New Air Force Satellites Launched To Improve GPS (techcrunch.com) 77
AmiMoJo writes: This morning, the United Launch Alliance (ULA) successfully launched a Boeing-built satellite into orbit as part of the U.S. Air Force's Global Positioning System (GPS). This $131 million satellite was the final addition to the Air Force's most recent 12-satellite GPS series, known as the Block IIF satellites. The GPS Block IIF satellites were launched to improve the accuracy of GPS. Before the Block IIF series, the accuracy of GPS could be off by 1 meter. With the new Block IIF satellites in place that error is down to 42 centimeters.
Re:Accuracy for WHOM? (Score:4, Informative)
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RTK is more accurate than 42 cm. But that is not true GPS I suppose.
DGPS is accurate to 10 cm though.
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RTK is more accurate than 42 cm. But that is not true GPS I suppose.
What? Why wouldn't using GPS for position information be "GPS"?
DGPS is accurate to 10 cm though.
If DGPS is "GPS" then so is RTK. Both require fixed station correction information. RTK adds in phase measurements of the GPS carrier signal to get to cm accuracy.
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I know how RTK works, I've built my own RTK systems. Seeing that there are differences in RTK, some might say it isn't traditional GPS, so I left the variable in my comment in case someone had a pedantic argument about how it is interpreted making it something different.
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I thought that with the newest satellites, that capability had not been designed-in?
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Which is exactly why there's such a push for non-GPS and inertial technologies in the military. GPS is slow (to get a good track), inaccurate (depending on terrain and such), and easily spoofed.
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Besides, in time of war, the enemy will just track you using your cellphone transmitter and drop a bomb on you that way. There's the old saying, "there's no such thing as 'close enough', except in horse shoes, hand grenades ... and atom bombs."
SA meh. (Score:2)
I remember when SA was on, and there were plenty of ways to improve your accuracy, only that back then it wasn't instantaneous and involved post-processing (which we used to do to everything). So ya if you were out in the field walking along with your GPS, it could be out by a lot... However if you stood in one place for a few minutes, collected a few hundred points and then averaged them out statistically after the fact, you could get very accurate results. If you really wanted even better accuracy there u
Re:SA meh. (Score:4, Informative)
all that "post-processing" could probably be done on the fly if you really needed to, provided things like base stations still existed,
WAAS and DGPS ground stations are all over the place, and you can access the DGPS correction data using a wireless modem. It is used for maritime and aviation navigation at a minimum.
The concern that created SA was not for long-term stationary measurements, but on-the-move guidance for troops and weapons systems which would not have nearby fixed station correction data.
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> used to be a ton of "base stations"
I believe you are speaking of LORAN. Read more at wikipedia. [wikipedia.org]
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In the context of GPS and SA, he was most likely referring to DGPS [wikipedia.org]. It's not really antiquated (and you can read more at wikipedia).
Re:Accuracy for WHOM? (Score:5, Informative)
RTK GPS is accurate to within 1-2 cm lat/long and typically 2-3 cm alt. For now that is about the best accuracy a civilian can get.
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yes or the 10cm cm with DGPS. Buckyballs will allow for accuracy to about 1mm if they are used for time sync on satellites.
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Does RTK allow to get this resolution on realtime from a fast moving object, like fighter or missile ?
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This launch was actually on Feb. 5, 2016 (Score:1)
The dateline on the story is actually for Feb. 5. Spacenews.com also reported the launch was on Feb. 5.
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phones already use cell towers and wifi networks which are a lot more accurate and faster than GPS
I am not sure about this, but I had thought that phones use cell towers and wifi to get general idea where they are at and then use GPS for more accuracy. Without the inital gross location, GPS takes a lot more time to sync up.
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A-GPS downloads the GPS almanac and ephemeris data from wifi or cell towers. That way the GPS unit doesn't have to wait for this information to be sent by the satellite.
If the signal is interrupted during the satellite download, it has to start again. This can happen if your GPS antenna is a tiny thing buried inside a cellphone...
Re:Good for consumers? (Score:4, Informative)
No they aren't. They use a lot less battery power, but they provide far less accurate results. But if you want to keep the location on for an extended period, you need to use network or you'll kill your battery.
Want proof? Look at your maps app- it still uses GPS. And it eats through battery- you can feel your phone heat up when using it, and you can see the battery drop like a rock when navigation is on.
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Battery usage depends on the chipset, with newer chipsets using less power. For example, I've had a misbehaving app leave on the GPS on my Nexus 5X, and I still got battery life of about 8 hours. That's not good battery life, but the power consumption was low enough that I didn't notice the phone heating up in my pocket, and I was able to get through a day at work before it went into power saving mode.
My impression is that the real killer with the map app is screen usage. If you leave the map in the fo
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Screen usage doesn't hurt, but its the GPS using power. Generally screen is the most expensive use of power when turned on, but GPS is in the top 4.
Thanks for the tip (Score:2)
Google Maps has a feature where, when your battery gets low, it will ask if you want to dim the screen except when coming up to turns. I'd love the option to enable that behavior full time. Just going back to the home screen is a decent second choice, I suppose.
