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GPS Outage NOTAM Affects GLONASS?


Jerry 5TJ

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Do the GPS jamming sessions also take down GLONASS? I ask as some newer iPad models and the Area 660 track both systems.  If only GPS is jammed in scheduled events such as 

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then a receiver that also uses GLONASS signals would seem a worthwhile backup to have available.  

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2 hours ago, Jerry 5TJ said:

Do the GPS jamming sessions also take down GLONASS? I ask as some newer iPad models and the Area 660 track both systems.  If only GPS is jammed in scheduled events such as 

...

then a receiver that also uses GLONASS signals would seem a worthwhile backup to have available.  

GPS and GLONASS use different frequencies.   They're both L-band-ish, but don't occupy the same frequencies within the band.    Somebody with a broadband jammer could interfere with both simultaneously, but if somebody were intending to test GPS jamming susceptibility they could do it without interfering with GLONASS or other users in L-band.   Since there's a lot of other stuff in the band, e.g., other satellite comm that are primary users, I doubt they'd be spraying willy-nilly everywhere.   My expectation would be that any of the other GNSS satellite nav systems should be fine during gps testing outages.

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14 hours ago, Steve W said:

I have to wonder if they're testing GLONASS jamming but not actually putting out NOTAMS for that since it's not presently(officially) used for navigation in the US.

 

Bingo.   I think they are jamming the russians, and the US GPS is possible collateral damage.

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9 hours ago, Yetti said:

Bingo.   I think they are jamming the russians, and the US GPS is possible collateral damage.

If they knock out our own system when they're jamming the Russians we have an extremely poor jamming strategy.

 

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1 hour ago, EricJ said:

If they knock out our own system when they're jamming the Russians we have an extremely poor jamming strategy.

 

hence why you do the testing.  After all it is a very low power signal coming all the way from space. ok nearby space but all the same it is still space.

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  • 2 years later...
On 11/18/2019 at 11:48 AM, Jerry 5TJ said:

Do the GPS jamming sessions also take down GLONASS? I ask as some newer iPad models and the Area 660 track both systems.  If only GPS is jammed in scheduled events such as 

71ACCFEF-560B-4992-B418-81A3C0A22FC9.thumb.jpeg.69e9e1996a1907460818b49d98197eb2.jpeg
 

then a receiver that also uses GLONASS signals would seem a worthwhile backup to have available.  

Don’t mean to resurrect an old thread, but I was bored today as my autopilot was flying me home and started playing with my Aera 796 and noticed it does use GLONASS. I’m assuming the GTN750/650 don’t. Has anyone had experience with their portable unit (or iPad) working whenGPS is unavailable?

 

171D5AAD-8121-4FDA-9117-85CE08912A71.jpeg.29eaaa2ffb4fbad02d689a54c97db614.jpeg

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1 hour ago, carusoam said:

Trust Russia with your navigational needs?   :)

-a-

Trust, but verify. Just curious based on the differences people mentioned above if it's an alternative for when GPS is down. Obviously not as a primary source.

I grew up being told "it's the USSR, not Russia." I guess now it's Russia. Maybe in the future it will be the USSR again.

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3 minutes ago, ilovecornfields said:

Trust, but verify. Just curious based on the differences people mentioned above if it's an alternative for when GPS is down. Obviously not as a primary source.

I grew up being told "it's the USSR, not Russia." I guess now it's Russia. Maybe in the future it will be the USSR again.


I’m not sure who owns the glonass system Today, or where you go for notams for it….

Last time the Winter Olympics were Sochi….  Russia celebrated by visiting its neighbors….

 

Back in the day it was the USSR and we trained to dismantle their hardware with alacrity….  :) 

 

In the news today… solar storms have taken a few SpaceX satellites out of their orbits….   Kind of expensive storm damage of the global variety… an example of needing to know that the satellites you want, may go off line for some reason…

 

Any port in a storm… is a good port… when you need it…

 

Use caution…. We have many good MSers of Russian and Ukraine descent…. We don’t want to accidentally bash good MSers…

We have accidentally bashed the ‘Chinese’ when we meant to bash China and it’s government.

 

Go MS!

:)

Best regards,

-a-

 

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1 hour ago, carusoam said:

Last time the Winter Olympics were Sochi….  Russia celebrated by visiting its neighbors….

Didn’t you hear? He promised not to invade until AFTER the Olympics are over. Truly a grand gesture.

Not trying to offend anyone. I have nothing against the citizens of either country—just not fond of some of the current world leaders.

I kind of miss Gorbachev. At least he had that cool port-wine stain on his head and was kind of predictable. One of my favorite Daily Shows was when Jason Jones interviews him and he threatens to throw him against the wall.

 

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I believe the current cellular iPads can use GPS, GLONASS and Galileo. I keep an iPad handy (trust, but verify Garmin :)). I’ve never experienced a GPS outage, but it would be interesting to see how the iPad does during one that kills my Garmin boxes.

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5 hours ago, PT20J said:

I’ve never experienced a GPS outage, but it would be interesting to see how the iPad does during one that kills my Garmin boxes.

