Mapping and Geodetic data capture

A Terrestrial navigation aid for hikers and travellers

A Visual and voice navigation for drivers