The Indian Regional Navigation Satellite System (IRNSS) is India's independent regional navigational satellite system. It consists of a constellation of 7 satellites providing accurate real-time positioning and timing services. IRNSS aims to provide accurate position information service to users in India as well as the region extending up to 1500 km from its boundaries. It is expected to provide a position accuracy of better than 20 meters in its service area. The system is expected to provide two types of services: standard positioning service and restricted service.

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2. IRNSS
Indian Regional Navigation
Satellite System
SAAD BABAR ABBASI
MS-GNSS-02
150511011
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4. CONTENTS
BACKGROUND
WHY LAUNCHED?
SATELLITE CONSTELLATION
SATELLITE GENERATIONS
ARCHITECTURE
IRNSS SIGNAL
IRNSS COVERAGE
REFERENCE FRAME
PERFORMANCE (IRNSS vs GPS)
SERVICES
BENEFITS
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5. BACKGROUND
Approved by Government of India in May 2006
 The total cost of the project is expected to be US$209 million
In April 2010, it was reported that India plans to start launching satellites by the end of 2011,
at a rate of one satellite after every six months
This would have made the IRNSS functional by 2015, but program was delayed
The IRNSS signal has been released for evaluation in Sep 2014
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6. Why Launched?
Selective availability of GPS signal made it less effective and reliable
Access to foreign government-controlled global navigation satellite systems (GPS) is not
guaranteed in hostile situations
Indian military depending on American GPS during Wars
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7. SATELLITE CONSTELLATION
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8. SATELLITE CONSTELLATION
There are 9 satellites in total
3 satellites in GEO stationary orbit
4 satellites in GSO orbit
2 on the ground as stand-by
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9. SATELLITE GENERATIONS
IRNSS-1A was the first navigational satellite in the Indian Regional Navigation Satellite System
series of satellites to be placed in geosynchronous orbit. The satellite was launched on-board
PSLV-C22on 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-C24rocket 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-C26from the Satish
Dhawan Space Centre at Sriharikota on 16 October 2014.
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10. SATELLITE GENERATIONS
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-C27on 28 March 2015.
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
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
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11. ARCHITECTURE
The IRNSS architecture mainly consists of:
Space Segment
Ground Segment
User Segment
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12. ARCHITECTURE
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13. SPACE SEGMENT
Based on various considerations the minimum number of satellites required for IRNSS
constellation is worked out to be 7 (3 GEO and 4 GSO).
The 3 GEOs will be located at 32.5º E, 83º E and 131.5º E and the 4 GSOs have their longitude
crossings 55º E and 111.75º E (two in each plane).
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14. GROUND SEGMENT
Ground Segment is responsible for the maintenance and operation of the IRNSS constellation. The
Ground segment comprises of:
ISRO Navigation Centre
IRNSS Spacecraft Control Facility
IRNSS Range and Integrity Monitoring Stations
IRNSS Network Timing Centre
IRNSS CDMA Ranging Stations
Laser Ranging Stations
Data Communication Network
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15. USER SEGMENT
The User segment mainly consists of:
Single frequency IRNSS receiver capable of receiving SPS signal at L5 or S band
frequency
A dual frequency IRNSS receiver capable of receiving both L5 and S band frequencies.
A receiver compatible to IRNSS and other GNSS signals
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16. IRNSS SIGNAL PLAN
The first proposal for the Signal and Frequency Plan presented in November 2006 during the
First ICG Meeting in Vienna by Indian Space Research Organization (ISRO).
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18. IRNSS SIGNAL PLAN
Given the similarity with the Galileo signals in terms of services that IRNSS might be
providing, the same convention as for Galileo was employed. That is A for the PRS and B and C
for the Open Service data and pilot signals respectively
When seen in frequency spectra the overall picture of IRNSS signal would be….
