Indian GNSS Paradigm A.S.GANESHAN. Program Director - SATNAV ISAC/ISRO, Bangalore. SCPNT Nov.2015 STANFORD PALOALTO 1

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1 Indian GNSS Paradigm Dr. S. PAL [FIEEE, FNAE, FNASc, Dist. Fellow IETE, IET(UK), MIAA(Paris)] Vice Chancellor Defence Ins6tute of Advanced Technology, (Deemed University), Girinagar, Pune (Former S. Dhawan Professor and Senior Advisor SATNAV- ISRO) A.S.GANESHAN Program Director - SATNAV ISAC/ISRO, Bangalore SCPNT Nov.2015 STANFORD PALOALTO 1

2 Indian GNSS Paradigm Ø Satellite Posi6oning System (SPS) started in First SPS was used On Board IRS- P4. In- house orbit determina6on sowware SANGAM was developed. Ø Satellite Based Augmenta6on System (SBAS) studies were undertaken along with AAI in GAGAN project was formed in Technology Demonstra6on System (TDS) was over in 2007 and Final Opera6onal Phase (FOP) from year 2009 to Ø GAGAN cer6fied for APV1.0/1.5 in April, Ø Indian Regional Naviga6on Satellite System (IRNSS) studies were started in Project formula6on was completed in First IRNSS satellite was launched on 1st July, Constella6on of seven satellites is slated to be completed by Ø Collabora6ve studies and efforts have been con6nuously undertaken with GPS, GLONASS, EGNOSS/GALILEO and JAXA. Ø Ionospheric & Tropospheric Studies and modeling India may become a great user of GNSS for GIS, mobile, survey, mining, fishing industry, avia6on, road, rail transport etc. 2

3 Major Specifica6ons of SPS Description Specification Remarks Type of System GPS Receiver, L1, C/A (6/8/10/12 Channel SPS) L1 C/A, L2C & GAGAN (21 Channel SPS) In Future, this could change in a Multi-GNSS environment No of Channels 6/8/10/12/21 More Channels need More On-board Resources Time To First Fix 480/100/85/80 (Sec) Faster is Better Velocity ± 10 km (Doppler range of about 100KHz at L1 frequency) LEO Satellites typically orbit at 28,000 km/h speed Acceleration 5g High during launch/reentry. On-Orbit much lesser. On-board storage 2 Orbits Data Down linked at 16 kbps through a Ground Station S/C Interface MIL-1553B or Serial Mission Requirements 3

4 GNSS- based Satellite Posi6oning System GNSS Receiver is used to compute precise orbit of LEO satellites. The major challenges are Very high velocity Wider visibility angle Frequent memory/data corrup6on Auto- recovery 24/7 opera6on for many years Specialized acquisi6on tracking algorithms, dual- redundant dissimilar hardware, screening and special processes are used to meet the above challenges. GNSS- based SPS are successfully flown since 1999 in many missions including IRS P4, TES, IRS P6, IRS P5, CARTOSAT, SRE, Ocean Sat etc. Further GNSS Receiver is used in the PSLV launch vehicles star6ng from C8. 4

5 SPS: Performance Enhancements ( ) (Posi6on Accuracy in meters & No. of Channels) Accuracy Channels Precise Transfer of Time SPS provides a mechanism of precise time transfer for On Board Timer (OBT) and to Payloads (Science Missions). Plot showing achieved time transfer accuracy of better than 1µsec for ASTROSAT mission. 5

6 Naviga6on- Air, Sea and Land Posi6oning Applica6ons Survey Image Correc6on GIS Timing Surveillance/Fleet Monitoring 6

7 SBAS System Universally 15.3 dbi 15 dbi 17.1 dbi 15 dbi 16.8 dbi 7

8 System Configura6on of GAGAN 8

9 Common coverage of GAGAN GEO satellites GAGAN payload is a hosted payload already opera6onal through GSAT- 8 (55 o E), GSAT10 (83 o E) opera6ng in L1 ( MHz) and L5 ( MHz) bands GSAT- 15 (93.5 o E) :To be launched GSAT- 8 Launched on 21 st May,2011 GSAT- 10 Launched on 29 th Sept,2012 GSAT- 1 5 Slated for launch by Nov,2015 broadcasjng GAGAN signal with PRN127 broadcasjng GAGAN signal with PRN128 Will broadcast GAGAN signal with PRN 139 Antennas:0.6 m C- band and 0.8m X 0.8m L- band helical antenna Antennas:0.7m & 0.9m parabolic for C band, sixteen element helical antenna for L band 0.7m prime focal Rx & 0.8m X 0.8m helix array Tx 9

