Indian Space Program: News & Discussion - Sept 2016

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Ashokk
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Re: Indian Space Programme Discussion - Sept 2016

Post by Ashokk »

The NAVIC signal is transmitted in the L5 & S bands. The current smartphone GPS receivers are usually single frequency and receive the GPS signal in the L1/E1 band. Dual frequency receiver chips for smartphones supporting both L1/E1 & L5/E5 are just starting to become available as Galileo also has signals in the L5/E5 band. Once the dual frequency receivers become mainstream, getting NAVIC supported on the smartphones should be a trivial exercise.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Raveen »

souravB wrote: I cannot help but wonder where do all these big names like GPU, GPS, cellular modem are being placed. Oh Wait! I have already answered you, its that bold word that start with M. Now you may call me old fashioned for calling SoC a motherboard and you may be right but I have been taught that motherboards are also chip.
P.S. I can type in a hurry cause I do not need to Google things while I type but I took more time to type this post because I googled to give you a reference.

Haha, no I'll just call you wrong and move on
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Re: Indian Space Programme Discussion - Sept 2016

Post by Suraj »

JTull wrote:Give tax break for Navic compatible phones and it'll be even faster!
That's a bad idea. It has to be a mandated requirement. It's really not hard to add. The requirement is that the SoC - Snapdragon, Exynos, Axx , MTK kit etc - should support NAVIC amongst its existing support set, if that product is to be sold in India after a point. It's a negligible incremental cost, and the requirement will ensure it gets done.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Raveen »

Suraj wrote:
JTull wrote:Give tax break for Navic compatible phones and it'll be even faster!
That's a bad idea. It has to be a mandated requirement. It's really not hard to add. The requirement is that the SoC - Snapdragon, Exynos, Axx , MTK kit etc - should support NAVIC amongst its existing support set, if that product is to be sold in India after a point. It's a negligible incremental cost, and the requirement will ensure it gets done.
Agreed - mandate it, and get it over with. Others have done the same and had success, and with India being the size of market it is, it'll work.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Rakesh »

Two decades after US spurned India in Kargil, country replies with Desi GPS
http://defencenews.in/article.aspx?id=558938

What do you do when you are dependent on a global power, and it ditches you when you need it the most? You decide to become self-reliant. That's what India set out to do two decades ago, and is now on the verge of accomplishment. When Pakistani troops took positions in Kargil in 1999, one of the first things Indian military sought was global positioning system (GPS) data for the region. The space-based navigation system maintained by the US government would have provided vital information, but the US denied it to India. A need for an indigenous satellite navigation system was felt earlier, but the Kargil experience made the nation realise its inevitability. Two decades later, NavIC, India's own GPS which has been developed to challenge the current GPS system of the West, is in the final stages of launch. It will soon be offered as an Indian counter to foreign systems currently being used by companies and others.“Request for Proposal (RFP) has been called to start the implementation of NavIC so that the platform can be rolled out and popularised,” IT secretary Ajay Prakash Sawhney told TOI.

The GPS was named NavIC ('Navigation with Indian Constellation' whose Hindi meaning is 'sailor' or 'navigator'), by Prime Minister Narendra Modi after the launch of Indian Regional Navigation Satellite System (IRNSS) 1G, the last of the seven dedicated satellites, in 2016. NavIC is designed to provide accurate position information to users within the country. It will help India enter the club of select countries which have their own positioning systems. Besides America’s GPS (with 24 satellites in a constellation), Russia has its GLONASS and European Union its Galileo. Interestingly, China is also in the process of building Beidou Navigation Satellite System.

With seven satellites, the NavIC covers only India and its surroundings and is considered to be more accurate than the American system. NavIC will provide standard positioning service to all users with a position accuracy of 5 metre. The GPS, on the other hand, has a position accuracy of 20-30 metre. The indigenous navigation system is believed to have cost Isro around Rs 1,400 crore, and will aid terrestrial, aerial and marine navigation, vehicle tracking and fleet management, disaster management, mapping and geodetic data capture, visual and voice navigation for drivers.

