India's Navigation Satellite System Challenges
India's space agency recently faced another setback with the partial failure of the NVS-02 navigation satellite due to engine issues. This adds to a series of challenges the Indian Regional Navigation Satellite System (IRNSS), or Navigation with India Constellation (NavIC), has faced since its inception.
Background of IRNSS
- Conceived in 1999 post the Kargil War due to the inability to use the American GPS.
- Aimed to establish a seven-satellite constellation for defense and civilian purposes by 2016.
- The first satellite, IRNSS 1A, was launched on July 1, 2013.
Performance and Failures
- Eleven satellites have been launched since 2013, but only five are fully operational as of now.
- Issues arose from mid-2016 with the failure of rubidium atomic clocks, common in IRNSS and ESA's Galileo system.
- IRNSS-1A's atomic clocks stopped functioning, though other components remained operational.
- Subsequent satellites, including IRNSS-1C, 1D, 1E, and 1G, experienced similar clock issues.
- The recent IRNSS-1K (NVS-02) faced engine failure, further adding to the challenges.
Current Operational Status
- Estimated four fully operational satellites: IRNSS-1B, 1F, 1I (replacement for failed 1A), and 1J (replacement for partially failed 1G).
- Some estimates suggest IRNSS-1C is only partially operational.
- Newer satellites like 1H and 1I feature modified clocks, while NVS-01 and NVS-02 include indigenous and foreign clocks.
Importance of IRNSS/NavIC
- Provides two types of services: Standard Positioning for commercial use and Restricted Service for defense.
- Offers positioning accuracy better than 20 meters within India and surrounding regions.
- Essential for military reliability, unlike global systems which restrict precise services to allied forces.
Future Prospects and Developments
- ISRO aims to increase NavIC's ubiquity by collaborating with mobile and vehicle manufacturers.
- In December 2023, Qualcomm agreed to incorporate NavIC in some chipsets following the successful NVS-01 launch.
- ISRO plans to launch three more second-generation satellites (NVS-03, 04, 05) to enhance the NavIC system.
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