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19. SPETRA OF SIGNAL IN E-5b BAND
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20. IRNSS SIGNAL PLAN
It is interesting to mention that the Indian Satellite Navigation Programme has been doing
much work in the past years on ionospheric and tropospheric modelling in the Region of India
what could mean that IRNSS does not plan to use dual frequency at least in the first
generation.
Moreover, India also plans to transmit similar signals for the S-band to those we have just
described for the L5 band.
The carrier frequency of S-band is at 2491.75 MHz. The modulation schemes and data rates
would be the same as for L5 but no final decision on the other parameters has been made yet.
In addition, it seems that India also plans to transmit signals in L1 as announced during the
second Meeting of the ICG in India, in 2007.
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21. FINAL SIGNAL PLAN OF IRNSS
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22. IRNSS CLOSE UP
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23. IRNSS COVERAGE
1,500-2,000 km’s around Indian land-mass SAARC countries can use IRNSS navigation system
SAARC members countries included are
India
Afghanistan
Bangladesh
Bhutan
Maldives
 Nepal
Pakistan
Sri Lanka
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24. IRNSS REFERNCE FRAME
IRNSS makes use of the International Terrestrial Reference System (ITRS).
The ITRS defines a geocentric system of coordinates using the System International.
An International Terrestrial Reference Frame (ITRF) is a realization of the ITRS. New ITRF
solutions are produced every few years, using the latest mathematical and surveying
techniques to attempt to realize the ITRS as precisely as possible.
 IRNSS Time is the reference time generated by IRNWT (IRNSS network timing).
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25. IRNSS PERFORMANCE
Current status with 4 satellites of IRNSS, the GDOP (Geometric Dilution of Precision varies
from 2m to 9m in a day) which means we are getting accuracy around 8m to 40m.
With 3 more satellites in IRNSS the GDOP variation would be only 3-4m and hence accuracy
will be guaranteed less than 20m throughout day in any part of India
Please note GPS is giving similar accuracy
IRNSS L5 signal is compatible with GPS new signal structure of L5c. and hence user may have
receiver with both GPS and IRNSS and get better accuracy by combing solution
IRNSS broadcast difference between IRNSS and GPS, IRNSS and GLONASS for compatibility
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26. SERVICES
Special Positioning Service (SPS) an open service without encryption and Restricted Service
Precision Service (PS) an authorized with encryption are the basic services offered by IRNSS
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27. APPLICATIONS/BENEFITS
NAVIGATION
•Boats and ships
•Heavy Equipment
•Cyclists
•Air navigation
•Automobiles
•Hikers, climbers
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28. APPLICATIONS/BENEFITS
SURVEYING & MAPPING
•Archaeology
•Geophysics and geology
•Surveying
•Mapping and geographic information systems
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29. APPLICATIONS/BENEFITS
OTHER USES
•Military Precision-guided munitions
•Mobile Satellite Communications
•GPS tracking
•Weather Prediction
•Skydiving
•Social Networking
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30. REFERENCES
www.google.com
www.navipedia.net
www.isro.gov
www.wikipedia.org
ICAO International Standards and Recommended Practices, Annex 10 to the Convention pm International Civil
Aviation, Volume I Radio Navigation Aids, Section 3.7.1: Definitions
2.Mishra Pratap& EngePer, Global Positioning System, Signals, Measurements and Performance (Ganga-
JamunaPress, Lincoln, Mass, USA), 2012, pp.-123-173
3.Parkinson Bradford W & SpilkerJames J, Global Positioning System: Theory and Applications, Volume I, by (Jr.
American Institute of Aeronautics and Astronautics Inc, USA), 2010, pp. 10-17, 478-483, 485-513.
4.KlobucharJ A, P H Doherty, M B El-Arini, Lejeune R, DehelT, de Paula E R & Rodrigues F S, IonosphericIssues
for a SBAS in the Equatorial Region, IonosphericEffects Symposium, Alexandria, Virginia, 7-9 May 2012.
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