10 GAGAN Ground Segment 15 Indian Reference Sta6ons (INRES) at Ahmedabad, Bengaluru, Bhubaneswar, Kolkata, Delhi, Dibrugarh, Gaya, Goa, Guwaha6, Jaisalmer, Jammu, Nagpur, Porbandar, Port Blair, Trivandrum. 2 Indian Master Control Centers (INMCC) at Bengaluru. 3 Indian Land Uplink Sta6ons (INLUS) at Bengaluru and Delhi. 4 Data Communica6on Networks (2 OFC + 2 VSAT) 10

11 GAGAN TDS Posi6on Plots for 24 hrs 11

12 The objective of GAGAN-FOP was to realize a certified and operational SBAS for all phases flight path over the Indian Flight Information Region (FIR) to provide air navigation services. Certified Performance: Navigation Performance (RNP) 0.1 en route navigation within Indian FIR Approach with Vertical Guidance (APV)-1/1.5 precision approach over Indian FIR. 12

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14 GAGAN Cer6fica6ons GAGAN has been cer6fied by Directorate General of Civil Avia6on (DGCA) for the provision of RNP 0.1 and APV 1.0 services. RNP 0.1 Service Cer6fica6on: 30- Dec Commissioning: 14- Feb APV 1.0 Service Cer6fica6on: 21- Apr Commissioning: 19- May GEO s GSAT- 8, GAST- 10 and GSAT- 15 carry GAGAN Payload. 14

15 Indian Regional Naviga6onal Satellite System (IRNSS) Constella6on IRNSS- 1A IRNSS- 1B IRNSS- 1C IRNSS- 1D

16 IRNSS is being realized by the Indian Space Research Organiza6on (ISRO). The main objec6ve is to provide Reliable Posi6on, Naviga6on and Timing services. Provides the user with a targeted posi6on accuracy of beler than 20 m over India and the region extending to about 1500 km around India. Provides Standard Posi6oning Service (SPS) and an Encrypted Restricted Service (RS). 16

17 IRNSS Architecture IRNSS- 1B GEO at 32.5 E GSO at 55 E IRNSS- 1A IRNSS- 1C GEO at 83 E IRNSS- 1D GSO at E GEO at E 17

18 Space segment IRNSS Architecture Seven satellites configurajon, 3 SVs in Geo- StaJonary orbit ( 32.5, 83 and East), 4 SVs are in GEO Synchronous orbit placed at inclinajon of 29 (two each at 55 and East Longitude crossings ) The satellites are specially configured for NavigaJon. IRNSS satellites are to be launched by the Indian launcher PSLV. Payloads transmit on L5 ( MHz MHz) and S ( MHz MHz) bands. Ground Segment 4 IRNSS CDMA Ranging StaJon (IRCDR) MulJple LASER Tracking StaJons 15 IRNSS Range & Integrity Monitoring StaJons (IRIMS) IRNSS Spacecrab Control Facility (IRSCF) IRNSS NavigaJon Centre (INC) IRNSS Network Time Centre (IRNWT) User Segment Includes a dual- frequency (L5 and S band) IRNSS receiver, a GNSS receiver compajble with IRNSS, GPS, GLONASS and Galileo. 18

19 IRNSS Satellites Specifica6ons IRNSS 1A IRNSS 1B IRNSS 1C IRNSS 1D Launch Date 1 st July, th April, th Oct, th March, 2015 Launch Vehicle PSLV- C22 PSLV- C24 PSLV- C26 PSLV- C27 Orbit GSO at 55 E with 29 inclinajon GSO at 55 E with 29 inclinajon GEO at 83 E GSO at E with 30.5 inclinajon Lib- OFF Mass (Kg) Dry Mass (Kg) Power GeneraJon Capability (W) Physical Dimensions 1.58 m X 1.50 m X 1.50 m 1.58 m X 1.50 m X 1.50 m 1.58 m X 1.50 m X 1.50 m 1.58 m X 1.50 m X 1.50 m Mission Life 10 years 10 years 10 years 10 years 19 All the seven satellites of IRNSS are expected to be in orbit by 2016.

