Indian Navigation Constellation (NAVIC) aka IRNSS

[Abhi9]

Interesting news:

Germany received signal from IRNSS 1A . I always though that scope of the signal will be more than 1500 Kms outside of india. so whole china is within reach with IRNSS guidance for Nirbhaya, Brahmos and future JDAM like weapons


Indian Regional Navigation Satellite Starts Signal Transmissions | idrw.org

ndian Regional Navigation Satellite Starts Signal Transmissions
Published July 27, 2013 | By admin
SOURCE: Richard B. Langley For GPS WORLD

Scientists from the German Aerospace Center's Institute of Communications and Navigation in Oberpfaffenhofen, Germany, have received signals from IRNSS-1A, the first satellite in the Indian Regional Navigation Satellite System.

Launched on July 1, 2013, the satellite reached its designated inclined geosynchronous orbit by July 18 with an inclination of 27 degrees and an equator crossing of 55 degrees east longitude. Indian Space Research Organisation (ISRO) chairperson Dr. K. Radhakrishnan announced on July 18 that testing of the satellite's navigation payload would begin within a week.

On July 23, the German Aerospace Center scientists pointed their 30-meter dish antenna at Weilheim towards the satellite and found that it was already transmitting a signal in the L5 frequency band.



Figure 1 shows the spectrum of the received signal. Centered at 1176.45 MHz, the signal has a single symmetrical main lobe and a number of side lobes characteristic of a spread-spectrum signal. The corresponding IQ constellation diagram is shown in Figure 2. The signal structure appears to be unlike those used by the GPS, GLONASS, Galileo, or BeiDou constellations. Further analysis will be required to sleuth the signal details as ISRO, so far, has not publicly released an IRNSS interface control document (ICD). ICDs characteristically describe a satellite system's signal structure in detail.

The German scientists caution that "this is a very early snapshot of the current signal transmission and probably both the signal power and the signal quality will change and possibly improve during the in-orbit-testing phase of the satellite's operation."

 

[harish.kaks]

Question to Gurus: can the GPS type service be available (atleast for strategic users) with launch of single satellite?

No in order to evaluate the position, signal from at least 3 or 4 satellites is required.

GPS reciever calculates the distance of itself with respect to the satellites visible to it and then it calculates its position. So it should now its distance with respect to at least 3 satellites. The accuracy increases if it is able to recieve signals from more satellites.

 

[drkrn]

@Abhi9

can u pls elaborate your statement that 1 satellite covers whole china.what does signal from satellite reaching Germany mean?

 

[harish.kaks]

Interesting news:

Germany received signal from IRNSS 1A . I always though that scope of the signal will be more than 1500 Kms outside of india. so whole china is within reach with IRNSS guidance for Nirbhaya, Brahmos and future JDAM like weapons

But germany may not recieve signals from more than one or two satellite at any point of time even after all the satellites are launched. So navigation is not possible.

 

[arnabmit]

But germany may not recieve signals from more than one or two satellite at any point of time even after all the satellites are launched. So navigation is not possible.

This is what the earth looks like from 36000km altitude where the satellites are being placed. Germany has line of sight.

Now see the location of the satellites, Germany has line of sight to 3 or more of the satellites.

 

[harish.kaks]

This is what the earth looks like from 36000km altitude where the satellites are being placed. Germany has line of sight.

Now see the location of the satellites, Germany has line of sight to 3 or more of the satellites.

Out of seven satellites , three are geo-stationary satellites , and other four are not geo-stationary they are in geo-synchronous orbits. The three geo-stationary satellites position will be stationary with respect to the earth , but the other four satellites will be synchronous to the earth so their position will not be stationary w.r.t the earth, so every time you cannot expect a picture you are showing above. And more over three satellites is a minimum requirement , but for accuracy more than 3 satellites signals are required may be four or five.

This is just my view . I may be wrong also.

 

[arnabmit]

A geostationary orbit requires that the satellite be in an orbit directly above the equator. This orbit puts the satellite in a position where it is always directly above the same spot on the planet at all times. When viewed from the earth, it will always appear stationery irrespective of the time of the day.

A geosynchronous orbit requires that the satellite be in an orbit north or south of the equator. It means that the orbit period of the satellite is the same time period of the sidereal rotation period of the Earth. In layman's terms, the satellite will be at the same locations over the earth at the same time every day.

With a geostationary orbit, the satellite will appear from Earth to be fixed in the same location in the sky all the time. With a geosynchronous orbit, the satellite will appear to move in the sky in an analemma or figure-8 pattern in the sky but would appear in the same spot every day at a certain time. (e.g. If the satellite was directly overhead at midnight on one day, it would appear directly overhead every day at midnight.)