Even more remarkable for Indian scientists is that NavIC is technically superior to the American GPS. "Our system has dual frequency (S and L bands). GPS is dependent only on L band. When low frequency signal travels through atmosphere, its velocity changes due to atmospheric disturbances. US banks on atmospheric model to assess frequency error and it has to update this model from time to time to assess the exact error. In India's case, we measure the difference in delay of dual frequency (S and L bands) and can assess the actual delay. Therefore NavIC is not dependent on any model to find the frequency error and is more accurate than GPS," Tapan Misra, the director of Ahmedabad-based Space Application Centre (SAC), told ET last year.
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Re: Indian Space Programme Discussion - Sept 2016

Post by pravula »

Rakesh wrote:Two decades after US spurned India in Kargil, country replies with Desi GPS
http://defencenews.in/article.aspx?id=558938

The GPS, on the other hand, has a position accuracy of 20-30 metre.
AFAIK, GPS has a positional accuracy of <30 cm

https://www.theverge.com/circuitbreaker ... t-broadcom
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Re: Indian Space Programme Discussion - Sept 2016

Post by Raveen »

pravula wrote:
Rakesh wrote:Two decades after US spurned India in Kargil, country replies with Desi GPS
http://defencenews.in/article.aspx?id=558938
AFAIK, GPS has a positional accuracy of <30 cm

https://www.theverge.com/circuitbreaker ... t-broadcom
The non-military grade signal open for general use isn't that accurate. Only the US mil has access to the super accurate signal, no other entity or country does.
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Re: Indian Space Programme Discussion - Sept 2016

Post by pravula »

Raveen wrote:
pravula wrote:
AFAIK, GPS has a positional accuracy of <30 cm

https://www.theverge.com/circuitbreaker ... t-broadcom
The non-military grade signal open for general use isn't that accurate. Only the US mil has access to the super accurate signal, no other entity or country does.
Nope, please read the linked article. These are for phones.
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Re: Indian Space Programme Discussion - Sept 2016

Post by rsingh »

Chinese system is supposed to be most advance (as per my Navigation teacher at yacht cub). GPS handheld device can send signal to sats like (SOS and other urgent communication).
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Re: Indian Space Programme Discussion - Sept 2016

Post by Amber G. »



The non-military grade signal open for general use isn't that accurate. Only the US mil has access to the super accurate signal, no other entity or country does.
Sorry if this has already been discussed, but one can reach accuracy (less than cm) with existing systems..(eg ground based systems which broadcasts "corrections" .. or based on similar ideas).. For example Surveying equipments in US reach that accuracy.
Theoretical accuracy for best systems (without additional other help) like US or (India) is perhaps about 2m (typical (my) phone is about 4m with 95% of the time). But high-end users boost GPS accuracy with dual-frequency receivers and or augmentation (like GAGAN) systems. These can enable real-time positioning within a few centimeters, and long-term measurements (such a surveying) at the millimeter level. Truly amazing!
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Re: Indian Space Programme Discussion - Sept 2016

Post by Amber G. »

^^^ Also, BTW as far as US is concerned- for now, and all practical purposes - the accuracy of the GPS signal is identical for both the civilian GPS service (SPS) and the military GPS service (PPS). (Thanks to Presidential policy ( post Kargil) which changed this - and some good thing Gore and some advocates like us scientists - and automobile lobby did)
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Re: Indian Space Programme Discussion - Sept 2016

Post by Raveen »

pravula wrote:
Raveen wrote:
The non-military grade signal open for general use isn't that accurate. Only the US mil has access to the super accurate signal, no other entity or country does.
Nope, please read the linked article. These are for phones.
I stand corrected on this front - thank you.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neshant »

A great documentary on NASA's Voyager's mission.
The Voyager 1 space probe is the furthest man made object from Earth. It was launched in 1977.
Its traveling through space at 17 km/sec !
A fighter jets top speed is only about 0.7 km/sec.
And yet even at that speed, it will take 40,000 years to get to the next star.

The Farthest - Trailer


The full documentary is on Youtube if you search.