20 IRNSS- 1D Undergoing Solar Panel Deployment Test PSLV C- 24 Payload Fairing enclosing the IRNSS- 1B IRNSS- 1C spacecraw undergoing EMI- EMC Tests IRNSS- 1C spacecraw undergoing Vibra6on Test 20

21 IRNSS Coverage 17 dbi Primary Service Region Polygon for IRNSS- 1C: India mainland and surrounding 1500 km Extended service Region Polygon: Long. 30 E to 130 E, Lat. 30 S to 50 N 16 dbi 21

22 IRNSS Coverage IRNSS Coverage Area HDOP & VDOP (99%) for the Proposed Constella6on GEO 34,83,132 GSO 55(55,235), 111(111,291) User Mask Angle 5deg 22

23 Possible Expansions of IRNSS (Study) 23

24 IRNSS Signal Plan Navigation Down Link Signals 24

25 IRNSS Signal Specifica6ons L5 S SPS RS SPS RS Centre Frequency (MHz) Chipping Rate (Mcps) ModulaJon Type BPSK(1) BOC(5,2) BPSK(1) BOC(5,2) Data/Symbol Rate (sps) Bandwidth (MHz) Min. Required Power (dbw) Max. Required Power (dbw) Max. CorrelaJon Loss (db) Jamming Margin (db)

26 IRNSS Frame Structure 26

27 IRNSS Ground Segment 27

28 IRNSS Ionospheric Correc6ons v Ionospheric effects on signal propagajon is the largest error source for single- frequency IRNSS users operajng on L5. v Following figures show the total electron count (TEC) for a typical lines- of- sight on L5 over the course of a day. Ionospheric delay comparison (dual- versus single- frequency grid) on L5 over 24 hours Ionospheric delay comparison (dual- versus single- frequency coefficient) on L5 over 24 hours 28

29 IRNSS Ionospheric Correc6ons Posi6on errors for single- frequency user equipment using grid- based correc6ons compared with dual- frequency receivers Posi6on errors for single- frequency user equipment using coefficient- based correc6ons compared with dual- frequency receivers RSS Posi6on Error at Bangalore and Bhopal Reference Sta6ons with 4 IRNSS Satellites 29

30 IRNSS Network Timing System(IRNWT) The IRNSS Jming facility generates the free running Jme scale is designated Free- (n), where n is either A or B depending on whether it is the online or backup system. The steered Jme scale is designated Steered- (n) or System Jme. The physical realizajon of the steered Jme scale is IRNWT, which is a leap second free Jme scale. This will be synchronized & steered to TAI from internajonal Jme lab maintained with in accuracy bejer than 25ns at any instant of Jme over a year. This will be/ can also be called as TAI aber synchronizajon. IRNWT is normally delivered by the primary system, and it is delivered by the redundant system in case the primary fails. Top level diagram of IRNWT facility configuration 30

31 Applica6on Areas KEY AREAS Ø Ganga Cleaning Mission: Mapping the River Bed and En6re Basin Ø Crop Forecas6ng Ø Iden6fying Poten6al Fisheries Zones Ø Wasteland Development Ø Preparing Master Plan for Ci6es Ø Satellites to provide Cri6cal Data on Natural Resources of the Country Ø Environment Impact Assessment Ø BIG (BHUVAN + IRNSS + GAGAN) Ø Forest Fire Alert System Ø Forest Cover Monitoring Ø GIS- based Infrastructure Planning Ø Geo- morphological Mapping for Mining Ø Mapping of Protected Areas and Coastal Zones Ø Toll Informa6on System for Na6onal Highways Ø Site Management Plan for Tourist Places under ASI, Geo- tagging and 3D Ø Feeding into the Flagship Programs of India Ø Visualiza6on Ø Water Bodies and Ground Water Prospects Mapping Ø Traffic Control, Scien6fic Research and Security Agencies Ø Disease Surveillance Ø Micro and Mini Irriga6on and Agricultural Projects Ø Micro and Mini Farming Ø Weather and Ionospheric Studies Ø Geo Dynamics 31

32 HISTORY OF NAVIGATION The great sanskrit scholar Kalidas (4 th century A.D) was the first one to imagine above land naviga6on. In his famous Sanskrit composi6on `Meghdoot, Kalidas s Yaksha instructs `Megha,how to navigate from Ramagiri to Alkapuri. He used complete Bio- Sphere as Naviga6onal Control Points. 32

33 T H A N K S