63-535: 1B / 1C / 1D / 1F / 1I (Operational) 1A / 1E / 1G (Clock failure, short-message services only) 01 (Operational) The Indian Regional Navigation Satellite System ( IRNSS ), with an operational name of NavIC (acronym for Navigation with Indian Constellation ; also, nāvik 'sailor' or 'navigator' in Indian languages), is an autonomous regional satellite navigation system that provides accurate real-time positioning and timing services. It covers India and
126-408: A boost. A launch site should have water or deserts to the east, so any failed rockets do not fall on a populated area. Most launch vehicles place geosynchronous satellites directly into a geosynchronous transfer orbit (GTO), an elliptical orbit with an apogee at GSO height and a low perigee . On-board satellite propulsion is then used to raise the perigee, circularise and reach GSO. Once in
189-481: A higher graveyard orbit . It is not feasible to deorbit geosynchronous satellites, for to do so would take far more fuel than would be used by slightly elevating the orbit; and atmospheric drag is negligible, giving GSOs lifetimes of thousands of years. The retirement process is becoming increasingly regulated and satellites must have a 90% chance of moving over 200 km above the geostationary belt at end of life. Space debris in geosynchronous orbits typically has
252-415: A low-frequency signal travels through atmosphere, its velocity changes due to atmospheric disturbances. GPS depends on an atmospheric model to assess frequency error, and it has to update this model from time to time to assess the exact error. In NavIC, the actual delay is assessed by measuring the difference in delay of the two frequencies (S and L bands). Therefore, NavIC is not dependent on any model to find
315-618: A lower collision speed than at LEO since most GSO satellites orbit in the same plane, altitude and speed; however, the presence of satellites in eccentric orbits allows for collisions at up to 4 km/s. Although a collision is comparatively unlikely, GSO satellites have a limited ability to avoid any debris. Debris less than 10 cm in diameter cannot be seen from the Earth, making it difficult to assess their prevalence. Despite efforts to reduce risk, spacecraft collisions have occurred. The European Space Agency telecom satellite Olympus-1
378-438: A pancake-shaped waveform. In August 1961, they were contracted to begin building the working satellite. They lost Syncom 1 to electronics failure, but Syncom 2 was successfully placed into a geosynchronous orbit in 1963. Although its inclined orbit still required moving antennas, it was able to relay TV transmissions, and allowed for US President John F. Kennedy to phone Nigerian prime minister Abubakar Tafawa Balewa from
441-499: A phased array antenna to maintain required coverage and signal strength. The satellites would weigh approximately 1,330 kg (2,930 lb) and their solar panels generate 1,400 W. A messaging interface is embedded in the NavIC system. This feature allows the command center to send warnings to a specific geographic area. For example, fishermen using the system can be warned about a cyclone. The Standard Positioning Service system
504-406: A region extending 1,500 km (930 mi) around it, with plans for further extension up to 3,000 km (1,900 mi). An extended service area lies between the primary service area and a rectangle area enclosed by the 30th parallel south to the 50th parallel north and the 30th meridian east to the 130th meridian east , 1,500–6,000 km (930–3,730 mi) beyond borders where some of
567-497: A regional one targeted towards South Asia. The satellite will provide navigation, tracking and mapping services. IRNSS-1B satellite has two payloads: a navigation payload and CDMA ranging payload in addition with a laser retro-reflector. The payload generates navigation signals at L5 and S-band. The design of the payload makes the IRNSS system interoperable and compatible with Global Positioning System (GPS) and Galileo. The satellite
630-558: A ship on August 23, 1963. Today there are hundreds of geosynchronous satellites providing remote sensing , navigation and communications. Although most populated land locations on the planet now have terrestrial communications facilities ( microwave , fiber-optic ), which often have latency and bandwidth advantages, and telephone access covering 96% of the population and internet access 90% as of 2018, some rural and remote areas in developed countries are still reliant on satellite communications. A geostationary equatorial orbit (GEO)
693-422: A viable geostationary orbit, spacecraft can change their longitudinal position by adjusting their semi-major axis such that the new period is shorter or longer than a sidereal day, in order to effect an apparent "drift" Eastward or Westward, respectively. Once at the desired longitude, the spacecraft's period is restored to geosynchronous. A statite is a hypothetical satellite that uses radiation pressure from
