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Old 22-09-2014, 03:35   #241
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Re: What will Happen to you when GPS goes Down

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Originally Posted by estarzinger View Post
Hmmm. . . . If you think that you are unaware of what the U.S. Military has been doing ever since the Iranians hijacked that stealth drone by fiddling the gps system.

Plan: Micro-Technology for Positioning, Navigation and Timing (Micro-PNT)

And the result: 2013/04/10 Extreme Miniaturization: Seven Devices, One Chip to Navigate without GPS

The U.S. Military very clearly intends to deny enemy forces uses of GPS, while it uses these more protected systems.

firstly you will notice the first line

Quote:
The U.S. Military relies on the space-based Global Positioning System (GPS) to aid air, land and sea navigation.

That is the case today and will continue, I used to work in the defense industry, ( many years aqo) GPS is embedded into all aspects of the modern military and is becoming more so.

Furthermore RQ-170, as was later acknowledged was not brought down by GPS spoofing, the Drone doesn't use GPS as its primary navigation system, its uses Inertial Navigation ( which Darpa is miniaturising) . Inertial navigation is also used ( or was used) on cruise missiles etc.

GPS spoofing will be solved ( and is being solved) in the new launches and the proposals to cryptographically encode GPS and other military signals.


IN civilian world the best bet against spoofing is the use of multiple source signals, todays SMARTphones all contain chipsets that can read 4-5 proposed and launching GNSS systems.

http://radionavlab.ae.utexas.edu/ima...alk_Wesson.pdf

The primary reason the US military is investigating miniaturising internal navigation systems, is that it wants the ability to selectively deny the enemy use of GNSS, while retaining some ability to use its own systems. This is no more then radio jamming conventional data system thinking. It in practice cannot degrade worldwide GNSS usage without i effect engaging in a space battle with several very large powers, all of which would have consequences that mean the last thing on the minds of cruisers would be where they are.( we'd be trying to avoid all that glass !).

None of this has any relevance to cruising whatsoever, The worldwide civilian GNSS system is not fully in the US's control and is increasingly less so. Its worth to the civilian powers is such that its like electricity.

Cruisers need have no fear of its termination. We might as well start a discussion on "end of world" nonsense topics etc.


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Old 22-09-2014, 04:54   #242
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Re: What will Happen to you when GPS goes Down

FWIW, the signals used by the military are a different freq than the signals we use, and as far back as the first gulf war, to use the military signal you had to have a secure "fill" in your GPS receiver.
So civilian GPS can be turned completely off with no effect to the US military, or the civilian signal through SA can be degraded in accuracy to any extent desired.
SA is simple, every so often the satellite will send an incorrect time signal is all, how far off it is time wise and how often it sends a lie determines the accuracy.
Clinton turned off SA in 2000, original accuracy for civilian use was 100m, then 20 after SA was turned off, and now I think with WAAS its 10 or a little less?
Supposed reason for SA was to keep someone from building a cheap cruise missile out of an old Cessna etc., but rumor had it Bill turned off SA to further delay GLONASS as with SA it was going to be more accurate than the US system, but without SA, it would be less accurate.
Or so were the rumors were when I was still active duty.
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Old 22-09-2014, 05:16   #243
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Re: What will Happen to you when GPS goes Down

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FWIW, the signals used by the military are a different freq than the signals we use, and as far back as the first gulf war, to use the military signal you had to have a secure "fill" in your GPS receiver.
So civilian GPS can be turned completely off with no effect to the US military, or the civilian signal through SA can be degraded in accuracy to any extent desired.
SA is simple, every so often the satellite will send an incorrect time signal is all, how far off it is time wise and how often it sends a lie determines the accuracy.
Clinton turned off SA in 2000, original accuracy for civilian use was 100m, then 20 after SA was turned off, and now I think with WAAS its 10 or a little less?
Supposed reason for SA was to keep someone from building a cheap cruise missile out of an old Cessna etc., but rumor had it Bill turned off SA to further delay GLONASS as with SA it was going to be more accurate than the US system, but without SA, it would be less accurate.
Or so were the rumors were when I was still active duty.
Military GPS systems will typically use the C/A ( coarse acquisition) to perform initial calculations and then the encoded P/Y to generate the more precise location codes. This is actually the way the system was designed , in reality it had no civilian purpose, but the C/A coding was seen to provide sufficient accuracy for civilian uses and hence the industry was born.