More than any probe, what India needs to set its sights on is building a Hubble sized telescope in space.
And I'm not talking about some radio wave or gamma wave telescope where the public has zero interest because they can't see images of the data.
Rather something in the IR + Visible spectrum which can create amazing Hubble like colored images of distant galaxies.
That will inspire a whole generation of young Indians to dream big.
Instead of a mission to Venus, the Moon (which will quickly be forgotten) or even putting the first Indian astronaut in space, they should make an Indian Hubble space telescope a higher priority mission.
The worst idea for a project I've heard of is to build a space station - which is a total waste since it offers almost no major scientific discovery value but cost a huge amount + huge maintenance. A worthless money pit year after year.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Trikaal »

Neshant wrote:A great documentary on NASA's Voyager's mission.
The Voyager 1 space probe is the furthest man made object from Earth. It was launched in 1977.
Its traveling through space at 17 km/sec !
A fighter jets top speed is only about 0.7 km/sec.
And yet even at that speed, it will take 40,000 years to get to the next star.
They have also put phonographs aboard Voyager 1 with 'Hello' in all major languages as well as voices of many animals to depict life and culture on earth in the event the satellite gets intercepted by aliens.

Don't agree with u on Telescope. Nothing beats the optics of a man on the moon. A generation of children were inspired by Rakesh Sharma going to space. Even today, everyone remembers Rakesh Sharma's iconic reply to Indira Gandhi, "Saare Jahan se Achcha, Hindustan hmaara". A telescope can't beat that.
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Re: Indian Space Programme Discussion - Sept 2016

Post by JTull »

Correct. Launch and successful insertion in orbit of Mangalyaan gathered more news than the pictures it sends now. Same for Chandrayaan.

There's a place for science while it's another thing to capture a nation's imagination. A radio-imaging of distant galaxies is quite common now. Optical-imaging has limited use.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neshant »

Hubble provides the largest bang for the buck in terms of science per dollar.

Putting a man on the moon by contrast no longer holds any major propaganda or scientific value. It's an expensive waste.

Who even remembers China put a man in space and landed a Rover on the moon?
What if a anything was gained from it?

Probes to Mars, Venus are somewhat inbetween.
The Mangalyaan mission was an exception because India reached there ahead of China and succeeded on its fisrt attempt where other more developed countries like the UK had failed.
That shock and awe inspiration value is one time only - subsequent missions will not have as stong an impact.


Here is one of Hubble's great discoveries :

https://m.youtube.com/watch?v=5c3xuYs75IU

The James Webb space telescope which is a super Hubble in the visible and IR range is going up in 2018. So you're wrong when you say optical imaging has limited use. Personally I think it may the the telescope that finds evidence of an alien civilization (i.e an alien superstructure revolving around a star or something quite large and luminous with a definitive shape that is clearly not a natural formation).

Finally, many countries with astronomers literally beg for time on the Hubble. By comparison nobody wants any time on the two NASA rovers on Mars. An Indian Hubble would be a piece of both science and good will diplomacy.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neshant »

NASA has not even launched the James Webb space telescope yet are already designing FOUR new generation space telescopes that will ultimately replace James Webb.

Wow!

https://m.youtube.com/watch?v=7x0RpGa_IXA

India is way behind.

We need to start planning a space telescope - and have the private sector do most of the work to stimulate the culture of space based R&D.

We are going to need the private sector for space based warfare and this is one way to gear up instead of keeping everything in ISRO where the diffusion of skills across industry is ZERO.
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Re: Indian Space Programme Discussion - Sept 2016

Post by JTull »

Neshant wrote:Hubble provides the largest bang for the buck in terms of science per dollar.

Putting a man on the moon by contrast no longer holds any major propaganda or scientific value. It's an expensive waste.

Who even remembers China put a man in space and landed a Rover on the moon?
What if a anything was gained from it?

Probes to Mars, Venus are somewhat inbetween.
The Mangalyaan mission was an exception because India reached there ahead of China and succeeded on its fisrt attempt where other more developed countries like the UK had failed.
That shock and awe inspiration value is one time only - subsequent missions will not have as stong an impact.


Here is one of Hubble's great discoveries :

https://m.youtube.com/watch?v=5c3xuYs75IU

The James Webb space telescope which is a super Hubble in the visible and IR range is going up in 2018. So you're wrong when you say optical imaging has limited use. Personally I think it may the the telescope that finds evidence of an alien civilization (i.e an alien superstructure revolving around a star or something quite large and luminous with a definitive shape that is clearly not a natural formation).

Finally, many countries with astronomers literally beg for time on the Hubble. By comparison nobody wants any time on the two NASA rovers on Mars. An Indian Hubble would be a piece of both science and good will diplomacy.
NASA has not even launched the James Webb space telescope yet are already designing FOUR new generation space telescopes that will ultimately replace James Webb.

https://m.youtube.com/watch?v=7x0RpGa_IXA

India is way behind.