SECTION 10
#1732776350332756-667: Is a frozen orbit , which reduces the need for stationkeeping . At least two satellites are needed to provide continuous coverage over an area. It was used by the Sirius XM Satellite Radio to improve signal strength in the northern US and Canada. The Quasi-Zenith Satellite System (QZSS) is a four-satellite system that operates in a geosynchronous orbit at an inclination of 42° and a 0.075 eccentricity. Each satellite dwells over Japan , allowing signals to reach receivers in urban canyons then passes quickly over Australia. Geosynchronous satellites are launched to
819-491: Is a circular geosynchronous orbit in the plane of the Earth's equator with a radius of approximately 42,164 km (26,199 mi) (measured from the center of the Earth). A satellite in such an orbit is at an altitude of approximately 35,786 km (22,236 mi) above mean sea level. It maintains the same position relative to the Earth's surface. If one could see a satellite in geostationary orbit, it would appear to hover at
882-596: Is in talks with the Australian Space Agency . NavIC signals will consist of a Standard Positioning Service and a Restricted Service. Both will be carried on L5 (1176.45 MHz) and S band (2492.028 MHz). The SPS signal will be modulated by a 1 MHz BPSK signal. The Restricted Service will use BOC(5,2) . The navigation signals themselves would be transmitted in the L5 (1176.45 MHz) & S band (2492.028 MHz) frequencies and broadcast through
945-557: Is intended to provide an absolute position accuracy of about 5 to 10 metres throughout the Indian landmass and an accuracy of about 20 metres (66 ft) in the Indian Ocean as well as a region extending approximately 1,500 km (930 mi) around India. GPS, for comparison, has a position accuracy of 5 m under ideal conditions. However, unlike GPS, which is dependent only on L-band, NavIC has dual frequencies (S and L bands). When
1008-676: Is not guaranteed in hostile situations, as happened to the Indian military in 1999 when the United States denied an Indian request for Global Positioning System (GPS) data for the Kargil region , which would have provided vital information. The Indian government approved the project in May 2006. As part of the project, the Indian Space Research Organisation (ISRO) opened a new satellite navigation centre within
1071-633: Is planned to be available for civilian use in mobile devices, after Qualcomm and ISRO signed an agreement. To increase compatibility with existing hardware, ISRO will add L1 band support. For strategic application, Long Code support is also coming. On December 7, 2023, Qualcomm revealed that select chipset platforms will enable NavIC L1 signals. The Qualcomm location suite, supports up to seven satellite constellations simultaneously and allows for faster Time to First Fix (TTFF) position acquisition for enhanced location-based services . It also makes use of all of NavIC's L1 and L5 signals for precise positioning. In
1134-724: Is powered by two solar arrays, which generate power up to 1,660 watts, and has a life-time of ten years. The 1,432 kg satellite was launched on 4 April 2014 at 11:44 UTC (17:14 IST ) aboard the PSLV-C24 rocket from Satish Dhawan Space Centre , Sriharikota . Geosynchronous orbit A geosynchronous orbit (sometimes abbreviated GSO ) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day ). The synchronization of rotation and orbital period means that, for an observer on Earth's surface, an object in geosynchronous orbit returns to exactly
1197-602: Is supposed to have a constellation of 24 satellites, positioned 24,000 km (14,913 mi) above Earth. As of 2013, the statutory filing for frequency spectrum of GINS satellite orbits in international space, has been completed. As per new 2021 draft policy, ISRO and Department of Space (DoS) is working on expanding the coverage of NavIC from regional to global that will be independent of other such system currently operational namely GPS , GLONASS , BeiDou and Galileo while remain interoperable and free for global public use. ISRO has proposed to Government of India to expand
1260-492: Is the geostationary orbit (often abbreviated GEO ), which is a circular geosynchronous orbit in Earth's equatorial plane with both inclination and eccentricity equal to 0. A satellite in a geostationary orbit remains in the same position in the sky to observers on the surface. Communications satellites are often given geostationary or close-to-geostationary orbits, so that the satellite antennas that communicate with them do not have to move but can be pointed permanently at
