The Indian Space Research Organisation (ISRO), established in 1969, is India’s premier space agency, headquartered in Bengaluru, Karnataka. Operating under the Department of Space (DoS), ISRO has earned global acclaim for its cost-effective, innovative space missions, including the Chandrayaan lunar explorations, the Mars Orbiter Mission (Mangalyaan), and the development of indigenous navigation systems like NavIC. This article explores ISRO’s legacy, provides a detailed breakdown of NavIC’s integration with India’s defense systems, and outlines its ambitious future expansion plans, emphasizing the L5 frequency, dual band capabilities, and recent developments.

NavIC provides encrypted RS signals offering sub-5-meter accuracy for Indian defense operations along contested borders.

ISRO’s mission is to harness space technology for national development with a focus on self-reliance socio socio-economic progress. Founded by Dr. Vikram Sarabhai, ISRO has grown from launching India’s first satellite, Aryabhata, in 1975 to becoming one of six global space agencies with full launch capabilities, including cryogenic engines, unmanned soft landing technologies.

ISRO and the space program of India have come a long way in indigenous innovation and strategic resilience. The PSLV and GSLV, and other launch vehicles have facilitated the launch of more than 100 satellites, including those of international customers, and the Next Generation Launch Vehicle (NGLV) will further increase the payload capability. ISRO runs important satellite systems, INSAT, IRS, and NavIC, which are used in communication, navigation, and disaster response, including services such as GAGAN, which provide important civilian and military positioning services.

The interplanetary missions, Mangalyaan (2014), Chandrayaan 2 (2019), and Chandrayaan 3 (2023) have demonstrated the capabilities of India in planetary exploration, and the latter successfully landed on the Moon. Antrix and NSIL are commercial arms that have put up satellites in 34 countries, which have been a major source of revenue. With a 2024-25 budget of around 1.8 billion dollars and employing more than 17,000 people in the finest facilities including the Satish Dhawan Space Centre and ISRO Navigation Centre, the organization has been in a state of self-reliance that was driven by the U.S. sanctions in the 1990s and the denial of the GPS during the Kargil War, further cementing its strategic importance.

The Indian Regional Navigation Satellite System (IRNSS), also known as NavIC (Navigation with Indian Constellation), is a regional navigation system that will provide precise positioning and timing services within India and 1500 km around the Indian borders. Planned after the Kargil War (1999) to lessen the reliance on foreign systems such as GPS, NavIC guarantees the full Indian ownership of its space, ground, and user segments. NavIC is 3rd Generation Partnership Project (3GPP) certified, and it is meant to be used in civilian strategic applications.

NavIC Architecture

The space segment comprises a seven-satellite constellation: three in geostationary orbit (32.5°E, 83°E, 131.5°E) and four in geosynchronous orbit (55°E, 111.75°E). These satellites, weighing approximately 1425 kg (first generation) or 2232 kg (second generation, e.g., NVS 01), are equipped with navigation payloads operating on L5 (1176.45 MHz) and S-band (2492.028 MHz) frequencies, rubidium atomic clocks, and C-band transponders. The newer NVS series introduces the L1 frequency (1575.42 MHz) to ensure better interoperability with global systems. However, due to atomic clock failures and launch delays, only five satellites (IRNSS 1B, 1C, 1F, 1I, and NVS 01) remain fully operational as of February 2025.

The ground segment of India’s navigation system is managed by the ISRO Navigation Centre (INC) in Byalalu, Karnataka, and comprises several critical components: IRNSS Range Integrity Monitoring Stations (IRIMS) ensure signal accuracy, while the IRNSS Network Timing Centre (IRNWT) delivers time precision within 2 nanoseconds (2 sigma) relative to UTC. Orbit determination is supported by IRNSS CDMA Ranging Stations (IRCDR) and laser ranging facilities, with satellite operations conducted through the IRNSS Spacecraft Control Facility (IRSCF). Secure data transmission is enabled by the IRNSS Data Communication Network (IRDCN) using terrestrial VSAT links. Additionally, international collaborations, with a ground station operational in Japan (via JAXA), ongoing discussions with France’s CNES, and potential installations in Australia’s Cocos Islands, augment signal triangulation and global reach.

NavIC was born out of India’s need for strategic independence after GPS denial during the Kargil War.