During a GPS jamming event in 2021 the panel-mounted Garmin units quickly annunciated the loss of GPS signals and X-ed out their affected displays.  

However, the iPad running ForeFlight did not revert to other satellite navigation sources, nor did it flag or blank the map display.  The symbolic airplane just coasted along the Magenta Line showing the previous heading and speed.  

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Currently the FAA only allows certified NAV systems to use GPS, however, GALILEO is nearly in the regulations, so expect that to become available in the next few years.  (part of why I'm holding off on avionics upgrades...it's a HW change).  

Consumer devices and handhelds can use a multitude of GNSS signals.  GPS, GALILEEO, GLONASS, BEIDOU.  There are also regional signals like QZSS.  Newer phones also use L1 and L5 frequencies from GPS and GAL, some also have BEIDOU. 

Most of the constellations have multiple frequency bands to help with interference/jamming, atmospheric delays, and mulitpath.  https://www.tallysman.com/gnss-constellations-radio-frequencies-and-signals/    When one tests jamming it could be multiple types of tests as people mentioned.  It could be broad spectrum, specific bands, or constellations.  It depends on what offense/defensive solution is being tested.   One can also be testing directional antenna solutions like CRPA to null out a jammer or spoofer.

Having a tablet with GNSS, not just GPS, and VOR capability in the panel is a great backup.

Jamming and spoofing are not the only challenge for GPS/GNSS.  The signals can be blocked by buildings and terrain.  That's not an issue for Mooney pilots, but is an issue for drones, air-taxis, cars, and anything on the ground.   There is now technology that can predict GNSS conditions to route around denied areas, or improve performance by enabling the GNSS receiver to prioritize the best signals.   https://www.spirent.com/products/gnss-foresight-forecasting

 

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I would think ours and theirs weapons systems use all available navigation sources to hit its target. If you want to deny navigation or spoof the navigation of your enemy, you have to do them all. I would assume they will fall back to inertial navigation and ded reckoning if they lose satellite navigation or the satellite solution differs from the internal solution.

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28 minutes ago, N201MKTurbo said:

I would think ours and theirs weapons systems use all available navigation sources to hit its target. If you want to deny navigation or spoof the navigation of your enemy, you have to do them all. I would assume they will fall back to inertial navigation and ded reckoning if they lose satellite navigation or the satellite solution differs from the internal solution.

There are dozens of systems and sources depending on the phase, criticality, and type of system.  It's a complex challenge in both civil and military applications.  Each has different failure modes, finding the right mixture at the right cost leads to some fun engineering.

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20 minutes ago, Boilermonkey said:

There are dozens of systems and sources depending on the phase, criticality, and type of system.  It's a complex challenge in both civil and military applications.  Each has different failure modes, finding the right mixture at the right cost leads to some fun engineering.

When everybody or nobody is happy with the agreed upon solution, you have reached engineering nirvana and it is time to build it.

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FWIW, I was just poached from my job by a new biotech startup. We spent the last week locked in a conference room deciding (arguing) on how this instrument would be built. I got my butt hurt a few times, but there is still a lot of me in the concept. It's not good engineering until there are a few good fist fights. But it's all good, we go have beers at the end of the day and congratulate each other on the awesome progress we are making.

This thing will change the world, if you are one of those molecular biology geeks.

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4 hours ago, N201MKTurbo said:

I would think ours and theirs weapons systems use all available navigation sources to hit its target. If you want to deny navigation or spoof the navigation of your enemy, you have to do them all. I would assume they will fall back to inertial navigation and ded reckoning if they lose satellite navigation or the satellite solution differs from the internal solution.

One good EMP hit will take out pretty much everything.  ;)

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7 minutes ago, EricJ said:

One good EMP hit will take out pretty much everything.  ;)

Sure go for the nuclear option!

I know there are conventional EMP weapons.

I still have an E6B and know how to use it. I might still have some very stale paper charts.

Edited by N201MKTurbo
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28 minutes ago, N201MKTurbo said:

Sure go for the nuclear option!

I know there are conventional EMP weapons.

I still have an E6B and know how to use it. I might still have some very stale paper charts.

And two magnetos.    Those electronic things won't work at all after an EMP hit.  ;)

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  • 2 weeks later...
On 2/12/2022 at 12:32 PM, EricJ said:

And two magnetos.    Those electronic things won't work at all after an EMP hit.  ;)

My 1948 Willy's CJ2A is EMP proof, so I can drive it to the airport.  The M20 will start, and allow my to fly until I can't fill up with fuel because all the electronic card-actuated gas pumps will be shot...   Maybe start flying with a pipe wrench and long siphon hose?

  We'd all mostly be screwed.  Hope it never comes to that.

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Recently read an article (MS Thesis) comparing the different GNSSs.   GLONASS uses a different frequency for each satellite.  A test done by the Norwegian Navy showed that jamming GLONASS requires about 7dB more power than that required to jam GPS. 

The GPS system specs are ridiculous.  -150dBm power levels at our receiver!!  A low power transmitter is all it takes to overwhelm any GNSS system.   In another thread there was a good discussion of the need for a more powerful ground-based GPS system, especially around airports.

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