Re:The GPS wars have begun
by megablast on Sunday December 23, 2018 @06:00AM
(#18745471)
I wonder if having all these extra satellites will increase the accuracy of GPS positioning? Surely it would, as long as they could all be used at the same time.
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Re:The GPS wars have begun
by ymolodtsov on Sunday December 23, 2018 @06:43AM
(#18745598)
It already increase, chips in the most smartphones use several systems at once.
GPS is not super accurate for average consumers. Only military has centimetres precision.
Re:The GPS wars have begun
by extrapickles on Sunday December 23, 2018 @06:34AM
(#18745572)
The new Block III GPS sats have a new civilian signal that will improve the quality of a fix as the ionosphere can be directly measured. Jury is still out on how well the extra signal will improve accuracy as there isn’t a full set of sats that broadcast it yet.
That requires a dual-frequency receiver, though, which I think is only found in high-end survey equipment and a handful of very recent and expensive smartphones.
Which smartphones are those? Is there a list somewhere?
The Xiaomi Mi 8 is a relatively inexpensive flagship-grade device with L5/E5a capability.
Re:The GPS wars have begun
by johnjonesyc on Sunday December 23, 2018 @07:55AM
(#18745814)
better list of actual capability
Unfortunately, even though there are already several phones on the market whose hardware supports dual band GPS, the software in most cases doesn't.
see this article for details https://medium.com/@sjbarbeau/dual-frequency-gnss-on-android...
My Mi 8 with the stable Android P build seems to be using both frequencies for satellites "in use" at the same time. The actual benefits of it, I don't know though.
Why are they improving civilian accuracy and will military still have more accurate fixes, or just less jammable signals?
Re:The GPS wars have begun
by extrapickles on Sunday December 23, 2018 @01:47PM
(#18747624)
Most of the upgrades to the civilian bands are for faster first fixes and making it so a fix is consistently more accurate. Also the ionosphere can be directly measured by your gps receiver, so fixes will be more accurate.
They are doing this because many civilian applications have emerged that need a more accurate signal (one is turn-by-turn navigation). When GPS was first developed, it was first envisioned as outputting coordinates and you looked up your location on a paper map, where 2m was better than most maps you could get.
The military is getting the ability to get a signal that is 100x more powerful in a small area.
It will be awhile before we see receivers using the new signal as the first of the new GPS sats launched today (some of the old ones are broadcasting the new signal, but not enough of them)