Out of seven satellites , three are geo-stationary satellites , and other four are not geo-stationary they are in geo-synchronous orbits. The three geo-stationary satellites position will be stationary with respect to the earth , but the other four satellites will be synchronous to the earth so their position will not be stationary w.r.t the earth, so every time you cannot expect a picture you are showing above. And more over three satellites is a minimum requirement , but for accuracy more than 3 satellites signals are requires may be four or five.

This is just my view . I may be wrong also. Can you explain ?

 

[harish.kaks]

A geostationary orbit requires that the satellite be in an orbit directly above the equator. This orbit puts the satellite in a position where it is always directly above the same spot on the planet at all times. When viewed from the earth, it will always appear stationery irrespective of the time of the day.

A geosynchronous orbit requires that the satellite be in an orbit north or south of the equator. It means that the orbit period of the satellite is the same time period of the sidereal rotation period of the Earth. In layman's terms, the satellite will be at the same locations over the earth at the same time every day.

Correct , that is what i am saying, the geo synchronous satellite will come to the same place once in every 24 hours , and that's why you cannot have the same pattern of satellite positions every time in a day. It varies from time to time , But they may be designed such that at any point of time india and 1500 km around india will be able to see more than 4 to 5 satellites.

 

[Twinblade]

GUNTUR, December 14, 2013
Gagan will be put in place by end of 2014, says Defence Secretary
STAFF REPORTER

The country will put in place the GPS aided geo augmented navigation or GPS and Geo-Augmented Navigation system (Gagan), a regional satellite-based augmentation system, by the end of 2014, said Secretary, Ministry of Defence, Government of India and Director General of DRDO, Avinash Chander here on Friday.

Addressing a national seminar on "Navigation Systems & Signal Processing Applications," held on Acharya Nagarjuna University campus here, Dr. Chander said that the country's mission to send six more satellites by 2014 would be complete as the country moved towards introduction of modern communication, navigation, surveillance and air traffic management system.

"We have been dependant on Global Positioning Systems of other countries till now and we will have our own indigenously built GPS by the end of 2014. The navigation system will help monitor and navigate long range Agni missiles, nuclear submarines and warships with accuracy," Dr. Chander said.

Gagan will be put in place by end of 2014, says Defence Secretary - The Hindu

 

[shuvo@y2k10]

can the irnss be extended from 7 to about 30 satelites to provide global coverage like gps,glonass,beidou in the next decade?

 

[Eastman]

ISRO: After GSLV launch, PSLV C24 with IRNSS-1B likely in March

CHENNAI: Even as ISRO is gearing up for the launch of GSLV D5 from Sriharikota tomorrow, preparations are on for launch of the PSLV C24 carrying IRNSS-1B, which is likely in March.

"The integration process of the satellite IRNSS-1B with launch vehicle PSLV C24 was started on December 27. The launch is most likely in March," a senior ISRO official told PTI.

Since the integration is expected to take around 60 days, the vehicle would be ready by February end and the likely la ..

Read more at:
ISRO: After GSLV launch, PSLV C24 with IRNSS-1B likely in March - The Economic Times

 

[Eastman]

NovAtel Supplies Reference Receivers for IRNSS Ground Segment

NovAtel Inc., a manufacturer of GNSS precise positioning technology, has announced an agreement with the Indian Space Research Organisation (ISRO) to supply reference receiver products for use in the Indian Regional Navigation Satellite System (IRNSS) ground segment.

India-based Elcome Technologies Pvt. Limited, a sister company to NovAtel in the Hexagon Group of Companies, will provide local integration, training and technical support services for the NovAtel receivers.

These receivers are based on NovAtel's G-III reference receiver platform, the same platform used for the Third Generation WAAS Reference Receiver (WAAS G-III), which will monitor the GPS signals for the FAA's modernized Wide Area Augmentation System network.

NovAtel Supplies Reference Receivers for IRNSS Ground Segment : GPS World

 

[nrupatunga]

Source - Mangalyaan thread #post 434

In the pipeline February-March 2014

Satellite/Mission — Launch Vehicle

IRNSS-1B — PSLV

SPOT-7 — PSLV

April 2014-March 2015

Satellite/Mission — Launch Vehicle

Crew Module test — GSLV MK-III

IRNSS-1C — PSLV-C26

IRNSS-1D — PSLV-C27

IRNSS-1E — PSLV-C28

GSAT-6— GSLV-D6

GSAT-16 — Ariane-V

So 4 more IRNSS sats within next year in orbit.:thumb:

 

[praneetbajpaie]

NovAtel Supplies Reference Receivers for IRNSS Ground Segment



NovAtel Supplies Reference Receivers for IRNSS Ground Segment : GPS World

and I thought ISRO supported indigenous industry, lol

 

[Hindi]

Navigational satellite IRNSS 1-B launch set for March 31 | The Indian Express
Press Trust of India | Chennai | March 7, 2014 7:14 pm

India's latest navigational satellite IRNSS 1-B would be launched onboard PSLV C-24 rocket from the spaceport at Sriharikota on March 31.

