ISRO's Polar Satellite Launch Vehicle, PSLV-C22, successfully launched IRNSS-1A, the first satellite in the Indian Regional Navigati...
ISRO's Polar Satellite Launch Vehicle, PSLV-C22, successfully launched IRNSS-1A, the first satellite in the Indian Regional Navigation Satellite System (IRNSS), in the early morning hours of July 2, from Satish Dhawan Space Centre, Sriharikota. This is the twenty third consecutively successful mission of PSLV.
The 'XL' version of PSLV with six extended solid strap-on motors was used for the mission. Previously, the same configuration of the vehicle was used thrice to launch Chandrayaan-1, GSAT-12 and RISAT-1 satellites.
At the completion of the countdown, PSLV-C22 lifted off from the First Launch Pad at 23:41 hrs IST on July 1, with the ignition of the first stage and four strap-on motors of the launch vehicle. The important flight events, namely, stage and strap-on ignitions, heat-shield separation, stage and strap-on separations and satellite injection took place exactly as planned.
After a flight of 20 minutes 17 seconds, the IRNSS-1A Satellite, weighing 1425 kg, was injected to the intended elliptical orbit of 282.46 km X 20,625.37 km.
After injection, the solar panels of IRNSS-1A were deployed automatically. ISRO's Master Control Facility (at Hassan, Karnataka) assumed the control of the satellite. In the coming days, five orbit maneuvers will be conducted from Master Control Facility to position the satellite in its Geosynchronous Circular Orbit at 55 deg East longitude.
IRNSS-1A is the first of the seven satellites constituting the space segment of the Indian Regional Navigation Satellite System. IRNSS is an independent regional navigation satellite system designed to provide position information in the Indian region and 1500 km around the Indian mainland. IRNSS would provide two types of services, namely, Standard Positioning Services (SPS) - provided to all users - and Restricted Services(RS) provided only to authorised users.
The entire IRNSS constellation of seven satellites is planned to be completed by 2015-16.
IRNSS will have a network of twenty one ranging stations geographically distributed primarily across India. They provide data for the orbit determination of IRNSS satellites and monitoring of the navigation signals.
The ISRO Navigation Centre (INC), has been established at Indian Deep Space Network (IDSN) complex at Bangalore, for providing the time reference,generation of navigation messages and monitoring and control of ground facilities including ranging stations of IRNSS. It hosts several key technical facilities for supporting various navigation functions.
Key to the navigation support is the time reference to which all ground systems and the satellite clocks are synchronised. This time reference is generated by the high precision timing facility located at INC. This timing facility is equipped with high stability,high precision atomic clocks to provide stable and continuous time reference to the navigation system.
The data from the ranging/monitoring stations is sent to the data processing facility at INC where it is processed to generate the navigation messages. The navigation messages are then transmitted from INC to IRNSS satellites through the spacecraft control facility at Hassan/Bhopal. The state ofthe art data processing and storage facilities at INC enable swift processing of data and support its systematic storage.
INC is connected to the ranging stations and to the satellite control facilities through two highly reliable dedicated communication networks consisting of satellite and terrestrial links. The hub for the satellite communication links is hosted at INC.