We need to start planning a space telescope - and have the private sector do most of the work to stimulate the culture of space based R&D. We going to need the private sector for space based warfare and this is one way to gear up instead of keeping everything in ISRO where the diffusion of skills across industry is ZERO.
Wah wah! You talk about culture of R&D, private sector, space based warfare, diffusion of skills, etc, but only judge missions by their newsworthiness.

China's manned mission made news in China and had tremendous boost to their psyche.

There have been Mars and moon missions in the past. Still Indian missions made news with Indians everywhere.

You're trying to show what was done once has no value because second time it doesn't make news. So why should India launch optical telescope just because you want it? Per your examples, it's already been done, so it would be a waste.

If we're to believe your lament that "India is way behind" onleee, let's spend our meagre rupees the way we want. There's no need to be in a race with anyone else.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neshant »

As I said, the best scienctific bang for the buck comes from a space telescope.
That is the reason Hubble is almost 3 decades old and time on it is still in high demand internationally.
Nobody gives a crap about a Rover on the moon because there is almost zero scientific discoveries coming from there.
Ditto for the rovers on Mars.
There has been FAR more in the way of discoveries coming from the Hubble than will ever come from Mars or moon rovers, space stations and other such missions consuming shitloads of financial resources.
NASA is actually hoping the 2 Mars rovers die so they can deploy those financial resources elsewhere.

Second, the China man in space and their rover on the moon came and went as a footnote.
There is no enduring scientific breakthrough or discovery which makes the endevor a poor investment.

Because a telescope targets the whole universe rather than some narrow application and because time on it is always in high demand, it is far more valuable than any one off mission.
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Re: Indian Space Programme Discussion - Sept 2016

Post by JTull »

Ashokk wrote:The NAVIC signal is transmitted in the L5 & S bands. The current smartphone GPS receivers are usually single frequency and receive the GPS signal in the L1/E1 band. Dual frequency receiver chips for smartphones supporting both L1/E1 & L5/E5 are just starting to become available as Galileo also has signals in the L5/E5 band. Once the dual frequency receivers become mainstream, getting NAVIC supported on the smartphones should be a trivial exercise.
Newest flagships like Oneplus 6 and Samsung S9 are showing compatibility with GPS, GLONASS, BeiDou, Galileo.

Garmin has started rolling out firmware updates to support Galileo on some of it's sports devices (for running, cycling, etc) that have newer chipsets.

Based on your comment, it may just be a firmware update to add Navic compatibility on these flagship devices. With cheaper models, we might see trickle down effect as these newer chipsets take hold. In the end, it'll upto the manufacturer to add support for Navic. Govt will definitely be able to incentivise (or arm-twist) desi brands.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Trikaal »

Neshant wrote:As I said, the best scienctific bang for the buck comes from a space telescope.
That is the reason Hubble is almost 3 decades old and time on it is still in high demand internationally.
Nobody gives a crap about a Rover on the moon because there is almost zero scientific discoveries coming from there.
Maybe take a look at this article?
http://idrw.org/indias-quest-for-trilli ... ore-173412
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

Peopel talking about space telescopes forget we have Astrosat which is unique in its own way wrt information. May not be big like Hubble but baby steps
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neshant »

prasannasimha wrote:Peopel talking about space telescopes forget we have Astrosat which is unique in its own way wrt information. May not be big like Hubble but baby steps
Astrosat-1 has about 2 more years of life left in it and then it's dead.

Astrosat-2 is currently being planned to replace it.

The Indian Hubble I'm talking about would take about 10 years to develop so it's not meant to be a near term project.
It can be used to test various concepts like refuelling, docking, automated maintenence and repair - all in lower Earth orbit. So it's not just a telescope but a platform on which to test these concepts. The more I think about it, the more bang for the buck it appears to offer over other projects.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Amber G. »

Neshant wrote:A
...Nobody gives a crap about a Rover on the moon because there is almost zero scientific discoveries coming from there.
Not sure if "zero scientific discoveries" part..Some say He3 mining alone may worth trillions of rupees.
For example see: India's Mission to Find and Mine Futuristic Nuclear Fuel on the Moon Is About to Launch
or The Quest to Find a Trillion-Dollar Nuclear Fuel on the Moon
[China has] put a rover on the moon, partly in order to scout out helium-3 deposits. Now India is following suit.
Actually IMO, One who develops the capacity to bring that source from the moon to Earth will dictate the process.. along with China, India is going to lead ... others (like US) don't want to be left behind. There is already quite a bit of jealousy on other players and NASA.. is going to moon too, so is Russia and Jeff Becoz.. (Japanese OTOH are cooperating with India).
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neshant »

If there were trillions to be made mining Helium-3 on the moon, the US and Russia would be there already.