IN reality SA was turned off, because of two things, firstly the military demonstrated that it could easily selectively deny GNSS signal availability in local theatres and secondly the burgeoning use of commercial devices, meant that GPS and GNSS in general was becoming essential to modern civilisation.

Both GLONASS and Galileo are capable of better accuracies, The EU has had a debate about charging for theses accuracies ( thats if it ever gets the rest of the systems up there). Newer GPS IIF and III birds will also be capable of better accuracy.

Note that, Block IIF currently being deployed does not even have the selective availability hardware anymore

Civilian receivers using various techniques can achieve quite amazing accuracies, often down to 10-50mm. Newer multiple GNSS capable receivers can also use these different systems to achieve better and better accuracies.

Certainly within the next 10 years well be swimming in GNSS systems . ( US, Russian, Chinese, EU, Japan, India etc )


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Old 22-09-2014, 05:27   #244
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Re: What will Happen to you when GPS goes Down

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I used to work in the defense industry, ( many years aqo) GPS is embedded into all aspects of the modern military and is becoming more so.

mmm . . . just FYI, I work in the defense industry TODAY, with DARPA (augment reality systems).

Inertial navigation is also used on cruise missiles etc.

Yes, exactly. Unlike what you said above. The US military at least has been working very hard to reduce their vulnerability to gps by developing and deploying better/smaller inertial systems. I want one on my boat - would work much better than my fluxgate when I get near the mag north pole.

The primary reason the US military is investigating miniaturizing internal navigation systems, is that it wants the ability to selectively deny the enemy use of GNSS, while retaining some ability to use its own systems.

Yes, exactly, although they also want to reduce their own vulnerability to the same actions by an enemy.

None of this has any relevance to cruising whatsoever, The worldwide civilian GNSS system is not fully in the US's control and is increasingly less so. Its worth to the civilian powers is such that its like electricity.

hmmm . . . . you do realize that nuclear electrical plants (just for instance) do go down, as for instance in a tsunami. You are confident that there will be never by meteor showers or solar incidents nor human error, that would degrade the (multiple) sat constellation?

After all, by your arguments in the other thread, why not learn DR and/or celestial, first simply as "Insurance". And second, you think boaters need to be more 'knowledgeable'. Suggesting they can/should depend on gps (which unfortunately leads to 'point and click navigation approaches') does not help that aim much, and convincing them to learn navigational practice would.
.......
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Old 22-09-2014, 05:42   #245
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Re: What will Happen to you when GPS goes Down

Evans, in this thread you are worried about the possibility of all worldwide GPS systems going down from military intervention, meteor showers or solar incidents - and the resulting effects on navigating a recreational sailboat.

In another thread, you advocate not having an epirb or liferaft because the probability of ever needing one is low and having them would cause one not to focus on the problem at hand.

You also claim (and appear) to have a firm grasp of actuarial statistics and probability mathematics.

I'm confused. Maybe you just like debates?

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Old 22-09-2014, 05:52   #246
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Re: What will Happen to you when GPS goes Down

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I used to work in the defense industry, ( many years aqo) GPS is embedded into all aspects of the modern military and is becoming more so.

mmm . . . just FYI, I work in the defense industry TODAY, with DARPA (augment reality systems).

Inertial navigation is also used on cruise missiles etc.

Yes, exactly. Unlike what you said above. The US military at least has been working very hard to reduce their vulnerability to gps by developing and deploying better/smaller inertial systems. I want one on my boat - would work much better than my fluxgate when I get near the mag north pole.

The primary reason the US military is investigating miniaturizing internal navigation systems, is that it wants the ability to selectively deny the enemy use of GNSS, while retaining some ability to use its own systems.