The user segment is compatible with single-frequency (L5 or S-band) and dual-frequency (L5 and S-band) receivers and newer devices are also L1 compatible to enhance global interoperability. It offers a Standard Positioning Service (SPS) to civilian users with <20 m accuracy, and a Restricted Service (RS) to authorised users with <5 m accuracy, using Binary Offset Carrier (BOC) modulation to provide greater signal security. The NavIC-enabled receivers are also combined with other GNSS such as GPS, GLONASS, Galileo, and BeiDou in order to provide reliable and accurate navigation.

The dual frequency L5 and S-band NavIC signals have different benefits: they provide direct ionospheric correction, which is not available in the model-based GPS system, with 5-10 m accuracy in the SPS and sub-meter in the RS. Having a regional coverage, NavIC signals are received at high elevation angle (90), which means enhanced penetration in forest, urban canyons, and hilly terrain. It also has a special messaging feature to provide area-specific disaster messages, and interoperability with the L5 and newly added L1 frequencies that are globally recognized, increasing compatibility with consumer GNSS devices.

Integration with India’s Defense Systems

The strategic importance of NavIC is that it can offer secure and independent navigation timing services that are essential to the defense forces in India. It was developed due to the US refusal to grant access to the GPS in the Kargil War, which emphasized the need to have sovereignty in navigation.

NavIC is of strategic importance because it provides independent and uninterrupted navigation services in times of conflict, unlike GPS, GLONASS, or BeiDou, which are controlled by foreign powers and can degrade access to civilians. Its Restricted Service (RS) provides sub-5-meter accuracy that is needed in precision strikes and operations in contested environments. Also, the signal integrity is enhanced by encrypted RS signals with BOC(5,2) modulation and planned long-code support to overcome the risk of spoofing and unauthorized access.

NavIC is central to the Indian defense system as it directs precision weapons such as BrahMos missiles and UAVs, and troop and vehicle navigation in challenging terrains along the LoC and LAC. It is integrated with RISAT and Cartosat satellites to give real-time geolocation of reconnaissance and border surveillance. It facilitates network-centric warfare by coordinating the secure communications with GSAT-6 and GSAT-7 satellites, which allows the coordination of operations of all military forces. NavIC, acknowledged by the IMO as WWRNS, improves the naval and submarine navigation, maritime surveillance, and coastal safety using transceivers on fishing vessels. It has a timing accuracy of 2 ns that helps in radar, missile protection, and command-control synchronization, and it does not rely on foreign systems.

NavIC has been fortified in the latest developments in terms of defense integration. A 2020 partnership with Qualcomm allowed NavIC compatibility in Snapdragon chipsets, and L1 signal compatibility on certain platforms by December 2023, and military grade mobile receivers and commercial implementation are expected in 2025. After failures of European rubidium clocks, the Space Applications Centre of ISRO made indigenous atomic clocks, which were first used in NVS 01, improving the reliability of the system. ISRO is also working on long code support for RS signals in order to enhance security against intrusion. Also, DRDO collaborates with ISRO to modify NavIC to guide its missiles, encrypted communications, and general defense hardware applications.

Future Expansion Plans: NavIC 2.0 Global Aspirations

ISRO is developing NavIC 2.0, which will help in increasing coverage and accuracy and rival world GNSS systems. These include new satellites, new frequencies, and international collaborations.

The navigation space segment of India is currently limited, with only five of the eleven satellites launched fully operational because of the failure of atomic clocks and delays, such as the failure of the NVS 02 engine in January 2025. To overcome this, ISRO is launching the second-generation NVS series (NVS 01-05), which will have indigenous atomic clocks and L1 signal capability. NVS 03-05 will be launched by 2026 and is expected to have a 12-year service life. Looking ahead, the Global Indian Navigation System (GINS) envisions a 26-satellite constellation by 2035, including 12 MEO satellites at 24,000 km to provide global coverage, with spectrum filings completed in 2013. Under India’s space reforms, NSIL and private industry partners will support satellite production, bolstering capacity and self-reliance.