The fact that they are not suggests otherwise.

Nothing can top a space telescope terms of scientific, technological and inspirational value for a space project on a limited budget. It definitely beats a one time trip to anywhere which would have no enduring scientific return unlike a space telescope.

However if such a project is undertaken (as it should) the telescope has to be at least comparable to a smaller scale James Webb and definitely better than a 30 year old Hubble. Anything less and the program planners have wasted the money and squandered the opportunity.

I would have made the Indian Hubble telescope a priority and cancelled the Venus program. The Mars and Moon program could continue but only if there is some long term plan to actually do something there. If not, one or the other would have to be cut and it's budget allocated to the space telescope.

Babuz need commission a study of it's feasibility asap if there is any hope of this program seeing the light of day in the next 10 years.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Amber G. »

Neshant wrote:If there were trillions to be made mining Helium-3 on the moon, the US and Russia would be there already.
/sigh/ Wow!
Meanwhile just for information sharing and not to "debate" pointless things..and may be put some perspective "OTOH"
From today's NY times..
>>> The long awaiting successor to Hubble Space Telescope will take 3 more years and another billion dollars to complete.

>>>It’s current bill of ~$10 Billion is about 50x the whole chandrayaan2. “The telescope that ate astronomy”
NASA Again Delays Launch of Troubled Webb Telescope; Cost Estimate Rises to $9.7 Billion

The kind of claims :
[quote]Nothing can top a space telescope terms of scientific, technological and inspirational value for a space project on a limited budget. ..
[/quote]
May not be that sound.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Amber G. »

^^^ Just to be clear - My posts about He3, Hubble etc are primarily for educational purposes -- as both items are newsworthy in their own right.
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Re: Indian Space Programme Discussion - Sept 2016

Post by kit »

i suppose s space telescope can double up as spy satellite as well... no not joking .. what do you think the American KH series satellites were :D .. literally each one of them was a mini Hubble ..only pointed the other way around :mrgreen:
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Re: Indian Space Programme Discussion - Sept 2016

Post by jaysimha »

http://www.msruas.ac.in/pdf_files/Annou ... ochure.pdf
MS RAMAIAH UNIVERSITY of applied sciences,,,,,,, one day workshop on ELECTRIC PROPULSION
6th JULY 2018
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Re: Indian Space Programme Discussion - Sept 2016

Post by jaysimha »

http://www.nesac.gov.in/download/w3.pdf

3rd BASIC COURSE
on
REMOTE SENSING AND GIS
TECHNOLOGY & APPLICATIONS
16-27 July 2018
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Re: Indian Space Programme Discussion - Sept 2016

Post by dinesha »

India's Domestic SatNav System Hits Major Roadblock Ahead of Commercial Release
https://sputniknews.com/asia/2018070210 ... roadblock/
A study conducted by Indian scientists with the support of the Indian Space Research Organization’s Ahmedabad-based Space Applications Centre warned that signals from NavIC satellites may interfere with WiFi signals in receivers.

New Delhi (Sputnik): The Navigation with Indian Constellation (NavIC) — India's indigenous navigation and positioning system — has confronted unforeseen challenges ahead of its commercial rollout slated for the next few months.

According to the ISRO, the seven-satellite constellation sends signals in frequency bands of L5 (1176.45 MHz) and S-band (2492.08 MHz). The S-band frequency is utilized by NavIC for navigation systems, which are also shared by communication systems like long-term evolution (LTE), Bluetooth and wireless fidelity (Wi-Fi).

The study, published in Current Science, found that NavIC signals are affected by out-of-band interference due to Wi-Fi signals.
"These interfering signals present a threat to the NavIC receiver performance. To equip both the facilities (WiFi and NavIC) in future cell phones, it will be a challenge to mitigate such kind of radio frequency interference," according to a study conducted by Dr. Shweta N Shah of the electronics engineering department at Sardar Vallabhbhai National Institute of Technology, Surat, and Darshna D. Jagiwala.