Yes, exactly, although they also want to reduce their own vulnerability to the same actions by an enemy.

None of this has any relevance to cruising whatsoever, The worldwide civilian GNSS system is not fully in the US's control and is increasingly less so. Its worth to the civilian powers is such that its like electricity.

hmmm . . . . you do realize that nuclear electrical plants (just for instance) do go down, as for instance in a tsunami. You are confident that there will be never by meteor showers or solar incidents nor human error, that would degrade the (multiple) sat constellation?

After all, by your arguments in the other thread, why not learn DR and/or celestial, first simply as "Insurance". And second, you think boaters need to be more 'knowledgeable'. Suggesting they can/should depend on gps (which unfortunately leads to 'point and click navigation approaches') does not help that aim much, and convincing them to learn navigational practice would.

You really are "angels on the head of a pin" merchant, Evans.

Firstly GPS systems are widespread in the Military, They are unlikely to be any less so in the coming years.

All militaries are looking at various systems to ensure their continual ability to operate in the face of many types of electronic warfare. This is normal, ( for example its a major factor in wire guided missiles for example) That in itself has no impact on civilian systems anyway.

I never argued that anyone shouldn't learn celestial, personally one of my hobbies is "ancient" navigation , I can even do Lunars.

But I wont sit here today, and argue that the average ocean sailor need celestial because on the off chance that the whole global GNSS system will fail.

Not withstanding the fact that the sun will continue to set in the west, and the major landmasses are more or less where they always were.!!!

To decry reliance on a technology based on the remote possibility of total system failure is quite frankly nonsense, and would in effect render most technology today unusable by the same measure.

All systems have failure modes, some of those failure modes even result in death, SO what. it doesn't invalidate their use, if that use is of sufficient value. ( cars for example)

GNSS is a worldwide available and resilient technology and has proven itself to be so, postulating ever more ridiculous scenarios reminds me of the "survivalist " nonsense.

If the global GNSS fails, I suspect you or I will have far more pressing matters to attend to then worrying about where we are, I suspect looting the local food store will be higher on our list.!!!:bang head:


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Old 22-09-2014, 06:25   #247
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Re: What will Happen to you when GPS goes Down

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This is why we always have multiple GPSs. We have a GPS on the boat but also have Navionics app on our iPad, Galaxy Tablet, and two cell phones. Not to mention the hand-held GPS that just gives a GPS reading. At all times we have a minimum of 4 units running Navionics and a basic backup (no integrated charts). We like the Navionics app b/c it's accurate, easy to use and can be installed on multiple units once you've purchased the app.
I think the focus on GPS in this thread is on the global providing (transmitting) system itself going down - not on individual receiver problems.

Having GPS backups to backups is a very good idea. In fact, it is almost unavoidable in today's world. We have GPS's built into our point and shoot cameras! I bet if you really investigated all your electronical doodads, you may find you have even more GPS's on board than you think!

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Old 22-09-2014, 06:42   #248
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Re: What will Happen to you when GPS goes Down

I'm slowly working this book:

Emergency Navigation: Improvised and No-Instrument Methods for the Prudent Mariner,
by David Burch

There are certainly more options than just "head east towards the sunrise" and with instruments on can build with a board and piece of string.
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Old 22-09-2014, 06:45   #249
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Re: What will Happen to you when GPS goes Down

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I'm slowly working this book:

Emergency Navigation: Improvised and No-Instrument Methods for the Prudent Mariner,
by David Burch

There are certainly more options than just "head east towards the sunrise" and with instruments on can build with a board and piece of string.

indeed, but following the sun worked for the Portuguese , it will work for me too !! ( and a simple hand measurement of Polaris !)