NavIC’s dual-band navigation capability leverages the L5 band (1176.45 MHz), a globally recognized frequency offering strong, interference-resistant signals interoperable with GPS, Galileo, and BeiDou. The uniquely Indian S-band (2492.028 MHz) addresses ionospheric distortion common in tropical regions, enhancing positional accuracy; together, dual-band L5/S-band receivers enable real-time ionospheric correction superior to single-frequency GPS. The NVS series adds L1 (1575.42 MHz), facilitating integration into low-power devices like wearables and military gear, using patented high-performance spreading codes developed by ISRO and IISc in 2021. With a fully functional ground segment, SPS accuracy is targeted at 5 meters, while RS aims for sub-meter precision.

Enhancements to NavIC’s ground segment include international ground stations in Japan (operational), France (under discussion), and Australia’s Cocos Islands (planned), which will improve signal triangulation and accuracy. By 2025, a high-speed encrypted network will link strategic control centers and timing facilities, strengthening defense readiness. On the commercial front, Antrix is collaborating with industry partners to develop NavIC-based hardware, including defense-grade receivers, while mandatory integration of NavIC for vehicle tracking by the Ministry of Road Transport is accelerating nationwide adoption.

India’s strategic diplomatic objectives for NavIC center on expanding global influence and regional leadership. The planned Global Indian Navigation System (GINS) aspires to rival GPS, GLONASS, Galileo, and BeiDou, establishing India as a major space power. Regionally, NavIC’s coverage of SAARC nations supports data-sharing agreements and fosters diplomatic goodwill. Strategically, India aims to achieve full military navigation autonomy by 2028, eliminating reliance on foreign systems. On the civilian front, collaborations with Qualcomm, MapmyIndia, and device manufacturers aim to mainstream NavIC across smartphones, vehicles, and IoT platforms, with full compatibility expected by 2025.

Challenges Recent Setbacks

NavIC has a number of issues and recent setbacks affecting its performance and growth. Satellite failures in the IRNSS 1A, 1C, 1D, 1E, and 1G rubidium clocks and the engine failure of NVS 02 in 2025 have decreased the redundancy of the constellation, but indigenous clock development has enhanced reliability. There are just five active satellites, which limits the robustness of the system, and this necessitates faster NVS launches. The integration of mobile has not been on schedule as initially set in 2023; it is projected that full compatibility will be achieved in 2025 because of hurdles in the industry adaptation. The switch to GINS requires massive investment, international relations to lease orbital slots, and the development of international cooperation globally.

The recent successes point to the main opportunities for the development of NavIC. The Atmanirbhar Bharat initiative is strengthened by the successful development of indigenous rubidium clocks and L1 codes, which reduces foreign dependency developed by ISRO. Defence integration augments the strategic capabilities of India in the Indo-Pacific region, whereas commercial requirements, including the mandatory application of NavIC in vehicle tracking, collaboration with Qualcomm and MapmyIndia, suggest high chances of mass market penetration.

ISRO plans a 26-satellite NavIC 2.0 constellation by 2035 to ensure global coverage and GNSS competitiveness.

Recent developments in the development of NavIC are the successful launch of NVS 01 in May 2023, which will provide L1 signals and indigenous atomic clocks, and its operational deployment on January 30, 2025. December 2022 update of Qualcomm chipsets allowed supporting L1 and expanded civilian and military use. Also, the adoption of NavIC by the International Maritime Organization (IMO) has increased its profile in the international maritime navigation and safety system.

The NavIC is a strategic success of ISRO, as it guarantees the sovereignty of navigation that can strengthen India in terms of its defense. Its compatibility with military systems, including missile guidance to secure communications, covers the major weaknesses that were highlighted in the Kargil War. The dual-band L5 S band functionalities, along with the additional L1 frequency, render NavIC an accurate, interoperable substitute to GPS. With mishaps such as clock failures and recent launch problems, the ISRO NavIC 2.0, with a 26-satellite global system by 2030, ground stations internationally, and involvement of the private sector, will put India on the world map. NavIC may soon come to dominate the defense navigation in India with commercial applications too, making ISRO a global space powerhouse in the innovation space.

The Indian Regional Navigation Satellite System (IRNSS) or NavIC (Navigation with Indian Constellation) is mostly aimed at the provision of precise positioning, navigation, and timing (PNT) services in the region of India, a 1500 km radius around the country, including Pakistan. Although the main focus of NavIC is to provide India with strategic independence in navigation, the deployment of the system in defense has caused uneasiness and speculation that it can be used to spy, especially in India-Pakistan relations. Following is the breakdown of the Indian use of the NavIC in defense, such as possible surveillance of Pakistan, as per the available information and recent developments. It is important to note that there is little direct evidence that NavIC has been used specifically to spy on Pakistan in real time; much of the discussion is based on strategic implications of reported capabilities.