In the experiment, the scientists found that a part of the S-band of NavIC systems overlaps the unlicensed band that is shared by other communication technologies like Bluetooth, Wi-Fi and Industrial Scientific Medical (ISM) bands.

In India, Wi-Fi signals are exempted from licensing in the frequency band ranging between 2400 and 2483.5 MHz. This means the usable part of any Wi-Fi system or channel in India must be contained within 2483.5 MHz.

"Residual or unintended signals normally go beyond this limit due to the basic characteristic of digital emissions. The NavIC signal is centered at 2492.08 MHz with a bandwidth of ± 8.25 MHz. This means that the lower part of NavIC signal can get interference from residual/unintended signals of Wi-Fi systems. Also, the upper part of the NavIC signal goes beyond 2500 MHz and since the frequency band above 2500 MHz is used for other purposes, NavIC receivers can pick up signals (and receive interference) from such other systems operating above 2500 MHz," explained Mr. Pawan Kumar Garg, a former wireless advisor to the Indian government, while speaking to India Science Wire.

The NavIC is an independent regional navigation satellite system designed to provide positional information in the Indian region and 1,500 km around the Indian mainland.
The ISRO claimed that the NavIC is way more accurate than systems developed by its foreign competitors and would provide a standard positioning service for terrestrial, aerial and marine navigation, vehicle tracking and fleet management, mobile phones, visual and voice navigation for drivers, with a position accuracy of five meters. GPS, on the other hand, has a position accuracy of 20-30 meters.

READ MORE: India to Make Native Navigation System Mandatory For All Aircraft

The constellation of the navigation satellite was completed earlier this year with the successful replacement of one of the satellites within the Indian Regional Navigation Satellite System-1I (IRNSS-1I). This was the second attempt by ISRO to replace the faulty satellite since the first attempt was doomed due to the heat-shield failure of the Polar Satellite Launch Vehicle (PSLV) in August last year.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Neshant »

Isro’s Astrosat captures image of galaxy cluster 800 million light years away

Image

https://timesofindia.indiatimes.com/hom ... 836364.cms
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

Padabort test is planned according to the SANavarea warning deciphered by Kurup
T
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Re: Indian Space Programme Discussion - Sept 2016

Post by chetak »

Raveen wrote:
pravula wrote: AFAIK, GPS has a positional accuracy of <30 cm

https://www.theverge.com/circuitbreaker ... t-broadcom
The non-military grade signal open for general use isn't that accurate. Only the US mil has access to the super accurate signal, no other entity or country does.
NATO does, no??
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Re: Indian Space Programme Discussion - Sept 2016

Post by chetak »

rsingh wrote:Chinese system is supposed to be most advance (as per my Navigation teacher at yacht cub). GPS handheld device can send signal to sats like (SOS and other urgent communication).
There are wrist watches that have been doing this for years. Available freely and commercially.
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Re: Indian Space Programme Discussion - Sept 2016

Post by Kakarat »

Better Image of Astrosat galaxy cluste

https://twitter.com/SJha1618/status/1014117266219249664
So @isro's Astrosat provides us with a 'deepest look' at galaxy cluster 'Abell 2256', located some 800 million light years away from Earth. The on board ultraviolet imaging telescope collected light from the cluster in three narrow-band filters in the near UV wavelength region.
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Varoon Shekhar
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Re: Indian Space Programme Discussion - Sept 2016

Post by Varoon Shekhar »

For the pad-abort test scheduled for tomorrow, what is the vehicle that will be used, and what is the size of the Crew module?
prasannasimha
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Re: Indian Space Programme Discussion - Sept 2016

Post by prasannasimha »

The pad abort test by definition has to be using an equivalent of the crew module

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dinesha
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Re: Indian Space Programme Discussion - Sept 2016

Post by dinesha »

Varoon Shekhar
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Re: Indian Space Programme Discussion - Sept 2016

Post by Varoon Shekhar »

How is it being sent up? Or will we only know that tomorrow? Unless it's a miniaturised version of CARE, it has to be a launch vehicle. Or is it air dropped by a transport aircraft?
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