There would be a two-and-a-half day countdown which would be preceded by a launch rehearsal on March 26, Indian Space
Research Organisation (ISRO) sources said today.

"The launch of IRNSS 1-B from the Satish Dhawan Space Centre atPSLV C-24 rocket is scheduled at 5.20 pm on March 31," they told PTI.

This is the second of the seven satellites planned for Indian Regional Navigational Satellite System (IRNSS), whose applications include terrestrial and marine navigation, disaster management, vehicle tracking and fleet management.

ISRO had launched IRNSS 1-A, the first in the series, on July 1 last year onboard its workhorse Polar Satellite Launch Vehicle (PSLV) C-22. IRNSS is similar to US' Global Positioning System (GPS), Russia's Glonass and Europe's Galileo. China and Japan too have similar systems named Beidou and Japanese Quasi Zenith Satellite System respectively, they said.

 

[cobra commando]

 

[cobra commando]

IRNSS-1B being integrated with PSLV-C24

 

[happy]

PSLV C24 launch rehearsal completed. Launch on 4th April at 5:14 PM. Countdown starting tomorrow. - Dr.M.Y.S.Prasad, Dir., SHAR.

 

[cobra commando]

IRNSS-1B Satellite on top of PSLV-C24 Fourth Stage

Two segments of the PSLV C24 Core Stage during vehicle integration at Mobile Service Tower

Fully integrated PSLV C24 Core Stage on the launch platform inside the Mobile Service Tower

 

[Soumya1989]

India's Own Satellite Navigation System by 2014 End: ISRO Chief

India is expected to have its own satellite navigation system with the launch of three more satellites before the end of this year, said the Indian space agency's chief Monday.

Indian Space Research Organisation (ISRO) chairman K.Radhakrishnan told IANS that Indian communication satellite INSAT-3E has been decommissioned couple of days ago and the users are being migrated to other satellites.

"We will be receiving the signals from our navigation satellite system by the end of this year. We will be launching three more navigational satellites before the end of this year," Radhakrishnan said over phone from Bangalore.

The ISRO will be launching the second navigational satellite badged Indian Regional Navigation Satellite System-1B (IRNSS-1B) April 4 evening at 5.14 p.m.

The 1,432 kg satellite will be carried by Indian rocket Polar Satellite Launch Vehicle (PSLV).

According to Radhakrishnan, though the IRNSS is a seven satellite system, it could be made operational with four satellites.

The two more navigation satellites will be launched during the second half of 2014.

Prior to that, ISRO will be launching the French satellite SPOT-7 and four other foreign satellites in a PSLV rocket and also test its heavier rocket - the Geosynchronous Satellite Launch Vehicle (GSLV) Mark III version, said Radhakrishnan.

The IRNSS-1B satellite with a design life span of 10 years will be part of the seven-satellite Indian regional navigational system. The first navigational satellite IRNSS-1A was launched in July 2013.

The navigational system, developed by India, is designed to provide accurate position information service to users within the country and up to 1,500 km from the nation's boundary line.

The system is similar to the global positioning system of the US, Glonass of Russia, Galileo of Europe, China's Beidou or the Japanese Quasi Zenith Satellite System.

The system will be used for terrestrial, aerial and marine navigation, disaster management, vehicle tracking and fleet management, integration with mobile phones, mapping and geodetic data capture and others.

While the ISRO is silent on the navigation system's strategic application, it is clear that the IRNSS will be used for defence purposes as well.

According to the ISRO, the IRNSS-IB has been realised within seven months of the launch of the IRNSS-1A.

Satish Dhawan Space Centre (SDSC)-SHAR director M.Y.S.Prasad told IANS: "Even if a navigation system has more than four satellites, the final precise data is picked from four satellites."

Meanwhile Indian space agency officials are getting ready for the 58 and half hour launch countdown slated to begin April 2 around 6.45 a.m.

"Normally 53 hour countdown is sufficient. But we have decided to an extended countdown so that some break time could be given for the officials," Prasad said.

On the issue of INSAT-3E satellite, Radhakrishnan said the satellite was launched in 2003 and its life span has come to an end.

"Users are being migrated to other satellites," he said.

India's Own Satellite Navigation System by 2014 End: ISRO Chief - The New Indian Express