1323-463: Is the minimum number required for service to remain operational. In order to reduce the dependency on imported frequency standards ISRO's Space Applications Centre (SAC), Ahmedabad had been working on domestically designed and developed Rubidium based atomic clocks . To overcome the clock failures on first generation navigation satellites and its subsequent impact on NavIC's position, navigation, and timing services, these new clocks would supplement
SECTION 20
#17327763503321386-566: Is the second out of seven in the Indian Regional Navigation Satellite System (IRNSS) series of satellites after IRNSS-1A . The IRNSS constellation of satellites is slated to be launched to provide navigational services to the region. It was placed in geosynchronous orbit on 4 April 2014. The satellite will help augmenting the satellite based navigation system of India which is currently under development. The navigational system so developed will be
1449-631: The Indian Armed Forces . They will be equipped with L1 band along with the L5 and S band. The system will provide an accuracy of 10 m (33 ft) within India, 20 m (66 ft) for the area surrounding India by 1,500 km (930 mi). Study and analysis for the Global Indian Navigation System (GINS) was initiated as part of the technology and policy initiatives in the 12th FYP (2012–17). The system
1512-720: The Indian Ocean . Missile targeting could be an important military application for the constellation. The total cost of the project was expected to be ₹ 14.2 billion (US$ 170 million), with the cost of the ground segment being ₹ 3 billion (US$ 36 million), each satellite costing ₹ 1.5 billion (US$ 18 million) and the PSLV-XL version rocket costing around ₹ 1.3 billion (US$ 16 million). The planned seven rockets would have involved an outlay of around ₹ 9.1 billion (US$ 109 million). The necessity for two replacement satellites, and PSLV-XL launches, has altered
1575-597: The L1 band in the navigation payload and will use Indian Rubidium Atomic Frequency Standard (iRAFS.) This introduction of the new L1 band will help facilitate NavIC proliferation in wearable smart and IoT devices featuring a low power navigation system. NVS-01 is a replacement for IRNSS-1G satellite and was launched on GSLV in 2023. ISRO has plans for a total of 7 NVS series satellites (including already launched NVS-1) for civilian navigation requirements. The IRNSS network is, as of November 2024, confined to strategic use by
1638-538: The United States Congress consented to designate NaVIC as one of their allied navigational satellite systems along with Galileo (Europe) and QZSS (Japan). The approval was as a part of National Defense Authorization Act 2020 . The proposal was put forward by United States Secretary of Defense in consultation with Director of National Intelligence . The IRNSS series of satellite utilises rubidium atomic clocks sourced from Israel. In 2017, it
1701-555: The Earth's gravitational field, and the gravitational effect of the Moon and Sun , and thrusters are used to maintain the orbit in a process known as station-keeping . Eventually, without the use of thrusters, the orbit will become inclined, oscillating between 0° and 15° every 55 years. At the end of the satellite's lifetime, when fuel approaches depletion, satellite operators may decide to omit these expensive manoeuvres to correct inclination and only control eccentricity. This prolongs
1764-470: The IRNSS constellation. The ground segment comprises: The IRSCF is operational at Master Control Facility (MCF), Hassan and Bhopal. The MCF uplinks navigation data and is used for tracking, telemetry and command functions. Seven 7.2-metre (24 ft) FCA and two 11-metre (36 ft) FMA of IRSCF are currently operational for LEOP and on-orbit phases of IRNSS satellites. The INC established at Byalalu performs remote operations and data collection with all
1827-624: The IRNSS satellites. The IRNWT has been established and is providing IRNSS system time with an accuracy of 2 ns (2.0 × 10 s ) (2 sigma) with respect to UTC . Laser ranging is being carried out with the support of ILRS stations around the world. Navigation software is operational at INC since 1 Aug 2013. All the navigation parameters, such as satellite ephemeris , clock corrections, integrity parameters, and secondary parameters, such as iono-delay corrections, time offsets with respect to UTC and other GNSSes , almanac , text message, and earth orientation parameters, are generated and uploaded to
1890-461: The NavIC satellites are visible but the position is not always computable with assured accuracy. The system currently consists of a constellation of eight satellites, with two additional satellites on ground as stand-by. The constellation is in orbit as of 2018. NavIC will provide two levels of service, the "standard positioning service", which will be open for civilian use, and a "restricted service" (an encrypted one) for authorised users (including