NavIC’s Capabilities Relevant to Defense Surveillance

NavIC’s architecture services make it a critical asset for India’s defense forces, particularly in monitoring operations along its borders, including with Pakistan.

Key features include:

• Restricted Service (RS): NavIC provides an encrypted RS for authorized users, primarily the Indian Armed Forces, offering sub-5-meter accuracy using dual-frequency L5 (1176.45 MHz) S band (2492.028 MHz) signals with Binary Offset Carrier (BOC) modulation.
  This high-precision service supports military navigation, targeting geolocation essential for surveillance and reconnaissance.
• Regional Coverage: NavIC covers India with a 1500 km radius encompassing Pakistan entirely. An extended service area (30°S to 50°N, 30°E to 130°E) allows partial visibility of NavIC signals in parts of Pakistan, though with reduced accuracy.
  This regional focus ensures robust signal availability along the Line of Control (LoC) international border with Pakistan.
• Integration with Earth Observation Satellites: NavIC works in tandem with ISRO’s imaging satellites like RISAT (radar imaging), Cartosat (optical imaging), which provide high-resolution imagery for border surveillance. NavIC’s precise geolocation enhances the accuracy of these images, aiding in tracking movements or infrastructure development.
• Timing Synchronization: NavIC’s 2 ns timing accuracy synchronizes defense systems, including radar, missile defense communication networks, enabling coordinated surveillance operations. The indigenous IRNSS Network Timing System, developed with Accord Software, reduces reliance on US-provided timing, ensuring resilience during conflicts.
• Messaging Interface: NavIC’s ability to send alerts to specific geographic areas supports real-time communication for defense operations, potentially relaying intelligence or warnings along border areas.

Strategic Context: India-Pakistan Tensions, NavIC’s Role

The genesis of NavIC traces back to the Kargil War (1999) when the US denied India access to GPS for military operations against Pakistan, exposing India’s vulnerability. NavIC addresses this by providing sovereign control over navigation, critical for monitoring Pakistan, given the country’s history of conflict and ongoing border disputes. While no official Indian source explicitly confirms NavIC’s use for real-time surveillance of Pakistan, its capabilities reported defense applications suggest the following uses:

• Border Surveillance Intrusion Detection: NavIC’s high-precision RS signals enable accurate geolocation of Indian assets along the LoC border, facilitating monitoring of Pakistani troop movements or incursions. Integrated with RISAT’s all-weather radar imaging, NavIC can geolocate targets in Pakistan-administered Kashmir or border areas even in adverse conditions.
• Missile Drone Guidance: NavIC guides precision-guided munitions (e.g., BrahMos missiles), drones which can be used for both offensive strikes and reconnaissance missions over Pakistani territory. Posts on X claim NavIC was used for precision strikes during a hypothetical ‘Operation Sindoor’, achieving 2-meter accuracy, though no official evidence supports this operation. This reflects sentiment about NavIC’s potential for targeted operations.
• Jamming Counter Surveillance: Recent reports indicate India deployed high-frequency jamming systems along its western border to disrupt GNSS signals (GPS, GLONASS, BeiDou) used by Pakistani military aircraft, degrading their navigation strike capabilities.
  NavIC’s independent signals ensure India’s assets remain unaffected by such jamming, providing a strategic advantage for surveillance operations. This suggests NavIC’s role in maintaining situational awareness while disrupting Pakistan’s reliance on foreign GNSS.
• Intelligence Gathering: NavIC’s integration with GSAT 6 and GSAT 7 military communication satellites supports secure data transfer for intelligence gathered along the border. Combined with Cartosat imagery, NavIC can map Pakistani military infrastructure, such as bases or fortifications, with high accuracy.
• Maritime Surveillance: NavIC’s recognition by the International Maritime Organization (IMO) as part of the World Wide Radio Navigation System (WWRNS) enhances India’s naval capabilities in the Arabian Sea, where Pakistan operates. Indian naval vessels’ submarines can use NavIC for precise navigation and tracking of Pakistani maritime assets, including in contested waters.

