SBAS Knowledge Base

Source - GAGAN SBAS Operation

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Source - GAGAN SBAS Operation

Scope of this note

This note is the knowledge base’s institutional source anchor for GAGAN (GPS Aided GEO Augmented Navigation), India’s Satellite-Based Augmentation System.

Boundary:

  • This note is not itself an authoritative GAGAN technical specification.
  • Exact system performance values, coverage boundaries, and operational approval conditions must be verified against official DGCA India, AAI, and ISRO publications.
  • This note extracts and anchors verified signals from the ICAO APAC ITF/7 working context and from AAI public documentation.
  • This note does not imply that GAGAN service is available outside Indian FIRs and airspace.

Primary source

ICAO APAC ITF/7 IP05b — GAGAN SBAS Based LPV Procedure Implementation Update in India

Source: India presentation to Seventh GBAS/SBAS Implementation Task Force (ITF/7), hosted by ICAO APAC, 14–16 May 2025.

URL: https://www.icao.int/sites/default/files/APAC/Meetings/2025/2025%20GBASSBAS%20ITF7/4-Information%20Papers/A4-IP05b-GAGAN-SBAS-BASED-LPV-PROCEDURE-IMPLEMENTATION-UPDATE-IN-INDIA.pdf

Authors: India (presented by AAI/ISRO)

Verified signals from ITF/7 IP05b

System certification and operational status

|| Field | Verified signal | ||---|---| || Certifying authority | DGCA India | || Operational certification date (RNP 0.1) | 2013 | || APV I operational certification date | 2015 | || Coverage scope | Indian FIRs (RNP 0.1); Indian Landmass (APV I) | || Governing standard context | ICAO Annex 10 SARPs |

Architecture — ground segment

Source signals: ITF/7 IP05b paragraph 1.2

  • Fifteen ground reference stations (INRES): Ahmedabad, Bengaluru, Trivandrum, Port Blair, Guwahati, Delhi, Porbandar, Dibrugarh, Jaisalmer, Bhubaneshwar, Kolkata, Gaya, Nagpur, Jammu, Goa
  • Two Master Control Centres (INMCC): Bengaluru (GBC) and Delhi (GBM)
  • Three uplink stations (INLUS): two at Bengaluru, one at Delhi
  • Upgrade year (frequency standard): 2020 — Microsemi 5071A High Precision Frequency Standard (HPFS) installed at all three INLUS
  • Upgrade year (signal generator): 2022 — NovAtel GUS Type-I Signal generator installed at all three INLUS
  • Reference station upgrade (receiver): Novatel G-III receiver and IBM S914 server installed at all 15 INRES (phased 2020–2024); DFO/DFMC ready

Architecture — space segment

Source signals: ITF/7 IP05b paragraph 1.2; AAI public FAQ page

  • GSAT-8: Geostationary satellite, PRN code 127, 55° E longitude
  • GSAT-10: Geostationary satellite, PRN code 128, 82° E longitude
  • GSAT-15: Geostationary satellite, PRN code 132 (in-orbit spare), 83° E longitude

Ionospheric monitoring

Source signal: ITF/7 IP05b paragraph 2.4

  • Indian Ionosphere monitoring network upgraded with Septentrio PolaRx5S receiver
  • Supports multi-frequency, multi-constellation ionospheric monitoring

LPV procedure status (as of ITF/7, May 2025)

Source signals: ITF/7 IP05b paragraphs 3.1–3.2

  • ICAO SBAS channel numbers assigned to India: 53
  • LPV procedures published: 23 procedures at 15 airports
  • LPV procedures in simulator validation and flight trials: 12 procedures
  • LPV procedures under design/development: 18 procedures
  • Published procedure AIP link: https://aim-india.aai.aero/eaip-v2-02-2025/index-en-GB.html (select AD_2 under Part 3 — Aerodromes)
  • ICAO APAC SBAS map: https://www.icao.int/APAC/Pages/GBAS-SBAS-MAP.aspx
  • Flight inspection: AAI Flight Inspection Unit aircraft certified by DGCA India for GAGAN LPV procedure validation

Workshop hosting

Source signal: ITF/7 IP05b paragraph 4

  • India to host SBAS/GBAS Workshop for Airspace Users in Bengaluru, 14–16 October 2025

What this source can currently anchor

With ITF/7 IP05b verified as a public ICAO document:

  • GAGAN is DGCA India certified, declared operational for RNP 0.1 services (2013) and APV I services (2015)
  • GAGAN ground segment consists of 15 INRES, 2 INMCC, 3 INLUS
  • GAGAN space segment consists of GSAT-8 (PRN 127), GSAT-10 (PRN 128), GSAT-15 (PRN 132)
  • GAGAN reference stations are DFO/DFMC ready as of the upgrade completed 2024
  • 23 LPV procedures published at 15 Indian airports as of May 2025
  • India is actively developing additional LPV procedures
  • India hosts the SBAS/GBAS Workshop for Airspace Users in October 2025

What this source must not be used for yet

Do not use this note alone to publish:

  • GAGAN coverage extent or availability outside Indian FIRs and landmass
  • LPV procedure minima, decision heights, or approach eligibility
  • Specific DGCA approval conditions or operational authorization details beyond what IP05b states
  • Comparative performance claims with other SBAS providers
  • Claims about GAGAN’s future capacity or expansion plans beyond IP05b

Source weaknesses and extraction gaps

The following require additional source extraction:

  • GAGAN signal-in-space accuracy and integrity performance figures (not yet extracted from official GAGAN performance reports)
  • GAGAN service volume or coverage area definition (not yet extracted from AAI service documentation)
  • Specific LPV procedure minima at individual airports (requires AIP/procedure chart sources)
  • GAGAN operational experience or service disruption history (not yet extracted)
  • Comparison with other SBAS providers on performance metrics

Relationship to other source notes

|| Source note | Relationship to GAGAN source note | ||---|---| || Source - ICAO Annex 10 Volume I GNSS SBAS | Annex 10 SARPs define the SBAS system-level requirements that GAGAN implements | || Source - RTCA DO-229 | DO-229F defines airborne equipment requirements for LPV operations that GAGAN supports | || Source - ICAO APAC GBAS-SBAS Implementation Forums | ITF/7 IP05b is the source; ITF is the regional coordination forum | || Source - SBAS Service Providers | Source - SBAS Service Providers is the service-provider family anchor; this note is its GAGAN-specific child | || Source - ICAO Doc 9849 | Doc 9849 provides ICAO GNSS implementation guidance context for GAGAN’s role |

See also

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