Indian Regional Navigation Satellite System
|This article is outdated. (October 2015)|
|Country of origin||India|
|Satellites in orbit||5|
|Orbital height||36,000 km (22,000 mi)|
The Indian Regional Navigation Satellite System or IRNSS is an indigenously developed Navigation Satellite System that is used to provide accurate real-time positioning and timing services over India and region extending to 1500 km around India. The fully deployed IRNSS system consists of 3 satellites in GEO orbit and 4 satellites in GSO orbit, approximately 36,000 km altitude above earth surface. Though the full system comprises nine satellites, including two on the ground as stand-by. The requirement of such a navigation system is driven because access to foreign government-controlled global navigation satellite systems is not guaranteed in hostile situations, as happened to the Indian military depending on American GPS during the Kargil War. The IRNSS would provide two services, with the Standard Positioning Service open for civilian use, and the Restricted Service (an encrypted one) for authorised users (including the military).
IRNSS would have seven satellites, out of which five are already placed in orbit. The constellation of seven satellites is expected to operate from 2016 onwards.
As part of the project, ISRO opened a new satellite navigation center within the campus of ISRO Deep Space Network (DSN) at Byalalu, in Karnataka on 28 May 2013. A network of 21 ranging stations located across the country will provide data for the orbital determination of the satellites and monitoring of the navigation signal.
A goal of complete Indian control has been stated, with the space segment, ground segment and user receivers all being built in India. Its location in low latitudes facilitates a coverage with low-inclination satellites. Three satellites will be in geostationary orbit over the Indian Ocean. Missile targeting could be an important military application for the constellation.
The total cost of the project is expected to be ₹1420 crore (US$209 million), with the cost of the ground segment being ₹300 crore (US$44 million). Each satellites costing ₹150 crore (US$22 million) and the PSLV-XL version rocket costs around ₹130 crore (US$19 million) . The seven rockets would involve an outlay of around ₹910 crore (US$134 million). The IRNSS signal has been released for evaluation in Sep 2014
In April 2010, it was reported that India plans to start launching satellites by the end of 2011, at a rate of one satellite every six months. This would have made the IRNSS functional by 2015. But program was delayed. India also launched 3 new satellites into space to supplement this.
Seven satellites with the prefix "IRNSS-1" will constitute the space segment of the IRNSS. IRNSS-1A, the first of the seven satellites of the IRNSS constellation, was launched on 1 July 2013. IRNSS-1B was launched on 4 April 2014 at 17:14 IST on board the PSLV-C24 rocket. The satellite has been placed in geosynchronous orbit. IRNSS-1C was launched on 16 October 2014, IRNSS-1D on 28 March 2015 and IRNSS-1E was launched on 20 January 2016. Of the remaining two satellites, IRNSS-1F has a planned launch in March 2016 and IRNSS-1G should be in orbit by April 2016  and by middle of 2016, India will have the full navigational satellite system in place.
The proposed system would consist of a constellation of seven satellites and a support ground segment. Three of the satellites in the constellation will be located in geostationary orbit at 32.5° East, 83° East, and 131.5° East longitude. Two of the GSOs will cross the equator at 55° East and two at 111.75° East. Such an arrangement would mean all seven satellites would have continuous radio visibility with Indian control stations. The satellite payloads would consist of atomic clocks and electronic equipment to generate the navigation signals.
IRNSS signals will consist of a Special Positioning Service and a Precision Service. Both will be carried on L5 (1176.45 MHz) and S band (2492.028 MHz). The SPS signal will be modulated by a 1 MHz BPSK signal. The Precision Service will use BOC(5,2). The navigation signals themselves would be transmitted in the S-band frequency (2–4 GHz) and broadcast through a phased array antenna to maintain required coverage and signal strength. The satellites would weigh approximately 1,330 kg and their solar panels generate 1,400 watts. The system is intended to provide an absolute position accuracy of better than 10 meters throughout Indian landmass and better than 20 meters in the Indian Ocean as well as a region extending approximately 1,500 km around India.
The ground segment of IRNSS constellation would consist of a Master Control Center (MCC), ground stations to track and estimate the satellites' orbits and ensure the integrity of the network (IRIM), and additional ground stations (TT&C stations) to monitor the satellites with the capability of issuing radio commands to them. The MCC would estimate and predict the position of all IRNSS satellites, calculate integrity, makes necessary ionospheric and clock corrections and run the navigation software. In pursuit of an independent system, an Indian standard time infrastructure would also be established.
IRNSS-1A was the first navigational satellite in the Indian Regional Navigation Satellite System series of satellites to be placed in geosynchronous orbit. It was built at ISRO Satellite Centre, Bangalore, costing ₹125 crore (US$18 million). It has a lift-off mass of 1380 kg, and carries a navigation payload and a C-band ranging transponder, which operates in L5 band (1176.45 MHz) and S band (2492.028 MHz). An optimised I-1K bus structure with a power handling capability of around 1600 watts is used and is designed for a ten-year mission. The satellite was launched on-board PSLV-C22 on 1 July 2013 from the Satish Dhawan Space Centre at Sriharikota.
