The Indian Space Research Organization is set to test its sophisticated, indigenously-built, multi-object tracking radar (MOTR) on a rocket flight next month while formal commissioning is expected to take three months time.
Multi-Object Tracking Radar (MOTR)
The totally indigenous Rs. 240-crore multi-object tracking radar, which was developed and built by scientists of the Indian Space Research Organisation (ISRO). The new radar which will operate from Sriharikota range can track nearly 10 objects simultaneously in a distance as far as 1000 km in space, while the conventional radars spot a single object at a time. This is useful in many ways since it can detect 10 objects at a time and in case space debris is approaching an Indian satellite, the path of satellite can be diverted to avoid collision and damage,to Range safety, Impact point monitoring, recovery and re-entry missions.
The MOTR will track different stages of launch vehicles simultaneously during nominal and non-nominal missions. The tracking data will be used for computing the Instantaneous Impact Points (IIPs) of the descending/separated objects of the launch vehicle, more accurately.
The Rs 245 crore MOTR can be termed as the classic example of a ‘Make in India’ project. A similar radar would cost around Rs 800 crore in the international markets and is mainly used for defence purposes.
The configuration of MOTR is derived based on long range tracking requirement of 50 cm x 50 cm object size at a slant range of 1000 km for objects and 30 cm x 30 cm size at a slant range of 800 km in LEO for space-debris. The MOTR operates in L-band frequency (1.3 to 1.4 GHz) with active phased array antenna, capable of tracking ten objects simultaneously. The radar is designed to have a maximum peak power of 830 kW with 4608 radiating antenna elements.
Further, MOTR will also provide the data related to close approach of space debris to the remote sensing satellites in Low Earth Orbit (LEO) and to plan the collision avoidance manoeuvres of these satellites, thus contributing to the safe operation of ISRO’s Space Assets and Space Situational Awareness.
In its bid to acquire advanced technologies, India has joined the select group of countries that have rare and the latest technologies for tracking multiple objects moving in space with the help of a highly-sophisticated radar. With the new facility, India will be joining nations like the US, Israel, Japan and Canada, which have similar advanced technology. MOTR can track 10 different objects simultaneously with a range of nearly 1,000 km. The existing radars have a range of 300 to 400 km.
The Rs. 245-crore project was completed within the scheduled timeframe with the help of scientists drawn from various ISRO centres. Unlike conventional radars, MOTR has a stationary antenna, which has electronic beam steering capability.
Isro has faced the issue of changing the path of its satellites nearly 12 times in the past when the space debris moved closely to these objects. Space debris data is mostly taken from the National Aeronautics Space Agency (NASA) but the newly acquired technology will help in keeping a watch on Isro’s space assets on a daily basis.
“The software for operating the system and analysing the data was developed in-house and around Rs 100 crore value could be put for that,” said V Seshagiri Rao
With this radar, Isro acquires the capacity to handle its future missions involving atmospheric re-entry of space modules, having a protective eye on its space assets and track space debris. Currently Isro uses the space debris data provided by US space agency Nasa. The commissioning of MOTR would provide real-time data for Isro.
The project got the green signal in 2012 with a target to get the radar ready by February 2015 which was achieved.
1. A Multi-Object Tracking Radar or MOTR is being realized indigenously. Excepting the radome that houses the radar, all other systems were domestically sourced. The radome which is radio frequency transparent was not available in the country.
2. The new radar can track nearly 10 objects simultaneously.(50 cm x 50 cm object size at a slant range of 1000 km and 30 cm x 30 cm size at a slant range of 800 km in LEO for space-debris.)
3. The phased array radar antenna is stationary while its beam generated by 4,608 radiating elements can be steered.
4. The radar weighing 35 tonnes, 12-metre long and 8 metre tall rectangular could be turned in different directions and will be used to meet the range safety purposes during a rocket launch here.
According to Subba Rao, it is important to track all the targets of a rocket simultaneously for which MOTR would be used. The radar can also be used for vertical wind profiling and also be used at airports.
Sources: The Times of India, The Hindu