1953-465: The Sun against a solar sail to modify its orbit. It would hold its location over the dark side of the Earth at a latitude of approximately 30 degrees. It would return to the same spot in the sky every 24 hours from an Earth-based viewer's perspective, so be functionally similar to a geosynchronous orbit. A further form of geosynchronous orbit is the theoretical space elevator . If a mass orbiting above
Indian Regional Navigation Satellite System - Misplaced Pages Continue
2016-544: The Technology Development Fund scheme, has commissioned Accord Software and Systems, to build a tailored and flexible IRNSS Network Timing system domestically. Using NavIC data, the receiver chip will obtain and distribute Indian time for navigation. India currently depends on the US for this service. In 2020, Qualcomm launched four Snapdragon 4G chipsets and one 5G chipset with support for NavIC. NavIC
2079-659: The beginning of 13th FYP (2018–23) in geosynchronous orbit of 42° inclination. Also, the development of space-qualified Indian made atomic clocks was initiated, along with a study and development initiative for an all optical atomic clock (ultra stable for IRNSS and deep space communication ). The NavIC Signal in Space ICD was released for evaluation in September 2014. From 1 April 2019, use of AIS 140 compliant NavIC-based vehicle tracking systems were made compulsory for all commercial vehicles in India. In December 2019,
2142-597: The campus of ISRO Deep Space Network (DSN) at Byalalu , in Karnataka on 28 May 2013. A network of 21 ranging stations located across the country will provide data for the orbital determination of the satellites and monitoring of the navigation signal. A goal of complete Indian control has been stated, with the space segment, ground segment and user receivers all being built in India. Its location in low latitudes facilitates coverage with low- inclination satellites. Three satellites will be in geostationary orbit over
2205-505: The collection of artificial satellites in this orbit is known as the Clarke Belt. In technical terminology, the geosynchronous orbits are often referred to as geostationary if they are roughly over the equator, but the terms are used somewhat interchangeably. Specifically, geosynchronous Earth orbit ( GEO ) may be a synonym for geosynchronous equatorial orbit , or geostationary Earth orbit . The first geosynchronous satellite
2268-528: The concept in a 1945 paper entitled Extra-Terrestrial Relays – Can Rocket Stations Give Worldwide Radio Coverage? , published in Wireless World magazine. Clarke acknowledged the connection in his introduction to The Complete Venus Equilateral . The orbit, which Clarke first described as useful for broadcast and relay communications satellites, is sometimes called the Clarke Orbit. Similarly,
2331-415: The concept was seen as impractical, so Hughes often withheld funds and support. By 1961, Rosen and his team had produced a cylindrical prototype with a diameter of 76 centimetres (30 in), height of 38 centimetres (15 in), weighing 11.3 kilograms (25 lb); it was light, and small, enough to be placed into orbit by then-available rocketry, was spin stabilised and used dipole antennas producing
2394-472: The constellation for global coverage by initially placing twelve satellites in Medium Earth Orbit (MEO). The constellation consists of 7 active satellites. Three of the seven satellites in constellation are located in geostationary orbit (GEO) and four are in inclined geosynchronous orbit (IGSO). All satellites launched or proposed for the system are as follows: IRNSS-1B IRNSS-1B
2457-402: The east into a prograde orbit that matches the rotation rate of the equator. The smallest inclination that a satellite can be launched into is that of the launch site's latitude, so launching the satellite from close to the equator limits the amount of inclination change needed later. Additionally, launching from close to the equator allows the speed of the Earth's rotation to give the satellite
2520-565: The fixed location in the sky where the satellite appears. In 1929, Herman Potočnik described both geosynchronous orbits in general and the special case of the geostationary Earth orbit in particular as useful orbits for space stations . The first appearance of a geosynchronous orbit in popular literature was in October 1942, in the first Venus Equilateral story by George O. Smith , but Smith did not go into details. British science fiction author Arthur C. Clarke popularised and expanded
2583-489: The following properties: All geosynchronous orbits have an orbital period equal to exactly one sidereal day. This means that the satellite will return to the same point above the Earth's surface every (sidereal) day, regardless of other orbital properties. This orbital period, T, is directly related to the semi-major axis of the orbit through the formula: where: A geosynchronous orbit can have any inclination. Satellites commonly have an inclination of zero, ensuring that