IRNSS-1B is the second out of seven in the Indian Regional Navigation Satellite System. It was very precisely and successfully placed in its orbit through PSLV-C24 rocket on 4 April 2014.
IRNSS-1C is the third out of seven in the Indian Regional Navigation Satellite System series of satellites. The satellite was successfully launched using India's PSLV-C26 from the Satish Dhawan Space Centre at Sriharikota on 16 October 2014 at 1:32 am.
IRNSS-1D is the fourth out of seven in the Indian Regional Navigation Satellite System series of satellites system. It was successfully launched using India's PSLV-C27 on 28 March 2015 at 5:19 pm.
IRNSS-1E is the fifth out of seven in the Indian Regional Navigation Satellite System series of satellites system. It was successfully launched on January 20, 2016 using India's PSLV-C31 at 09:31 am.
IRNSS-1F and IRNSS-1G
IRNSS-1F will be the sixth and IRNSS-1G will be seventh of the Indian Regional Navigation Satellite System series of satellites. Their launches are planned for March and April 2016.
- BeiDou Navigation Satellite System
- Galileo (satellite navigation)
- Geosynchronous Satellite Launch Vehicle
- Global Positioning System
- GPS Aided GEO Augmented Navigation
- Satellite navigation
- "Orbit height and info".
- "Isro to launch 5th navigation satellite on Jan 20, first in 2016".
- Srivastava, Ishan (5 April 2014). "How Kargil spurred India to design own GPS". The Times of India. Retrieved 9 December 2014.
- "ISRO opens navigation centre for satellite system". Zeenews.com. 2013-05-28. Retrieved 30 June 2013.
- "India Making Strides in Satellite Technology". Defence News. Retrieved 26 July 2012.
- "India's first ever dedicated navigation satellite launched". DNA India. 2 July 2013. Retrieved 24 July 2013.
- "India's first dedicated navigation satellite placed in orbit". NDTV. 2 July 2013. Retrieved 24 July 2013.
- S. Anandan (10 April 2010). "Launch of first satellite for Indian Regional Navigation Satellite system next year". Beta.thehindu.com. Retrieved 2010-12-30.
- H. Pathak. "3 Satellites To Be Launched By ISRO".
- "ISRO's Future programme". ISRO. Retrieved 18 May 2013.
- "Countdown begins for PSLV-C22 launch". thehindubusinessline.com. Retrieved 2013-06-29.
- "Isro successfully launches navigation satellite IRNSS-1B". Times Of India. Retrieved 4 April 2014.
- "ISRO puts India’s Navigation satellite IRNSS 1B into orbit". IANS. news.biharprabha.com. Retrieved 4 April 2014.
- "India launches 5th navigation satellite IRNSS-1E powered by PSLV rocket". http://www.hindustantimes.com/. Retrieved 2016-01-20. External link in
- "ISRO: All 7 IRNSS Satellites in Orbit by March". gpsworld.com. 2015-10-08. Retrieved 2015-11-12.
- "First IRNSS satellite by December". Magazine article. Asian Surveying and Mapping. 5 May 2009. Retrieved 2009-05-05.[dead link]
- A. Bhaskaranarayana Director SCP/FMO & Scientific Secretary Indian Space Research Organisation – Indian IRNSS and GAGAN
- "IRNSS-1A". n2yo. Retrieved 26 July 2013.
- "IRNSS". space.skyrocket.de. Retrieved 2012-04-08.
- "ISRO Forthcoming Satellite launches". ISRO. Retrieved 24 September 2011.
- "IRNSS-1A". ISRO. 1 July 2013. Retrieved 2 August 2013.
- "India to launch first navigational satellite on June 12". Zee news. 18 May 2013. Retrieved 18 May 2013.
- "India’s First Navigational Satellite IRNSS -1A to be Launched in June - International Business Times". Ibtimes.co.in. Retrieved 18 May 2013.
- "Indian PSLV successfully launches IRNSS-1A navigation satellite". Zee News. 2 July 2013. Retrieved 1 July 2013.
- "India launches second navigation satellite IRNSS 1B". Business Standard. Retrieved 4 April 2014.
- "ISRO getting ready for IRNSS 1C launch next month". Economic Times.
- "ISRO to launch IRNSS 1C on October 10". IBN Live. Retrieved 3 October 2014.
- "'All seven satellites of IRNSS to be in orbit by March 2016'". Business Standard. October 29, 2015. Retrieved November 1, 2015.
- "Deccan Chronicle: PSLV launch countdown begins at SHAR in Nellore".