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Want proof? Look at your maps app- it still uses GPS. And it eats through battery- you can feel your phone heat up when using it, and you can see the battery drop like a rock when navigation is on.
Now for a trick, turn the navigation on and TURN OFF THE SCREEN. Just use voice based navigation.
GPS uses a lot of juice compared to many things on a phone but it is far from the biggest consumer in a navigation session which is easily 75% the fact that the screen is on permanently.
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phones already use cell towers and wifi networks which are a lot more accurate and faster than GPS
No on the accuracy. Cell tower based location determination is accurate to about a city block and provided that you have WiFi with a known location you could get accuracy to about 2 buildings. The quicker to acquire seems like it may be reasonable but by having a better guess of your location you can get a lock quicker with GPS.
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even in the late 90s, early 2000s, the cell tower triangulation allowed for 3-5 metre accuracy in cities. i don't remember if it was gsm 900 or whether it needed a 2G network (1800MHz) but that was what police in europe often used to bust criminals.
hence the popularity of nokia 6110, 6150, 6210 a 7110 among criminals where the "net monitor" part of menu could be activated. here you'd select association with a single BTS (by selecting a "bts test") and that was the end of triangulation. all the police would
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Cell tower based navigation is correct to the rough position based on relative signal strengths of the connected tower. In dense areas this could put you within a city block. In sparsely populated areas ... well lets just say when I go camping on Moreton Island and climb the hill Google maps tells me I'm 25km away on the mainland where the nearest tower is.
Wifi puts you roughly within 30-50m.
Neither is anywhere near as accurate as GPS.
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You may be surprised how many businesses and industries rely on GPS measurements and really do need this kind of accurate location data. GPS is an infrastructure investment, just like roads, internet, public water systems, electric grid, etc., that increase the productivity of countless industries and people. The average person using their cell phone GPS probably won't notice much change, but the average person doesn't notice most of the infrastructure around them that keeps their world humming along.
Keep i
42 cm??? (Score:1)
"Six by nine. Forty two."
"That's it. That's all there is."
"I always thought something was fundamentally wrong with the universe"
-Douglas Adams
Is this backwards compatible? (Score:2)
Do new satellites drop into the existing network but with improved accuracy? Or will you need an updated device to take advantage of it?
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You don't need new gear to benefit from these IIF block birds.
The follow on ones, up next will also be backward compatible...though they will transmit an additional civ signal along with transmitting the old backward compatible one as well, to get the new (second) channel you'll likely need new gear, it's years away.
Better tracking now available!!! (Score:2)
Now you can be tracked within 42 centimeters of your actual location.
Before someone would have to go to the spot and take a second to look around for you.
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You do understand that GPS has non-military and even military purposes that don't involve dropping bombs right?
http://www.nationalgeographic.com/foodfeatures/feeding-9-billion/
GPS can help agriculture be more efficient, thus providing more output per acre, and thus more food for those very children you are so concerned about feeding.
And if you are so concerned about feeding children, may I suggest getting off your fat ass, and going to Africa to see how massively complicated the problem actually is, instead
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Were off by ~3 feet, now good within ~2 inches... (Score:4, Funny)
What are they planning, drones with sniper rifles?
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Not everything the military uses if solely for killing. There are thousands of uses of in credibly accurate GPS out there. In the near future you might learn what some of those are.
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Japan has been pioneering this technology. Civilian receivers with extra hardware can get resolution down to 5cm. They are using it for things like automated snow ploughs that can follow the side of the road perfectly. Obviously when the road is solid white you can't use optical tracking. For vehicle navigation they can also tell what lane the car is in, to improve directions given to the driver.
It's also useful for surveys. Sure, you can get centimetre accuracy with current tech, but it takes a long time.
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Which constellation of satellites are they using?
Can you point to what hardware it is that they are making, it should work in the US or elsewhere, and if it does, then I'm surprised I haven't seen it. I'd order some tomorrow if what you are saying is accurate.
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Yes. https://en.m.wikipedia.org/wik... [wikipedia.org]
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Yes. https://en.m.wikipedia.org/wik... [wikipedia.org]
I LOL'd, "...the system is controlled using a Xbox 360 video game controller"
COSPAS SARSAT (Score:1)
New GPS satellites also carry a COSPAS SARSAT package which has two purposes
1. It detects existing digital satellite beacons, but since GPS birds fly over the whole planet constantly and pretty fast, it reduces the time from when you activate the beacon until your message is processed by a ground station. When rescue is life-saving, minutes count.
2. It is ready for future beacons that will have a "back channel" so that after you activate the beacon you can receive a message e.g. "Helicopter dispatched. Move
Unfortunately it was off target (Score:2)
It ended up in a remote fishing village in Iceland, then it drove around Croatia for a couple days. Finally, it was stranded in Death Valley and over-heated.
Sorry. Couldn't resist. See later story.
Umm Guys.. (Score:1)
But I digress. Week old ne