Indian Regional Navigation Satellite System - Misplaced Pages Continue
2646-405: The frequency error and can be more accurate than GPS. ISRO will be launching five next generation satellite featuring new payloads and extended lifespan of 12 years. Five new satellites viz. NVS-01, NVS-02, NVS-03, NVS-04 and NVS-05 will supplement and augment the current constellation of satellites. The new satellites will feature the L5 and S band and introduces a new interoperable civil signal in
2709-561: The geostationary belt is tethered to the earth’s surface, and the mass is accelerated to maintain an orbital period equal to one sidereal day, then since the orbit now requires more downward force than is supplied by gravity alone. The tether will become tensioned by the extra centripetal force required, and this tension force is available to hoist objects up the tether structure. Geosynchronous satellites require some station-keeping in order to remain in position, and once they run out of thruster fuel and are no longer useful they are moved into
2772-488: The ground stations. The ISRO Navigation Centers (INC) are operational at Byalalu, Bengaluru and Lucknow. INC1 (Byalalu) and INC2 (Lucknow) together provide seamless operations with redundancy. 16 IRIMS are currently operational and are supporting IRNSS operations few more are planned in Brunei, Indonesia, Australia, Russia, France and Japan. CDMA ranging is being carried out by the four IRCDR stations on regular basis for all
2835-557: The imported atomic clocks in next generation of navigation satellites. On 5 July 2017, ISRO and Israel Space Agency (ISA) signed an Memorandum of Understanding to collaborate on space qualifying a Rubidium Standard based on AccuBeat model AR133A and to test it on an ISRO satellite. The clocks are utilised by the NVS series of satellites. In accordance with the range requirements for NavIC for both military and commercial applications, Defence Research and Development Organisation , through
2898-495: The life-time of the satellite as it consumes less fuel over time, but the satellite can then only be used by ground antennas capable of following the N-S movement. Geostationary satellites will also tend to drift around one of two stable longitudes of 75° and 255° without station keeping. Many objects in geosynchronous orbits have eccentric and/or inclined orbits. Eccentricity makes the orbit elliptical and appear to oscillate E-W in
2961-403: The military). NavIC-based trackers are compulsory on commercial vehicles in India and some consumer mobile phones with support for it have been available since the first half of 2020. There are plans to expand the NavIC system by increasing its constellation size from 7 to 11. The system was developed partly because access to foreign government-controlled global navigation satellite systems
3024-450: The orbit remains over the equator at all times, making it stationary with respect to latitude from the point of view of a ground observer (and in the ECEF reference frame). Another popular inclinations is 63.4° for a Tundra orbit, which ensures that the orbit's argument of perigee does not change over time. In the special case of a geostationary orbit, the ground track of a satellite
3087-469: The original budget, with the Comptroller and Auditor General of India reporting costs (as of March 2017) of ₹ 22.46 billion (US$ 269 million). India's Department of Space in their 12th Five Year Plan (FYP) (2012–17) stated increasing the number of satellites in the constellation from 7 to 11 to extend coverage. These additional four satellites will be made during 12th FYP and will be launched in
3150-523: The program was delayed, and India also launched 3 new satellites to supplement this. Seven satellites with the prefix "IRNSS-1" will constitute the space segment of the IRNSS. IRNSS-1A , the first of the seven satellites, was launched on 1 July 2013. IRNSS-1B was launched on 4 April 2014 on-board PSLV-C24 rocket. The satellite has been placed in geosynchronous orbit . IRNSS-1C was launched on 16 October 2014, IRNSS-1D on 28 March 2015, IRNSS-1E on 20 January 2016, IRNSS-1F on 10 March 2016 and IRNSS-1G
3213-412: The same point in the sky, i.e., not exhibit diurnal motion , while the Sun, Moon, and stars would traverse the skies behind it. Such orbits are useful for telecommunications satellites . A perfectly stable geostationary orbit is an ideal that can only be approximated. In practice the satellite drifts out of this orbit because of perturbations such as the solar wind , radiation pressure , variations in
SECTION 50
#17327763503323276-413: The same position in the sky after a period of one sidereal day. Over the course of a day, the object's position in the sky may remain still or trace out a path, typically in a figure-8 form , whose precise characteristics depend on the orbit's inclination and eccentricity . A circular geosynchronous orbit has a constant altitude of 35,786 km (22,236 mi). A special case of geosynchronous orbit