Recent Developments (2024-2025)

Between 2024 and 2025, NavIC has undergone critical technological upgrades, enhancing its surveillance capabilities, though challenges remain. The NVS satellite series, beginning with NVS 01 (May 2023), introduced the L1 frequency and indigenous atomic clocks to resolve previous failures seen in IRNSS 1A, 1D, 1E, and 1G; while NVS 02 experienced a partial engine failure in January 2025, NVS 03–05 are slated for launch by 2026 to complete the constellation. L1 signal integration improves compatibility with military receivers, enhancing real-time tracking.

The IRNSS Network Timing System, co-developed with Accord Software, will replace U.S.-provided synchronization by 2025, securing Indian defense communications. Qualcomm’s chipset support for L1 (announced December 2023) brings field-grade surveillance capabilities to mobile platforms, while ISRO’s ongoing development of long code signals for RS boosts encryption, vital for secure operations near the LoC. International ground stations, especially in Japan, France, and the Cocos Islands, are enhancing triangulation accuracy.

However, key limitations persist. With only five operational satellites as of February 2025 (IRNSS 1B, 1C, 1F, 1I, NVS 01), NavIC’s constellation lacks full redundancy, affecting surveillance continuity. While its primary service zone covers Pakistan, accuracy diminishes in the extended area, curtailing deep surveillance. Pakistan’s reliance on China’s BeiDou system, supported by a ground station in Karachi, reduces its dependency on GPS and may counterbalance NavIC’s strategic edge.

Moreover, the emergence of tactical nuclear weapons and missiles in Pakistan is an indicator that the country is trying to eliminate the Indian ISR (Intelligence, Surveillance, Reconnaissance) advantage. It is worth mentioning that the use of NavIC in operations such as the so-called Operation Sindoor is not supported by any verifiable evidence, and is based mostly on the accounts presented in social media; official accounts restrict themselves to the generic defense utility, without any specific reference to the surveillance operations.

Pakistan’s Perspective Concerns

To Pakistan, NavIC is considered a strategic tool towards India gaining military superiority, especially in surveillance, reconnaissance, and in the guidance of missiles. An early concern on Defence.pk (2016) was that NavIC will give India real-time battlefield awareness, which can greatly mitigate operational risks. It also indicated the dismal budgetary disparity; ISRO had a budget of ~$1 billion compared to ~$30.6 million of SUPARCO, which showed the low ability of Pakistan to develop a similar indigenous system. More recently, X (formerly Twitter) posts have heightened concerns that India’s GNSS jamming activities could indirectly support the operational superiority of NavIC, and contribute to the regional space-based ISR asymmetries.

Future Prospects: NavIC 2.0 Surveillance Implications

India has a plan to launch NavIC 2.0 based on the Global Indian Navigation System (GINS), where a constellation of 26 satellites (12 satellites in MEO) is expected by 2035, with global coverage and better accuracy in comparison to Pakistan. Improved SPS and RS accuracy of 5 meters and sub-meter, respectively, will facilitate high-fidelity surveillance, even in contested areas. The use of drones in ISR will most likely increase as receiver technologies improve with the help of NSIL and the private industries. Moreover, sharing of the data with the SAARC countries (not including Pakistan) would strengthen the regional surveillance frameworks and diplomatically isolate Pakistan. Cumulatively, these trajectories place NavIC 2.0 as an instrument of regional strategic advantage as well as global GNSS competitiveness.

Conclusion

India is relying on NavIC as a part of its defense policy, integrating its high-precision RS signals regional coverage with imaging communication satellites to improve border surveillance and missile guidance situational awareness along the Pakistan frontier. Although there is no direct evidence that NavIC is being used to conduct real-time surveillance over Pakistan, its capabilities, along with the reported jamming of foreign GNSS signals, indicate a strategic advantage of being able to monitor the activities of Pakistani military forces.

Although unproven, NavIC’s integration with RISAT and Cartosat raises concerns about potential surveillance over Pakistan.

New initiatives like native atomic clocks and L1 signalling support the plans of a worldwide constellation that enhances the capability of NavIC in both defense and surveillance uses. Nevertheless, problems such as the small number of satellites and the fact that Pakistan is using BeiDou moderate its impact at the moment. The capability of India to monitor Pakistan will probably increase as NavIC 2.0 develops its strategic position in a turbulent region.