Sailing down a latitude is not rocket science.
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Old 22-09-2014, 08:13   #250
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Re: What will Happen to you when GPS goes Down

Besides positioning and navigation services, GPS delivers a timing service. This timing service is used not only by navigators, but also by suppliers of:
  • electric power
  • telecommunication/communication/radio broadcast
  • transportation (land, sea, air)
  • financial services
  • emergency response activities
  • internet
  • etc.
Loss of this critical timing service for a certain period will lead to very high costs. E.g., the total annual cost in the US of larger blackouts only is estimated at $100B per year. Probably not of much importance for captain Sailor (although beside his GPS reception, also his AIS system and synchronized lighthouses can be influenced), but certainly important for Mr. Sailor, as a member of a much larger community.
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Old 22-09-2014, 09:28   #251
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Re: What will Happen to you when GPS goes Down

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Yes, that seemed stupid at the time but you have selective memory. The replacement system was a few hundred million and that was part of budget cutting. Since there was no money to modernize a 50 year old system that no one used they decided to save the op-ex.



If within a few hundred meters of a highway then most cruisers can pretty easily navigate without GPS. But the reality is that these truckers are getting busted. And then they are getting fired. And any disruption to inland navigation is temporary as they drive on by. And because my boat moves a bit slower than an airliner I'm not worried about this at all.

No I don't have selective memory. The replacement system is GPS. Which has an annual maintenance cost of $400M (http://www.rand.org/content/dam/rand...MR614.sec5.pdf) plus periodic replacement of the satellites which annualized works out to $600M or so per year. Keeping Loran would have been about 5% the cost of the GPS system annually.

Cost issues aside the US and most cruisers have put all their eggs in one basket.

Having multiple GPS units is a solution for several different forms of local system failure but does nothing for widespread system failure such as loss of some or all the satellites. But, you say, that can't happen, never has, never will. 3 countries have anti satellite weapons and if any of those 3 goes at it with one of the others count an all the nav satellites becoming debris that will make putting up new ones a lot more expensive and risky.

Ignoring that possibility go back and look at the discussions in space weather circles a week and a half ago when we had a near miss by a coronal mass ejection. It was a moderate size ejection that would have created a class 3 magnetic storm if it had hit us probably with some satellites lost. A direct bit by a large ejection likely would kill most of the satellites. It would also trip off most of the large power grids in the world.

How many out there have a dual or tri system receiver that can pick up one of the other orbital systems Glonas or Galileo? How many have a sextant and the books to use it?

Not having a separate navigation system to back up GPS is like going offshore without a liferaft/lifeboat and/or EPIRB.

THe odds of needing the backup are low but the costs of not having one when you need it are very high.


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Old 22-09-2014, 09:50   #252
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Re: What will Happen to you when GPS goes Down

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Newt,

I don't think the Navy would do that intentionally. They would have to answer to some officials at NTIA that would be pretty upset. I also don't think many fishing vessels have GPS jammers. Mainly the jamming today is from state sponsored entities such as North Korea and some in the middle east. The PNW should be pretty safe from jamming.

You might want to check your charts because there are restricted areas and it's a good idea to know when you should avoid those.
Hi Dan,
Yeah I know where the restricted areas are and stay out of them. I just watch the exercises from outside and listen to the VHF. I think they will evenually have to do something or there will be an accident.
Actually, the fiords in the BC area do a pretty good job of jamming. But it doesn't matter much to me cause we already know we are in Chatham inlet or Blackfish sound and we are not going to run into the granite wall...
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Old 22-09-2014, 10:44   #253
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Re: What will Happen to you when GPS goes Down

Adelie,

No, the replacement was not GPS. It was eLoran and that is being deployed in a few places but not the US.
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Old 22-09-2014, 12:15   #254
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Re: What will Happen to you when GPS goes Down

As far as killing satellites, that is not as easy as you may think, the GPS satellites can maneuver, and there are several replacements already in orbit, but not in the correct orbit and powered down.

No, I think if a failure is going to happen, it far more likely to be a huge solar flare, in 1859 there was such an event, here is a Wiki article, I know Wiki is not absolute, but verify
Solar storm of 1859 - Wikipedia, the free encyclopedia
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Old 22-09-2014, 12:58   #255
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Re: What will Happen to you when GPS goes Down

The newest GPS satellites being launched are much more hardened against solar flares. I read an article where they stated they believed them to be pretty much immune to even large ones.

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