3339-469: The second half of 2024, Qualcomm chipset platforms will add further support for the NavIC L1 signals, and in the first half of 2025, commercial products that support the NavIC L1 signals should be available for sale. In April 2010, it was reported that India plans to start launching satellites by the end of 2011, at a rate of one satellite every six months. This would have made NavIC functional by 2015. But
3402-415: The seven satellites are located in geostationary orbit (GEO) at longitudes 32.5° E, 83° E, and 131.5° E, approximately 36,000 km (22,000 mi) above Earth's surface. The remaining four satellites are in inclined geosynchronous orbit (GSO). Two of them cross the equator at 55° E and two at 111.75° E. The ground segment is responsible for the maintenance and operation of
3465-510: The sky from the viewpoint of a ground station, while inclination tilts the orbit compared to the equator and makes it appear to oscillate N-S from a groundstation. These effects combine to form an analemma (figure-8). Satellites in elliptical/eccentric orbits must be tracked by steerable ground stations . The Tundra orbit is an eccentric geosynchronous orbit, which allows the satellite to spend most of its time dwelling over one high latitude location. It sits at an inclination of 63.4°, which
3528-514: The spacecraft automatically. The IRDCN has established terrestrial and VSAT links between the ground stations. As of March 2021, ISRO and JAXA are performing calibration and validation experiments for NavIC ground reference station in Japan. ISRO is also under discussion with CNES for a NavIC ground reference station in France. ISRO is planning a NavIC ground station at Cocos (Keeling) Islands and
3591-403: The total number of failed clocks to five, in May 2018 a failure of a further 4 clocks was reported, taking the count to 9 of the 24 in orbit. As a precaution to extend the operational life of navigation satellite, ISRO is running only one rubidium atomic clock instead of two in the remaining satellites. As of May 2023 only four satellites are capable of providing navigation services which
3654-480: The two standby satellites, IRNSS-1H and IRNSS-1I in June 2017. The subsequent launch of IRNSS-1H, as a replacement for IRNSS-1A, was unsuccessful when PSLV-C39 mission failed on 31 August 2017. The second standby satellite, IRNSS-1I, was successfully placed into orbit on 12 April 2018. In July 2017, it was reported that two more clocks in the navigational system had also started showing signs of abnormality, thereby taking
3717-515: Was announced that all three SpectraTime supplied rubidium atomic clocks on board IRNSS-1A had failed, mirroring similar failures in the European Union's Galileo constellation. The first failure occurred in July 2016, followed soon after by the two other clocks on IRNSS-1A. This rendered the satellite non-functional and required replacement. ISRO reported it had replaced the atomic clocks in
3780-403: Was designed by Harold Rosen while he was working at Hughes Aircraft in 1959. Inspired by Sputnik 1 , he wanted to use a geostationary (geosynchronous equatorial) satellite to globalise communications. Telecommunications between the US and Europe was then possible between just 136 people at a time, and reliant on high frequency radios and an undersea cable . Conventional wisdom at the time
3843-401: Was launched on 28 April 2016. The eighth satellite, IRNSS-1H , which was meant to replace IRNSS-1A, failed to deploy on 31 August 2017 as the heat shields failed to separate from the 4th stage of the rocket. IRNSS-1I was launched on 12 April 2018 to replace it. The IRNSS system comprises a space segment and a support ground segment . The constellation consists of 7 satellites. Three of
SECTION 60
#17327763503323906-491: Was struck by a meteoroid on August 11, 1993, and eventually moved to a graveyard orbit , and in 2006 the Russian Express-AM11 communications satellite was struck by an unknown object and rendered inoperable, although its engineers had enough contact time with the satellite to send it into a graveyard orbit. In 2017 both AMC-9 and Telkom-1 broke apart from an unknown cause. A geosynchronous orbit has
3969-492: Was that it would require too much rocket power to place a satellite in a geosynchronous orbit and it would not survive long enough to justify the expense, so early efforts were put towards constellations of satellites in low or medium Earth orbit. The first of these were the passive Echo balloon satellites in 1960, followed by Telstar 1 in 1962. Although these projects had difficulties with signal strength and tracking that could be solved through geosynchronous satellites,
#331668